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Longitudinal observational comparative cohorts.The objective of this study is to compare 3 and 12-month radiographic sagittal parameters and patient-reported outcomes (PROs) in patients who underwent 3-level ACDF or a hybrid procedure.Anterior Cervical Discectomy and Fusion (ACDF), Anterior Cervical Corpectomy and Fusion (ACCF), and hybrids (combination ACCF-ACDF) are common procedures used to treat symptomatic cervical spondylosis. Although there is a relative abundance of literature comparing 1-level ACCF versus 2-level ACDF and 2-level ACCF versus 3-level ACDF, detailed comparisons of 3-level ACDF versus hybrid procedures have not been extensively addressed.Patients who underwent a 3-Level ACDF (3L-ACDF, N=47) or 1-Level Corpectomy/1-Level ACDF (Hybrid, N=52) with at least a 12-month post-op data available were identified. Standard demographic, surgical and PROs were collected in addition to preoperative and postoperative radiographic data, including C2 plumb line (C2PL), C2-C7 lordosis (CL), segmental lordosis (SL), and T1 slope (T1S).The 2 cohorts were similar in terms of demographics. At 3 months post-op, CL (9.04° vs. -2.12°, P=0.00) and SL (6.06° vs. -2.26°, P=0.003) were significantly greater in the 3L-ACDF group versus the HYBRID group. This significant difference was maintained at 12 months postoperative for CL [(6.62° vs. -0.60°, P=0.015) but not for SL (2.36° vs. -1.09°, P=0.199)]. There were no differences in PROs between the 2 groups before surgery, at 3 months postoperative or 12 months postoperative. Seven patients required revision surgery in the 1-year study period (1 in the 3L-ACDF, and 6 in the Hybrid P0.001).Three level ACDF resulted in greater C2-C7 lordosis and segmental lordosis postoperatively, which was maintained at 1 year for cervical lordosis. While PROs were similar between the groups, patients with hybrid instrumentation required significantly more revision surgeries than those treated with 3-level ACDF.

Computed tomography (CT) measurement of Hounsfield Units (HU) has been described as a tool for assessing BMD. For surgeons considering a revision lumbar fusion, knowledge of the BMD of the UIV is of value for surgical planning. However, the presence of metal artifact from instrumentation presents a potential confounder, and prior studies have not validated measurements of HU in this setting.To determine if HU can be measured reliably at the supra-adjacent and upper instrumented levels of a lumbar fusion.Retrospective observational cohort PATIENT SAMPLE: Consecutive series of patients who had lumbar CT scans after an instrumented posterior lumbar fusion.Hounsfield Units at the upper instrumented vertebra and levels proximal.We analysed pre- and postoperative CT scans of 50 patients who underwent L2 and distal instrumented lumbar fusion whose scans were no greater than 1 year apart, obtaining HU measurements of analogous axial cuts at the upper instrumented level (immediately caudal to the halo of the pedicle screw), as well as additional control levels above the construct.The HU at the pre-and postoperative UIV exhibited a strong correlation (r=0.917, p.001), as did one (r=0.887, p.001) and two (r=0.853, p.001) levels above the UIV. There were significant but predictable reductions in the postoperative HU compared to preoperative at one (-9.0±26.2) and two (-12.2±30.2) levels above the UIV, as well as T12 (-13.9±42.2). There was no significant difference in HU at the UIV (4.6±34.1).Postoperative HU at the UIV was strongly correlated with and not significantly different from the preoperative HU. Although the HU in the vertebrae proximal to the UIV were slightly lower postoperatively, this change was predictable using a correction factor.

BACKGROUND CONTEXT Excessive use of postoperative imaging after lumbar surgery has been documented, becoming a target for cutting costs. This must be balanced with the patient's need for information and allay their postoperative concerns. PURPOSE To determine the incidence and associated costs of patient interactions with the healthcare system, outside the standard follow up routine, in the first postoperative year. STUDY DESIGN Retrospective longitudinal cohort. PATIENT SAMPLE Consecutive series of 200 patients who underwent lumbar fusions from 2018 to 2019 from a multi-surgeon single tertiary spine center. OUTCOME MEASURES All healthcare encounters: phone calls, office and emergency department visits, and additional testing METHODS A consecutive series of 200 patients who underwent lumbar fusions from 2018 to 2019 were identified. All non-routine healthcare encounters: phone calls, office and emergency department visits, and additional testing were collected. Direct costs for all healthcare services were determined using the Medicare Allowable rates. Indirect costs were determined using local, median income, length of office visits, and distance from the clinic to the patient's home. RESULTS Of 200 patients, 14 with thoracic fusion were excluded. The mean age of the 186 included patients was 58.26 years and 85 (46%) were male. Forty-seven percent (87/186) had only routine postoperative visits and 24 had revision surgery. Seventy-five patients made a total of 102 phone calls, 55 office visits, leading to 38 diagnostic studies none of which led to an additional intervention. Using Medicare Allowable rates, the mean direct cost was $776 per patient and the using a median income of $16/h the mean indirect cost was $124 per patient. There were no differences in the baseline characteristics among the patients who only had routine post-op encounters, had non-routine encounters or had a repeat surgery. CONCLUSIONS Forty percent of the patients undergoing lumbar surgery had a healthcare encounter outside their routine follow up that did not result in additional intervention after their index operation. These potentially unnecessary encounters create additional cost and inconvenience to both the patient and healthcare system. Providing patient reassurance is important and providers should identify ways to reduce associated costs through patient education, virtual visits, or new technologies to monitor patient's postoperative progress.

STUDY DESIGN Retrospective single center propensity-matched observational cohort study that included patients who underwent 1- to 3-level lumbar fusion surgery for degenerative conditions. OBJECTIVE To compare 90-day complication rates between robotic-assisted and non-robotic-assisted lumbar spinal fusions in propensity-matched cohorts. SUMMARY OF BACKGROUND DATA A recent administrative database (PearlDiver) study reported increased 30-day complications with the utilization of robotic-assisted enabling technology. METHODS Of 146 robotic-assisted cases that met inclusion criteria, 114 were successfully propensity matched to 114 patients from 214 cases who had 1 to 3 level lumbar fusion without robotic assistance based on age, sex, body mass index, smoking status, American Society of Anesthesiologist grade, number of surgical levels, primary versus revision, and surgical approach (posterior-only or anterior-posterior). We excluded tumor, trauma, infection, or deformity cases. Outcomes included surgical and medical (major/minor) complications at intraoperative, immediately postoperative, 30- and 90-day postoperative intervals, including reoperations, and readmissions within 90 days. RESULTS All cause intraoperative complication rates were similar between non-robotic-assisted (5.3%) and robotic-assisted groups (10.5%, P = 0.366). Immediate postoperative medical complication rate was also similar between non-robotic-assisted (6.1%) and robotic-assisted groups (1.8%, P = 0.089). Thirty-day complication rates, 90-day complication rates, reoperation rates, and readmission rates showed no difference between non-robotic-assisted and robotic-assisted groups. There was no difference between return to OR for infection between the cohorts (non-robotic-assisted: 6 [5%] vs. robotic-assisted: 1 [0.8%], P = 0.119). There was however improved length of stay (LOS) in the robotic-assisted group compared with non-robotic-assisted group (2.5 vs. 3.17 days, P = 0.018). CONCLUSION In propensity-matched cohorts, patients undergoing 1- to 3-level robotic-assisted posterior lumbar fusion for degenerative conditions did not have increased 90-day complication rate, and had a shorter length of stay compared with non-robotic-assisted patients. There findings differ from a prior administrative database study as the robotic-assisted group in the current study had 0% return to OR for malpositioned screws and 0.8% return to OR for infection.Level of Evidence: 2.

Study Design.This was a dual-center study over an eight-year period on patients undergoing single level fusion surgery with either posterior- (PLIF) or transforaminal lumbar interbody fusion (TLIF). We analyzed prospectively collected pre- and postoperative data from the national Danish surgical spine database (DaneSpine).Objective.The aim of this study was to compare clinical and patient-reported outcome (PRO) 2 years after TLIF or PLIF in patients with symptomatic lumbar mechanical disc degeneration.Summary of Background Data.PLIF and TLIF are well-described techniques for treating lumbar mechanical disc degeneration but whether the theoretical differences between the two techniques translate to different clinical outcomes is unknown.Methods.The primary outcome was Oswestry Disability Index (ODI) score at 2-year follow-up. Secondary outcome measures were scores on the European Quality of Life-5 Dimensions (EQ-5D) and visual analog scale (VAS) and the rate of intraoperative complications. To minimize baseline differences between the groups, propensity-score matching was employed in a 1:1 fashion, balancing the groups on preoperative factors including age, sex, back and leg pain, ODI, EQ-5D, and previous spine surgery.Result.The matched cohort included 211 patients in each cohort. There was no significant difference between the groups in the mean score on the ODI at two years (PLIF: 33 ± 20 vs. TLIF: 35 ± 20, P = 0.328). We found no statistically significant differences in EQ-5D score (0.54 ± 0.35 vs. 0.51 ± 0.34, P = 0.327), VAS score for back pain (47 ± 32 vs. 48 ± 29, P = 0.570) or leg pain (42 ± 33 vs. 41 ± 32, P = 0.936) between the PLIF and TLIF groups, respectively, at 2-year follow-up. Dural tears occurred in 9.5% in the PLIF group and 1.9% in the TLIF group (P = 0.002) corresponding to a relative risk of 5.0 (95% CI 1.7-14.4).Conclusion.We found no significant difference in PRO at 2-year follow-up between PLIF and TLIF for the treatment of lumbar disc degeneration. PLIF is associated with a five times higher risk of dural tears.Level of Evidence: 3.

