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Background and Objectives: Anterior vertebral body tether (VBT) is a fusionless approach to treat idiopathic scoliosis, and surgeons are beginning to implement the technique into current practice. This study aims to evaluate the learning curve for single and double VBT., Methods: A retrospective review of 3 surgeons' first 40 single and 20 double VBT was performed. Skeletally immature patients with idiopathic scoliosis who underwent thoracic (single) or thoracolumbar (double) VBT were included. Thoracic VBT was done via video-assisted thoracoscopic surgery and lumbar VBT through a mini-open retroperitoneal approach. Primary outcomes of interest were operative time, radiation exposure, and radiographic correction. Pooled and individual-surgeon analyses were performed., Results: A total of 180 patients were included: 120 single and 60 double. Mean age was 12.7 years, and 87.8% were female. Mean segments tethered was 7.8 in single and 11.0 in double. Mean preoperative thoracic scoliosis was 51.5: single 50.5° and double 53.3°. Mean lumbar scoliosis was 36.4°: single 30.0° and double 49.0°. Average operating time was 276.2 minutes; double VBT was significantly longer (217.3 vs 394.0 minutes, P < .001). Mean blood loss was 198.5 mL, and mean fluoroscopy dose was 73.0 mGy. For single VBT, there was a decrease in operative time (283.3-174.8 minutes, P < .001) and fluoroscopy dose (70.1-53.5 mGy, P = .047) over time. Every 10 cases resulted in a 31.4 minute decrease in operative time ( P < .001). There were no intraoperative complications. Single VBT resulted in 54.9% thoracic curve correction. Double VBT achieved 53.0% thoracic and 56.7% lumbar correction. There were no differences in curve correction across the learning curve., Conclusion: VBT is viable fusionless surgical option for scoliosis. As expected, increased experience resulted in shorter operative time; the threshold for such improvement seems to be 10 cases. Importantly, adequate and consistent curve correction can be achieved at the start of the learning curve while mitigating complications., (Copyright © Congress of Neurological Surgeons 2024. All rights reserved.)

Study Design: Retrospective cohort study., Objective: To evaluate the outcomes and reoperation rates in patients with adolescent idiopathic scoliosis undergoing lumbar anterior vertebral body tethering (AVBT)., Background: AVBT is a viable option for growing children. The benefit of motion preservation must be balanced by a higher reoperation rate. A paucity of reports has addressed lumbar AVBT., Materials and Methods: A single-center retrospective study was conducted to identify all patients who underwent lumbar AVBT (lowest instrumented vertebra L3 or L4) with a minimum of 2 years of follow-up. Clinical and radiographic parameters, including complications and reoperations, were also collected. Statistical analysis was performed using the Student t test for qualitative variables., Results: From a data set of 551 patients, we identified 106 patients (89% female) who underwent a lumbar AVBT (33 lumbar only, 73 bilateral thoracic/lumbar) with a mean follow-up of 4.1 ± 1.6 years at which point 85% (90/106) had reached skeletal maturity. Preoperatively, these patients were skeletally immature (age: 12.8 ± 1.3 yr, Sanders: 3.3 ± 0.8, R = 0.6 ± 0.9) with a lumbar coronal curve angle of 49.6° ± 11.2° which corrected to 19.9° ± 11.2° ( P < 0.0001) at most recent follow-up. At the latest follow-up, 76.4% (81/106) of the patients harbored a coronal curve angle of <30°. Twenty patients (18.9%) underwent 23 reoperations, with overcorrection being the most common (10/23, 43%). Broken tethers led to reoperation in 3 instances (3/23, 13%). Six patients in the cohort needed a posterior spinal fusion (6/106, 5.4%)., Conclusions: Vertebral body tethering is a viable treatment option for skeletally immature patients with idiopathic scoliosis. This report is the largest to date for lumbar AVBT, highlighting that 84% of patients harbored a curve <35° at the latest follow-up but with an 18.9% reoperation rate., Level of Evidence: 3., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: The STOP questionnaire was developed to document reasons for discontinuation of growth-friendly (GF) treatment in early onset scoliosis (EOS). This study investigated the incidence of parental request (PR) on the STOP questionnaire and compared clinical information and Early Onset Scoliosis 24-Item Questionnaire (EOSQ-24) scores of PR patients with those whose parents did not request discontinuation (non-parent request [NPR])., Materials and Methods: An international pediatric spine registry was queried for EOS patients with STOP questionnaires completed by their surgeon. Age at discontinuation, sex, and EOS etiology were recorded. GF device, number of surgical procedures, complications, STOP questionnaire reasons for discontinuation, and definitive treatment were recorded. EOSQ-24 scores and clinical information in the PR cohort were compared with the NPR cohort., Results: Data for 1326 patients were analyzed. PR was listed on the STOP questionnaires of 46 (3.5%) patients, completed at a mean age of 12 years (SD, 3.2 years). There were no statistical differences in number of procedures or complications when comparing the PR cohort with the NPR cohort. PR patients more frequently had neuromuscular EOS ( P =.002), more frequently were treated with magnetically controlled growing rods (33% vs 14%, P =.036), and more frequently were observed after GF discontinuation ( P =.628). EOSQ-24 scores for the PR cohort were significantly lower in most domains except pain/discomfort., Conclusion: For 3.5% of the EOS patients, PR was listed on the STOP questionnaire. They frequently had neuromuscular EOS and frequently were treated with magnetically controlled growing rods. Additionally, these patients had statistically lower EOSQ-24 scores across most domains. [ Orthopedics . 2024;47(6):e311-e316.].

Introduction: The evolution of MCGR technique has led to modifications in the configuration of the proximal construct to decrease the incidence of implant-related complications (IRC) and revision surgeries. However, there is no data characterizing the performance of the most used configurations reducing the risk of complications., Methods: 487 patients were identified from an international multicenter EOS database., Inclusion Criteria: EOS patients, primary dual MCGR, complete radiographs, and minimum of 2-year follow-up. 76 patients had incomplete X-rays, 5 had apical fusions, and 18 had inconclusive complications, leaving 388 patients for review. A digital spine template was created to document UIV; number of levels; number, type, and location of anchors; as well as implant configuration. First available postoperative and latest follow-up radiographs were reviewed by two senior surgeons and two spine fellows. UPROR due to IRC was defined as any change in proximal anchors between the postoperative and final follow-up radiographs., Results: The most common proximal construct configuration: UIV at T2 (50.0%) with 17.5% UPROR, followed by T3 (34.0%) with 12.1% UPROR; number of levels was three (57.1%) with 16.8% UPROR and two (26.0%) with 17.0% UPROR; number of proximal anchors was six (49.9%) with 14.1% UPROR and four (27.0%) with 18.3% UPROR. The most common anchors were all screws (42.0%) with 9.9% UPROR, and all hooks (26.4%) with 31.4% UPROR (P < 0.001). The construct with the lowest rate of UPROR was a UIV at T2, with six anchors (all screws) across three levels (42 cases), with 0% UPROR. Other construct combinations that yielded 0% UPROR rates were UIV of T3, six anchors (all screws) across three levels (25 cases), and a UIV of T3 with six anchors (screws and hooks) across three3 levels (9 cases)., Conclusion: Proximal anchor configuration impacts the incidence of UPROR due to IRC in MCGR. UIV at T2 and T3 compared to T4, and the use of all screws or combination of screws and hooks compared to all hooks were associated with a lower UPROR rate. The most common construct configuration was T2 UIV, three levels, six anchors, and all screws. The use of a combination of six anchors (screws or screws and hooks) across three levels with a UIV at T2 or T3 was associated with a lower UPROR rate. Additional research is needed to further evaluate the variables contributing to configuration selection and their association with IRC., (© 2024. The Author(s), under exclusive licence to Scoliosis Research Society.)

Study Design: Retrospective review of a prospectively collected multicenter registry., Objective: To evaluate health-related quality of life (HRQOL) measures in an operative cohort of patients (OP) and compare them with a matched nonoperative cohort (NON)., Summary of Background Data: Historically, the surgical outcomes of adolescent idiopathic scoliosis (AIS) have been radiographically evaluated. However, the importance of HRQOL measures and their impact on surgical outcomes are increasingly being understood., Materials and Methods: We identified 90 NON patients with curves in the operative range who were observed for at least two years. These patients were matched with an OP cohort of 689 patients. All patients completed the Scoliosis Research Society-22 (SRS-22) questionnaire at the initial evaluation and at a minimum of two-year follow-up. Subgroup comparisons were based on curve type: primary thoracic (Th), primary thoracolumbar/lumbar (TL/L), and double major (DM) curves., Results: The preoperative major curves in the Th, TL/L, and DM OP subgroups averaged 50.4°, 45.4°, and 51.5°, respectively, and 49.4°, 43.7°, and 48.9° in the NON cohort ( P >0.05). At two years postoperatively, the major curve in the Th, TL/L, and DM OP subgroups improved to 19.0°, 19.2°, and 19.3°, respectively, compared with the progression to 51.3°, 44.5°, and 49.7° in the NON group at two-year follow-up ( P <0.05). The SRS-22 self-image, mental health, satisfaction, and total scores at the two-year follow-up were significantly better in all OP subgroups ( P <0.001) but remained largely unchanged in the NON group. A significant percentage of patients ( P <0.001) in the OP cohort reported better SRS-22 scores at the two-year follow-up in the self-image, mental health, and satisfaction domains than the NON group at two years., Conclusions: Surgically treated patients with AIS have improved HRQOL outcomes in several domains compared with age-matched and curve magnitude-matched nonoperatively treated patients at two-year follow-up., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: Posterior spinal fusion (PSF) is the current gold standard in surgical treatment for adolescent idiopathic scoliosis. Vertebral body tethering (VBT) is a fusionless alternative. Shoulder balance is an important metric for outcomes and patient satisfaction. Here we compare shoulder balance outcomes between PSF and VBT., Methods: In this retrospective review, the pre-operative and post-operative absolute radiographic shoulder height (|RSH|) of 45 PSF patients were compared to 46 VBT patients. Mean values were compared and then collapsed into discrete groups (|RSH| GROUP) and compared. Patients were propensity score matched. Regression models based on pretest-posttest designs were used to compare procedure type on post-operative outcomes., Results: Pre-operatively there were no differences in |RSH| between PSF and VBT, however, at latest post-operative follow-up PSF maintained a larger |RSH| imbalance compared to VBT (0.91 cm vs 0.63 cm, p = 0.021). In an ANCOVA regression, PSF was associated with a larger |RSH| imbalance compared to VBT, F(1, 88) = 5.76, p = 0.019. An ordinal logistic regression found that the odds ratio of being in a worse |RSH| GROUP for PSF vs VBT is 2.788 (95% CI = 1.099 to 7.075), a statistically significant effect χ 2 (1) = 4.658, p = 0.031. Results were similar in subgroup analyses of Lenke 1 and Lenke 2 patients, though to less statistical significance., Conclusion: While PSF was found to be associated with worse |RSH| outcomes, the actual numbers (2-3 mm) are unlikely to be clinically meaningful. Thus, in this analysis, VBT can be said to show comparable shoulder balance outcomes to PSF., (© 2024. The Author(s), under exclusive licence to Scoliosis Research Society.)

