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Background: The use of modern rigid instrumentation in pediatric cervical fusions decreases the risk of implant-related complications, both acute and long term. However, previous studies have indicated that acute implant-related issues still occur in the adult population. Reports of pediatric acute implant complications, occurring within 3 months of surgery, are under-represented in the literature. The purpose of this study is to document the prevalence of acute implant-related complications in a pediatric cervical fusion population., Methods: A retrospective review of instrumented cervical fusions from August 2002 to December 2018 was conducted. Acute implant-related complications were defined as malposition, fracture, or disengagement of cervical instrumentation, including screws, rods, and plates, within 90 days of surgery., Results: A total of 166 cases were included (55% male individuals) with an average age at surgery of 12.5 years (SD, ±5.28). Acute implant-related complications occurred in 5 patients (3%). All 5 patients had a syndromic diagnosis: Loeys-Dietz (n=1), osteopetrosis (n=1), neurofibromatosis (n=1), trisomy 20 (n=1), and achondroplasia (n=1). One case involved asymptomatic screw protrusion, 1 case lateral mass screw pull-out, 2 more had screw-rod disengagement, and the last experienced dislodgement of the anterior plate. The median time until the presentation was 25 days (range, 1 to 79 d). All patients (n=5) required surgical revision., Conclusions: This case series suggests that the overall incidence of acute cervical implant failure is low. However, failure is more likely to occur in patients with underlying syndromes compared with patients with different etiologies. Intraoperative use of 3-dimensional computed tomography imaging is recommended to evaluate the screw position and potentially avoid later surgery.

Study Design: Retrospective multi-center enrollment., Objective: To examine the impact of patient and surgical factors on proximal complication and revision rates of early onset scoliosis patients using a multicenter database. Proximal anchor pullout and junctional kyphosis are common causes necessitating revision surgery during growth friendly treatment of early onset scoliosis (EOS). Many options exist for proximal fixation and may impact the rate of these complications., Methods: Retrospective review of multicenter database of patients with growth friendly constructs for EOS. Inclusion criteria were patients with index instrumentation < 10 years of age and minimum of 2 year follow-up., Results: 353 patients met the inclusion criteria and had the following constructs: growing rods with spine anchors = 303; growing rods with rib anchors = 15 and VEPTR = 35. Mean age at index instrumentation was 6.0 years. Mean preoperative Cobb angle was 76° and mean kyphosis was 54°. Mean follow-up was 6.0 years. 21.8% of patients (77/353) experienced anchor pullout. Lower anchor pullout rates were associated with a higher numbers of proximal anchors (p = 0.003, r = - 0.157), and 5 or more anchors were associated with lower rates of anchor pullout (p = 0.014). Anchor type (rib hooks vs spine anchors vs rib cradle) did not impact rate of anchor pullout (p = 0.853). Kyphosis data was available for 198 patients. 23.2% (46/198) of these patients required proximal extension of their construct after index surgery. Initial instrumentation below the upper end vertebrae (UEV) of kyphosis was associated with higher rates of subsequent proximal revision; 28.9% (20/69) compared to 20.1% (26/129) for those instrumented at or above the UEV (p = 0.035). Preoperative kyphosis and change in thoracic kyphosis were not associated with anchor pullout (p = 0.436, p = 0.115) or proximal revision rates (p = 0.486, p = 0.401)., Conclusion: Five or more anchors are associated with lower rates of anchor pullout. Proximal anchor placement at or above the UEV resulted in a significant decrease in rates of proximal extension of the construct.

Study Design: Retrospective case series., Objective: To report the effect of repeated growing rod (GR) lengthenings on the sagittal and pelvic profile in patients with early-onset scoliosis., Summary of Background Data: Posterior distraction-based GRs have gained popularity as a technique for the surgical management of early-onset scoliosis. However, there are no published studies on the effect of serial GR lengthenings on sagittal balance, thoracic kyphosis (TK), lumbar lordosis (LL), and pelvic parameters., Methods: We retrospectively reviewed data from a multicenter early-onset scoliosis database. Forty-three patients who were able to walk with minimum 2-year follow-up who underwent single- or dual-GR surgery were included for review. Mean number of lengthenings was 6.4 (range, 3-16). Mean preoperative age was 5.6 years (standard deviation, 2.4 yr), and mean follow-up was 3.5 years. Maximum TK, LL, and sagittal balance were assessed preoperatively, after index surgery, and at the latest follow-up., Results: There was a significant decrease both in TK and LL after index surgery, which then increased during the lengthening period. There was a significant increase in both proximal junctional kyphosis and distal junctional angle. Pelvic parameters (pelvic tilt, pelvic incidence, sacral slope) were unchanged during the treatment period. Significant improvement was observed in sagittal balance. There was a correlation between the change in TK and change in LL., Conclusion: TK decreased after index surgery and increased between the index surgery and the latest follow-up, which was accompanied by an increase in LL. All-screw proximal constructs had mean 9° more proximal junctional kyphosis than all-hook proximal constructs. An increase in proximal junctional kyphosis and distal junctional angle was found during the treatment period. Although there was an independent effect of number of lengthenings on TK, there was no significant detrimental effect on other sagittal spinopelvic parameters. GRs had a positive effect on sagittal vertical axis, which returned patients to a more neutral alignment through the course of treatment., Level of Evidence: 4.