Adult spinal deformity; Patient reported outcomes; Spinal deformity surgery Deformidad espinal en el adulto; Resultados informados por el paciente; Cirugía de deformidad espinal Deformitat espinal de l'adult; Resultats informats pel pacient; Cirurgia de deformitat espinal Study Design: Prospective cohort. Objective: To prospectively evaluate PROs up to 5-years after complex ASD surgery. Methods: The Scoli-RISK-1 study enrolled 272 ASD patients undergoing surgery from 15 centers. Inclusion criteria was Cobb angle of >80°, corrective osteotomy for congenital or revision deformity, and/or 3-column osteotomy. The following PROs were measured prospectively at intervals up to 5-years postoperative: ODI, SF36-PCS/MCS, SRS-22, NRS back/leg. Among patients with 5-year follow-up, comparisons were made from both baseline and 2-years postoperative to 5-years postoperative. PROs were analyzed using mixed models for repeated measures. Results: Seventy-seven patients (28.3%) had 5-year follow-up data. Comparing baseline to 5-year data among these 77 patients, significant improvement was seen in all PROs: ODI (45.2 vs. 29.3, P < 0.001), SF36-PCS (31.5 vs. 38.8, P < 0.001), SF36-MCS (44.9 vs. 49.1, P = 0.009), SRS-22-total (2.78 vs. 3.61, P < 0.001), NRS-back pain (5.70 vs. 2.95, P < 0.001) and NRS leg pain (3.64 vs. 2.62, P = 0.017). In the 2 to 5-year follow-up period, no significant changes were seen in any PROs. The percentage of patients achieving MCID from baseline to 5-years were: ODI (62.0%) and the SRS-22r domains of function (70.4%), pain (63.0%), mental health (37.5%), self-image (60.3%), and total (60.3%). Surprisingly, mean values (P > 0.05) and proportion achieving MCID did not differ significantly in patients with major surgery-related complications compared to those without. Conclusions: After complex ASD surgery, significant improvement in PROs were seen at 5-years postoperative in ODI, SF36-PCS/MCS, SRS-22r, and NRS-back/leg pain. No significant changes in PROs occurred during the 2 to 5-year postoperative period. Those with major surgery-related complications had similar PROs and proportion of patients achieving MCID as those without these complications. The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was funded by AO Spine through the AO Spine Knowledge Forum Deformity, the Scoliosis Research Society (SRS), and Norton Healthcare. AO Spine Knowledge Forum Deformity is a focused group of international deformity experts. AO Spine is a clinical division of the AO Foundation, which is an independent medically-guided not-for-profit organization. Study support was provided directly through the AO Spine Research Department and the AO Innovation Translation Center, Clinical Evidence.

Study design Cross-sectional retrospective observational study. Objective To evaluate the reliability and clinical utility of the Modic changes (MC) grading score. Method Patients from the Danish national spine registry, DaneSpine, scheduled for lumbar discectomy were identified. MRI of patients with MC were graded based on vertical height involvement: Grade A (50%). All MRIs were reviewed by 2 physicians to evaluate the reliability of the MC grade. Results Of 213 patients included, 142 patients had MC, 71 with MC-1 and 71 with MC-2; 34% were Grade A, 45% were Grade B, and 21% were Grade C. MC grade demonstrated substantial intra-rater (κ = .68) and inter-rater (κ = .61) reliability. A significantly higher proportion (n = 40, 57%) of patients with MC-1 had a severe MC grade compared to patients with MC-2 (n = 30, 43%, P < .001). Severe MC grade was associated with the presence of severe lumbar disc degeneration (DD) (Pfirrmann grade = V, P = .024), worse preoperative ODI (52.49 vs 44.17, P = .021) and EQ-5D scores (.26 vs .46, P = .053). MC alone including type was not associated with a significant difference in patient-reported outcomes ( P > .05). Conclusion The MC grade score was demonstrated to have substantial intra- and inter-observer reliability. Severe MC grade was associated with both severe DD and MC type, being more prevalent in patients with MC-1. The MC grade was also significantly associated with worse disability and reduced health-related quality of life. Results from the study suggest that MC grade is more clinically important than MC type.

BACKGROUND: Novel methods of bone density assessment using computed tomography (CT) and magnetic resonance imaging (MRI) have been increasingly reported in the spine surgery literature. Correlations between these newer measurements and traditional Dual-Energy X-ray Absorptiometry (DEXA) is not well known. The purpose of this study is to perform an updated systematic review of correlations between bone mineral density (BMD) from CT or MRI and DEXA. METHODS: Articles published between 2011 and 2021 that reported correlations between the CT-HU or MRI measurements to DEXA t-scores or BMD of lumbar spine or hip were included in this systematic review. RESULTS: A total of 25 studies (15 CT, 10 MRI) met the inclusion criteria with a total number of 2,745 patients. The pooled correlation coefficient of spine CT-HU versus spine DEXA, spine CT-HU versus hip DEXA and spine CT-HU versus lowest t-score were 0.60, 0.50 and 0.60 respectively. Regarding spine DEXA parameters, the pooled r(2) for spine CT-HU versus spine t-score was 0.684 and spine CT-HU versus spine BMD was 0.598. Furthermore, in patients undergoing spine surgery in four studies, the pooled correlation between spine CT and spine DEXA was (r(2): 0.64). In MRI studies, the pooled r(2) of spine MRI versus spine DEXA and spine MRI versus hip DEXA were -0.41 and -0.44 respectively. CONCLUSIONS: CT-HU has stronger correlations with DEXA than MRI measurements. Lumbar CT-HU has the highest pooled correlation (r(2) = 0.6) with both spine DEXA and lowest skeletal t-score followed by lumbar CT-HU with hip DEXA (r(2) = 0.5) and lumbar MRI with hip (r(2) = 0.44) and spine (r(2) = 0.41) DEXA. Both imaging modalities achieved only a moderate correlation with DEXA. Few studies in both modalities have investigated the correlation in spine surgery populations and the available data shows that the correlations are worse in the degenerative spine population. A careful interruption of CT HU and MRI measurement when evaluation of BMD as they only moderately correlated with DEXA scores. At this time, it is unclear which modality is a better predictor of mechanical complications and clinical outcomes in spine surgery patients.

Study Design: Retrospective observational cohort. Objectives: We sought to evaluate the impact of ESR on in-hospital and 90-day postoperative opioid consumption, length of stay, urinary catheter removal and postoperative ambulation after lumbar fusion for degenerative conditions. Methods: We evaluated patients undergoing lumbar fusion surgery at a single, multi-surgeon center in the transition period prior to (N = 174) and after (N = 116) adoption of ESR, comparing in-hospital and 90-day postoperative opioid consumption. Regression analysis was used to control for confounders. Secondary analysis was preformed to evaluate the association between ESR and length of stay, urinary catheter removal and ambulation after surgery. Results: Mean age study participants was 52.6 years with 62 (47%) females. Demographic characteristics were similar between the Pre-ESR and ESR groups. ESR patients had better 3-month pain scores, ambulated earlier, had urinary catheters removed earlier and decreased in-hospital opioid consumption compared to Pre-ESR patients. There was no difference in 90-day opioid consumption between the 2 groups. Regression analysis showed that ESR was strongly associated with in-hospital opioid consumption, accounting for 30% of the variability in Morphine Milligram Equivalents (MME). In-hospital opioid consumption was also associated with preoperative pain scores, number of surgical levels, and insurance type (private vs government). Pre-op pain sores were associated with 90-day opioid consumption. Secondary analysis showed that ESR was associated with a shorter length of stay and earlier ambulation. Conclusions: This study showed ESR has the potential to improve recovery after lumbar fusion for degenerative conditions with reduced in-hospital opioid consumption and improved postoperative pain scores.