Study Design: Retrospective, single-center study., Objective: To examine pulmonary function tests (PFTs) in patients undergoing anterior vertebral body tethering (AVBT)., Summary of Background Data: The effect of AVBT on pulmonary status remains unclear., Materials and Methods: The authors examined preoperative and postoperative PFTs following AVBT in a retrospective, single-center cohort of patients. Outcomes were compared using percent predicted values as continuous and categorical variables (using 10% change as significant) and divided into categorical values based on the American Thoracic Society standards., Results: Fifty-eight patients with adolescent idiopathic scoliosis were included, with a mean age of 12.5±1.4 years and a follow-up of 4.2±1.1 years. The mean thoracic curve was 47°±9°, which improved to 21°±12°. At baseline, the mean forced expiratory volume in one second (FEV1%) and forced vital capacity (FVC%) values were 79% and 82%, respectively. Four patients had normal FEV1% (≥100%), 67% had mild restrictive disease (70%-99%) and the rest had worse FEV1%. Mean FEV1 improved from 2.2 to 2.6 L ( P <0.05) and FVC improved from 2.5 to 3.0 L ( P <0.05); however, % predicted values remained unchanged (FEV1%: 79%-80%; FVC%: 82-80%, P >0.05) with mean postoperative PFTs at 37±12 months postoperative. The use of miniopen thoracotomy was not associated with worsening PFTs, but extension of the lowest instrumented vertebra below T12 was correlated with decreasing FEV1% in the bivariate analysis ( P <0.05). Patients with worse preoperative FVC% (80±13% vs. 90±11%, P =0.03) and FEV1% (77±17% vs. 87±12%, P =0.06) also had a greater likelihood of declining postoperative FEV1%., Conclusion: Pulmonary function in most patients undergoing AVBT remained stable (76%) or improved (14%); however, a subset may worsen (10%). Further studies are needed to identify the risk factors for this group, but worse preoperative PFTs and extension below T12 may be risk factors for worsening pulmonary function., Competing Interests: The authors report no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Thoracic anterior vertebral body tethering (TAVBT) is an emerging treatment for adolescent idiopathic scoliosis. Tether breakage is a known complication of TAVBT with incompletely known incidence. We aim to define the incidence of tether breakage in patients with adolescent idiopathic scoliosis who undergo TAVBT. The incidence of tether breakage in TAVBT is hypothesized to be high and increase with time postoperatively., Methods: All patients with right-sided, thoracic curves who underwent TAVBT with at least 2 and up to 3 years of radiographic follow-up were included. Tether breakage between 2 vertebrae was defined a priori as any increase in adjacent screw angle >5 degrees from the minimum over the follow-up period. The presence and timing of tether breakage were noted for each patient. A Kaplan-Meier survival analysis was performed to calculate expected tether breakage up to 36 months. χ 2 analysis was performed to examine the relationship between tether breakage and reoperations. Independent t test was used to compare the average final Cobb angle between cohorts., Results: In total, 208 patients from 10 centers were included in our review. Radiographically identified tether breakage occurred in 75 patients (36%). The initial break occurred at or beyond 24 months in 66 patients (88%). Kaplan-Meier survival analysis estimated the cumulative rate of expected tether breakage to be 19% at 24 months, increasing to 50% at 36 months. Twenty-one patients (28%) with a radiographically identified tether breakage went on to require reoperation, with 9 patients (12%) requiring conversion to posterior spinal fusion. Patients with a radiographically identified tether breakage went on to require conversion to posterior spinal fusion more often than those patients without identified tether breakage (12% vs. 2%; P =0.004). The average major coronal curve angle at final follow-up was significantly larger for patients with radiographically identified tether breakage than for those without tether breakage (31 deg±12 deg vs. 26 deg±12 deg; P =0.002)., Conclusions: The incidence of tether breakage in TAVBT is high, and it is expected to occur in 50% of patients by 36 months postoperatively., Level of Evidence: Level IV., Competing Interests: Compliance with Ethical Standards: (i) This study was given Ethical Approval by the Institutional Review Board prior to the conduct of this study. (ii) Informed consent was obtained from all participants. (iii) The authors received no funding for the preparation of this manuscript. (iv) The authors of this work have no disclosures or potential conflicts of interest related to this study. B.S.L.: Consultant and speaker’s bureau for Zim Vie Tether and receives royalties. J.M.P.: Consultant for ZimVie. A.A.: Consultant for Zimvie and receives royalties. L.C.B.: PATENTS (1) Kunes; Brian; (Washington, DC); Hollins; Stacy; (New Castle, VA); Blakemore; Laurel; (Falls Church, VA); Hsu; Brian; (Greenwich, AU); Ferguson; John; (Auckland, NZ). Anterior tether tensioner. US Patent Application 17/091773, filed November 6, 2020. (2) Blakemore, Laurel (Williston, FL) Ross, Catherine(Arlington, VA). Tethering Screw System. US Patent 10,548,639. Filed April 25, 2016, issued February 4, 2020. P.O.N.: ZimVie through Setting Scoliosis Straight Foundation—Research support. A.F.S.: Zim Vie—IP royalties and paid consultant. L.L.H.: Zimmer: Paid presenter or speaker. S.A.S.: Globus Medical Royalties. The remaining authors declare no conflicts of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: There is significant debate regarding the indications of staged surgery for severe adolescent spinal deformity, and the factors associated with the decision to perform staged compared to same-day surgery have not been previously investigated. Thus, the purpose of this study was to determine which factors were most strongly associated with this decision., Methods: A prospective multicenter registry of adolescent patients with severe spinal deformity was reviewed. Two cohorts were identified: those who underwent a planned staged surgical procedure for deformity correction and those who underwent a same-day procedure. Patients who underwent an unplanned staged procedure secondary to complications during the initial procedure were excluded. Comparisons were made between these cohorts with respect to preoperative patient and radiographic variables to determine which factors were associated with the decision to perform a staged procedure. Surgical data was also compared to evaluate for differences in the intraoperative management of staged versus same-day patients., Results: Two hundred and twenty-nine patients with severe spinal deformities were identified. Forty patients (17%) underwent a planned staged procedure and 189 patients (80%) underwent a same-day procedure. On univariate analysis of preoperative variables, patients who underwent staged surgery had a significantly younger age at surgery, greater major curve magnitude, greater major curve AVT to CSVL, lesser thoracic spine height, greater radiographic trunk shift, and a greater proportion of patients undergoing revision surgery (as opposed to primary correction) compared to those who underwent a planned single-stage procedure. Multivariate logistic regression of pre-operative variables showed that age < 16 years, maximum cobb angle ≥ 120 degrees, major curve AVT to CSVL of ≥ 3.5 cm, and revision surgery were independently associated with the decision to perform a staged procedure. Intraoperatively, patients in the staged cohort more frequently underwent combined anterior and posterior procedures, grade 4 or higher Schwab osteotomies, and had a greater number of levels fused., Conclusion: There is substantial variability with respect to the decision to perform surgery for severe adolescent spine deformities in a staged versus same-day fashion. This large analysis of prospectively collected data is the first to describe the factors most strongly associated with the decision to perform a staged procedure and may help guide the surgical decision-making for these patients., (© 2023. The Author(s), under exclusive licence to Scoliosis Research Society.)

Purpose: To assess the complication risks associated with intrathecal baclofen (ITB) pumps in cerebral palsy (CP) patients undergoing posterior spinal fusion (PSF) and to determine if timing of pump implantation before or during PSF impacts the risk of complications., Methods: A prospectively collected multicenter database was retrospectively reviewed to identify CP patients undergoing PSF from 2008 to 2023. Patients were divided into 2 cohorts: those with an ITB pump (ITB cohort) and those without (non-ITB cohort). The ITB cohort was further categorized by placement of the pump prior to or during PSF. Cohorts were then compared in terms of postoperative complications, perioperative complications, and need for revision surgery., Results: Four hundred six patients (ITB n = 79 [53 prior to, 26 during PSF], non-ITB n = 326) were included in this analysis. At an average follow-up of 4.0 years (range 2-10 years), there were no significant differences between the ITB and non-ITB cohorts in the rate of perioperative complications (5.0% vs 6.5%, p = 0.80), revision surgeries (2.5% vs 4.6%, p = 0.54), or any complication type, regardless of whether pumps were placed prior to or during PSF, aside from longer surgical times in the latter group., Conclusion: Complication rates are similar for ITBs placed prior to and during PSF. Patients with spastic CP may safely be treated with ITB pumps without increased risks of complication or further reoperation/revision following PSF., Level of Evidence: Level III., (© 2023. The Author(s), under exclusive licence to Scoliosis Research Society.)

Study Design: Retrospective multicenter study., Objective: We reviewed 15-year trends in operative factors, radiographic and quality of life outcomes, and complication rates in children with cerebral palsy (CP)-related scoliosis who underwent spinal fusion., Summary of Background Data: Over the past two decades, significant efforts have been made to decrease complications and improve outcomes of this population., Materials and Methods: We retrospectively reviewed a multicenter registry of pediatric CP patients who underwent spinal fusion from 2008 to 2020. We evaluated baseline and operative, hospitalization, and complication data as well as radiographic and quality of life outcomes at a minimum 2-year follow-up., Results: Mean estimated blood loss and transfusion volume declined from 2.7±2.0 L in 2008 to 0.71±0.34 L in 2020 and 1.0±0.5 L in 2008 to 0.5±0.2 L in 2020, respectively, with a concomitant increase in antifibrinolytic use from 58% to 97% (all, P <0.01). Unit rod and pelvic fusion use declined from 33% in 2008 to 0% in 2020 and 96% in 2008 to 79% in 2020, respectively (both, P <0.05). Mean postoperative intubation time declined from 2.5±2.6 to 0.42±0.63 days ( P< 0.01). No changes were observed in preoperative and postoperative coronal angle and pelvic obliquity, operative time, frequency of anterior/anterior-posterior approach, and durations of hospital and intensive care unit stays. Improvements in the Caregiver Priorities and Child Health Index of Life with Disabilities postoperatively did not change significantly over the study period. Complication rates, including reoperation, superficial and deep surgical site infection, and gastrointestinal and medical complications remained stable over the study period., Conclusions: Over the past 15 years of CP scoliosis surgery, surgical blood loss, transfusion volumes, duration of postoperative intubation, and pelvic fusion rates have decreased. However, the degree of radiographic correction, the rates of surgical and medical complications (including infection), and health-related quality of life measures have broadly remained constant., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Anterior Vertebral Body Tethering (AVBT) is a growing alternative treatment for adolescent idiopathic scoliosis (AIS), offering an option besides spinal fusion. While AVBT aims to correct spinal deformity through growth correction, its outcomes have been mixed. To improve surgical outcomes, this study aimed to develop a machine learning-based tool to predict short- and midterm spinal curve correction in AIS patients who underwent AVBT surgery, using the most predictive clinical, radiographic, and surgical parameters. After institutional review board approval and based on inclusion criteria, 91 AIS patients who underwent AVBT surgery were selected from the Shriners Hospitals for Children, Philadelphia. For all patients, longitudinal standing (PA or AP, and lateral) and side bending spinal Radiographs were retrospectively obtained at six visits: preop and first standing, one year, two years, five years postop, and at the most recent follow-up. Demographic, radiographic, and surgical features associated with curve correction were collected. The sequential backward feature selection method was used to eliminate correlated features and to provide a rank-ordered list of the most predictive features of the AVBT correction. A Gradient Boosting Regressor (GBR) model was trained and tested using the selected features to predict the final correction of the curve in AIS patients. Eleven most predictive features were identified. The GBR model predicted the final Cobb angle with an average error of 6.3 ± 5.6 degrees. The model also provided a prediction interval, where 84% of the actual values were within the 90% prediction interval. A list of the most predictive features for AVBT curve correction was provided. The GBR model, trained on these features, predicted the final curve magnitude with a clinically acceptable margin of error. This model can be used as a clinical tool to plan AVBT surgical parameters and improve outcomes., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Alfraihat et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Vertebral body tethering and other non-fusion techniques for the treatment of pediatric idiopathic scoliosis are increasing in popularity. There is limited physician consensus on this topic as the result of a paucity of published data regarding which patients most benefit from non-fusion strategies. Thus, much of the decision-making is left to patients and parents, who must select a treatment based on their goals and values and the information available from health-care providers, the internet, and social media. We sought to understand patient and family preferences regarding the attributes of fusion versus non-fusion surgery that drive these choices., Methods: Patients and families were recruited from 7 pediatric spine centers and were asked to complete a survey-based choice experiment that had been jointly developed with the U.S. Food and Drug Administration (FDA) to evaluate patient preferences. Choices between experimentally designed alternatives were analyzed to estimate the relative importance of outcomes and requirements associated with the choice options (attributes). The attributes included appearance, confidence in the planned correction, spinal motion, device failure, reoperation, and recovery period. The inclusion criteria were (1) an age of 10 to 21 years and (2) a diagnosis of adolescent idiopathic scoliosis in patients who were considering, or who had already undergone, treatment with fusion or non-fusion surgery. Preference weights were estimated from the expected changes in choice given changes in the attributes., Results: A total of 344 respondents (124 patients, 92 parents, and 128 parent/patient dyads) completed the survey. One hundred and seventy-three patients were enrolled prior to surgery, and 171 were enrolled after surgery. Appearance and motion were found to be the most important drivers of choice. For the entire cohort, fusion was preferred over non-fusion. For patients who were considering surgery, the most important attributes were preservation of spinal motion and appearance., Conclusions: Patients and families seeking treatment for idiopathic scoliosis value appearance and preservation of spinal motion and, to a lesser extent, reoperation rates when considering fusion versus non-fusion surgery., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article ( http://links.lww.com/JBJS/H751 )., (Copyright © 2023 Written work prepared by employees of the Federal Government as part of their official duties is, under the United States Copyright Act, a ‘work of the United States Government’ for which copyright protection under that Act is not available. As such, copyright protection does not extend to the contributions of employees of the Federal Government prepared as part of their employment.)