Study Design: Retrospective analysis of patients with spinal muscular atrophy (SMA) treated with growing rod (GR) instrumentation for scoliosis., Objective: To evaluate structural effectiveness, complications, and length of hospital stay associated with GRs for scoliosis in SMA and to compare values with those of infantile and juvenile idiopathic scoliosis (IIS/JIS)., Summary of Background Data: Most studies evaluate GR effectiveness in all patients. We specifically examined SMA and IIS/JIS., Methods: We searched a multicenter database and found 15 patients with SMA and scoliosis treated with GRs for 54 ± 33 months. Radiographic measurements, complications, and hospital stay durations were compared with those of 80 GR patients with IIS/JIS observed for 43 ± 31 months. Measures of rib collapse, including T6:T10 mean rib-vertebral angle and T6:T12 thoracic width, were compared. Student t test was used to compare SMA and IIS/JIS values (significance level, P = 0.05)., Results: Primary radiographic measurements in patients with SMA improved from preoperative to latest follow-up as follows: curve, 89° ± 19° to 55° ± 17°; pelvic obliquity, 31° ± 14° to 11° ± 10°; space-available-for-lung ratio, 0.86 ± 0.15 to 0.94 ± 0.21; and T1-S1 length grew 8.7 ± 3.2 cm. Rib collapse continued despite GR treatment in SMA but not in IIS/JIS. Hospital stays were longer for SMA than for IIS/JIS for lengthening procedures (P = 0.01) and trended to be longer for initial surgery (P = 0.08) and final fusion (P = 0.06). Patients with SMA and IIS/JIS experienced, respectively, 0.5 and 1.1 major complications per patient (P = 0.02)., Conclusion: GRs improve trunk height and the space-available-for-lung ratio while controlling curve and pelvic obliquity in young patients with SMA with severe scoliosis, but they do not halt rib collapse. For patients with SMA, hospital stays were longer than those for patients with IIS/JIS, whereas the rate of major complications was lower.

Study Design: Retrospective review., Objective: To analyze outcomes and complications of growing rods fixed to the pelvis., Summary of Background Data: Growing systems with pelvic foundations are used for neuromuscular/syndromic scoliosis. There is little data comparing different constructs. This project analyzed the outcomes and complications of this population., Methods: Records/radiographs of 36 patients from the Growing Spine database with growing rods anchored in the pelvis were studied. Diagnoses included spinal muscular atrophy-6, cerebral palsy-5, myelomeningocele-5, congenital-4, arthrogryposis-1, and miscellaneous/syndromic-15. Age at surgery was 6.8 +/- 3 years. Preoperative curve was 86 degrees +/- 22 degrees and pelvic obliquity was 27 degrees +/- 11 degrees . Follow-up was 40 +/- 23 months. Rod breakage rate was compared to that of 299 patients not fixed to the pelvis., Results: Iliac screws were used in 20 patients, iliac rods in 10, S-rods in 3, and sacral fixation in 6. Dual rods were used in 30 patients; single in 6. At follow-up, mean Cobb improved to 48 degrees +/- 20 degrees and pelvic obliquity improved to 11 degrees +/- 7 degrees . Iliac screws achieved significantly better Cobb and pelvic obliquity correction than sacral fixation (47% vs. 29%, P = 0.04, 66% vs. 40%, P = 0.001). Pelvic obliquity correction exceeded major curve correction (P < 0.001). Total gain in T1-S1 length was 8.6 +/- 4.3 cm; gain during lengthenings was 4.0 +/- 4.7 cm. Bilateral rods provided better correction of both pelvic obliquity (67% vs. 44%, P = 0.006) and major curve (47% vs. 25%, P = 0.02) than unilateral rods. Six patients have undergone final fusion at mean 3.3 +/- 1.8 years after initial surgery. Five patients developed deep infections. There were 6 rod breakages; this rate did not differ from constructs not anchored in the pelvis (P = 0.36). There were 5 breakages of iliac screws and none of other anchors (P = 0.035)., Conclusion: Growing rods can include pelvic fixation to correct pelvic obliquity or obtain adequate fixation. Dual iliac fixation provides the best correction. Both iliac screws and rods provide satisfactory distal fixation; iliac screws had a higher rate of breakage. Growing rods with pelvic fixation are effective in deformity correction and achieving growth.