Controversy exists regarding the ability of posterior (transforaminal) lumbar interbody fusion (PLIF/TLIF) to achieve lordosis. We hypothesized that an interbody device (IBD) designed for positioning in the anterior disc space produces greater lordosis than IBDs designed for straight-in positioning. The purpose of this study is to determine if using either an anterior-position or straight-in position IBD design were associated with successful achievement of postoperative lordosis.A consecutive series of patients undergoing a undergoing a single-level, posterior open midline (transforaminal) lumbar interbody fusion procedure for degenerative spine conditions during a time period when the two types of interbody devices were being used at surgeon discretion were identified from a multi-surgeon academic training center. Patient demographics and radiographic measures including surgical level lordosis (SLL), anterior disc height, middle disc height, posterior disc height, IBD height, and IBD insertion depth were measured on preop, immediate postop, and one-year postop standing radiographs using PACS. Group comparison and regression analysis were performed using SPSS.Sixty-one patients were included (n=37 anterior, n=34 straight-in). Mean age was 59.8±8.7 years, 32 (52%) were female. There was no difference between IBD type (anterior vs. straight-in) for mean Pre-op SLL (19±7° vs. 20±6°, p=0.7), Post-op SLL (21±5° vs 21±6°, p=0.5), or Change in SLL (2±4° vs. 1±5°, p=0.2). Regression analysis showed that Pre-op SLL was the only variable associated with Change in SLL (Beta = negative 0.48, p=0.000). While the mean Change in SLL could be considered clinically insignificant, there was wide variability: from a loss of 9° to a gain of 13°. Gain of lordosis5° only occurred when Pre-op SLL was21°, and loss of lordosis5° only occurred when Pre-op SLL was21°.While group averages showed an insignificant change in segmental lordosis following a posterior (transforaminal) interbody fusion regardless of interbody device type, pre-operative lordosis was correlated with a clinically significant change in segmental lordosis. Preoperative hypolordotic discs were more likely to gain significant lordosis, while preoperative hyperlordotic discs were more likely to lose significant lordosis. Surgeon awareness of this tendency can help guide surgical planning and technique.

Study Design: Retrospective/prospective study. Objective: Models based on preoperative factors can predict patients’ outcome at 1-year follow-up. This study measures the performance of several machine learning (ML) models and compares the results with conventional methods. Methods: Inclusion criteria were patients who had lumbar disc herniation (LDH) surgery, identified in the Danish national registry for spine surgery. Initial training of models included 16 independent variables, including demographics and presurgical patient-reported measures. Patients were grouped by reaching minimal clinically important difference or not for EuroQol, Oswestry Disability Index, Visual Analog Scale (VAS) Leg, and VAS Back and by their ability to return to work at 1 year follow-up. Data were randomly split into training, validation, and test sets by 50%/35%/15%. Deep learning, decision trees, random forest, boosted trees, and support vector machines model were trained, and for comparison, multivariate adaptive regression splines (MARS) and logistic regression models were used. Model fit was evaluated by inspecting area under the curve curves and performance during validation. Results: Seven models were arrived at. Classification errors were within ±1% to 4% SD across validation folds. ML did not yield superior performance compared with conventional models. MARS and deep learning performed consistently well. Discrepancy was greatest among VAS Leg models. Conclusions: Five predictive ML and 2 conventional models were developed, predicting improvement for LDH patients at the 1-year follow-up. We demonstrate that it is possible to build an ensemble of models with little effort as a starting point for further model optimization and selection.

Study Design Randomized controlled trial with minimum of 5-years follow-up. Objective The purpose of this study is to evaluate the peri- and postoperative complications rates, ectopic bone migration, and reoperation rates, and secondly evaluate the 5-year patient reported outcomes (PROs), in patients treated with decompression and non-instrumented posterolateral fusion with ABM/P-15 or allograft. Methods Patients with degenerative spondylolisthesis were enrolled in a Randomized Clinical Trial and randomized 1:1 to either ABM/P-15 or allograft bone. Patient Reported Outcomes were collected at 5-year follow-up, and patients were invited to a clinical follow-up including a computed tomography scan (CT) to evaluate signs of osteolysis, ectopic bone formation, and bone migration. Results Of 101 subjects enrolled in the primary study, 83 patients were available for the 5-year follow-up. We found a statistically significant difference in back pain and Oswestry Disability Index between groups. Fifty-eight patients agreed to participate in the CT study. Sixty percentage in the ABM/P-15 group vs 30% in the allograft group was classified as fused ( P = .037). There were no differences in complications, reoperation-, or infection rates between the 2 groups. We found 2 patients with migration of graft material. Both patients were asymptomatic at minimum 5-year follow-up. Conclusion Our study indicated that complication rates are no higher in patients treated with ABM/P-15 than allograft. We found significantly higher fusion rates in the AMB/P-15 group than in the allograft group, and patients in the ABM/P-15 group reported less back pain and lower disability score at 5-year follow-up.

STUDY DESIGN Prospective longitudinal cohort. OBJECTIVES The aim of this study was to determine whether functional treadmill testing (FTT) demonstrates differences between patients treated operatively and nonoperatively for adult symptomatic lumbar scoliosis (ASLS). SUMMARY OF BACKGROUND DATA ASLS has become increasingly prevalent as the population ages. ASLS can be accompanied by neurogenic claudication, leading to difficulty walking. FTT may provide a functional tool to evaluate patients with ASLS. METHODS One hundred and eighty-seven patients who underwent nonoperative (n = 88) or operative treatment (n = 99) of ASLS with complete baseline and 2-year post-treatment FTTs and concurrent patient-reported outcomes were identified. FTT parameters included maximum speed, time to onset of symptoms, distance ambulated, time ambulated, and Back and Leg pain severity before and after testing. RESULTS At baseline, patients treated operatively reported worse post-FTT back pain (4.39 vs. 3.45, P = 0.032) than those treated nonoperatively, despite similar ODI, SRS-22 Pain and Activity domain scores. Mean time ambulated (+2.15 vs. -1.20 P = 0.001), pre-FTT back pain (+0.19 vs. -1.60, P

STUDY DESIGN: A registry-based comparative cohort study with 2-year follow-up.OBJECTIVE: To assess whether Modic changes (MCs) are associated with health-related quality of life, long-term physical disability, back- or leg pain after discectomy.SUMMARY OF BACKGROUND DATA: Previous studies have failed to show a clinically significant association between MCs and patient-reported outcomes (PROs) after discectomy.METHODS: Data from the Danish National Spine Registry on patients undergoing first-time lumbar discectomy at a single institution from 2014 to 2017 with an accessible preoperative lumbar magnetic resonance imaging, complete preoperative, and 2-year follow-up questionnaires were obtained. PROs including Oswestry disability index (ODI), European Quality of Life-Five Dimensions (EQ-5D), visual analogue scale (VAS) back and leg pain, and patient satisfaction were collected. Patients were stratified based on the presence (+MC) or absence (-MC) of MCs on the preoperative MRI.RESULTS: Of 620 patients included, MCs were present in 290 patients (47%). Of these, MC type 1 (MC-1) was present in 73 (25%) and MC type 2 (MC-2) in 217 (75%) patients. Preoperative data for ODI, EQ-5D, VAS-BP, and VAS-LP were comparable for the +MC and -MC groups. Both groups had a statistically significant improvement in PROs from baseline compared with 2-year follow-up (P CONCLUSION: MCs were not found to be associated with health-related quality of life, disability, back- or leg pain, or patient satisfaction 2 years after discectomy.LEVEL OF EVIDENCE: 2.

Study Design: Longitudinal cohort. Objectives: Posterior spinal fusion (PSF) using all-pedicle screw constructs has become the standard procedure in the treatment of adolescent idiopathic scoliosis (AIS). However, there have been several reports that all-pedicle screw constructs or the use of pedicle screws at the upper instrumented vertebrae (UIV) increases the incidence of proximal junctional kyphosis (PJK). We aimed to evaluate the impact of instrumentation type on the incidence of PJK following PSF for AIS. Methods: We performed a stratified random sampling from 3654 patients enrolled in a multicenter database of surgically treated AIS to obtain a representative sample from all Lenke types. Patients were then allocated into 3 groups based on the instrumentation type: all-pedicle screw (PS), hook at UIV with pedicle screws distally (HT), and hybrid constructs (HB). We measured proximal junctional angle (PJA) and defined PJK as PJA ≥ 10° and PJA progression of >10° at the final follow-up. Results: Fifteen (4.3%) of 345 cases had PJK. PJK was significantly more common in PS (11%) compared with HB (1%) and HT (0%) ( P < .001). PJK patients were similar to non-PJK patients regarding age, sex, curve type, UIV, and preoperative coronal Cobb angle. Thoracic kyphosis was significantly higher in the PJK group before surgery. Patients who developed PJK had a statistically significantly larger negative sagittal balance compared with the non-PJK group. Conclusion: The incidence of PJK was 4.3% and was more common in all-pedicle screw constructs. Using hooks at UIV might be a treatment strategy to limit PJK.