Purpose: To evaluate intraoperative monitoring (IOM) alerts and neurologic deficits during severe pediatric spinal deformity surgery., Methods: Patients with a minimum Cobb angle of 100° in any plane or a scheduled vertebral column resection (VCR) with minimum 2-year follow-up were prospectively evaluated (n = 243). Preoperative, immediate postoperative, and 2-year postoperative neurologic status were reported. Radiographic data included preoperative and 2-year postoperative coronal and sagittal Cobb angles and deformity angular ratios (DAR). IOM alert type and triggering event were recorded. SRS-22r scores were collected preoperatively and 2-years postoperatively., Results: IOM alerts occurred in 37% of procedures with three-column osteotomy (n = 36) and correction maneuver (n = 32) as most common triggering events. Patients with IOM alerts had greater maximum kyphosis (101.4° vs. 87.5°) and sagittal DAR (16.8 vs. 12.7) (p < 0.01). Multivariate regression demonstrated that sagittal DAR independently predicted IOM alerts (OR 1.05, 95% CI 1.02-1.08) with moderate sensitivity (60.2%) and specificity (64.8%) using a threshold value of 14.3 (p < 0.01). IOM alerts occurred more frequently in procedures with new postoperative neurologic deficits (17/24), and alerts with both SSEP and TCeMEP signals were associated with new postoperative deficits (p < 0.01). Most patients with new deficits experienced resolution at 2 years (16/20) and had equivalent postoperative SRS-22r scores. However, patients with persistent deficits had worse SRS-22r total score (3.8 vs. 4.2), self-image subscore (3.5 vs. 4.1), and function subscore (3.8 vs. 4.3) (p ≤ 0.04)., Conclusion: Multimodal IOM alerts are associated with sagittal kyphosis, and predict postoperative neurologic deficits. Most patients with new deficits experience resolution of their symptoms and have equivalent 2-year outcomes., Level of Evidence: II., (© 2023. The Author(s), under exclusive licence to Scoliosis Research Society.)

Study Design: Retrospective review of a prospectively collected multicenter database., Objective: To compare outcomes of patients with cerebral palsy (CP) who undergo surgery for scoliosis with normal lordosis (NL) versus hyperlordosis., Summary of Background Data: Surgical correction of scoliosis with lumbar hyperlordosis is challenging. Hyperlordosis may confer higher perioperative morbidity, but this is not well understood., Materials and Methods: A multicenter database was queried for CP patients who underwent surgery from 2008 to 2017. The minimum follow-up was 2 years. Two groups were identified: lumbar lordosis <75° (NL) versus ≥ 75° hyperlordosis (HL). Perioperative, radiographic, and clinical outcomes were compared., Results: Two hundred seventy-five patients were studied: 236 NL and 39 HL (-75 to -125°). The mean age was 14.1 years, and 52.4% were male. Patients with hyperlordosis had less cognitive impairment (76.9% vs. 94.0%, P =0.008) and higher CPCHILD scores (59.4 vs. 51.0, P =0.003). Other demographics were similar between the groups. Patients with hyperlordosis had greater lumbar lordosis (-90.5 vs. -31.5°, P <0.001) and smaller sagittal vertical axis (-4.0 vs. 2.6 cm, P <0.001). Patients with hyperlordosis had greater estimated blood loss (2222.0 vs. 1460.7 mL, P <0.001) but a similar perioperative complication rate (20.5% vs. 22.5%, P =0.787). Significant correction of all radiographic parameters was achieved in both groups. The HL group had postoperative lumbar lordosis of -68.2° and sagittal vertical axis of -1.0 cm. At a 2-year follow-up, patients with hyperlordosis continued to have higher CPCHILD scores and gained the greatest benefit in overall quality of life measures (20.0 vs. 6.1, P =0.008). The reoperation rate was 10.2%: implant failure (3.6%), pseudarthrosis (0.7%), and wound complications (7.3%). There were no differences in the reoperation rate between the groups., Conclusion: Surgical correction of scoliosis with hyperlordosis is associated with greater estimated blood loss but similar radiographic results, perioperative morbidity, and reoperation rate as normal lordosis. Patients with hyperlordosis gained greater overall health benefits. Correction of ≥25% of hyperlordosis seems satisfactory., Level of Evidence: 3., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Study Design: Prospective multicenter cohort study., Objective: To evaluate perioperative complications and mid-term outcomes for severe pediatric spinal deformity., Summary of Background Data: Few studies have evaluated the impact of complications on health-related quality of life (HRQoL) outcomes in severe pediatric spinal deformity., Methods: Patients from a prospective, multicenter database with severe pediatric spinal deformity (minimum of 100 degree curve in any plane or planned vertebral column resection (VCR)) with a minimum of 2-years follow-up were evaluated (n=231). SRS-22r scores were collected preoperatively and at 2-years postoperatively. Complications were categorized as intraoperative, early postoperative (within 90-days of surgery), major, or minor. Perioperative complication rate was evaluated between patients with and without VCR. Additionally, SRS-22r scores were compared between patients with and without complications., Results: Perioperative complications occurred in 135 (58%) patients, and major complications occurred in 53 (23%) patients. Patients that underwent VCR had a higher incidence of early postoperative complications than patients without VCR (28.9% vs. 16.2%, P =0.02). Complications resolved in 126/135 (93.3%) patients with a mean time to resolution of 91.63 days. Unresolved major complications included motor deficit (n=4), spinal cord deficit (n=1), nerve root deficit (n=1), compartment syndrome (n=1), and motor weakness due to recurrent intradural tumor (n=1). Patients with complications, major complications, or multiple complications had equivalent postoperative SRS-22r scores. Patients with motor deficits had lower postoperative satisfaction subscore (4.32 vs. 4.51, P =0.03), but patients with resolved motor deficits had equivalent postoperative scores in all domains. Patients with unresolved complications had lower postoperative satisfaction subscore (3.94 vs. 4.47, P =0.03) and less postoperative improvement in self-image subscore (0.64 vs. 1.42, P =0.03) as compared to patients with resolved complications., Conclusion: Most perioperative complications for severe pediatric spinal deformity resolve within 2-years postoperatively and do not result in adverse HRQoL outcomes. However, patients with unresolved complications have decreased HRQoL outcomes., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Optimal orientation for magnetically controlled growing rods (MCGRs) is unclear. The objective of this study was to investigate associations of rod orientation with implant-related complications (IRCs) and spinal height gains. Using an international early-onset scoliosis (EOS) database, we retrospectively reviewed 57 patients treated with dual MCGRs from May 2013 to July 2015 with minimum 2-year follow-up. Outcomes of interest were IRCs and left/right rod length gains and thoracic (T1-T12) and spinal (T1-S1) heights. We compared patients with two rods lengthened in the cephalad ( standard; n  = 18) versus opposite ( offset; n  = 39) directions. Groups did not differ in age, sex, BMI, duration of follow-up, EOS cause, ambulatory status, primary curve magnitude, baseline thoracic height, or number of distractions/year. We compared patients whose constructs used ≥1 cross-link (CL group; n  = 22) versus no CLs (NCL group; n  = 35), analyzing thoracic height gains per distraction ( α  = 0.05). Offset and standard groups did not differ in left or right rod length gains overall or per year or in thoracic or spinal height gain. Per distraction, the CL and NCL groups did not differ significantly in left or right rod length or thoracic or spinal height gain. Complications did not differ significantly between rod orientation groups or between CL groups. MCGR orientation and presence of cross-links were not associated with differences in rod length gain, thoracic height, spinal height, or IRCs at 2-year follow-up. Surgeons should feel comfortable using either MCGR orientation. Level of evidence: 3, retrospective., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Study Design: Retrospective case series., Objective: To examine the incidence and risk factors for postoperative pain following anterior vertebral body tethering (AVBT) for adolescent idiopathic scoliosis (AIS)., Summary of Background Data: Up to 78% of patients with AIS report preoperative pain; it is the greatest patient concern surrounding surgery. Pain significantly decreases following posterior spinal fusion, but pain following AVBT is poorly understood., Materials and Methods: We retrospectively reviewed 279 patients with a two-year follow-up after AVBT for AIS. We collected demographic, radiographic, and clinical data pertinent to postoperative pain at each time interval of preoperative and postoperative visits (6 wk, 6 mo, 1 y, and annually thereafter)., Results: Within our cohort, 68.1% of patients reported preoperative pain. Older age ( P =0.014) and greater proximal thoracic ( P =0.013) and main thoracic ( P =0.002) coronal curve magnitudes were associated with preoperative pain. Pain at any time point > 6 weeks postoperatively was reported in 41.6% of patients; it was associated with the female sex ( P =0.032), need for revision surgery ( P =0.019), and greater lateral displacement of the apical lumbar vertebrae ( P =0.028). The association between preoperative and postoperative pain trended toward significance ( P =0.07). At 6 months postoperatively, 91.8% had pain resolution; the same number remained pain-free at the time of last follow-up. The presence of a postoperative complication was associated with new-onset postoperative pain that resolved ( P =0.009). Only 8.2% had persistent pain, although no risk factors were found to be associated with persistent pain., Conclusion: In our cohort of 279 patients with a minimum 2-year follow-up after AVBT, 68.1% reported preoperative pain. Nearly 42% reported postoperative pain at any time point, but only 8.2% had persistent pain. Postoperative pain after AVBT was associated with female sex, revision surgery, and Lenke lumbar modifier. AVBT is associated with a significant reduction in pain, and few patients report long-term postoperative pain., Competing Interests: The authors report no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Study Design: Retrospective review., Objective: To study risk factors for anterior vertebral body tether (VBT) breakage., Summary of Background Data: VBT is used to treat adolescent idiopathic scoliosis in skeletally immature patients. However, tethers break in up to 48% of cases., Materials and Methods: We reviewed 63 patients who underwent thoracic and/or lumbar VBT with a minimum five-year follow-up. We radiographically characterized suspected tether breaks as a change in interscrew angle >5°. Demographic, radiographic, and clinical risk factors for presumed VBT breaks were evaluated., Results: In confirmed VBT breaks, the average interscrew angle change was 8.1°, and segmental coronal curve change was 13.6°, with a high correlation ( r =0.82). Our presumed VBT break cohort constituted 50 thoracic tethers, four lumbar tethers, and nine combined thoracic/lumbar tethers; the average age was 12.1±1.2 years and the mean follow-up was 73.1±11.7 months. Of 59 patients with thoracic VBTs, 12 patients (20.3%) had a total of 18 breaks. Eleven thoracic breaks (61.1%) occurred between two and five years postoperatively, and 15 (83.3%) occurred below the curve apex ( P <0.05). The timing of thoracic VBT breakage moderately correlated with more distal breaks ( r =0.35). Of 13 patients who underwent lumbar VBT, eight patients (61.5%) had a total of 12 presumed breaks. Six lumbar breaks (50%) occurred between one and two years postoperatively, and seven (58.3%) occurred at or distal to the apex. Age, sex, body mass index, Risser score, and curve flexibility were not associated with VBT breaks, but the association between percent curve correction and thoracic VBT breakage trended toward significance ( P =0.054). Lumbar VBTs were more likely to break than thoracic VBTs ( P =0.016). Seven of the patients with presumed VBT breaks (35%) underwent revision surgery., Conclusions: Lumbar VBTs broke with greater frequency than thoracic VBTs, and VBT breaks typically occurred at levels distal to the curve apex. Only 15% of all patients required revision., Level of Evidence: 3., Competing Interests: A.F.S.: consultant for DePuy Synthes Spine, Ethicon, Globus Medical, Medical Device Business Services, Mirus, NuVasive, Orthofix, Stryker, ZimVie; Royalties from NuVasive and ZimVie. J.M.P.: consultant for DePuy Synthes Spine, NuVasive, and ZimVie. S.W.H.: consultant for NuVasive, ZimVie; Speakers bureau DePuy Synthes Spine, NuVasive, ZimVie; Stocks/options: Auctus. The remaining authors report no conflicts of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: This study describes the creation of patient-specific (PS) osteo-ligamentous finite element (FE) models of the spine, ribcage, and pelvis, simulation of up to three years of region-specific, stress-modulated growth, and validation of simulated curve progression with patient clinical angle measurements., Research Question: Does the inclusion of region-specific, stress-modulated vertebral growth, in addition to scaling based on age, weight, skeletal maturity, and spine flexibility allow for clinically accurate scoliotic curve progression prediction in patient-specific FE models of the spine, ribcage, and pelvis?, Methods: Frontal, lateral, and lateral bending X-Rays of five AIS patients were obtained for approximately three-year timespans. PS-FE models were generated by morphing a normative template FE model with landmark points obtained from patient X-rays at the initial X-ray timepoint. Vertebral growth behavior and response to stress, as well as model material properties were made patient-specific based on several prognostic factors. Spine curvature angles from the PS-FE models were compared to the corresponding X-ray measurements., Results: Average FE model errors were 6.3 ± 4.6°, 12.2 ± 6.6°, 8.9 ± 7.7°, and 5.3 ± 3.4° for thoracic Cobb, lumbar Cobb, kyphosis, and lordosis angles, respectively. Average error in prediction of vertebral wedging at the apex and adjacent levels was 3.2 ± 2.2°. Vertebral column stress ranged from 0.11 MPa in tension to 0.79 MPa in compression., Conclusion: Integration of region-specific stress-modulated growth, as well as adjustment of growth and material properties based on patient-specific data yielded clinically useful prediction accuracy while maintaining physiological stress magnitudes. This framework can be further developed for PS surgical simulation., (© 2023. The Author(s).)

