Do Caregivers and Patients With Early-Onset Scoliosis Share the Same Perspective on Health-Related Quality of Life? A Comparison of 24-item Early-Onset Scoliosis Questionnaire and 22-item Scoliosis Research Society Questionnaire Scores.

OBJECTIVE: The 24-item Early-Onset Scoliosis Questionnaire (EOSQ-24) is validated in patients with early onset scoliosis (EOS) aged 0 to 18 years and the 22-item Scoliosis Research Society (SRS-22) questionnaire is validated in idiopathic scoliosis patients 10 years and older. EOSQ-24 is completed by the caregiver and SRS-22 is completed by the patient. A prior study comparing patient-reported outcome measures completed by older pediatric patients and their parents showed a low level of agreement. Our purpose was to compare EOSQ-24 and SRS-22 scores completed at the same time point and at subsequent time points, in patients aged 5 to 18 years with idiopathic or congenital EOS without developmental delay. METHODS: This was a multicenter retrospective study. We identified pairs of EOSQ-24 and SRS-22 completed on the same day or within 6 months. Some patients had multiple pairs of surveys over time. EOSQ-24 and SRS-22 questions were matched and domain scores for Pain, Function, Mental Health, and Satisfaction were compared. Patients with a change in treatment between surveys were excluded. Pearson correlation coefficients ( r ) were used to compare domain scores, with r ≥0.7 indicating a strong relationship. RESULTS: There were 228 patient-caregiver dyads who completed 411 pairs of EOSQ-24 and SRS-22 on the same day. A strong correlation was found only for the Pain domain ( r =0.77). Function, Mental Health, and Satisfaction domains had positive but not strong correlations ( r = 0.58, r = 0.50, r = 0.41, respectively). Subanalysis based on age also showed a strong correlation only for Pain. There were 76 patient-caregiver dyads who completed 134 pairs of surveys with SRS-22 completed within 6 months after an EOSQ-24. All domains demonstrated a positive but not strong correlation, with Pain showing the highest correlation ( r = 0.64). CONCLUSIONS: EOSQ-24 and SRS-22 had a strong correlation only for Pain when completed at the same time point. EOSQ-24 and SRS-22 completed within 6 months lacked a strong correlation for all domains. Our findings suggest that parents and children with EOS may not share the same perspective on their health. Self-reported questionnaires should be used when possible to assess health-related quality of life in older children and adolescents with EOS who are developmentally neurotypical. LEVEL OF EVIDENCE: Level III-diagnostic.

Incidence of Tether Breakage in Anterior Vertebral Body Tethering.

BACKGROUND: Thoracic anterior vertebral body tethering (TAVBT) is an emerging treatment for adolescent idiopathic scoliosis. Tether breakage is a known complication of TAVBT with incompletely known incidence. We aim to define the incidence of tether breakage in patients with adolescent idiopathic scoliosis who undergo TAVBT. The incidence of tether breakage in TAVBT is hypothesized to be high and increase with time postoperatively. METHODS: All patients with right-sided, thoracic curves who underwent TAVBT with at least 2 and up to 3 years of radiographic follow-up were included. Tether breakage between 2 vertebrae was defined a priori as any increase in adjacent screw angle >5 degrees from the minimum over the follow-up period. The presence and timing of tether breakage were noted for each patient. A Kaplan-Meier survival analysis was performed to calculate expected tether breakage up to 36 months. χ 2 analysis was performed to examine the relationship between tether breakage and reoperations. Independent t test was used to compare the average final Cobb angle between cohorts. RESULTS: In total, 208 patients from 10 centers were included in our review. Radiographically identified tether breakage occurred in 75 patients (36%). The initial break occurred at or beyond 24 months in 66 patients (88%). Kaplan-Meier survival analysis estimated the cumulative rate of expected tether breakage to be 19% at 24 months, increasing to 50% at 36 months. Twenty-one patients (28%) with a radiographically identified tether breakage went on to require reoperation, with 9 patients (12%) requiring conversion to posterior spinal fusion. Patients with a radiographically identified tether breakage went on to require conversion to posterior spinal fusion more often than those patients without identified tether breakage (12% vs. 2%; P =0.004). The average major coronal curve angle at final follow-up was significantly larger for patients with radiographically identified tether breakage than for those without tether breakage (31 deg±12 deg vs. 26 deg±12 deg; P =0.002). CONCLUSIONS: The incidence of tether breakage in TAVBT is high, and it is expected to occur in 50% of patients by 36 months postoperatively. LEVEL OF EVIDENCE: Level IV.