Study design A retrospective review of prospectively collected data. Objective The objective of this study was to investigate the fusion status of the lumbar spine and lumbosacral junction at 2 years postoperatively after complex adult spinal deformity (ASD) surgery. Summary of background data Achieving fusion is crucial for maintaining optimal alignment in ASD surgery. However, prospective data assessing fusion status using large patient populations are lacking in this patient population. Materials and methods Postoperative radiographs of 162 patients from the Scoli-Risk-1 database, who underwent complex ASD surgery with fusion to the sacrum, were evaluated by 3 independent spine surgeons at 6-week, 6-month, and 2-year follow-up. The fusion rate of the lumbar spine segments at a 2-year follow-up was determined by using previously published radiographic grading criteria. We also assessed the prevalence of instrumentation failures. Results The interrater reliabilities for grading the fusion status were overall fair at each level evaluated (Fleiss κ, 0.337-0.439). Overall, 70.3% (114/162) demonstrated the solid fusion of the entire lumbar spine at a 2-year follow-up. The fusion rates of each segment were L1/L2: 87.0%, L2/L3: 82.0%, L3/L4: 83.9%, L4/L5: 89.5%, and L5/S1: 89.5%. Pedicle screw loosening was the most frequent implant failure throughout the observation period (9.2%, 11.6%, and 11.0% at 6-wk, 6-mo, and 2-y follow-up, respectively). No rod breakage was observed at 6 weeks, increasing to 9.8% at 2-year follow-up. The prevalence of postoperative proximal junctional kyphosis was 5.5% at 6 weeks, showing no difference at 2 years postoperative. Conclusions In this series of complex ASD surgeries often requiring 3-column osteotomies, 70.3% showed solid fusion of the entire lumbar spine, including the lumbosacral junction. The lumbosacral segments showed a relatively high fusion rate at a 2-year follow-up likely due to the frequent use of anterior column support and graft. The prevalence of rod breakage increased as follow-up proceeded to 9.8%, which was most commonly observed at the lumbosacral junction. Level of evidence Level IV.

Study Design: Longitudinal cohort study with 13-year follow-up. Objective: To assess whether long-term disability is associated with baseline degenerative magnetic resonance imaging (MRI) findings in patients with low back pain (LBP). Methods: In 2004-2005, patients aged 18 to 60 years with chronic LBP were enrolled in a randomized controlled trial and lumbar MRI was performed. Patients completed the Roland-Morris Disability Questionnaire (RMDQ) and the LBP Rating Scale, at baseline and 13 years after the MRI. Multivariate regression analysis was performed with 13-year RMDQ as the dependent variable and baseline disc degeneration (DD, Pfirrmann grade), Modic changes (MC), facet joint degeneration (FJD, Fujiwara grade) smoking status, body mass index, and self-reported weekly physical activity at leisure as independent variables. Results: Of 204 patients with baseline MRI, 170 (83%) were available for follow-up. Of these, 88 had Pfirrmann grade >III (52%), 67 had MC (39%) and 139 had Fujiwara grade >2 (82%) on at least 1 lumbar level. Only MC (β = −0.15, P = .031) and weekly physical activity at leisure (β = −0.51, P < .001) were significantly, negatively, associated with 13-year RMDQ-score ( R2 = 0.31). Conclusion: DD and FJD were not associated with long-term disability. Baseline MC and weekly physical activity at leisure were statistically significantly associated with less long-term disability.

Economic modeling of data from a multicenter, prospective registry.The aim of this study was to analyze the cost utility of recombinant human bone morphogenetic protein-2 (BMP) in adult spinal deformity (ASD) surgery.ASD surgery is expensive and presents risk of major complications. BMP is frequently used off-label to reduce the risk of pseudarthrosis.Of 522 ASD patients with fusion of five or more spinal levels, 367 (70%) had at least 2-year follow-up. Total direct cost was calculated by adding direct costs of the index surgery and any subsequent reoperations or readmissions. Cumulative quality-adjusted life years (QALYs) gained were calculated from the change in preoperative to final follow-up SF-6D health utility score. A decision-analysis model comparing BMP versus no-BMP was developed with pseudarthrosis as the primary outcome. Costs and benefits were discounted at 3%. Probabilistic sensitivity analysis was performed using mixed first-order and second-order Monte Carlo simulations. One-way sensitivity analyses were performed by varying cost, probability, and QALY estimates (Alpha = 0.05).BMP was used in the index surgery for 267 patients (73%). The mean (±standard deviation) direct cost of BMP for the index surgery was $14,000 ± $6400. Forty patients (11%) underwent revision surgery for symptomatic pseudarthrosis (BMP group, 8.6%; no-BMP group, 17%; P = 0.022). The mean 2-year direct cost was significantly higher for patients with pseudarthrosis ($138,000 ± $17,000) than for patients without pseudarthrosis ($61,000 ± $25,000) (P 0.001). Simulation analysis revealed that BMP was associated with positive incremental utility in 67% of patients and considered favorable at a willingness-to-pay threshold of $150,000/QALY in52% of patients.BMP use was associated with reduction in revisions for symptomatic pseudarthrosis in ASD surgery. Cost-utility analysis suggests that BMP use may be favored in ASD surgery; however, this determination requires further research.2.

Study design Secondary analysis of subjects in the control anterior cervical discectomy and fusion (ACDF) arm of Medtronic Investigational Device Exemption (IDE) trials for cervical disc arthroplasty (CDA). Objectives To compare patient-reported outcomes (PROs) in patients with radiographic nonunion to patients with a solid fusion. Summary of background data The true prevalence of nonunion after ACDF is unknown. Nonunion may be under-reported, as some patients are not symptomatic enough to justify radiographic evaluation. Methods Three hundred forty-five subjects enrolled in the control arm of IDE trials for CDA who had single-level ACDF with allograft and plate with 24 month data formed the study cohort. Using the 24-month postop evaluation, subjects were divided into those who had radiographic fusion and those who did not using strict study criteria. SF-36, NDI, Neck and Arm pain NRS scores were reported at 12, 24, 36, 60, and 84 months postop. For subjects who had secondary surgery failures, the last observations before the secondary surgery were carried forward to future visits for the analysis. Results Forty-four (13%) patients had radiographic nonunion and 301 (87%) were fused at 24 months postop. At 24 months, PROs were similar between the two groups. Seven patients in the Nonunion group (16%) and 10 (3%) in the Fused group had additional surgery at the index level prior to the 24 follow-up (P = 0.003). Over the 84-month follow-up a total of 9 patients in the Nonunion group (21%) and 22 (7%) in the Fused group had additional surgery at the index level (P = 0.009). Conclusion While the radiographic nonunion rate at 24 months was 13%, PROs show that many of the radiographic nonunions were asymptomatic. Although the majority of patients with radiographic nonunion did not undergo additional surgery, the rate of secondary surgeries at the index level was significantly higher in the radiographic nonunion group. Level of evidence 2.

BACKGROUND CONTEXT: Patients undergoing lumbar discectomy are typically referred for postoperative rehabilitation. However, evidence regarding effectiveness of postoperative rehabilitation to improve surgical outcome and hasten return to work is scarce with conflicting results in the published literature.PURPOSE: This study investigates the effect of postoperative rehabilitation on return to work, duration of sick leave and working ability after surgery for lumbar disc herniation.STUDY DESIGN/SETTING: Single center randomized controlled trial.PATIENT SAMPLE: Patients scheduled for primary discectomy due to lumbar disc herniation were included in the study.OUTCOME MEASURES: Self-reported measures included working ability, work status and job type defined by the International Standard Classification of Occupations. All outcomes including duration of sick leave were obtained from follow-up questionnaires at one and two years after surgery.METHODS: This is a secondary analysis from a randomized controlled trial comparing patients who were referred to rehabilitation at the municipal facility starting 4-6 weeks postoperative (REHAB) and patients sent home after surgery without any planned rehabilitation course (HOME). Linear regression was performed to identify baseline characteristics associated with duration of sick leave.RESULTS: One hundred forty-six patients were included and equally distributed between the groups. Follow-up rate was 78% after one and two years. Both groups had a similar postoperative sick leave period of approximately 9 weeks. After one year 79% had returned to work in the HOME-group versus 74% in the REHAB-group, which was not statistically significant. Working ability improved from baseline to one year in both groups and this improvement was sustained at two-year follow-up. Stepwise linear regression showed that preoperative duration of leg pain and working ability were associated with duration of postoperative sick leave.CONCLUSIONS: Referral for unstandardized municipal rehabilitation does not affect duration of postoperative sick leave, return to work or working ability in patients recovering after surgery for lumbar disc herniation. Duration of preoperative leg pain and preoperative working ability was significantly associated with the duration of postoperative sick leave.