Background: Gabapentin has been adopted in Enhanced Recovery After Surgery protocols as a means to reduce opioid consumption while maintaining adequate post-operative analgesia. The purpose of our study was to review and compare changes in length of stay, opioid use, and patient reported pain scores after the addition of gabapentin into five, distinct pain protocols for posterior spinal fusion in adolescent idiopathic scoliosis., Methods: A retrospective review was completed using a database of electronic medical data from a single pediatric orthopedic healthcare system that was queried for patients with adolescent idiopathic scoliosis who underwent first-time posterior spinal fusion. Perioperative data including demographics, hospital length of stay, surgical details, opioid use, patient reported pain scores, and non-opioid analgesic use were collected., Results: From December 2012 to February 2019, 682 hospitalizations for posterior spinal fusion in adolescent idiopathic scoliosis were identified with complete inpatient data; 49% were administered gabapentin. For the gabapentin cohort, the system saw no statistically significant effect on length of stay or pain averaged over POD#0-3. Opioid use was statistically lower averaged over POD#0-3. Individual sites saw variation on length of stay and opioid use compared to the system., Conclusion: In conclusion, system-wide data showed gabapentin containing protocols reduced opioid use while maintaining clinically equivalent analgesia. However, variations of individual site results make it difficult to conclude the degree to which gabapentin were responsible for this effect., (© 2023. The Author(s).)

Purpose: Given the challenges associated with managing progressive scoliosis in patients with cerebral palsy (CP), the purpose of this study was to evaluate deformity correction and HRQOL 5 years post-spinal fusion in CP patients who were skeletally immature at the time of surgical correction., Methods: CP patients who underwent definitive fusion before age 11 with minimum 5-years follow-up from a prospective, multicenter registry were included. Preoperative, initial postoperative, and 5-years radiographic data were collected. Preoperative and 5-years demographic, surgical data, complications, and CPCHILD outcome scores were analyzed. Repeated measures ANOVA with Bonferroni adjustment were used to analyze radiographic measures. Paired t test was utilized to compare outcomes. Significance was set at p = 0.05., Results: Twenty patients met inclusion-17 females, 3 males. The mean age was 9 (range 8-10) years. Eight-five percent had spastic CP with GMFCS Level V. Eighteen patients underwent posterior fusion; distal fixation was to the ilium in 80% and to L4-S1 in 20%. Significant correction of the primary curve (p ≤ 0.001) and pelvic obliquity (p ≤ 0.001) were obtained. From initial postoperative to 5-years follow-up there were no significant changes in major curve magnitude (p = 0.638), thoracic kyphosis (p = 0.09) or pelvic obliquity (p = 0.28). CPCHILD personal care, mobility, comfort, and total scores improved from preoperative to 5-years (p < 0.05). One patient needed a reoperation., Conclusion: Surgical decision making for scoliosis in patients with CP can be difficult given the desire to maximize growth while minimizing adverse events. Performing a definitive fusion is a viable option that achieves good correction which remains stable 5 years postoperatively., (© 2022. The Author(s), under exclusive licence to Scoliosis Research Society.)

Background: Anterior vertebral body tethering (AVBT) for adolescent idiopathic scoliosis (AIS) is postulated to preserve motion compared with traditional posterior spinal fusion (PSF), but few studies exist to date. We used a validated computerized 3D model to compare trunk motion between patients treated with PSF and AVBT, and analyzed trunk motion in relation to the lowest instrumented vertebra (LIV)., Methods: This was a single-center retrospective review of a consecutive series of skeletally immature patients with AIS who underwent motion analysis prior to PSF (n = 47) or AVBT (n = 65) and 2 years postoperatively. Patients were divided into 4 groups on the basis of the LIV (≤L1, L2, L3, L4). Computerized 3D kinematic evaluations included thoracic and lumbar flexion, extension, side-bending, and rotation. Patient outcomes were assessed using the Scoliosis Research Society (SRS)-22 questionnaire., Results: The LIV was ≤L1 in 48 patients treated with AVBT and 23 treated with PSF, L2 in 4 AVBT and 8 PSF patients, L3 in 10 AVBT and 8 PSF patients, and L4 in 3 AVBT and 8 PSF patients. PSF patients had a significant loss of motion in all 4 directions at 2 years postoperatively (e.g., flexion loss was 11° for ≤L1 to 30° for L4; p < 0.001). This equated to a 7° loss of trunk flexion per additional LIV level included in the fusion. AVBT patients only demonstrated loss of flexion and side-bending at 2 years postoperatively (e.g., flexion loss of 11° for L1 to 17° for L4; p < 0.001). Preoperative curve size and flexibility did not have any significant impact on differences in trunk motion between AVBT and PSF. SRS-22 scores were predominantly similar for AVBT versus PSF preoperatively and at 2 years postoperatively., Conclusions: Patients treated with AVBT experienced predominantly less motion loss compared with PSF patients at 2 years postoperatively. Patients treated with PSF demonstrated loss of motion in all planes that increased with each additional LIV from ≤L1 to L4, with 7° loss of flexion per additional LIV. However, the differences in total trunk motions were relatively modest for PSF and AVBT with an LIV of ≤L1. Preoperative curve magnitude and flexibility had no significant impact on trunk motion in either group. SRS-22 scores were similar for both groups at 2 years postoperatively., Level of Evidence: Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article ( http://links.lww.com/JBJS/H123 )., (Copyright © 2022 by The Journal of Bone and Joint Surgery, Incorporated.)

Background: Accurate reporting of long-term complications of surgical treatment of adolescent idiopathic scoliosis (AIS) is critical, but incomplete. This study aimed to report on the rate of complications following surgical treatment of AIS among patients with at least 10 years of follow-up., Methods: This was a retrospective review of prospectively collected data from a multicenter registry of patients who underwent surgical treatment for AIS with minimum 10-year follow-up. Previously published complications were defined as major if they resulted in reoperation, prolonged hospital stay/readmission, neurological deficits, or were considered life-threatening. Rates and causes of reoperations were also reviewed., Results: Two hundred and eighty-two patients were identified with mean age at surgery of 14.6 ± 2.1 years. Mean follow-up was 10.6 (range 9.5-14) years. Eighty-seven patients had anterior spinal fusion (ASF); 195 had posterior spinal fusion (PSF). The overall major complication rate was 9.9% (n = 28) in 27 patients. Among PSF patients, the complication rate was 9.7% (n = 19) in 18 patients. The complications were surgical site infection (37%), adding-on (26%), pulmonary (16%), neurologic (11%), instrumentation (5%), and gastrointestinal (5%). In ASF patients, the complication rate was 10.3% (n = 9) among nine patients. The complications were pulmonary (44%), pseudoarthrosis (22%), neurologic (11%), adding-on (11%), and gastrointestinal (11%). The reoperation rate was 6.0% (n = 17) among 17 patients. Although most of the complications presented within the first 2 years (60.7%), surgical site infection and adding-on were also seen late into the 10-year period., Conclusion: This is the largest prospective study with at least a 10-year follow-up of complications following spinal fusion for AIS, the overall major complication rate was 9.9% with a reoperation rate of 6.0%. Complications presented throughout the 10-year period, making long-term follow-up very important for surveillance., Level of Evidence: Therapeutic II., (© 2022. The Author(s), under exclusive licence to Scoliosis Research Society.)

Purpose: Prior work identified optimal outcomes at 2 years following selective thoracic fusion (STF) for adolescent idiopathic scoliosis (AIS) but it is unclear whether these published predictors represent what is required to achieve an optimal outcome with further time and potential growth. The purpose of this study was to determine the preoperative factors associated with optimal outcome of STF for AIS at 5 years., Methods: Patients with primary thoracic AIS (Lenke 1-4C curves) who underwent a STF and had minimum 5 years of follow-up were included. Optimal postoperative outcomes for a STF included a deformity-flexibility quotient (DFQ) < 4, lumbar curve < 26°, lumbar correction > 37%, C7-CSVL < 2 cm, lumbar prominence < 5°, and trunk shift < 1.5 cm. These outcomes were used to determine whether adhering to published recommendations for STF increased the likelihood of obtaining an optimal outcome at 5 years, which included: preoperative lumbar curve < 45°, lumbar bend < 25°, apical vertebral translation ratio > 1.2, and thoracic/thoracolumbar Cobb ratio > 1.2., Results: 127 patients met inclusion. A preoperative lumbar curve < 45° was associated with an increased likelihood of achieving three of the optimal outcomes: DFQ < 4, lumbar curve < 26°, and lumbar prominence < 5°. Following the 25° bend rule resulted in two optimal outcomes, while Cobb ratio > 1.2 was only associated with one optimal outcome. AVT > 1.2 was not significantly associated with any optimal outcome measures., Conclusion: This study found that at 5 years, performing a STF when there is a preoperative lumbar Cobb < 45° remained the best guideline for increasing the likelihood of an optimal outcome., (© 2022. The Author(s), under exclusive licence to Scoliosis Research Society.)