Posterior cervical spinal fusion in the pediatric population using modern adult instrumentation - clinical outcome and safety.

PURPOSE: Traditionally, less rigid fixation techniques have been applied to the pediatric cervical spine. There is a lack of long-term outcome data for rigid fixation techniques. The purpose of this study was to define the clinical outcome and safety of posterior instrumented fusion in the pediatric population using adult posterior instrumentation. METHODS: A multicenter, retrospective review of pediatric patients who underwent posterior cervical fusion using a 3.5 mm posterior cervical system for any indication was performed. Outcome parameters included complications, revision and fusion rates, operative time (OR), blood loss, and postoperative neurologic status. Outcomes were compared between patient groups (posterior only versus anterior/posterior approach, short versus intermediate versus long fusion, and between different etiologies) using Mann-Whitney and chi-square test. RESULTS: Seventy-nine patients with a mean age of 9.9 years and mean follow-up of 2.8 years were included. At baseline 44 (56%) had an abnormal neurologic exam. Congenital deformities and basilar invagination were the most common indications for surgery. Posterior-only surgery was performed in 71 (90%) cases; mean number of levels fused was 4 (range 1-15). Overall, 4 (5%) operative complications and 4 (5%) revisions were reported at an average postoperative time of 2.6 years. Neurologic status remained unchanged in 74%, improved in 23%, and worsened in 3%. When comparing outcome measures between the various groups, 2 significant differences were found: OR was longer in the anterior/posterior approach group and decline of neuro status was more frequent in the long fusion group. CONCLUSION: Posterior cervical fusion with an adult 3.5 mm posterior cervical system was safe in this cohort of 79 pediatric patients irrespective of surgical technique, fusion length, and etiology, resulting in a high fusion and low complication/revision rate.

Operative differences for posterior spinal fusion after vertebral body tethering: Are we fusing more levels in the end?

PURPOSE: Little is known about the perioperative characteristics associated with a posterior spinal fusion (PSF) in adolescent idiopathic scoliosis patients previously treated with vertebral body tethering (VBT). We aimed to determine if operative time, estimated blood loss, postoperative length of stay, instrumentation type, and implant density differed in patients that received a PSF (i.e., PSF-Only) or a PSF following a failed VBT (i.e., PSF-VBT). METHODS: We retrospectively assessed matched cohort data (PSF-VBT = 22; PSF-Only = 22) from two multi-center registries. We obtained: (1) operative time, (2) estimated blood loss, (3) postoperative length of stay, (4) instrumentation type, and (5) implant density. Theoretical fusion levels prior to the index procedure were obtained for PSF-VBT and compared to the actual levels fused. RESULTS: We observed no difference in operative time, estimated blood loss, or postoperative length of stay. Instrumentation type was all-screw in PSF-Only and varied in PSF-VBT with nearly 25% of patients exhibiting a hybrid construct. There was no added benefit to removing anterior instrumentation prior to fusion; however, implant density was higher in PSF-Only (1.9 ± 0.2) than when compared to PSF-VBT (1.7 ± 0.3). An additional two levels were fused in 50% of PSF-VBT patients, most of which were added to the distal end of the construct. CONCLUSIONS: We found that operative time, estimated blood loss, and postoperative length of stay were similar in both cohorts; however, the length of the fusion construct in PSF-VBT is likely to be two levels longer when a failed VBT is converted to a PSF.

Vertebral Body Tethering: Rationale, Results, and Revision.

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

Use of Vancomycin Powder in Spinal Deformity Surgery in Cerebral Palsy Patients is Associated With Proteus Surgical Site Infections.