STUDY DESIGN Post-hoc analysis of a prospective, multicenter cohort study. OBJECTIVE To analyze the impact of smoking on rates of postoperative adverse events (AEs) in patients undergoing high-risk adult spine deformity surgery. SUMMARY OF BACKGROUND DATA Smoking is a known predictor of medical complications after adult deformity surgery, but the effect on complications, implant failure and other AEs has not been adequately described in prospective studies. METHODS Twenty-six patients with a history of current smoking were identified out of the 272 patients enrolled in the SCOLI-RISK-1 study who underwent complex adult spinal deformity surgery at 15 centers, with 2-year follow-up. The outcomes and incidence of AEs in these patients were compared to the nonsmoking cohort (n = 244) using univariate analysis, with additional multivariate regression to adjust for the effect of patient demographics, complexity of surgery, and other confounders. RESULTS The number of levels and complexity of surgery in both cohorts were comparable. In the univariate analysis, the rates of implant failure were almost double (odds ratio 2.28 [0.75-6.18]) in smoking group (n = 7; 26.9%)) that observed in the nonsmoking group (n = 34; 13.9%), but this was not statistically significant (P = 0.088). Surgery-related excessive bleeding (>4 L) was significantly higher in the smoking group (n = 5 vs. n = 9; 19.2% vs. 3.7%; OR 6.22[1.48 - 22.75]; P = 0.006). Wound infection rates and respiratory complications were similar in both groups. In the multivariate analysis, the smoking group demonstrated a higher incidence of any surgery-related AEs over 2 years (n = 13 vs. n = 95; 50.0% vs. 38.9%; OR 2.12 [0.88-5.09]) (P = 0.094). CONCLUSION In this secondary analysis of patients from the SCOLI-RISK-1 study, a history of smoking significantly increased the risk of excessive intraoperative bleeding and nonsignificantly increased the rate of implant failure or surgery-related AEs over 2 years. The authors therefore advocate a smoking cessation program in patients undergoing complex adult spine deformity surgery. LEVEL OF EVIDENCE 2.

Study Design: Validation study. Objectives: To translate and validate the Zurich Claudication Questionnaire (ZCQ) into a Danish version of the disease-specific patient-reported outcome measure (PROM) for patients with lumbar spinal stenosis (LSS), which assesses symptom severity, physical function, and satisfaction after surgery. Method: Translation into a Danish version of the original questionnaire by back- and forward-translating the questionnaire and finally transforming a prefinal test version into a final and cross-cultural adapted version. Validation was performed as a cohort study assessing floor-ceiling effects, internal consistency, test-retest reproducibility, criterion validity, discriminant validity, and responsiveness to change. Results: Fifty-three patients were consecutively included in the study, 53 healthy controls were matched. Floor effect was seen in the postoperative data. Internal consistency, Cronbach’s alpha was good to excellent. Substantial test-retest reproducibility was found using Cohen’s weighted kappa. The Danish ZCQ showed moderate to strong association with similar domains of Oswestry Disability Index, Short Form 36, Euro QoL 5D, visual analogue scale–leg and back. The questionnaire showed significant responsiveness to change and a significant discriminant validity between LSS patients and healthy controls. Conclusion: This study shows the Danish translation of the original ZCQ to be well understood by Danish patients. The Danish version is furthermore a reliable and valid questionnaire, which is responsive to change.

Background context Patients undergoing single-level posterior lumbar decompression and fusion (PLDF) usually do not need transfusions. However, patients undergoing two or three-level PLDF occasionally require transfusion postoperatively even when estimated blood loss (EBL) or blood loss from drains appears acceptable. Estimating the volume of HBL is critical in perioperative fluid management. Purpose To determine the volume of hidden blood loss (HBL) in 2- or 3- level PLDF. Study Design Single center, multi-surgeon, secondary analysis from a prospective randomized clinical trial of cell-saver use. Patient Sample Patients enrolled in a prospective randomized trial of cell-saver undergoing two- or three-level PLDF were included in this analysis. Methods Total blood loss was calculated using four estimation formulas including Bourke's, Gross’, Camarasa's, and Lopez-Picado's formulas. HBL was determined by subtracting the visible loss (EBL and blood loss from drains) from the calculated total blood loss. Results A total of 89 patients (36 males, mean age 62 years) were included. Seventy-five patients underwent open two-level fusion while 14 had three-level fusions. Intervertebral fusion was performed in 20 patients. Mean surgical time was 261 minutes, and EBL was 685 ml. Mean blood loss from drains was 824 ml. Seventy patients received allogenic blood while 47 Cell Saver blood reinfused intraoperatively. Hidden blood loss was calculated to be 678 ml, 963 ml, 1267 ml, and 819 ml using each formula. Conclusions HBL following two or three-level PLDF was substantial and more than EBL. Postoperative management of blood loss should take HBL into account.

STUDY DESIGN: Propensity-matched retrospective study of patients prospectively enrolled in Danespine.OBJECTIVE: The aim of this study was to report 5-year patient reported outcome in lumbar spinal stenosis (LSS) patients who underwent wide laminectomy (WL), segmental bilateral laminotomies (SBL), or unilateral hemilaminectomy (UHL) with bilateral decompression.SUMMARY OF BACKGROUND DATA: The optimal procedure for LSS remains controversial. Studies have shown no difference in short term outcomes among micro-laminectomy, hemi-laminotomies, broad laminectomy, and laminectomy with instrumented fusion.METHODS: Patients with spinal stenosis who were enrolled in DaneSpine at two spine centers from January 2010 until May 2014 and underwent WL0, SBL, or UHL with bilateral decompression were identified. Patients completed standard questionnaires preoperatively and 1, 2, and 5 years after surgery. Patients in the three cohorts were propensity-matched using age, sex, body mass index (BMI), smoking status, number of surgical levels, American Society of Anesthesiologists (ASA) score, and patient-reported outcome measures (PROMs).RESULTS: Propensity matching produced 62 cases in each group. There were no differences in PROM among the three cohorts at five years follow up. Twelve patients were re-operated at the index level. The most frequent indication of reoperation was repeat decompression after SBL. Regression analysis revealed no statistical significant associations between the incidence of reoperation and age, sex, number of operated levels, ASA score, BMI, center, smoking status, or having a dural tear at index operation.CONCLUSION: This study revealed no significant difference PROMs, reoperation rates or time to reoperation at five years follow up between SBLs, UHL, or WL in patients operated for central LSS.Level of Evidence: 4.

Study Design Prospective observational cohort. Objectives To examine the cost-effectiveness of IntraOperative ElectroMyeloGraphy (IO-EMG) by evaluating how often an abnormal IO-EMG signal changed the surgeon’s surgical plan, or replaced a pedicle screw either intra-operatively or as a second unplanned surgery. Methods Patients undergoing instrumented posterolateral lumbar fusion were monitored with intraoperative triggered EMG’s. Pedicle screws were placed freehand from L1 to S1 by attending physicians and fellows. Concern for pedicle breach was a screw stimulationResults There were 145 cases with a total of 725 pedicle screws placed. Mean age was 57.8 ± 14.2 yrs, OR time was 238 ± 95 minutes, EBL was 426.8 ± 354.3cc. Mean number of surgical levels fused was 2.7 ± 1.1. 686 (95%) screws stimulated at >10 mA and 39 (5%) screws stimulated at Conclusions Only 1% of the 725 lumbar pedicle screws placed in 8 of 145 cases required repositioning. Due to the infrequency of pedicle wall breaches and the cost of ION, the utility of this modality in straightforward lumbar fusions should be critically evaluated.

Background Context In patients with lumbar spinal stenosis, it is crucial for clinicians to identify all symptomatic levels. Prior studies have demonstrated that CT-Myelo has a greater sensitivity in revealing stenosis (94.4%) compared to MRI (75.9%). However, this is an invasive test that should be used judiciously. No study has identified subgroups of patients that do or do not benefit from this additional invasive testing. Purpose The objective of this study was to identify subgroups of patients with lumbar stenosis for whom CT myelogram could be expected to provide additional information following an MRI scan. Study Design Retrospective Chart Review Study Sample Consecutive series of patients with lumbar degenerative disease seen at a single multi-surgeon tertiary spine center. Outcome measures Degree of stenosis on MRI or CT-myelo Methods Medical records were reviewed to collect standard demographic and surgical data and patient diagnoses. MRI and CT-Myelo obtained within six months of each other in patients >45 years old with a diagnosis of central stenosis, spondylolisthesis or degenerative scoliosis were reviewed. Each lumbar level was recorded as mild, moderate, or severe based on the radiologist's report. Fisher exact test was performed with change in recorded severity of stenosis from MRI to CT-Myelo as the primary outcome of interest. Results Of 269 patients, 207 (80%) had at least one level of moderate or severe central stenosis on MRI and 62 had mild or no stenosis on MRI. Of the 207, 139 (67%) had multilevel stenosis and 68 (33%) had single level stenosis. CT-Myelo identified a greater proportion of additional stenotic levels in patients with multilevel stenosis (80/139, 58%) compared to patients with single-level stenosis (27/68, 40%, p=0.018). In 62 patients with a clinical diagnosis of lumbar stenosis but no moderate to severe stenosis on MRI, CT myelogram identified three additional stenotic levels (3/65, 5%, p=0.836). Conclusion CT Myelography is not as useful in providing additional information in patients with no stenosis or single level stenosis as compared to patients with multilevel stenosis.