Background: Adolescent Idiopathic Scoliosis (AIS) is a three-dimensional (3D) spinal deformity characterized by coronal curvature and rotational deformity. Predicting curve progression is important for the selection and timing of treatment. Although there is a consensus in the literature regarding prognostic factors associated with curve progression, the order of importance, as well as the combination of factors that are most predictive of curve progression is unknown., Objectives: (1) create an ordered list of prognostic factors that most contribute to curve progression, and (2) develop and validate a Machine Learning (ML) model to predict the final major Cobb angle in AIS patients., Methods: 193 AIS patients were selected for the current study. Preoperative PA, lateral and lateral bending radiographs were retrospectively obtained from the Shriners Hospitals for Children. Demographic and radiographic features, previously reported to be associated with curve progression, were collected. Sequential Backward Floating Selection (SBFS) was used to select a subset of the most predictive features. Based on the performance of several machine learning methods, a Random Forest (RF) regressor model was used to provide the importance rank of prognostic features and to predict the final major Cobb angle., Results: The seven most predictive prognostic features in the order of importance were initial major Cobb angle, flexibility, initial lumbar lordosis angle, initial thoracic kyphosis angle, age at last visit, number of levels involved, and Risser "+" stage at the first visit. The RF model predicted the final major Cobb angle with a Mean Absolute Error (MAE) of 4.64 degrees., Conclusion: A RF model was developed and validated to identify the most important prognostic features for curve progression and predict the final major Cobb angle. It is possible to predict the final major Cobb angle value within 5 degrees error from 2D radiographic features. Such methods could be directly applied to guide intervention timing and optimization for AIS treatment., Competing Interests: The authors have declared that no competing interests exist.

Background: The outcomes of congenital scoliosis (CS) patients undergoing hemivertebra (HV) resection surgery with a 2-level fusion versus a >2-level fusion are unclear. We hypothesized that CS patients undergoing HV resection and a >2-level fusion have decreased curve progression and reoperation rates compared with 2-level fusions., Methods: Retrospective review of prospectively collected data from a multicenter scoliosis database. Fifty-three CS patients (average age 4.5, range 1.2 to 10.9 y) at index surgery were included. Radiographic and surgical parameters, complications, as well as revision surgery rates were tracked at a minimum of 2-year follow-up., Results: Twenty-six patients had a 2-level fusion while 27 patients had a >2-level fusion with similar age and body mass index between groups. The HV was located in the lumbar spine for 69% (18/26) 2-level fusions and 30% (8/27) >2-level fusions ( P =0.006). Segmental HV scoliosis curve was smaller in 2-level fusions compared to >2-level fusions preoperatively (38 vs. 50 degrees, P =0.016) and at follow-up (25 vs. 34 degrees, P =0.038). Preoperative T2-T12 (28 vs. 41 degrees, P =0.013) and segmental kyphosis (11 vs. 23 degrees, P =0.046) were smaller in 2-level fusions, but did not differ significantly at postoperative follow-up (32 vs. 39 degrees, P =0.22; 13 vs. 11 degrees, P =0.64, respectively). Furthermore, the 2 groups did not significantly differ in terms of surgical complications (27% vs. 22%, P =0.69; 2-level fusion vs. >2-level fusion, respectively), unplanned revision surgery rate (23% vs. 22%, 0.94), growing rod placement or extension of spinal fusion (15% vs. 15%, P =0.95), or health-related quality of life per the EOS-Questionnaire 24 (EOSQ-24). Comparison of patients with or without the need for growing rod placement or posterior spinal fusion revealed no significant differences in all parameters analyzed., Conclusions: Two-level and >2-level fusions can control congenital curves successfully. No differences existed in curve correction, proximal junctional kyphosis or complications between short and long-level fusion after HV resection. Both short and long level fusions are viable options and generate similar risk of revision. The decision should be individualized by patient and surgeon., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: Vertebral body tethering (VBT) continues to grow in interest from both a patient and surgeon perspective for the treatment of scoliosis. However, the data are limited when it comes to surgeon selection of both procedure type and instrumented levels. This study sought to assess surgeon variability in treatment recommendation and level selection for VBT versus posterior spinal fusion (PSF) for the management of scoliosis., Methods: Surgeon members of the Pediatric Spine Study Group and Harms Study Group were queried for treatment recommendations and proposed upper instrumented vertebra (UIV) and lower instrumented vertebra (LIV) selection for PSF and VBT based on 17 detailed clinical vignettes. Responses were subdivided in each clinical vignette according to surgeon experience and treatment recommendations with assessment of intra-rater reliability. Binomial distribution tests were used to establish equipoise, selecting p < 0.10 to indicate the presence of a treatment choice with consensus set > 70% agreement. For treatment choice, responses were assessed first for consensus on the decision to proceed with PSF or VBT., Results: Thirty-five surgeons with varied experience completed the survey with 26 surgeons (74%) completing the second follow-up survey. Overall, VBT was the recommended treatment by 47% of surgeons, ranging by clinical vignette. Consensus in treatment recommendation was present for 6 clinical vignettes including 3 for VBT and 3 for PSF, with equipoise present for the remaining 11. Of the 17 vignettes, 12 demonstrated moderate intra-observer reliability including the 3 consensus vignettes for VBT. Sanders stage ≤ 3 and smaller curve magnitude were related with VBT recommendation but neither age nor curve flexibility significantly influenced the decision to recommend VBT. Surgeons with high VBT volume, ≥ 11 VBT cases/year, were more likely to recommend VBT than those with low volumes (0-10 cases per year (p < 0.0001)). High VBT volume surgeons demonstrated consensus in VBT recommendation for Lenke 5/6 curves (75% mean recommendation). High VBT volume surgeons had a significantly higher VBT recommendation rate for Lenke 1A, 2A curves (71.8% vs 48.0%, p = 0.012), and Lenke 3 curves (62% vs 26.9%, p = 0.023). Equipoise was present for all vignettes in low volume surgeons. In addition, high VBT volume surgeons trended toward including more instrumented levels than low VBT volume surgeons (7.17 vs 6.69 levels)., Conclusion: Significant equipoise is present among pediatric spine surgeons for treatment recommendations regarding VBT and PSF. Surgeon-, patient-, and curve-specific variables were identified to influence treatment recommendations, including surgeon experience, curve subtype, deformity magnitude, and skeletal maturity. This study highlights the need for continued research in identifying the optimal indications for VBT and PSF in the treatment of pediatric spinal deformity., (© 2022. The Author(s), under exclusive licence to Scoliosis Research Society.)

Purpose: Pulmonary function and quality of life (QOL) are important outcome measures for patients with early-onset scoliosis (EOS) undergoing rib-based growing system (RBGS) implantation. The Assisted Ventilation Rating (AVR) measures ventilator requirements in this population. A higher, more severe, score implies negative changes in QOL. The EOS Questionnaire (EOSQ) is a validated outcome measure. Paired measurements for both ratings were compared to clarify correlation between ventilator status and QOL. Secondary analysis aimed at defining QOL between more broad subgroups defined by ventilator use., Methods: AVR and EOSQ scores were extracted from the Pediatric Spine Study Group database for patients 10 years of age and under. Instances were excluded if the time between AVR and EOSQ assessment was greater than 6 months. Scores were compared using Spearman correlation coefficient. Subgroup analysis included control for age, gender, and etiology. Secondary analysis was performed for broad functional grouping using ranked analysis of variance for repeated measures using median scores., Results: Two thousand five hundred and forty-two instances of paired EOSQ and AVR in 329 patients were analyzed. A statistically significant weak correlation between AVR and EOSQ was identified in Child's Health Related QOL and Family Impact sections, in nine subsets. Subgroup analysis showed little variation, except increased correlation in female patients to near moderate level. Analysis of variance for demonstrated decreased medians for all subdomains when comparing those mechanically ventilated to patients who did not require ventilation., Conclusion: Ventilator status tracks with QOL were measured by EOSQ. A more severe AVR is negatively correlated with most domains of the EOSQ for patients with EOS who have undergone RBGS implantation. The strength of this correlation is weak, and so AVR alone may be insufficient to precisely determine QOL in this population., Level of Evidence: Level-III, Retrospective., (© 2022. The Author(s), under exclusive licence to Scoliosis Research Society.)

Study Design: Prospective multicenter international observational study., Objective: To investigate the effect of implant density on clinical outcomes in complex pediatric spine reconstruction. Implant density in spine deformity surgery has been a subject of much debate with some authors advocating higher density for better correction. Few studies have looked at the effect of implant density on severe curves > 100 deg or treated with vertebral column resection (VCR)., Methods: 250/311 pts with 2-year f/u enrolled in the FOX pediatric database from 17 international sites were queried for the impact of implant density and surgical outcomes. Patients were grouped into three implant density categories for comparative analysis Group 1 (density ≤ 1), Group 2 (1 < density < 1.5) and Group 3 (density; 1.5-2)., Results: 250 pts: 47 (Grp1)/99 (Grp2) /104 (Grp3); Pre-op age and etiology and curve types were similar in all groups, but body mass index (BMI) was higher in Grp3. Grps 1 and 2 had significantly higher sagittal deformity angular ratio (S-DAR) compared to Grp 3 (p < 0.001). Pre-op Halo Gravity Traction (HGT) was used in 55.3%/44.4%/31.7%, p = 0.017; Grp1/Grp2/Grp3, respectively. Average duration of surgery (min) was higher in Grp3 relative to Grp1 only: 352.5/456.5/515.0, p = 0.0029. Blood loss was similar in all Grps. Rate of VCR, PSO and SPO was similar in all Grps. Pre-op Coronal Cobb avg 96.1/83.6/88.6, p = 0.2342, attained similar correction after HGT (24.6%/27.2%/23.2%, p = 0.4864. Coronal Cobb corrections at 2-year follow-up (FU) were (37.1%/40.3%/53.5%, p = 0.0004). Pre-op sagittal Cobb was (105.4/101.9/75.9, p < 0.01.), achieved similar %correction in HGT (19.1%/22.3%/22.5%, p = 0.6851) and at 2-year FU (39.6%/41.4%/29.8%, p = 0.1916). After adjusting for C-DAR, S-DAR, pre-op coronal and sagittal Cobb, etiology, curve types, age, BMI and number of rods in multivariate analysis, the odds of developing post-operative implant complication was 11 times greater in group 1 compared to group 3 (OR = 11.17,95% CI 2.34-53.32). There was significant improvement in SRS scores in all Grps at 2-year FU., Conclusion: Although higher implant density was observed to be associated with greater curve correction and lower rates of post-operative implant-related complication and revision in heterogeneous case groups, the results may not imply causality of implant density on the outcomes in severe pediatric spine reconstruction., (© 2022. The Author(s), under exclusive licence to Scoliosis Research Society.)

Objective: Neurofibromatosis type 1 (NF1) dystrophic scoliosis is an early-onset, rapidly progressive multiplanar deformity. There are few studies on the surgical management of this patient population. Specifically, perioperative morbidity, instrument-related complications, and quality-of-life outcomes associated with surgical management have not been systematically evaluated. In this study, the authors aimed to perform a systematic review on the natural history, management options, and surgical outcomes in patients who underwent NF1 dystrophic scoliosis surgery., Methods: A PubMed search for articles with "neurofibromatosis" and either "dystrophic" or "scoliosis" in the title or abstract was performed. Articles with 10 or more patients undergoing surgery for NF1 dystrophic scoliosis were included. Data regarding indications, treatment details, morbidity, and outcomes were summarized and analyzed with descriptive statistics., Results: A total of 310 articles were identified, 48 of which were selected for full-text review; 30 studies describing 761 patients met the inclusion criteria. The mean age ranged from 7 to 22 years, and 99.7% of patients were younger than 18 years. The mean preoperative coronal Cobb angle was 75.2°, and the average correction achieved was 40.3°. The mean clinical follow-up in each study was at least 2 years (range 2.2-19 years). All patients underwent surgery with the intent of deformity correction. The scoliosis regions addressed were thoracic curves (69.6%) and thoracolumbar (11.1%) and lumbar (14.3%) regions. The authors reported on a variety of approaches: posterior-only, combined anterior-posterior, and growth-friendly surgery. For fixation techniques, 42.5% of patients were treated with hybrid constructs, 51.5% with pedicle screw-only constructs, and 6.0% with hook-based constructs. Only 0.9% of patients underwent a vertebral column resection. The nonneurological complication rate was 14.0%, primarily dural tears and wound infections. The immediate postoperative neurological deficit rate was 2.1%, and the permanent neurological deficit rate was 1.2%. Ultimately, 21.5% required revision surgery, most commonly for implant-related complications. Loss of correction in both the sagittal and coronal planes commonly occurred at follow-up. Five papers supplied validated patient-reported outcome measures, showing improvement in the mental health, self-image, and activity domains., Conclusions: Data on the surgical outcomes of dystrophic scoliosis correction are heterogeneous and sparse. The perioperative complication rate appears to be high, although reported rates of neurological deficits appear to be lower than clinically observed and may be underreported. The incidence of implant-related failures requiring revision surgery is high. There is a great need for multicenter prospective studies of this complex type of deformity.