Study Design: Retrospective review., Objective: To evaluate the effectiveness of a new growing rod technique in controlling infantile scoliosis in patients with Marfan syndrome., Summary of Background Data: Infantile scoliosis in patients with Marfan syndrome is nearly always progressive and poorly controlled by bracing, yet previous studies have shown poor results with first-generation extensible spinal rod techniques., Methods: Ten patients with Marfan syndrome and scoliosis developing before 3 years of age were treated with growing rods (3 single, 7 dual). Mean age at initial surgery was 5.3 years (SD, 2.7 years). Before surgery, the mean curve was 77.2 degrees (SD, 15.6 degrees ) and the mean thoracolumbar kyphosis was 56 degrees (SD, 21 degrees ). Patients on warfarin sodium were lengthened at yearly intervals; others, more frequently. Mean follow-up was 87 months (SD, 30.5 months)., Results: Mean curve correction was 51% (SD, 23%) overall, 31% (SD, 23%) for single rods, and 60% (SD, 19%) for dual rods. Mean coronal and sagittal imbalance improved from 56 to 18 mm and from 31 to 21 mm, respectively. The mean length obtained was 11.5 cm (SD, 3.6 cm) overall and 11.2 cm (SD, 3.60 cm) for the 5 patients with final fusion. Complications included 2 rod breakages and 3 intraoperative dural leaks. There was 1 anchor dislodgement and no postoperative dural leak. No patient developed clinically noteworthy junctional kyphosis. One patient died of unrelated causes 3 months after surgery., Conclusion: As life expectancy improves for patients with neonatal Marfan syndrome, spinal deformity becomes an important issue. Extensible spinal growing rods are an effective solution to the problem. Dual rods appear to be more corrective than single rods. Substantial spinal length can be obtained to minimize trunk disproportion. Growing rods may help prevent large infantile curves from becoming severe in Marfan syndrome, allowing definitive spinal fusion closer to skeletal maturity.

Study Design: Cross-sectional study of 37 patients to measure serum levels of nickel and chromium after posterior spinal arthrodesis using stainless steel implants., Objectives: To investigate the relationship between factors such as age, gender, pain, time from surgery, length of arthrodesis, and level of arthrodesis to serum metal ion levels after instrumented spinal arthrodesis., Summary of Background Data: Measurable levels of metal ions in the serum can be detected after the use of stainless steel implants. There is some evidence to suggest that long-term exposure can potentially be toxic. Posterior spinal arthrodesis with stainless steel implants is a common procedure to treat spinal deformity in the adolescent population; however, the extent of metal ion exposure after posterior spinal arthrodesis is unknown., Methods: Patients that underwent posterior instrumented spinal arthrodesis with more than 6 months follow-up were recruited for this study. Patients with altered neurologic function were excluded. Serum levels of nickel and chromium were measured using inductively coupled plasma mass spectrometry. Pain was assessed using the Oswestry questionnaire. Spine radiographs were used to look for evidence of pseudarthrosis. Forty-five patients were approached, and 37 agreed to the questionnaire and blood test. Ten patients were men and 27 were women. Mean age at surgery was 14 years with mean follow-up of 6 years. Statistical correlations between serum metal ion levels and age at surgery, time from surgery, gender, number of segments fused, spinal instrument interfaces, pain, and instrumentation type were assessed., Results: Abnormally high levels of nickel and chromium above normal levels (0.3 ng/mL for nickel, 0.15 ng/mL for chromium) could be detected in serum after posterior spinal arthrodesis using stainless steel implants. There was a significant inverse correlation between serum nickel (r = -0.61, P < 0.001) and chromium (r = -0.64, P < 0.001) levels and time from surgery. When patients were grouped based on lengths of time from surgery, 0 to 2 years (n = 7), 2 to 4 years (n = 11), and >4 years (n = 8), the mean +/- SD for nickel (ng/mL) was 3.8 +/- 2.6, 1.3 +/- 1.1, and 0.9 +/- 0.8, respectively. Analysis ofvariance revealed significant group differences (P =0.004). Similarly, the chromium levels were 2.7 +/- 2.7, 0.6 +/- 0.4, and 0.3 +/- 0.3, respectively (P = 0.018). Only time from surgery was a significant multivariate predictor of nickel and chromium serum levels. Pseudarthrosis was not seen in this cohort., Conclusions: Elevated levels of nickel and chromium can be measured after posterior instrumented spinal arthrodesis. The levels diminish rapidly with time from surgery but still remained above normal levels 4 years after surgery. Long-term implication of this metal ion exposure is unknown and should be studied further.