Background Context There are situations that require the replacement of pedicle screws. They are often exchanged when loose or broken or to accommodate a different sized rod or pedicle screw system. Traditionally, pedicle screws are replaced by up-sizing the core diameter until an interference fit is obtained. However, this method carries a risk of pedicle screw breach. Purpose To determine if dual pitch screws, with cancellous pitch in the vertebral body and cortical pitch throughout the pedicle, allows for in-line screw revision without upsizing screw diameter. Study Design Cadaveric biomechanical Study Patient Sample Not applicable Outcome Measures Not applicable Methods Pedicle screws were tested in the lumbar vertebrae from eleven cadavers. Standard pitch 5.5 mm screws were inserted and loaded using a "break-in" protocol. Screws were removed and replaced with one of four screw types: 5.5 mm Standard Pitch, 5.5 mm Dual Pitch, 6.0 mm Standard Pitch, or 6.0 mm Dual Pitch. Failure testing was done using a stepwise increasing cyclic loading protocol for 100 cycles at each increasing load level. The loading consisted of a combined axial and bending load simulating the load seen by the most inferior screw. Results Failure was consistent, with the tip of the screw displacing inferiorly into the vertebral body while simultaneously pulling out. Failure strength was lowest in the 5.5mm Standard (135.8±29.4N) followed by 6.0mm Standard (141.8±38.6N), 5.5mm Dual (158.1±53.8N), and 6.0mm Dual (173.6±52.1N, p=.023). There was no difference in the failure strength between the 5.5mm Dual and 6.0mm Standard. Lumbar level (p=.701) and donor spine (p=.062) were not associated with failure strength. Conclusions After pedicle screw removal, screws with a larger core diameter or with a dual pitch have similar failure strengths. Dual pitch screws may allow for in-line revision of screws without upsizing screw diameter, minimizing the risk of pedicle breach or fracture. Clinical Significance Dual pitch screws, with cancellous pitch in the vertebral body and cortical pitch through the pedicle, allows for in-line revision of pedicle screws without upsizing screw diameter; reducing the risk of pedicle breach or fracture when exchanging screws.

BACKGROUND CONTEXT Surgical decision-making for cervical spondylotic myelopathy (CSM) relies on evaluation of symptoms and physical examination. The Romberg test is a clinical exam used to identify balance issues with CSM. However, the Romberg test has a subjective interpretation and has a binary (positive or negative) result. While previous studies showed that force plate pressure readings provide quantitative measurements that objectively identify poor postural control in patients with CSM, the study compared an older CSM patient cohort with a significantly younger normal cohort, failing to account for regular aging changes. PURPOSE This study aims to compare force plate pressure readings during a standard Romberg test in patients with CSM to age-matched normal healthy volunteers. STUDY DESIGN/SETTING Longitudinal observational comparative cohort from a single multisurgeon spine center. PATIENT SAMPLE Patients who were clinically diagnosed with CSM (mean age 54.8 years, N=27) were compared to age-matched healthy volunteers (mean age 54.4 years, N=27) without a clinical history of cervical pathology. OUTCOME MEASURES Quantitative Romberg Force Plate Measurements. METHODS Patients with CSM requiring surgery and healthy normal volunteers were asked to perform the Romberg test while on a force plate measuring the center of pressure (COP): standing up straight with arms extended for 30 seconds with eyes open, followed by 30 seconds with eyes closed. The change for sway area, sway frequency and sway speed with eyes closed and eyes open were calculated and compared between patients with CSM and healthy volunteers. RESULTS Twenty-seven of 48 CSM patients were age-matched to 27 healthy volunteers. There was a larger change in Romberg measurements with eyes open vs eyes closed in CSM patients compared to normal volunteers for maximum lateral movement (12.1mm2 vs 4.1mm2, p CONCLUSIONS Poor standing balance can be quantified in patients with CSM. Quantifying standing balance in patients with CSM shows significantly worse objective measures than age-matched healthy volunteers. The Romberg test on a force plate may help diagnose and evaluate patients with CSM, guide patient management, potentially grade the severity of spinal pathology, allow more timely surgical intervention, and improve surgical outcomes. Further studies are needed to determine its utility in monitoring disease progression and measure treatment effectiveness. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Study Design: A retrospective study. Objectives: Curve flexibility in patients with adolescent idiopathic scoliosis (AIS) can be evaluated using different techniques. This study aimed to determine whether the combination of side-bending (SB) and traction (TX) radiographs influences preoperative planning for AIS than either radiograph alone. Methods: Thirty-two spine surgeons were asked to review 30 AIS Lenke type 1 cases and select an upper instrumented vertebra (UIV) and lower instrumented vertebra (LIV) for the posterior spinal instrumentation of each case. Each rater reviewed the cases 3 times in each round. The raters were provided with the full-length posteroanterior (PA) and lateral standing and SB radiographs for round 1; PA, lateral, and TX radiographs for round 2; and PA, lateral, SB, and TX radiographs for round 3. Intra- and inter-rater reliabilities were evaluated using Kappa statistics. Results: The intra-rater reliability for UIV and LIV was 0.657 and 0.612 between rounds 1 and 2, 0.634 and 0.692 between rounds 1 and 3, and 0.659 and 0.638 between rounds 2 and 3, respectively, which indicated substantial agreement between rounds. The inter-rater kappa reliabilities for UIV and LIV selection were 0.103 and 0.412 for round 1, 0.121 and 0.380 for round 2, and 0.125 and 0.368 for round 3, indicating slight to moderate agreement between raters. Conclusions: Whether raters used either SB or TX radiography, or both in addition to PA and lateral standing radiographs, did not influence the decision making for UIV or LIV of AIS Lenke type 1 surgery.

STUDY DESIGN Secondary analysis of prospective multicenter cohort. OBJECTIVE To assess effect of serious adverse events (SAEs) on 2- and 4-year patient-reported outcomes measures (PROMs) in patients surgically treated for adult symptomatic lumbar scoliosis (ASLS). SUMMARY OF BACKGROUND DATA Operative treatment for ASLS can improve health-related quality of life, but has high rates of SAEs. How these SAEs effect health-related quality of life remain unclear. METHODS The ASLS study assessed operative versus nonoperative ASLS treatment, with randomized and observational arms. Patients were 40- to 80-years-old with ASLS, defined as lumbar coronal Cobb ≥30° and Oswestry Disability Index (ODI) ≥20 or Scoliosis Research Society-22 (SRS-22) ≤4.0 in pain, function, and/or self-image domains. SRS-22 subscore and ODI were compared between operative patients with and without a related SAE and nonoperative patients using an as-treated analysis combining randomized and observational cohorts. RESULTS Two hundred eighty-six patients were enrolled, and 2- and 4-year follow-up rates were 90% and 81%, respectively, although at the time of data extraction not all patients were eligible for 4-year follow-up. A total of 97 SAEs were reported among 173 operatively treated patients. The most common were implant failure/pseudarthrosis (n = 25), proximal junctional kyphosis/failure (n = 10), and minor motor deficit (n = 8). At 2 years patients with an SAE improved less than those without an SAE based on SRS-22 (0.52 vs. 0.79, P = 0.004) and ODI (-11.59 vs. -17.34, P = 0.021). These differences were maintained at 4-years for both SRS-22 (0.51 vs. 0.86, P = 0.001) and ODI (-10.73 vs. -16.69, P = 0.012). Despite this effect, patients sustaining an operative SAE had greater PROM improvement than nonoperative patients (P

STUDY DESIGN: This cohort study was an analysis of prospectively collected data in the DaneSpine Database.OBJECTIVE: The objective was to determine whether preoperative magnetic resonance imaging (MRI) findings were associated with the frequency of surgical revision due to recurrent lumbar disc herniation (LDH) within 3 years after first-time, single-level, simple lumbar discectomy.SUMMARY OF BACKGROUND DATA: Because of a risk of poorer outcome in patients receiving revision surgery compared with first-time discectomy, there is a need to identify patients with LDH in risk of surgical revision prior to the primary discectomy. The association between preoperative MRI findings and revision surgery in patients with LDH has not been thoroughly studied.METHODS: Following an interobserver reliability study preoperative MRIs were evaluated. Potential predictive variables for surgical revision were evaluated using univariate and multivariate logistic regression analysis. Also, a sum-score of the number of MRI findings at the involved level was assessed.RESULTS: In a study population of 451 operated patients, those who had surgical revision were significantly younger and were significantly less likely to have vertebral endplate signal changes Type 2 (OR 0.36 (95% CI 0.15-0.88)) or more than five MRI findings (OR 0.45 (95% CI 0.21-0.95)) at the involved level than the patients not undergoing surgical revision. Surgical revision was not significantly associated with any other MRI findings.CONCLUSIONS: In general, preoperative MRI findings have a limited explanatory value in predicting surgical revision within 3 years after first-time, single-level, simple lumbar discectomy. Both the single variable VESC Type 2 and a sum-score > 5 MRI findings at the operated level were found to be negatively associated with patients undergoing surgical revision.LEVEL OF EVIDENCE: 3.