PURPOSE: Surgical site infection (SSI) rates in pediatric spinal deformity surgery for cerebral palsy (CP) patients are higher than that in idiopathic scoliosis. The use of vancomycin powder is associated with decreased risk of SSI in neuromuscular patients. Prior studies in adult and pediatric early-onset scoliosis patients have shown that vancomycin powder alters microbacterial profile in patients that develop SSI. However, the effects of topical vancomycin powder on microbiology in spinal deformity surgery for CP patients has not been studied. METHODS: An international multicenter database of CP neuromuscular scoliosis patients was used in this retrospective cohort study. All patients that underwent posterior spinal instrumented fusion for CP neuromuscular scoliosis from 2008 to 2019 were queried, and 50 cases complicated by postoperative SSI were identified. Intraoperative antibiotic details were documented in 49 cases (98.0%). Microbiology details were documented in 45 cases (91.8%). Microbiology for patients that received topical vancomycin powder were compared with patients that did not. A multivariate regression model was used to control for potential confounders. RESULTS: There were 45 patients included in this study. There were 27 males (60.0%) and 18 females (40.0%). Mean age at surgery was 14.8±2.4 years. There were 24 patients that received topical vancomycin powder (53.3%). The mean time from index surgery to SSI was 4.3±11.3 months.On univariate analysis of microbiology cultures by vancomycin powder cohort, there were no significant differences in culture types. Proteus spp. trended on significance with association with vancomycin powder use (P=0.078). When controlling for potential confounders on multivariate analysis, intraoperative topical vancomycin powder was associated with increased risk for proteus infection (adjusted odds ratio: 262.900, 95% confidence interval: 1.806-38,267.121, P=0.028). DISCUSSION: In CP patients undergoing pediatric spinal deformity surgery, the use of vancomycin powder was independently associated with increased risk for proteus infections. Further study into antibiotic regimens for spinal deformity surgery in the CP population should be performed. LEVEL OF EVIDENCE: Level III-retrospective cohort study.

Best Practice Guidelines for Surgical Site Infection in High-risk Pediatric Spine Surgery: Definition, Prevention, Diagnosis, and Treatment.

BACKGROUND: Prior "best practice guidelines" (BPG) have identified strategies to reduce the risk of acute deep surgical site infection (SSI), but there still exists large variability in practice. Further, there is still no consensus on which patients are "high risk" for SSI and how SSI should be diagnosed or treated in pediatric spine surgery. We sought to develop an updated, consensus-based BPG informed by available literature and expert opinion on defining high-SSI risk in pediatric spine surgery and on prevention, diagnosis, and treatment of SSI in this high-risk population. MATERIALS AND METHODS: After a systematic review of the literature, an expert panel of 21 pediatric spine surgeons was selected from the Harms Study Group based on extensive experience in the field of pediatric spine surgery. Using the Delphi process and iterative survey rounds, the expert panel was surveyed for current practices, presented with the systematic review, given the opportunity to voice opinions through a live discussion session and asked to vote regarding preferences privately. Two survey rounds were conducted electronically, after which a live conference was held to present and discuss results. A final electronic survey was then conducted for final voting. Agreement ≥70% was considered consensus. Items near consensus were revised if feasible to achieve consensus in subsequent surveys. RESULTS: Consensus was reached for 17 items for defining high-SSI risk, 17 items for preventing, 6 for diagnosing, and 9 for treating SSI in this high-risk population. After final voting, all 21 experts agreed to the publication and implementation of these items in their practice. CONCLUSIONS: We present a set of updated consensus-based BPGs for defining high-risk and preventing, diagnosing, and treating SSI in high-risk pediatric spine surgery. We believe that this BPG can limit variability in practice and decrease the incidence of SSI in pediatric spine surgery. LEVEL OF EVIDENCE: Not applicable.

Factors associated with surgical approach and outcomes in cerebral palsy scoliosis.

BACKGROUND: Neuromuscular scoliosis is often treated with posterior spinal fusion, with or without anterior release, and either a same-day or staged, 2-day procedure. METHODS: We retrospectively reviewed 222 patients from a prospectively collected, multi-center database of patients with cerebral palsy scoliosis with 2-year follow-up. Baseline characteristics, perioperative, radiographic, and HRQoL measures were compared in six sub-analyses: (1) staged versus same-day surgeries, (2) posterior-only fusion (PSF) versus anterior-posterior spinal fusion (APSF), (3) same-day versus staged PSF, (4) staged versus same-day APSF, (5) same-day PSF versus same-day APSF, (6) staged PSF versus staged APSF. RESULTS: Staged patients had larger curves and more pelvic obliquity, longer anesthesia and surgical times, longer hospital and ICU stays (p < 0.001), and more days intubated (p = 0.021). The staged PSF group had larger curves (p = 0.006), longer anesthesia (p = 0.020) and surgeries (p = 0.007), hospital (p = 0.009) and ICU stays (p = 0.028) compared to same-day PSF. The staged APSF group had longer hospital (p < 0.001) and ICU stays (p = 0.004) and anesthesia and surgeries (p < 0.001). Same-day APSF was associated with larger curves (p < 0.002), longer anesthesia (p = 0.012) and surgeries (p = 0.042), greater residual curves (p = 0.035), and greater absolute correction (p = 0.007) compared to same-day PSF. The staged APSF group had longer anesthesia times (p < 0.001) compared to the staged PSF group. No sub-analysis revealed significant differences in baseline characteristics, complications, or HRQoL. CONCLUSION: Staged and circumferential approaches tend to be used for greater deformity, but were not associated with superior deformity correction, and were associated with longer operative time, hospital stays, ICU stays, and days intubated. However, for the most severe deformity, other patient factors may play more important roles in treatment decisions given that patients treated with a staged PSF or an APSF, whether staged or not, were similar at baseline. LEVEL OF EVIDENCE: III. These slides can be retrieved under Electronic Supplementary Material.