Background: While largely of concern in nonambulatory patients, pelvic obliquity (PO) can be found in many patients with early onset scoliosis (EOS) and may remain following surgery. However, its association with health-related quality of life (HRQoL) in children and their caregivers at the end of treatment is not well understood. The purpose of this study was to investigate the association between residual PO and HRQoL in children and their caregivers at the end of surgical treatment in ambulatory patients with EOS., Methods: In this retrospective cohort study, a multicenter EOS registry was queried to identify ambulatory patients who underwent definitive posterior spinal fusion (PSF) from 2012 to 2019. Patients with fusions extending to the pelvis were excluded. PO was measured at least 1 year following PSF. HRQoL, Parental Burden, Financial Burden, and Satisfaction were assessed through the 24-Item Early Onset Scoliosis Questionnaire (EOSQ-24) also at a minimum of 1 year following PSF., Results: A total of 155 patients (12.5±2.1 y, 73.5% female) were included. Etiology distribution was 30.3% congenital, 12.9% neuromuscular, 21.3% syndromic, and 35.5% idiopathic. In congenital patients, those with residual PO >8 degrees had worse Satisfaction by 23.2 points compared with those with PO ≤8 degrees. In neuromuscular patients, those with residual PO >7 degrees had worse HRQoL by 16.1 points and Parental Burden by 22.3 points compared with their counterparts. In syndromic patients, those with residual PO >8 degrees had worse HRQoL by 14.8 points, Parental Burden by 16.4 points, and Satisfaction by 21.2 points compared with their counterparts. In idiopathic patients, those with >9 degrees of residual PO had worse HRQoL by 15.0 points and Financial Burden by 26.8 points compared with their counterparts., Conclusions: Remaining PO at the end of surgical treatment is associated with worse HRQoL in ambulatory children and their caregivers. These results suggest that correction of PO should remain a primary goal of treatment in patients with EOS undergoing surgery., Level of Evidence: Level II-multicenter retrospective cohort study investigating prognosis., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: In adolescent idiopathic scoliosis (AIS), the rib prominence is a major cosmetic concern which can be improved using thoracoplasties. We sought to determine if the use of deep drains helps minimize the development of pleural effusions after thoracoplasties., Methods: Retrospective study of 45 patients with AIS undergoing posterior spinal fusion (PSF) and thoracoplasties., Results: Thirty six out of 45 patients (80.0%) required placement of a deep surgical drain, and 16 out of 45 (35.6%) developed pleural effusions after PSF with concomitant thoracoplasty. Of the 16 patients who developed pleural effusion, 12 of 36 (33.3%) required a placement of a deep drain (p > 0.05). Of the total 45 patients in this cohort, 3 patients (6.7%) required chest tubes, and 4 patients (8.9%) developed surgical site infections (SSIs). We found that deep drains were associated with a lower incidence of SSI (2.8% vs 33.3%; p = 0.021). Patients who had a pleural effusion had longer ICU stays (p = 0.037) and longer requirements of nasal oxygen (p = 0.025)., Discussion: The presence of a pleural effusion in patients with AIS undergoing PSF with thoracoplasty was associated with longer oxygen requirements and length of hospital ICU admission. Thirty six percent of patients with thoracoplasties developed pleural effusions, but deep subfascial drains did not significantly decrease the incidence of pleural effusions., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Study Design: Retrospective review of prospective data from multicenter registry., Objective: Compare outcomes of posterior spinal fusion (PSF) versus magnetically controlled growing rods (MCGR) versus vertebral body tethers (VBT) in 8- to 11-year-old idiopathic early onset scoliosis (EOS) patients., Summary of Background Data: In EOS, it is unclear at what age the benefit of growth-sparing strategies outweighs increased risks of surgical complications, compared with PSF., Methods: One hundred thirty idiopathic EOS patients, 81% female, aged 8-11 at index surgery (mean 10.5 yrs), underwent PSF, MCGR, or VBT. Scoliosis curve, kyphosis, thoracic and spinal height, complications, and Quality of Life (QoL) were assessed preoperatively and at most recent follow-up (prior to final fusion for VBT/MCGR)., Results: Of 130 patients, 28.5% received VBT, 39.2% MCGR, and 32.3% PSF. The VBT cohort included more females (P < 0.0005), was older (P < 0.0005), more skeletally mature (P < 0.0005), and had smaller major curves (P < 0.0005). At follow-up, scoliosis curve corrected 41.1 ± 22.4% in VBT, 52.2 ± 19.9% in PSF, and 27.4 ± 23.9% in MCGR (P < 0.0005), however, not all VBT/MCGR patients finished treatment. Fifteen complications occurred in 10 VBTs, 6 requiring unplanned surgeries; 45 complications occurred in 31 MCGRs, 11 requiring unplanned surgeries, and 9 complications occurred in 6 PSFs, 3 requiring unplanned revisions. Cox proportional hazards regression adjusted for age, gender, and preoperative scoliosis curve revealed that MCGR (hazard ratio [HR] = 21.0, 95% C.I. 4.8-92.5; P < 0.001) and VBT (HR = 7.1, 95% C.I. 1.4-36.4; P = 0.019) patients were at increased hazard of requiring revision, but only MCGR patients (HR = 5.6, 95% C.I. 1.1-28.4; P = 0.038) were at an increased hazard for unplanned revisions compared with PSF. Thoracic and spinal height increased in all groups. QoL improved in VBT and PSF patients, but not in MCGR patients., Conclusion: In older idiopathic EOS patients, MCGR, PSF, and VBT controlled curves effectively and increased spinal height. However, VBT and PSF have a lower hazard for an unplanned revision and improved QoL.Level of Evidence: 3., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Background Context: Since the study of Thompson, et al in 2005, use of dual-growing rod constructs have become the gold standard for operative treatment in early-onset scoliosis. However, use of dual-growing rod constructs may not be possible, due to patient size and the type, location and severity of the spinal deformity., Purpose: The purpose of this study is to: (1) describe the deformities treated with single-growing rod constructs, and (2) report the outcomes of single-growing rods since 2005., Study Design: Observational, descriptive case series METHODS: A prospective, multi-center, international database of early-onset scoliosis patients were queried to identify all patients with single traditional growing rods (sTGR) or magnetically-controlled growing rods (sMCGR) since the 2005. Patients were excluded if there were greater than 1 rod or if there was less than 2 years of follow-up postoperatively. Twenty-five patients (13 female, 12 male) were identified from the database query, which satisfied the inclusion and exclusion criteria., Results: Mean age at index surgery was 4.7 years (1.3 to 9.3 years) and mean follow-up was 4.3 years (2.0 to 10.6 years). Eleven patients were classified as congenital (all mixed-type), six neuromuscular, five idiopathic and three syndromic. Proximal foundations were ribs in 23 patients and pedicle screws in two patients. The distal foundations were the spine in 25 patients and three pelvic S-hooks. All single rods were on the concave side of the deformity. Interpretation of preoperative radiographs determined in 72% (18/25) of cases dual growing rods would be difficult and/or suboptimal due to patient size (longitudinal a/o weight) and/or kyphosis/kyphoscoliosis with severe rotation. Maximal coronal deformity improved 30% (83.9 degrees to 58.6 degrees) at latest follow-up. Maximal kyphosis increased 17% (45.6 degrees to 57.4 degrees). Postoperative length increase: T1-T12, 17.0 mm (4.6 mm/year); T1-S1, 34 mm (9.4 mm/year). Total secondary surgeries for TGRs were 100: 66 lengthenings, 32 revisions, two unknown. 10 MCGRs secondary surgeries occurred in nine patients (seven for maximized actuators and three for foundation migration). At latest follow-up 20 continued with lengthenings (five TGR & 15 MCGR), four underwent definitive fusions, and one completed lengthening (implants retained)., Conclusions: Treatment of severe EOS with single rods demonstrated a 30% coronal correction. T1-S1 length increased at 9.4 mm/year and T1-T12 length at 4.6 mm/year, which are comparable to published reports on dual MCGRs. Single TGRs and MCGRs in EOS can provide acceptable short-term outcomes when dual rods are not deemed appropriate., Clinical Significance: The use of single growing rod constructs, in the 4-8 years old patient with EOS, can achieve reasonable short-term radiographic outcomes., (Copyright © 2021 Elsevier Inc. All rights reserved.)

Vertebral body tethering is a nonfusion technique for the surgical correction of adolescent idiopathic scoliosis. For skeletally immature patients for whom vertebral body tethering is indicated, it is an alternative option to the gold standard posterior spinal fusion (PSF) and may at least partially preserve motion in instrumented segments of the spine. Benefits of the procedure include the possibility of avoiding the long-term sequelae of PSF such as adjacent segment disease and proximal junctional kyphosis. Recent retrospective case series of vertebral body tethering have shown promising results with correction rates up to 70% but greater variability in outcomes compared with PSF. The complication profile of the procedure also appears to differ from PSF with tether breakage and overcorrection as primary concerns in addition to approach-related complications. Although early outcomes have been promising, additional studies to optimize surgical timing, long-term outcomes, and the possible role of tethering in the more skeletally mature patient are required.

Purpose: Determine the efficacy of intraoperative traction (IOT) on curve correction in AIS., Methods: A prospective, multicenter, longitudinal database identified patients with major thoracic AIS (Lenke 1-4) treated with surgery using IOT and follow-up of 2 years. These cases were matched to comparable cases treated without traction (non-IOT). All patients were treated with single-stage posterior only surgery with pedicle screw constructs. Perioperative, radiographic and clinical outcome data at 2 years post-op were compared between the groups., Results: 104 cases treated with IOT were matched to 104 treated without IOT. Operating room time was significantly greater in the IOT group (339 vs. 306 min, p =  < 0.001). Neuromonitoring alerts were more frequent in the IOT group (23% vs. 5%, p < 0.001). There were no postoperative neurological deficits in either group. The IOT group showed significantly greater MT curve correction (IOT 71% vs. non-IOT 66.7%, p < 0.003), with the effect most pronounced in curves > 70° (IOT 72% vs. non-IOT 64%, p = 0.04). IOT was associated with a significant reduction in 2D T5-T12 kyphosis measurements (IOT - 6.5° vs non-IOT + 0.48°, p < 0.001), yet significant improvements in estimated 3D thoracic kyphosis were made in both groups, with the non-IOT group making greater improvement when compared to the IOT group (IOT + 18.1° vs. non-IOT + 22.3° vs., p = 0.008)., Conclusions: IOT is associated with modestly enhanced coronal deformity correction. Surgeons should be aware of the increased rates of neuromonitoring alerts when using this technique and its affect on the sagittal profile. Given this IOT may be best suited to larger curves., Level of Evidence: 3., (© 2021. Scoliosis Research Society.)