Study Design:Longitudinal cohort.Objectives:The Hospital Anxiety and Depression Scale (HADS) was developed to provide clinicians a reliable, valid, and practical tool to identify and quantify the anxiety and depression in medical patients. Several studies have shown that patients with chronic low back pain may have subclinical depression and impairments in mental health and that these in turn may lead to less than optimal results after lumbar spine surgery. The purpose of this study is to determine if there are associations between preoperative HADS and differences in pre- and postoperative health-related quality-of-life (HRQOLs) scores after spine surgery.Methods:From a single center, a consecutive series of patients completed the HADS, Oswestry Disability Index (ODI), Short Form-36 (SF-36), EuroQOL-5D (EQ-5D), and Visual Analog Scale (VAS) for back and leg pain. Except for HADS, the patients completed the same HRQOLs 1 year after surgery.Results:Of 308 eligible cases, 208 (68%) had follow-up data available and were included in the analysis. Patients in the HADS-Anxiety (HADS-A) Abnormal category had the worst preoperative HRQOLs but had the greatest improvement in 1-year postoperative scores. Except for VAS Leg Pain, preoperative HRQOLs were better in patients in the HADS-Depressed (HADS-D) Normal category. Patients in the HADS-D Abnormal category had statistically significantly greater improvement in 1-year postoperative EQ-5D and ODI scores when compared with the other cohorts.Conclusion:Worse HADS-A and HADS-D scores are associated with worse preoperative HRQOL scores in patients with lumbar degenerative disorders scheduled for spine surgery. However, similar improvements in HRQOLs can be expected 1 year postoperative regardless of the patients’ HADS scores.

BACKGROUND CONTEXT Health literacy, defined as “the degree to which individuals have the capacity to obtain, process, and understand basic health information and services needed to make appropriate health decisions,” has been demonstrated to affect access to care and appropriate healthcare utilization. PURPOSE To determine the impact of health literacy in the evaluation and management of patients with chronic low back pain. STUDY DESIGN Cross sectional. PATIENT SAMPLE Patients seen at a multisurgeon spine specialty clinic. OUTCOME MEASURES Oswestry Disability Index, EQ-5D, and Numeric Rating Scales (0–10) for back and leg pain. METHODS The Newest Vital Sign (NVS) and Health Literacy Survey, Oswestry Disability Index, EQ-5D and pain scales were administered to patients undergoing evaluation and treatment for lumbar degenerative disease in the outpatient setting. Patients were surveyed regarding their use of medication, therapy, and pain management modalities. RESULTS Of 201 patients approached for participation, 186 completed the health literacy surveys. Thirty (17%) were assessed as having limited literacy, 52 (28%) as possibly having limited literacy and 104 (56%) having adequate literacy based on their NVS scores. The cohort with low NVS scores also had low Health Literacy Survey Scores. Patients with limited literacy had worse back and leg pain scores compared with patients with possibly limited literacy and adequate literacy. Patients with adequate health literacy were more likely to use medications (80% vs. 53%, p = .017) and were more likely to see a specialist (34% vs. 17%) compared with those with limited literacy. Patients with limited health literacy were not more likely to see a chiropractor (7% vs. 7%), but reported more visits (19 vs. 8). CONCLUSIONS Patients with lower health literacy reported worse back and leg pain scores, indicating either more severe disease or a fundamental difference in their responses to standard health-related quality of life measures. This study also suggests that patients with limited health literacy may underutilize some resources and overutilize other resources. Further study is needed to clarify these patterns, and to examine their impact on health status and clinical outcomes.

BACKGROUND CONTEXT Scoli-RISK-1 is a multicenter prospective cohort designed to study neurologic outcomes following complex adult spinal deformity (ASD). The effect of unilateral versus bilateral postoperative motor deficits on the likelihood of long-term recovery has not been previously studied in this population. PURPOSE To evaluate whether bilateral postoperative neurologic deficits have a worse recovery than unilateral deficits. STUDY DESIGN Secondary analysis of a prospective, multicenter, international cohort study. METHODS In a cohort of 272 patients, neurologic decline was defined as deterioration of the American Spinal Injury Association Lower Extremity Motor Scores (LEMS) following surgery. Patients with lower extremity neurologic decline were grouped into unilateral and bilateral cohorts. Differences in demographics, surgical variables, and patient outcome measures between the two cohorts were analyzed. RESULTS A total of 265 patients had LEMS completed at discharge. Unilateral decline was seen in 32 patients (12%), while 29 (11%) had bilateral symptoms. At 2 years, there was no significant difference in either median LEMS (unilateral 50.0, interquartile range [IQR] 47.5–50.0; bilateral 50.0, IQR 48.0–50.0, p=.939) or change in LEMS from baseline (unilateral 0.0, IQR −1.0 to 0.0; bilateral 0.0, IQR −1.0 to 0.0, p=.920). In both groups, approximately two-thirds of patients saw recovery to at least their preoperative baseline by 2 years postoperatively (unilateral n=15, 63%; bilateral n=14, 67%). The mean Scoliosis Research Society-22R (SRS-22R) score at 2 years was 3.7±0.6 versus 3.2±0.6 (p=.009) for unilateral and bilateral groups, respectively. CONCLUSIONS The prognosis for neurologic recovery of new motor deficits following complex adult spinal deformity is similar with both unilateral and bilateral weaknesses. Despite similar rates of neurologic recovery, patient reported outcomes for those with bilateral motor decline measured by SRS-22R are worse at 2 years after surgery.

Study Design: Medicare database analysis. Objective: The purpose of this study was to investigate whether neurologic disorders represent a risk factor for revision after lumbar spine surgery. Methods: Patients who underwent lumbar spine surgery were identified from 5% Medicare Part B claims between 2005 and 2008. Cox regression analysis was used to evaluate risk factors for revision within the 7 years after the index lumbar surgery. Covariates included age, gender, race, census region, Medicare buy-in status, Charlson score, year, prior lumbar fusion within 2 years of index surgery, prior diagnosis of cervical spondylotic myelopathy treated with or without cervical spine surgery, and diagnoses of other neuromuscular conditions. Results: Of 8665 cases who had decompression only, 401 (5%) had a revision within 7 years after the index surgery. Factors predictive of revision were prior lumbar fusion (hazard ratio [HR] = 2.78, confidence interval [CI] = 1.43-5.37, P = .002) and being female (HR = 1.61, CI = 1.31-1.97, P < .001). Of 5501 cases who had a decompression and fusion, 752 (14%) had a revision surgery within 7 years after the index surgery. Factors predictive of revision were the presence of a neurologic disorder (HR = 1.24, CI = 1.05-1.46, P = .010), prior lumbar fusion (HR = 3.09, CI = 2.05-4.63, P < .001), and being female (HR = 1.35, CI = 1.15-1.57, P < .001). Conclusions: An increase in revision rate ( P = 0.01, HR = 1.24) was seen in patients with neurologic disorders undergoing lumbar decompression and fusion, although not for patients undergoing decompression alone. This suggests an opportunity to improve clinical outcome and reduce revision rate through improved surgical decision making or treatment of the neurologic disorder.

Study Design.Prospective, randomized, double-blinded, placebo-controlled clinical trial.Objective.To evaluate whether 90-day subcutaneous injections with 20 μg teriparatide increases the volume and quality of the fusion mass compared to placebo based on 12-month postop fine cut computed tomography scans. The secondary objective is to evaluate whether parathyroid hormone (PTH) increases fusion rates compared to placebo.Summary of Background Data.Few studies have investigated the effects of PTH on fusion in patients undergoing spinal arthrodesis. Early studies showed a more robust fusion mass with PTH after spinal fusion surgery. But the efficiency of PTH on noninstrumented spinal fusion surgery remains unclear.Methods.Patients with degenerative spondylolisthesis scheduled for noninstrumented posterolateral fusion were randomized to receive 90-day subcutaneous injections with 20 μg teriparatide (N = 41) or placebo (N = 46) in a 1:1 fashion. Fusion volume and quality was evaluated using 12-month postoperative fine cut computed tomography scans.Results.The two groups were comparable in terms of age, sex, and numbers of levels operated. PTH treatment was well tolerated but provided no additional benefit versus placebo. Fusion rates, the mean volume, and robustness of the fusion mass were similar between the PTH and placebo groups.Conclusion.Ninety-day subcutaneous administration of 20 μg teriparatide did not increase fusion volume or improve the quality of the fusion mass in elderly patients compared to placebo after noninstrumented spinal fusion surgery for degenerative spondylolisthesis.

