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Purpose: This study sought to analyze factors that predict postoperative shoulder balance based on clinical photography., Methods: Based on inclusion criteria, 132 AIS patients were selected. Age, sex, and BMI of each patient were recorded. The following parameters were recorded from radiographs: clavicle angle, T1 tilt, the upper instrumented vertebra (UIV), lowest instrumented vertebra (LIV) thoracic kyphosis, lumbar modifier, preoperative and postoperative proximal thoracic Cobb angle, preoperative and postoperative main thoracic Cobb angle, and preoperative and postoperative thoracolumbar Cobb angle, if applicable. Two spine surgeons independently assigned the photographs shoulder balance grades based on the WRVAS (1-2 = Acceptable, 3-5 = Unacceptable). Surgeons were blinded as to whether the photographs were taken preoperatively or postoperatively. The shoulders were also graded as right high, left high, or balanced., Results: Of all variables analyzed, only main thoracic Cobb angle correction (MTCAC) showed a statistically significant relationship with postoperative shoulder balance (p = 0.01). Odds of having unacceptable shoulder balance increase by 21% for every 5° increase in MTCAC (Adjusted OR = 1.21, 95% CI 1.015-1.452). The odds of unbalanced shoulders are 4.7 times higher for patients whose MTCAC is 40° or more (p = 0.001). Inter-rater reliability was excellent (k =0 .7). Intra rater reliability was perfect for Surgeon 1 (kappa = 1.0) and showed substantial agreement for Surgeon 2 (kappa = 0.8) CONCLUSIONS: Greater correction of main thoracic Cobb angle predicts unacceptable postoperative shoulder balance with 40° of correction signifying a major dichotomy between acceptable and unacceptable.

Study Design: Retrospective case series., Objective: To quantitatively measure the rate of growth of vertebral bodies in juvenile idiopathic scoliosis (JIS) treated with vertebral body stapling (VBS). VBS has been suggested to be a safe and effective method for modulating the growth of the young scoliotic spine, but few long-term studies have examined its efficacy., Methods: Seven patients with JIS 11 years of age or younger underwent VBS with a minimum 6-year follow-up. Vertebral body height on the unstapled and stapled aspects of the curve was measured from initial and final postoperative radiographs and converted into rate of growth per year. Known staple dimensions were used to standardize the measurements between radiographs. Interstaple distance was measured to demonstrate continued growth of the spine. Adjacent vertebral bodies without instrumentation served as an internal control of growth. Each vertebral body (n = 35) was analyzed as an individual experimental unit., Results: The average rate of growth was 0.86 mm/year (standard deviation [SD] 0.44, 95% confidence interval [CI] 0.71-1.0) per vertebral body on the stapled side and 0.83 mm/year (SD 0.46, 95% CI 0.67-0.98) per vertebral body on the unstapled side of the vertebral body. The adjacent vertebral body segments grew at a rate of 0.91 mm/year (SD 0.42, 95% CI 0.66-1.15) on the stapled side and 0.99 mm/year (SD 0.66, 95% CI 0.61-1.37) on the unstapled side, p < 0.01. The distance between staples increased significantly from 3.0 mm (SD 2.0, 95% CI 2.3-3.6) to 8.4 mm (SD 2.4, 95% CI 7.7-9.3)., Conclusions: Vertebral body growth in the presence of VBS occurred at a similar rate on the stapled and unstapled sides of the curve. The high standard deviation of instrumented segment growth further supports the conclusion that VBS is not a reliable method of growth modulation in the young scoliotic spine., Level of Evidence: IV.

Study Design: Retrospective., Objectives: We aimed to determine if heavier patients with adolescent idiopathic scoliosis (AIS) had more preserved thoracic kyphosis (TK), and as a result, more preserved pulmonary function., Summary of Background Data: Some believe that childhood weight is predictive of adult sagittal plane parameters, with heavier children having greater TK as adults. Generally, thoracic scoliosis is coupled with loss of TK, which is associated with worsening pulmonary function., Methods: A total of 142 patients with AIS and a structural main thoracic curve were analyzed. We excluded patients with structural proximal thoracic curves (Lenke 2 and 4). Standing preoperative radiographs, pulmonary function tests, and preoperative body mass indices (BMIs) were reviewed. The main thoracic Cobb angle, T2-T12 TK, percentage predicted forced vital capacity (FVC) and BMI were recorded. Spearman correlation was determined. Linear regression analysis used FVC as the primary outcome and BMI, TK, and Cobb angle as the independent variables. BMI categories were overweight/obese (BMI ≥25) and normal (BMI <25). Wilcoxon rank-sum tests were performed to detect a difference in TK and BMI between the 2 groups. The Cobb angles between the two groups were analyzed by t tests., Results: Demonstrated correlations included BMI and FVC (0.37, p ≤.01), FVC and TK (0.26, p <.01), BMI and TK (0.23, p = .01), and FVC and Cobb angle (-0.23, p = .01). Linear regression revealed that Cobb angle (p ≤.01), TK (p <.01), and BMI (p <.01) remained statistically significant predictors of FVC. Wilcoxon rank-sum tests revealed a statistically significant difference between TK (p = .03) and FVC (p <.01) in the overweight/obese group and the normal group, with the overweight/obese group having greater values for both TK and FVC. The Cobb angles between the overweight/obese and normal group were not significantly different (p = .72)., Conclusions: Heavier AIS patients have greater values of TK and percentage predicted FVC., Level of Evidence: Level III., (Copyright © 2018 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.)