Study Design: A retrospective radiographic and chart review of patients who underwent operative treatment with the use of reduced size spinal instrumentation for congenital spine deformities, Objective: To assess the safety and efficacy of spinal instrumentation in young patients who were operated on for a congenital spine deformity., Summary of Background Data: The use of spinal instrumentation has been shown to improve curve correction and arthrodesis rates in spinal deformity surgery. The advent of reduced-size implants has allowed surgeons to expand the use of instrumentation in pediatric patients. The use of reduced-size spinal instrumentation in children with congenital spine deformities has not been well documented., Methods: We retrospectively investigated the use of spinal instrumentation in 40 patients younger than 8 years with a congenital spine deformity. The review of radiographs and medical records was performed to assess the complications associated with instrumentation, the curve correction, and the arthrodesis rate in this patient population., Results: The complications associated with the use of instrumentation in this group of patients were infrequent. Curve correction was excellent, and the sagittal profile was maintained in all patients at an average follow-up of greater than 3 years. All patients obtained a solid arthrodesis., Conclusions: The use of reduced-size spinal instrumentation in young patients is safe and efficacious. Curve correction, length of immobilization, and fusion rate are improved compared to similar patients in the literature treated without instrumentation.

Study Design: A retrospective assessment of the effectiveness of lumbar pedicle screws versus laminar hooks in lumbar curve correction with double major curves in adolescent idiopathic scoliosis., Objective: To determine if pedicle screw fixation of the lumbar spine has any advantage compared with multiple laminar hook instrumentation in the treatment of double major curves in adolescent idiopathic scoliosis., Summary of Background Data: Although hooks have been used most commonly, pedicle screws may offer advantages in correction and maintenance of reduction of the lumbar curve in adolescent idiopathic scoliosis., Methods: A consecutive series of 39 patients with double major curves underwent thoracic and lumbar instrumentation by a single surgeon. Lumbar pedicle screws and hooks were used in 20 patients (Group S) and in 19 patients only lumbar hooks were used (Group H). Thoracic Cotrel-Dubousset instrumentation with hooks was the same in both groups. Preoperative age, gender, bracing, and Cobb angles were similar in both groups. Preoperative, 1-month postoperative, and latest follow-up standing posteroanterior and lateral spine radiographs were blinded to the surgeon and lumbar instrumentation covered to hide its identity. Measurements included Cobb angles, preoperative flexibility, lumbar and thoracic apical vertebral deviation, and reduction of lateral tilt and lateral displacement of the first free lumbar vertebra below the instrumentation. Percent correction, maintenance of correction at follow-up, and total levels fused were calculated., Results: The mean follow-up was 3.5 years (range, 2-8 years), which was similar for Groups H and S. Pedicle screws appear to offer some advantage in lumbar curve correction, maintenance of correction, and correction of the uninstrumented spine below the fusion when compared with the use of hooks alone. Horizontalization of the first free lumbar vertebra below the instrumentation percent correction of tilt: 62% screws vs. 11% hooks; P = 0.0003), residual tilt (8 degrees screws vs. 17 degrees hooks; P = 0.004), and loss of horizontalization at follow-up (5% screws vs. 26% hooks) were dramatically better for the group using screws. Lumbar curve correction (72% screws vs. 60% hooks; P = 0.026), loss of lumbar curve correction (5% screws vs. 13% hooks), and correction of lateral apical vertebral deviation (2.2-cm screws vs. 1.5-cm hooks or 63% vs. 31%; P = 0.013) were better when screws were used. There was no significant difference in loss of correction of the thoracic curves (35% vs. 37%) or any difference in loss of correction of lateral displacement of the thoracic apical vertebra (12% vs. 14%). There was no difference in total levels fused, operative blood loss, operative time, or ultimate patient outcome. No patients in either group had spinal imbalance at latest follow-up. There were no complications related to pedicle screw placement. Two cases of transient postoperative superior mesenteric artery syndrome (duodenal obstruction by the superior mesenteric artery) in the pedicle screw group are attributed to acute correction of the lumbar scoliosis and thoracolumbar kyphosis with resultant lordosis at the thoracolumbar junction., Conclusions: Lumbar pedicle screws may offer greater lumbar curve correction, better maintenance of correction, and greater correction of the uninstrumented spine below double major curves. No complications were associated with the placement of pedicle screws.