STUDY DESIGN: Qualitative research using semistructured interviews.OBJECTIVE: To explore, from a patient perspective, factors influencing a patient's decision-making process and the decision to have surgery for lumbar disc herniation.SUMMARY OF BACKGROUND DATA: Since strong evidence favoring surgical over nonsurgical treatment is lacking and firm guidelines regarding the optimal timing of surgery are not available, it is essential to involve patients in the decision-making process. Thus the elements that might affect the decision-making process and the decision to have surgery must be identified.METHODS: Using a hermeneutic-phenomenological approach, 14 patients who were referred for primary surgery for lumbar disc herniation were interviewed. Interviews were transcribed and analyzed using a meaning-condensation method to identify themes influencing a patient's decision-making process and the decision to have surgery for lumbar disc herniation.RESULTS: Four main themes that could directly or indirectly influence the patients' decision-making process were identified: A) Patient information: patients' conceptions about treatment were not always based on sufficient information; B) Accelerated workflows: some patients needed time to process the information given, which may be limited due to accelerated workflows; C) Power imbalance: patients can be reluctant to challenge the system, as they do not want to offend, which can be seen as a power imbalance between clinicians and patients; and D) Personal past experience: experience, about treatment options from, i.e., close relatives, can impact patients thoughts about possible treatments.CONCLUSION: Several factors can influence patients' decision-making process and the decision itself: the amount and quality of information received as compared with their preconceived notions, the amount of time given to consider their decision, reluctance to challenge the system and offend the healthcare provider, and past personal experience. Understanding these complex factors will help clinicians to better support patients choosing between surgical and nonsurgical treatment for lumbar herniated disc.LEVEL OF EVIDENCE: 5.

An international, multicenter, ambispective, cohort study was completed to study effect of motor deficit on Health-related Quality of Life scores (HRQOLs) after adult spinal deformity surgery. HRQOLs were lower in patients who had more than 2 points of lower extremity motor score worsening. However, even these patients showed overall HRQOL improvement at 2 years., Study Design. International, multicenter, prospective, longitudinal observational cohort. Objective. To assess how new motor deficits affect patient reported quality of life scores after adult deformity surgery. Summary of Background Data. Adult spinal deformity surgery is associated with high morbidity, including risk of new postoperative motor deficit. It is unclear what effect new motor deficit has on Health-related Quality of Life scores (HRQOL) scores. Methods. Adult spinal deformity patients were enrolled prospectively at 15 sites worldwide. Other inclusion criteria included major Cobb more than 80°, C7–L2 curve apex, and any patient undergoing three column osteotomy. American Spinal Injury Association (ASIA) scores and standard HRQOL scores were recorded pre-op, 6 weeks, 6 months, and 2 years. Results. Two hundred seventy two complex adult spinal deformity (ASD) patients enrolled. HRQOL scores were worse for patients with lower extremity motor score (LEMS). Mean HRQOL changes at 6 weeks and 2 years compared with pre-op for patients with motor worsening were: ODI (+12.4 at 6 weeks and –4.7 at 2 years), SF-36v2 physical (–4.5 at 6 weeks and +2.3 at 2 years), SRS-22r (0.0 at 6 weeks and +0.4 at 2 years). Mean HRQOL changes for motor-neutral patients were: ODI (+0.6 at 6 weeks and –12.1 at 2 years), SF-36v2 physical (–1.6 at 6 weeks and +5.9 at 2 years), and SRS-22r (+0.4 at 6 weeks and +0.7 at 2 years). For patients with LEMS improvement, mean HRQOL changes were: ODI (–0.6 at 6 weeks and –16.3 at 2 years), SF-36v2 physical (+1.0 at 6 weeks and +7.0 at 2 years), and SRS-22r (+0.5 at 6 weeks and +0.9 at 2 years). Conclusion. In the subgroup of deformity patients who developed a new motor deficit, total HRQOLs and HRQOL changes were negatively impacted. Patients with more than 2 points of LEMS worsening had the worst changes, but still showed overall HRQOL improvement at 6 months and 2 years compared with pre-op baseline. Level of Evidence: 3

BACKGROUND CONTEXT The recent opioid crisis in the US highlights opioid related side-effects and the dire need to reduce opioid exposure with alternative approaches. Prior studies reported that as many as 25% of opioid naive patients undergoing lumbar fusion surgery are still consuming opioids at 2 years postoperative. Currently, opioids are a primary component of anesthesia during spinal surgery. We developed an opioid sparing anesthesia (OSA) protocol for lumbar spinal fusion surgery to mitigate opioid exposure. PURPOSE To compare surgical, peri- and postoperative process measures and in-hospital opioid consumption in patients receiving OSA vs traditional anesthesia. STUDY DESIGN/SETTING Retrospective, single center propensity-matched observational cohort study. PATIENT SAMPLE Patients who underwent 1-4 level lumbar fusion for degenerative conditions. OUTCOME MEASURES Daily and total opioid consumption in morphine milligram equivalents (MME). Methods Patients undergoing Results Of 143 OSA patients meeting inclusion criteria, 134 OSA patients were successfully propensity matched to 134 non-OSA patients. Consistent with propensity matching, there was no difference in baseline demographic parameters between cohorts. Patients undergoing OSA had reduced EBL (197mL vs 324mL, p=0.000) and OR time (153min vs 193min, p=0.000) compared to non-OSA. Emergence time (9.9min vs 11.6min, p=0.151) and PACU time (90min vs 88min, p=0.688) was similar between cohorts. There was no difference in LOS (3.3day vs 3.5 days, p=0.599). Daily opioid consumption was reduced from POD 1 (114MME vs 139MME, p=0.002) and maintained each day with decreased total consumption (195MME vs 272MME, p=0.002). Pain score on transfer out of PACU was decreased for OSA patients as well (4.8 vs 6.0, p=0.000). Conclusions In a matched comparison of OSA vs traditional anesthesia for 1-4 lumbar spinal fusions in degenerative conditions we found a reduction in EBL, OR Time, PACU pain scores, and daily/total opioid in hospital consumption. The findings of this pilot study justify ongoing efforts to optimize OSA and undertake larger prospective studies of OSA protocols. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

BACKGROUND CONTEXT Anterior cervical discectomy and fusion (ACDF), anterior cervical corpectomy and fusion (ACCF), and hybrids (combination ACCF-ACDF) are common procedures used to treat symptomatic cervical spondylosis. Although there is a relative abundance of literature comparing 1-level ACCF vs 2-level ACDF and 2-level ACCF vs 3-level ACDF, detailed comparisons of 3-level ACDF vs hybrid procedures have not been extensively addressed. PURPOSE The objective of this study is to compare 3 and 12-month radiographic sagittal parameters and patient reported outcomes (PROs) in patients who underwent 3-level ACDF or a hybrid procedure. STUDY DESIGN/SETTING Longitudinal observational comparative cohorts from a large, multisurgeon database. PATIENT SAMPLE Patients who underwent a 3-level ACDF (3L-ACDF, N=47) or 1-level corpectomy/1-level ACDF (Hybrid, N=52) with at least a 12-month postop data available were identified. OUTCOME MEASURES EuroQOL-5D (EQ-5D), Neck Disability Index (NDI), neck and arm pain. Methods Standard demographic, surgical and (PROs) were collected in addition to pre- and postoperative radiographic data including C2 plumb line (C2PL), C2-C7 lordosis (CL), segmental lordosis (SL), and T1 slope (T1S). Results The two cohorts were similar in terms of demographics at baseline. At 3 months postop, CL (9.04°vs -2.12°, p=0.00) and SL (6.06°vs -2.26°, p=0.003) were significantly greater in the 3L-ACDF group versus the HYBRID group. This significant difference was maintained at 12 months postop for CL (6.62°vs -0.60°, p=0.015) but not for SL (2.36°vs -1.09°, p=0.199). There were no differences in PROs between the two groups prior to surgery, at 3 months postop, or at 12 months postop. Seven patients required revision surgery in the 1-year study period (1 in the 3L-ACDF, and 6 in the Hybrid p Conclusions Three-level ACDF resulted in greater C2-C7 lordosis and segmental lordosis postoperatively, which was maintained at 1 year for cervical lordosis. While patient reported outcomes were similar between the groups, patients with hybrid instrumentation required significantly more revision surgeries than those treated with 3-level ACDF. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.

Study Design: Longitudinal cohort study. Objectives: To investigate whether a cutoff point in leg pain intensity measured preoperatively or at early follow-up could identify patients at risk of poor outcomes in terms of disability at 1-year and 2-year follow-up after first-time lumbar discectomy, and to identify the characteristics associated with early postoperative leg pain intensity. Methods: From 2010 to 2013, 556 patients underwent lumbar discectomy. Leg pain intensity was measured preoperatively and at early postoperative follow-up and dichotomized according to an established cutoff point on a 0 to 100 visual analogue scale (mild Results: Moderate/severe leg pain intensity at early follow-up showed a statistically significant association with higher ODI at 1-year and 2-year follow-up compared to mild leg pain intensity (median [interquartile range]: 24 [26] and 26 [26] versus 12 [18] and 10 [20], respectively). Patients reporting moderate/severe leg pain intensity were more often smokers, were more prone to receive social benefits, and were more prone to have chronic back pain. The preoperative measurement of leg pain intensity showed inferior associations. Conclusion: The proposed cutoff point in leg pain intensity at early follow-up can identify patients at risk of disability at both 1-year and 2-year follow-up after first-time discectomy. Future research should be undertaken to investigate whether patients with moderate/severe leg pain intensity at early postoperative follow-up could benefit from additional or more intensive postoperative interventions.