Study Design: Retrospective, multicenter comparative., Objectives: Our purpose was to compare early onset scoliosis (EOS) patients treated with ultra-low, low, and high implant density constructs when undergoing conversion to definitive fusion. Larson et al. demonstrated that implant density (ID) at fusion does not correlate with outcomes in the treatment of adolescent idiopathic scoliosis, but did not address growth-friendly graduates., Methods: EOS patients treated with growth-friendly constructs converted to fusion between 2000 and 2017 were reviewed from a multicenter database. ID was defined as number of pedicle screws, hooks, and sublaminar/bands per level fused. Patients were divided into ultra-low ID (< 1.3), low (≥ 1.3 and < 1.6), and high ID (≥ 1.6)., Exclusion Criteria: < 2 years follow-up from fusion or inadequate radiographs., Results: A total of 152 patients met inclusion criteria with 39 (26%) patients in the high ID group, 33 (22%) patients in the low ID group, and 80 (52%) in the ultra-low ID group. Groups were similar in operative time (p = 0.61), pre-fusion major curve (p = 0.71), mean number of levels fused (p = 0.58), clinical follow-up (p = 0.30), and radiographic follow-up (p = 0.90). Patients in the low ID group (11.6 ± 1.5 years) were slightly younger at the time of definitive fusion than patients in the ultra-low ID group (12.9 ± 2.2 years) and high ID group (12.5 ± 1.7 years) (p = 0.009). There was significantly more blood loss in the high ID group than the other two groups (high ID: 946.8 ± 606.0 mL vs. low ID: 733.9 ± 434.5 mL and ultra-low ID: 617.4 ± 517.2 mL; p = 0.01), but there was no significant difference with regard to percent of total blood volume lost (high ID: 59.3 ± 48.7% vs. low ID: 54.5 ± 37.5% vs. ultra-low ID: 51.7 ± 54.9%; p = 0.78). There was a difference in initial improvement in major curve between the groups (high ID: 21.6° vs. low ID: 18.0° vs. ultra-low ID: 12.6°; p = 0.01). However, during post-fusion follow-up, correction decreased 7.1° in the high ID group, 2.6 in the low ID group, and 2.8 in the ultra-low ID group (p = 0.19). At final follow-up, major curve correction from pre-fusion was similar between groups (high ID: 14.5° vs. low ID: 15.5° vs. ultra-low ID: 9.7°, p = 0.14). At final follow-up, there was no difference in T1-T12 length gain (p = 0.85), T1-S1 length gain (p = 0.68), coronal balance (p = 0.56), or sagittal balance (p = 0.71). The revision rate was significantly higher in the ultra-low ID group (13.8%; 11/80) versus the high ID group (2/39; 5.1%) and low ID group (0/33; 0%) (p = 0.04)., Conclusions: Although an ID < 1.3 in growth-friendly graduates produces similar outcomes with regard to curve correction and spinal length gain as low and high ID, this study suggests that an ID < 1.3 is associated with an increased revision rate., Level of Evidence: III., (© 2021. Scoliosis Research Society.)

Background: Anterior vertebral body tethering (aVBT) has emerged as a novel treatment option for patients with idiopathic scoliosis. We present the results from the first U.S. Food and Drug Administration (FDA) Investigational Device Exemption (IDE) study on aVBT., Methods: In this prospective review of a retrospective data set, eligible patients underwent aVBT at a single center from August 2011 to July 2015. Inclusion criteria included skeletally immature patients with Lenke type-1A or 1B curves between 30° and 65°. Clinical and radiographic parameters were collected, with the latter measured by an independent reviewer., Results: Fifty-seven patients (49 girls and 8 boys), with a mean age (and standard deviation) of 12.4 ± 1.3 years (range, 10.1 to 15.0 years), were enrolled in the study. The patients had a mean of 7.5 ± 0.6 levels tethered, the mean operative time was 223 ± 79 minutes, and the mean estimated blood loss was 106 ± 86 mL. The patients were followed for an average of 55.2 ± 12.5 months and had a mean Risser grade of 4.2 ± 0.9 at the time of the latest follow-up. The main thoracic Cobb angle was a mean of 40.4° ± 6.8° preoperatively and was corrected to 18.7° ± 13.4° at the most recent follow-up. In the sagittal plane, T5-T12 kyphosis measured 15.5° ± 10.0° preoperatively, 17.0° ± 10.1° postoperatively, and 19.6° ± 12.7° at the most recent follow-up. Eighty percent of patients had curves of <30° at the most recent follow-up. The most recent Scoliosis Research Society (SRS) scores averaged 4.5 ± 0.4, and scores on the self-image questionnaire averaged 4.4 ± 0.7. No major neurologic or pulmonary complications occurred. Seven (12.3%) of 57 patients had a revision: 5 were done for overcorrection and 2, for adding-on., Conclusions: Anterior VBT is a promising technique that has emerged as a treatment option for patients with immature idiopathic scoliosis. We present the results from the first FDA-approved IDE study on aVBT, which formed the basis for the eventual Humanitarian Device Exemption approval. The findings affirm the safety and efficacy of this technique and suggest opportunities for improvement, particularly with respect to reoperation rates., Level of Evidence: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence., Competing Interests: Disclosure: The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article (http://links.lww.com/JBJS/G589)., (Copyright © 2021 by The Journal of Bone and Joint Surgery, Incorporated.)

Study Design: Retrospective review of a prospectively collected multicenter database., Objectives: To identify risk factors for early and late readmission of surgically treated patients with adolescent idiopathic scoliosis (AIS). Specific risk factors associated with readmission in patients with AIS remain poorly understood., Methods: Patients with AIS who were operatively treated from 19 centers specializing in the treatment of pediatric spinal deformity were studied. Data from a minimum 2 years of clinical follow-up and any readmission were available for analysis. Characteristics of patients with no readmission, early readmission (< 90 days), and late readmission (> 90 days) were evaluated. Both univariate and multivariate analyses of risk factors for readmission were performed., Results: 2049 patients were included in our cohort, with 1.6% requiring early readmission and 3.3% late readmission. In the multivariate analysis, greater preoperative coronal imbalance was associated with early readmission. Longer operative time was associated with late readmission. Finally, greater preoperative pain (SRS-22 pain scale) was associated with both early and late readmission. GI complications accounted for a higher proportion of early readmissions than previously reported in the literature., Conclusions: Preoperative counseling of patients with higher levels of pain and coronal imbalance and the implementation of a thorough postoperative bowel regimen may help optimize patient outcomes., Level of Evidence: 3., (© 2021. Scoliosis Research Society.)

Purpose: Proximal instrumentation failure is a challenge in posterior spinal fusions (PSFs) crossing the cervicothoracic junction. High rates of proximal junctional kyphosis (PJK) and loss of fixation have been reported. In this single-center retrospective cohort study, we evaluate the utility of anterior cervical discectomy and fusion (ACDF) in addition to traditional PSF crossing the cervicothoracic junction in order to mitigate implant-related complications., Methods: All patients who underwent PSF across the cervicothoracic junction with ACDF with 2 years of follow-up data were reviewed. We analyzed clinical, surgical, and radiographic measures such as operative details, presence of PJK, complications, instrumentation migration, curve angles, and vertebral translation. Measurements were compared statistically using paired samples t-tests., Results: Ten patients (6 girls, 4 boys) met inclusion criteria with a mean age at surgery of 12.8 ± 3.3 years and follow-up of 3.38 ± 0.9 years. All patients underwent ACDF (range 1-3 levels), and 8 (80%) underwent traction. The average number of levels fused posteriorly was 16.7 ± 4.7 and anteriorly was 2.4 ± 0.7. The major coronal curve averaged 48.8 ± 34.7° preoperatively and 23.3±13.3° postoperatively (p = 0.028). The average major sagittal curve was 83.5 ± 24.2° preoperatively, resolving to 53.9 ± 25.5° (p=0.001). One patient suffered rod breakage at T7, and another developed symptomatic PJK 19 months postoperatively., Conclusion: Our data suggest that ACDF procedures added to PSFs crossing the cervicothoracic junction offer promise for reducing risk for instrumentation-related complications. ACDF also significantly helps improve and maintain both coronal and sagittal correction over 2 years., Level of Evidence: 4.

Background: It is unclear whether the type of proximal anchor affects the spine length achieved with distraction-based surgeries in patients with nonidiopathic early-onset scoliosis (EOS). Since distraction may produce kyphosis, spine length should be assessed in the sagittal plane using the sagittal spine length (SSL-curved arc length of the spine in the sagittal plane). Our purpose was to determine if the type of proximal anchor in distraction-based surgeries will affect final spine length., Methods: Patients with nonidiopathic EOS treated with distraction-based systems (minimum 5 y follow-up, 5 lengthenings) were identified from 2 EOS registries. Radiographic analysis preoperative, postimplant (L1), and after each lengthening (L2-L5, L6-L10, L11-L15) was performed with the primary outcome of T1-S1 SSL., Results: We identified 126 patients-70 had rib-based implants (52 congenital, 9 syndromic, 9 neuromuscular) and 56 had spine-based implants (15 congenital, 29 syndromic, 12 neuromuscular) with preoperative age 4.6 years, scoliosis 75 degrees, and kyphosis 48 degrees. After initial correction (P<0.05), scoliosis remained constant [58 degrees (13 to 104 degrees) at L11-L15] and kyphosis increased over time [38 degrees (9 to 108 degrees) at L1 to 60 degrees (17 to 134 degrees) at L11-L15] (P<0.05). Preoperative SSL was higher in the spine-based group (29.6 cm) when compared with the rib-based group (25.2 cm) (P<0.05). This difference was maintained after initial implantation (spine-based: 32.2 cm vs. rib-based: 26.7 cm, P<0.05) and at final follow-up (spine-based: 37.0 cm vs. rib-based: 34.4 cm, P<0.05). As preoperative SSL differed between groups, maximum SSL gains per interval were also normalized to preoperative SSL. There was no statistically significant difference between groups at L1, L2-L5, and L6-L10. However, at L11-L15, the rib-based group achieved a more relative increase in spine length compared with the spine-based group (45% vs. 31%, P<0.05)., Conclusion: At minimum 5 year follow-up, distraction-based surgeries increased spine length for patients with nonidiopathic EOS; regardless of proximal anchor type., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)

Objective: Spontaneous lumbar curve correction after selective thoracic fusion in surgery for adolescent idiopathic scoliosis (AIS) is well described. However, only a few articles have described the course of the uninstrumented upper thoracic (UT) curve after fusion, and the majority involve a hybrid construct. In this study, the authors sought to determine the outcomes and associated factors of uninstrumented UT curves in patients with AIS., Methods: The authors retrospectively reviewed a prospectively collected multicenter AIS registry for all consecutive patients with Lenke type 1-4 curves with a 2-year minimum follow-up. UT curves were considered uninstrumented if the upper instrumented vertebra (UIV) did not extend above 1 level from the lower end vertebra of the UT curve. The authors defined progression as > 5°, and divided patients into two cohorts: those with improvement in the UT curve (IMP) and those without improvement in the UT curve (NO IMP). Radiographic, demographic, and Scoliosis Research Society (SRS)-22 survey outcome measures were compared using univariate analysis, and significant factors were compared using a multivariate regression model., Results: The study included 450 patients (370 females and 80 males). The UT curve self-corrected in 86% of patients (n = 385), there was no change in 14% (n = 65), and no patients worsened. Preoperatively, patients were similar with respect to Lenke classification (p = 0.44), age (p = 0.31), sex (p = 0.85), and Risser score (p = 0.14). The UT curves in the IMP group self-corrected from 24.7° ± 6.5° to 12.6° ± 5.9°, whereas in the NO IMP group UT curves remained the same, from 20.3° ± 5.8° to 18.5° ± 5.7°. In a multivariate analysis, preoperative main thoracic (MT) curve size (p = 0.004) and MT curve correction (p = 0.001) remained significant predictors of UT curve improvement. Greater correction of the MT curve and larger initial MT curve size were associated with greater likelihood of UT curve improvement., Conclusions: Spontaneous UT curve correction occurred in the majority (86%) of unfused UT curves after MT curve correction in Lenke 1-4 curve types. The magnitude of preoperative MT curve size and postoperative MT curve correction were independent predictors of spontaneous UT curve correction.