L3 translation predicts when L3 is not distal enough for an "ideal" result in Lenke 5 curves.

PURPOSE: Determining whether to fuse a Lenke 5 curve to L3 or to L4 is often a difficult decision. The purpose of this study was to determine preoperative variables predictive of an "ideal" or "less than ideal" outcome for Lenke 5 curves instrumented to L3. METHODS: A multicentre registry of adolescent idiopathic scoliosis patients was queried for surgically treated Lenke 5 curves with a lowest instrumented vertebra (LIV) of L3 and minimum 2 years of follow-up. Five seasoned surgeons qualitatively rated the 2-year postoperative images as "ideal" or "less than ideal" with respect to correction and alignment. Preoperative and postoperative radiographic variables were compared between the two groups. Multivariate regression analysis was performed to determine variables most predictive of a "less than ideal" outcome. RESULTS: One hundred and thirty-nine patients met criteria. Twenty-three were considered "less than ideal" by ≥ 3 surgeons; 81 were unanimously "ideal". Preoperatively, the "less than ideal" group had significantly stiffer curves, greater apical translation, and greater LIV angulation and translation. Multivariate regression found that preoperative L3 translation (p = 0.009) was the single most important predictor of a "less than ideal" outcome: < 3.5 cm consistently resulted in an "ideal" outcome, while > 3.5 cm risked a "less than ideal" result. CONCLUSION: While multiple variables are important in achieving an "ideal" outcome in Lenke 5 curves, this study found preoperative L3 translation was the most important predictor of success with an L3 translation < 3.5 cm being a potential threshold for selecting L3 as the LIV. These slides can be retrieved under Electronic Supplementary Material.

Progressive decline in pulmonary function 5 years post-operatively in patients who underwent anterior instrumentation for surgical correction of adolescent idiopathic scoliosis.

PURPOSE: To evaluate changes in pulmonary function tests (PFT) at 5 years post-operatively in patients with adolescent idiopathic scoliosis (AIS) and to determine whether these changes are progressive or static after 2 years. METHODS: AIS surgical patients with pre-operative and 5 year post-operative forced expiratory volume (FEV) and forced vital capacity (FVC) were included. The percentage of patients with pulmonary impairment at 5 years was calculated. Repeated measures ANOVA was used to evaluate changes between pre-operative PFT and 5 years post-operative PFT and to determine whether the changes differed between curve types and approach. A sub-analysis of patients with 2 year data was performed to determine whether PFT changes were static or progressive. RESULTS: Two hundred and sixty-two patients had undergone pre-operative and 5 year post-operative PFTs. At 5 years, 42% were normal, 41% had mild impairment, and 17% had moderate-severe impairment. Overall, there was a decline in % predicted FVC (p < 0.05); FEV remained stable. There was no difference based on major curve type (p > 0.05). Anterior instrumentation cases declined significantly between pre-operative PFT and 5 years post-operative PFT (FEV: - 10% open, - 6% thoracoscopic; FVC: - 13% open, - 8% thoracoscopic) (p ≤ 0.02). The posterior cases remained stable (2% FEV, p = 0.7; - 0.6% FVC, p = 0.06). A subgroup of 90 patients with 2 year post-operative PFTs demonstrated that changes were progressive between 2 and 5 years post-operatively. The average change in FVC from 2 to 5 years was significantly different between the anterior open (- 9%) and posterior-only (0.7%) groups (p = 0.015). CONCLUSION: In patients who underwent anterior instrumentation, PFTs declined from the pre-operative to the 5 years post-operative time point. There was a progressive decline of 4-10% beyond 2 years post-operatively. Patients who underwent posterior instrumentation remained stable. These slides can be retrieved under Electronic Supplementary Material.