Background: Arthrogryposis multiplex congenita (AMC) is a condition that describes neonates born with ≥2 distinct congenital contractures. Despite spinal deformity in 3% to 69% of patients, inadequate data exist on growth-friendly instrumentation (GFI) in AMC. Our study objectives were to describe current GFI trends in children with AMC and early-onset scoliosis (EOS) and to compare long-term outcomes with a matched idiopathic EOS (IEOS) cohort to determine whether spinal rigidity or extremity contractures influenced outcomes., Methods: Children with AMC and spinal deformity of ≥30° who were treated with GFI for ≥24 months were identified from a multicenter EOS database (1993 to 2017). Propensity scoring matched 35 patients with AMC to 112 patients with IEOS with regard to age, sex, construct, and curve. Multivariable linear mixed modeling compared changes in spinal deformity and the 24-item Early Onset Scoliosis Questionnaire (EOSQ-24) across cohorts. Cohort complications and reoperations were analyzed using multivariable Poisson regression., Results: Preoperatively, groups did not differ with regard to age (p = 0.87), sex (p = 0.96), construct (p = 0.62), rate of nonoperative treatment (p = 0.54), and major coronal curve magnitude (p = 0.96). After the index GFI, patients with AMC had reduced percentage of coronal correction (35% compared with 44%; p = 0.01), larger residual coronal curves (49° compared with 42°; p = 0.03), and comparable percentage of kyphosis correction (17% compared with 21%; p = 0.52). In GFI graduates (n = 81), final coronal curve magnitude (55° compared with 43°; p = 0.22) and final sagittal curve magnitude (47° compared with 47°; p = 0.45) were not significantly different at the latest follow-up after definitive surgery. The patients with AMC had reduced T1-S1 length (p < 0.001), comparable T1-S1 growth velocity (0.66 compared with 0.85 mm/month; p = 0.05), and poorer EOSQ-24 scores at the time of the latest follow-up (64 compared with 83 points; p < 0.001). After adjusting for ambulatory status and GFI duration, patients with AMC developed 51% more complications (incidence rate ratio, 1.51 [95% confidence interval (CI), 1.11 to 2.04]; p = 0.009) and 0.2 more complications/year (95% CI, 0.02 to 0.33 more; p = 0.03) compared with patients with IEOS., Conclusions: Patients with AMC and EOS experienced less initial deformity correction after the index surgical procedure, but final GFI curve magnitudes and total T1-S1 growth during active treatment were statistically and clinically comparable with IEOS. Nonambulatory patients with AMC with longer GFI treatment durations developed the most complications. Multidisciplinary perioperative management is necessary to optimize GFI and to improve quality of life in this complex population., Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence., Competing Interests: Disclosure: The authors indicated that no external funding was received for any aspect of this work. On the Disclosure of Potential Conflicts of Interest forms, which are provided with the online version of the article, one or more of the authors checked “yes” to indicate that the author had a relevant financial relationship in the biomedical arena outside the submitted work and “yes” to indicate that the author had other relationships or activities that could be perceived to influence, or have the potential to influence, what was written in this work (http://links.lww.com/JBJS/G318)., (Copyright © 2021 by The Journal of Bone and Joint Surgery, Incorporated.)

Introduction: The incidence of neurologic complications with spinal surgery for adolescent idiopathic scoliosis (AIS) has been reported to be 0.69%. This rare complication typically occurs during surgery or immediately postoperatively. We report the occurrence of a delayed neurologic deficit that presented 36 h after the initial surgery of a staged posterior spinal fusion for severe AIS., Case Presentation: A 12-year-old girl with severe thoracolumbar AIS of 125° underwent attempted posterior spinal fusion from T2-L4. The case was complicated by a transient loss of transcutaneous motor evoked potentials (TcMEP) that resolved with an increase in the mean arterial pressure (MAP) and relaxation of curve correction with rod removal. The patient awoke with normal neurologic function. She had a transient decrease in MAP 36 h post-op and awoke on postoperative day #2 with nearly complete lower extremity paraplegia (American Spinal Injury Association [ASIA] Impairment Scale B). Emergent exploration and removal of the concave apical pedicles resulted in improvement of TcMEPs and return of function., Discussion: Delayed postoperative neurologic deficit is a very rare phenomenon, with only a few case reports in the literature to date. The delayed neurologic decline of our patient was likely secondary to a transient episode of postoperative hypotension combined with spinal cord compression by the apical concave pedicles. Close monitoring and support of spinal cord perfusion as well as emergent decompression are imperative in the setting of a delayed neurologic deficit. Further multicenter study on this rare occurrence is underway to identify potential causes and improve treatment.

Study Design: Longitudinal., Objectives: To evaluate whether the rate of patients who report low health-related quality of life (HRQOL) scores at 2 years following surgical correction of adolescent idiopathic scoliosis (AIS) improves by 5 years postoperatively., Summary of Background Data: HRQOL scores are dependent upon a number of factors and even in instances of good surgical correction of a spinal deformity, are not guaranteed to be high postoperatively. Understanding how a low HRQOL score varies over the postoperative period can help surgeons more effectively counsel patients and temper expectations., Methods: A multicenter database was reviewed for patients with both 2 and 5-year follow-up after spinal fusion and instrumentation for AIS. From a cohort of 916 patients, 52 patients with low HRQOL scores at their 2-year follow-up were identified and reevaluated at 5-year follow-up. A low HRQOL outcome was defined as having SRS-22 domain or total scores less than 2 standard deviations below the mean score. Reoperations were also evaluated to determine if they were associated with HRQOL scores., Results: Of those patients with low SRS-22 HRQOL scores at 2 years postoperatively, improvements were seen in all SRS-22 domains and total scores at the 5-year time point. The greatest change was seen in the satisfaction category where 41 patients showed improvement. The rate of reoperations during this period did not significantly impact patient-reported outcomes., Conclusions: Having a low HRQOL score 2 years after surgery for AIS does not guarantee a low score 5 years after surgery. Promisingly, most patients demonstrate some improvement in all domains for patient-reported SRS-22 scores at 5-year compared to 2-year follow-up. Understanding the longer term postoperative evolution in patient-reported outcomes may help surgeons to effectively manage and counsel patients who are dissatisfied in the short term.Level of Evidence: 3., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: Karol et al. introduced the concept that 18 cm thoracic height is the critical point where a patient with early onset scoliosis (EOS) can maintain adequate pulmonary function. Our purpose was to determine if distraction-based surgeries will increase thoracic spine height to at least 18 cm in patients with EOS., Methods: Patients with EOS treated with distraction-based systems (minimum 5 years follow up, minimum five lengthenings). Radiographic analysis of thoracic spine height (T1-T12) at the last lengthening procedure., Results: One hundred and fifty-three patients (67 congenital, 21 neuromuscular, 38 syndromic, 27 idiopathic) with pre-operative mean age 4.6 years, scoliosis 75°, kyphosis 47° were evaluated. Their mean age at final lengthening procedure was 11 years (6-16), average number of lengthening procedures was 10.5 (4-21), mean final scoliosis was 53°, and mean final kyphosis was 58°. Final thoracic height was > 18 cm in 65% and was > 22 cm in 31% of patients. Based on etiology, only 48% of the congenital patients reached 18 cm compared to 81% neuromuscular, 84% syndromic and 67% idiopathic. This height gain was closely related to the percentage of scoliosis correction achieved for each etiology. Comparing congenital etiology to other etiologies, there was a lower percentage of patients in the congenital group that passed the 18 cm threshold (48% vs. 78%) (p < 0.05)., Conclusion: At minimum 5 years follow up, distraction-based surgeries increased thoracic height for patients with EOS to greater than 18 cm in 65% of patients; however, only 48% of congenital patients reached this thoracic height threshold., Design: Retrospective review of prospectively collected registry data. LOI III.

Introduction: Surgical treatment of Adolescent Idiopathic Scoliosis (AIS) involves healthy individuals with spinal deformity. Parents are responsible for surgical consent on behalf of their children, a burden which causes trepidation and concern. Therefore, explanation of operative risk is a critical component of informed consent and parent decision-making. We set out to quantify parental risk aversion (RA)., Methods: RA questionnaires were administered preoperatively to parents of 58 AIS patients undergoing spinal fusion (SF). RA is the likelihood of a parent to consent to their child's SF (1- least likely, 10- most) with increasing allotments of data about potential complications at each stage (S1-complication named, S2-explained, S3-incidence given, S4-all information). A statistically significant mean difference in answers for each stage was assessed using paired sample t test or Wilcoxon rank t test. Normality was assessed by performing Shapiro-Wilk test., Results: AIS patients (age 14.2 years, 85% female, major curve 61°) were included. Mean scores for each of the stages were 4.4 ± 3.1, 4.9 ± 3.1, 6.5 ± 3.0, 6.6 ± 3.0, respectively. Highest and lowest RA were reported for death and infection, respectively. The greatest increase in likelihood to proceed with surgery was seen after education on malposition of implants and on death, 2.6 and 2.5, respectively (p < 0.001). The lowest increase in likelihood to proceed with surgery was seen after education on infection, 1.5 (p < 0.001). For all complications, there was an increase in parent willingness to proceed after providing descriptions and occurrence rate with a mean increase from S1 to S4 of 2.1 (95% CI 1.4-2.4), p < 0.001., Conclusion: As more detailed information was made available regarding potential complications with SF for AIS, parental RA toward surgery decreased and their willingness to proceed with surgery for their child improved.

Background: There are few reports on the surgical management of early-onset scoliosis (EOS) associated with Marfan syndrome (MFS). Affected patients tend to have more rapid curve progression than those with idiopathic EOS, and their course is further complicated by medical comorbidities. As surgical techniques and implants for growing spines become more widely applied, this study seeks to better delineate the safety and efficacy of growth-friendly spinal instrumentation in treating this population., Methods: A prospective registry of children treated for EOS was queried for MFS patients treated between 1996 and 2016. Forty-two patients underwent rib-based or spine-based growing instrumentation and were assessed on preoperative, surgical, and postoperative clinical and radiographic parameters including complications and reoperations. Subgroup analysis was performed based on spine-based versus rib-based fixation., Results: Patients underwent their index surgery at a mean age of 5.5 years, when the major coronal curve and kyphosis measured 77 and 50 degrees, respectively. Over half were treated with traditional growing rods. Patients underwent 7.2 total surgical procedures-4.7 lengthening and 1.9 revision surgeries not including conversion to fusion-over a follow-up of 6.5 (±4.1) years. Radiographic correction was greatest at index surgery but maintained over time, with a final thoracic height measuring 23.8 cm. Patients experienced a mean of 2.6 complications over the course of the study period; however, a small group of 6 patients experienced ≥6 complications while over half of patients experienced 0 or 1. Implant failures represented 42% of all complications with infection and pulmonary complications following., Conclusions: This is the largest report on patients with EOS and MFS. All subtypes of growth-friendly constructs reduced curve progression in this cohort, but complications and reoperations were nearly universal; patients were particularly plagued by implant failure and migration. Further collaborations are needed to enhance understanding of optimal timing and fixation constructs for those with MFS and other connective tissue diseases., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Congenital cervical scoliosis is rare, and there is a paucity of literature describing surgical outcomes. We report surgical outcomes in a 17-patient cohort with surgical correction for congenital cervical scoliosis and identify risk factors associated with complications., Methods: Data were retrospectively collected from a single-center cohort of 17 consecutive patients (9 boys, 8 girls) receiving surgical deformity correction for congenital cervical scoliosis. The mean age at surgery was 7.1±3.4 years with an average follow-up of 3.6±1.1 years., Results: There were 24 operations performed on 17 patients, and 4 complications (17%) were reported in the series, including one each of pressure ulcer, asystole, vertebral artery injury, and pseudarthrosis. The mean preoperative major curve angle was 36±20 degrees, which improved to 24±14 degrees (P=0.02). The mean operative time was 8±2 hours with a mean estimated blood loss of 298±690 mL. Halo-gravity traction was used in 5 patients and 6 cases were staged with anterior/posterior procedures., Conclusions: Congenital scoliosis of the cervical spine is a complex process. The spinal deformity of this nature can be managed successfully with carefully planned and executed surgical correction., Level of Evidence: Level IV-retrospective review., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2020 Wolters Kluwer Health, Inc. All rights reserved.)