Selective thoracic fusion of a left decompensated main thoracic curve: proceed with caution?

PURPOSE: Previous research has shown that with certain idiopathic scoliosis curve types, performing a selective thoracic fusion (STF) is associated with an increased risk of coronal decompensation post-operatively. The purpose of the current study was to determine the influence of curve correction and fusion level on post-operative balance in STF for adolescent idiopathic scoliosis patients with pre-operative coronal decompensation. METHODS: A multicenter database was queried for subjects with right Lenke 1-4C curves, pre-operative left coronal imbalance, and 2-year follow-up who underwent STF (caudal fusion level of L1 or proximal). Rates of decompensation were compared between groups with different levels of fusion. Thoracic and lumbar curve correction as well as Scoliosis Research Society-22 outcome scores were compared between groups that were post-operatively balanced or persistently decompensated. RESULTS: 121 patients were identified with average thoracic and lumbar curves of 53° and 41°. Mean pre- and post-operative decompensations were 2.4 ± 1.0 and 1.8 ± 1.1 cm, respectively. Eighteen patients were fused short, 62 to, and 41 were fused past the stable vertebra. Ten patients were fused short, 32 to, and 78 were fused past the neutral vertebra. Incidence of post-operative decompensation was 41%. No differences in post-operative decompensation relative to the stable or neutral vertebra were noted (p = 0.66, p = 0.74). Post-operatively, those patients who were balanced had similar thoracic curve correction (58%) to those decompensated (54%, p = 0.11); however, patients balanced post-operatively had greater SLCC (45 vs 40%, p = 0.04). No differences in SRS-22 outcome scores were noted between groups (p > 0.05). CONCLUSIONS: There was a high rate of post-operative decompensation in patients with pre-operative coronal decompensation undergoing STF. Fusion to or past the stable or neutral vertebra did not affect the risk of persistent decompensation. Attempts to improve SLCC could reduce post-operative decompensation.

Intraoperative Traction May Be a Viable Alternative to Anterior Surgery in Cerebral Palsy Scoliosis ≥100 Degrees.

BACKGROUND: For large scoliosis, 2 strategies to maximize correction include intraoperative traction and/or anterior release. It is unclear which patients will benefit the most form either approach. The purpose of our study is to compare the radiographic, perioperative clinical outcomes, and health-related quality of life (HRQoL) outcomes of 2 approaches when used in severe neuromuscular scoliosis in the setting of cerebral palsy (CP). METHODS: In total, 23 patients with minimum 2-year follow-up, major curves ≥100 degrees, and in whom treatment included posterior spinal fusion were evaluated. Eighteen were treated with posterior spinal fusion with intraoperative traction and 5 with anterior/posterior spinal fusion (APSF). The baseline characteristics, perioperative outcomes, and preoperative and 2-year follow-up data for HRQoL and radiographic measures were compared. RESULTS: The groups had similar age, sex, nutritional and seizure status, GMFCS level, and change in CPCHILD scores. The groups had similar curve magnitude (120 vs. 105 degrees, P=0.330) and flexibility (28% vs. 40%, P=0.090), but the APSF group had less pelvic obliquity (POB) (24 vs. 42 degrees, P=0.009). There were similar postoperative major curves (37 vs. 40 degrees, P=0.350), but greater correction in POB (33.5 vs. 14 degrees of correction, P=0.007) in the traction group. The APSF group had longer anesthesia times (669 vs. 415 min, P=0.005), but similar hospital stays, intensive care unit and days intubated, estimated blood loss, cell saver, and red blood cells used. Although the APSF group had twice the rate of complications (22% vs. 40%) during the first 90 days postoperatively, this did not reach statistical significance. CONCLUSIONS: Both intraoperative traction and anterior surgery were used to aid correction in severe CP scoliosis. Anterior surgery did not offer superior correction or better HRQoL, and was associated with increased operative times, whereas intraoperative traction was associated with greater correction of POB. Intraoperative traction may be a viable alternative to an anterior release in severe CP scoliosis. LEVEL OF EVIDENCE: Level II.

Factors affecting the outcome in appearance of AIS surgery in terms of the minimal clinically important difference.

PURPOSE: The minimal clinically important difference (MCID) of the Appearance domain of the SRS-22 questionnaire is an increase ≥1.0 in surgically treated patients with adolescent idiopathic scoliosis (AIS). However, no study has sought to identify the factors associated with an SRS-22 Appearance score increase greater than the MCID at 2 years. METHODS: A retrospective analysis was performed on a prospectively collected multicenter database of 1020 surgically treated AIS patients with a minimum 2-year follow-up. Patients were divided into two cohorts: "I" = Improved after surgery (Δ Appearance ≥1.0) and "NI" = Not improved after surgery (Δ Appearance <1.0). Univariate regression was used to find a significant difference between the cohorts for individual measures. Multivariate logistic regression was used to find continuous predictors. RESULTS: 663 (65%) patients were improved greater than the MCID, and 357 were not improved (35%). The improved cohort trended toward a greater percentage of underweight patients (p = 0.074) with lower preoperative SRS Appearance scores (p < 0.001) and larger preoperative trunk shifts (p = 0.033). Postoperatively, those patients with greater percent correction of thoracic (p = 0.021) and lumbar (p = 0.003) Cobb angles, smaller apical lumbar translation (p = 0.006), and a greater correction in trunk shift (p = 0.003) were most likely to attain the MCID. CONCLUSION: Several factors influence which patients are most likely to attain the MCID following surgery for AIS. Factors such as preoperative appearance scores and body weight are patient specific; other factors such as percent correction of the thoracic and lumbar Cobb angles, trunk shift, and lumbar apical translation may be influenced by the surgeon. LEVEL OF EVIDENCE: II.

Performing a Definitive Fusion in Juvenile CP Patients is a Good Surgical Option.

BACKGROUND: In juveniles with progressive curves, there is debate regarding the use of growth friendly implants versus definitive fusion. This study presents outcomes of juvenile cerebral palsy (CP) scoliosis patients who underwent definitive fusion before age 11. METHODS: A review of a prospective, multicenter registry identified patients 10 years and younger who had a definitive posterior fusion for their CP scoliosis. Preoperative and postoperative demographic and radiographic changes were evaluated with descriptive statistics. Repeated measures analysis of variance were utilized to compare outcome scores. RESULTS: Fourteen children with a mean age of 9.7 years (8.3 to 10.8 y) and a minimum of 2 years follow-up (range 2 to 3 y) were identified. The mean preoperative curve magnitude and pelvic obliquity was 84±25 degrees (range 63 to 144 degrees) and 25±14 degrees, respectively. All patients were skeletally immature with open triradiate cartilage. Three patients had unit rods with wires while the rest incorporated pedicle screws. Immediately postoperation, the average major curve was 25±17 degrees (P≤0.001, 71% correction rate). At most recent follow-up, the average major curve increased to 30±18 degrees (P≤0.001) for a 65% correction rate. Pelvic obliquity improved to 4±4 degrees (84% correction, P≤0.001) immediately postoperation and to 6±5 degrees (P=0.002) at latest follow-up for a 76% correction rate. None of the patients required revision surgery for progression. From pre to most recent follow-up, the CPchild Health outcome scores improved from 47 to 58 (P=0.019). One patient had a deep infection, and 1 patient had a broken rod that did not require any further treatment. CONCLUSIONS: Progressive scoliosis in juvenile CP patients requires the surgeon to balance the need for further growth with the risks of progression or repeated surgical procedures. Our study demonstrates that definitive fusion once the curves approach 90 degrees results in significant radiographic and quality of life improvements, but further follow-up is needed to determine whether those results remain after skeletal maturity. LEVEL OF EVIDENCE: Level IV-therapeutic.

Incidence of and Risk Factors for Loss of 1 Blood Volume During Spinal Fusion Surgery in Patients With Cerebral Palsy.

BACKGROUND: Spinal fusion surgery is associated with greater blood loss in patients with cerebral palsy (CP) than in patients with adolescent idiopathic scoliosis. Risk factors for loss of 1 blood volume (LOBV) in patients with CP have not been well studied. We investigated the incidence of and risk factors for LOBV during spinal fusion surgery in young patients with CP. METHODS: We queried a multicenter registry of CP patients for all patients 21 years or younger who had undergone spinal fusion from 2008 through 2013; 272 patients met these criteria. We analyzed data on patient characteristics, preoperative laboratory values, radiographic measures, and surgical characteristics. For univariate analysis, we used χ tests and logistic regression models. Factors that were significant in the univariate analysis were used to construct a multivariate logistic regression model. Significance was set at P<0.01. RESULTS: Incidence of LOBV was 39.7%. On multivariate analysis, unit rod construct and coronal curve magnitude were significantly associated with LOBV (P<0.01). The multivariate model accounted for 32.2% of variance in LOBV. Compared with patients with pedicle screw-rod constructs, patients with unit rod constructs had 12.6-fold higher odds of LOBV (P<0.01). For each 1-degree increase in coronal curve magnitude, odds of LOBV increased 1.03-fold (P<0.01). CONCLUSIONS: In patients with CP, there is a substantial risk of LOBV during spinal fusion surgery. Use of unit rod constructs and greater preoperative coronal curves were significant risk factors for LOBV during surgery. LEVEL OF EVIDENCE: Level II.

Major perioperative complications after spine surgery in patients with cerebral palsy: assessment of risk factors.

PURPOSE: A prospective, longitudinal cohort was studied to determine the incidence, consequences, and risk factors of major perioperative complications in patients with cerebral palsy (CP) treated with spinal fusion. There is a wide variety of data available on the complications of spine surgery; however, little exists on the perioperative complications in patients with CP. METHODS: A prospective multicenter dataset of consecutive patients with CP treated with spinal fusion was evaluated. All major perioperative complications were identified and stratified into categories: pulmonary, gastrointestinal, other medical, wound infection, neurological, instrumentation related, and unplanned staged surgery. Univariate and multivariate analyses were performed to identify various risk factors for major perioperative complications. RESULTS: 127 patients were identified with a mean age of 14.3 ± 2.6 years. Overall, 39.4% of the patients had a major perioperative complication. Occurrence of a complication [no complication (NC), yes complication (YC)] resulted in significantly increased intensive care unit (ICU) (NC = 3.2 days, YC = 7.8 days, p < 0.05) and hospital stays (NC = 7.7 days, YC = 15.6 days, p < 0.05). Variables associated with greater risk of a complication included: increased estimated blood loss (EBL) (p < 0.001), larger preoperative kyphosis (p = 0.05), staged procedures (p < 0.05), a lack of antifibrinolytic use (p < 0.05), and a trend toward lower body mass index (BMI) (p = 0.08). Multivariate regression analysis revealed an increased EBL as independently associated with a major perioperative complication (p < 0.05). CONCLUSIONS: In this cohort of patients with CP who underwent spinal fusion, 39.4% experienced a major perioperative complication, with pulmonary being the most common. The occurrence of a major perioperative complication lengthened both ICU and hospital stay. Risk factors for major perioperative complications included greater preoperative kyphosis, staged procedures, a lack of antifibrinolytic use, and increased EBL, with the latter being an independent predictor of a major perioperative complication. LEVEL OF EVIDENCE: 2.

Preoperative warming and undesired surgical and anesthesia outcomes in pediatric spinal surgery-a retrospective cohort study.

BACKGROUND: Underbody forced air warming is a method commonly used for intraoperative temperature maintenance in children. We previously reported that preoperative forced air warming of children undergoing spinal surgery substantially reduces the incidence and duration of intraoperative hypothermia (<36°C). OBJECTIVE: The aim of this study was to evaluate the effects of preoperative warming before spinal deformity surgery on surgical site infection rate, length of hospitalization, and bleeding (estimated blood loss and incidence of cell salvaged and/or allogeneic packed red blood cell transfusions). METHODS: Demographic, anesthetic, and surgical data of all patients who underwent spinal deformity surgery between December 2009 and December 2012 were obtained by retrospective chart review. Temperature data were abstracted from an existing repository; the incidence and duration of hypothermic episodes were identified. For each outcome, logistic regression models and propensity score analysis were used to estimate the effect of prewarming, adjusted for potential confounders. The issue of missing data was handled by a multiple imputation method. Data from 334 procedures were used in modeling and propensity score stratification. RESULTS: Adjusted odds ratios for the effects of prewarming were 0.47 (95% CI 0.15-1.49) for surgical site infections; 0.89 (95% CI 0.55-1.41) for cell salvaged blood transfusion; 0.43 (95% CI 0.22-0.83) for allogeneic packed red blood cell transfusion; and 1.24 (95% CI 0.77-1.99) for a length of hospitalization >6 days. Adjusted mean decrease in estimated blood loss for prewarming was 72 (95% CI -29 to 173) ml. CONCLUSION: In this study, prewarming was associated with a reduction in allogeneic packed red blood cell transfusion. However, no causal relationship between prewarming and reduced allogeneic blood transfusion should be assumed. Prewarming was not associated with reductions in estimated blood loss, length of hospitalization, or the incidence of surgical site infection.

BMPER variants associated with a novel, attenuated subtype of diaphanospondylodysostosis.

Diaphanospondylodysostosis (DSD), caused by loss of bone morphogenetic protein-binding endothelial regulator (BMPER), has been considered a lethal skeletal dysplasia characterized by severe deficiency of vertebral body and sacral ossification, reduced rib number and cystic kidneys. In this study, however, we have demonstrated that variants in BMPER may cause a milder disorder, without renal anomalies, that is compatible with long-term survival. Four siblings, three males and one female, presented with severe congenital scoliosis associated with rib and vertebral malformations as well as strikingly delayed ossification of the pedicles. The female was stillborn from an unrelated cause. Stabilization of the scoliosis with expandable titanium rods was successful in the three boys, all of whom have short stature. An autosomal recessive mode of inheritance was hypothesized. Single nucleotide polymorphism microarray analysis was performed for three of the siblings to identify autosomal genes with shared allele patterns, suggesting possible linkage. Exome sequencing of one sibling was then performed. Rare variants were identified in 347 genes with shared alleles. Only one of these genes had bi-allelic variants in a gene strongly expressed in paraxial mesenchyme: BMPER, which is the cause of DSD, an autosomal recessive disorder. The disorder described herein could represent an attenuated form of DSD or could be designated a separate entity such as spondylopedicular dysplasia.

Recurrence of rib prominence following surgery for adolescent idiopathic scoliosis with pedicle screws and direct vertebral body derotation.

PURPOSE: Pedicle screw constructs combined with direct vertebral body derotation (DVBD) provide a powerful corrective force of the rib prominence associated with adolescent idiopathic scoliosis (AIS). We wished to evaluate the incidence and correlative factors associated with recurrence of rib prominence (RRP) developing postoperatively despite adequate initial correction. METHODS: 103 patients with AIS underwent pedicle screw fixation with DVBD without thoracoplasty and had postoperative scoliometer readings at 6, 12, and 24 months. Patients with RRP, defined as a postoperative scoliometer increase ≥5°, were compared to those without recurrence. RESULTS: The mean rib prominence measured 14.0 ± 4.3° preoperatively, with a correction of 50.3 ± 26.7 % at 6 months, 49.0 ± 39.0 % at 1 year, and 49.1 ± 26.7 % at 2 years. RRP was identified in 15.5 % of the patients with a correction of 57.5 ± 25.5 % at 6 months, 47.2 ± 42.5 % at 1 year, and 40.4 ± 21.6 % at 2 years. At 2 years, the RRP group demonstrated a significantly larger major coronal Cobb (p < 0.05) and a trend towards less curve correction (p = 0.09). Patients with open triradiates had a significantly higher rate of RRP compared to those with closed (p = 0.01). Worsening apical vertebral rotation at 2 years post-operation occurred in 43.8 % (7/16) of the patients with RRP. CONCLUSION: RRP after posterior fusion for AIS with all pedicle screw constructs and DVBD occurred in 15.5 % of patients in our study. Patients with open triradiate cartilage had a significantly higher rate of RRP, although most with RRP were skeletally mature. There was a trend towards loss of coronal correction and increased apical vertebral rotation at 2 years in patients with RRP. The potential for RRP after adequate initial correction should be discussed with patients. LEVEL OF EVIDENCE: 2.

Anterior Vertebral Body Tethering: A Review of the Available Evidence.

Idiopathic scoliosis is a complex three-dimensional deformity of the spine with anterior overgrowth (hypokyphosis), coronal curvature, and axial rotation. Scoliosis treatment in the skeletally immature spine is therapeutically challenging because of growth and was commonly limited to observation, bracing treatment, or fusion. Fusion accomplishes powerful deformity correction at the expense of future growth and mobility of the involved segments, increasing the risk of adjacent segment degeneration and intervertebral disk disease later in life. Anterior vertebral body tethering is a motion-preserving technique that exploits the Hueter-Volkmann principle by applying compression at the anterior and convex aspects of the curve to stimulate differential vertebral growth for gradual deformity reduction without fusion. The appropriate timing, curve magnitude, tensioning, growth prediction, indications, and limitations of tethering are being refined as this technique becomes more prevalent. Early outcome studies show that growth modulation with vertebral body tethering is safe, can achieve good results, and preserve motion in select patients.