Preoperative SRS pain score is the primary predictor of postoperative pain after surgery for adolescent idiopathic scoliosis: an observational retrospective study of pain outcomes from a registry of 1744 patients with a mean follow-up of 3.4 years

Traditionally, adolescent idiopathic scoliosis (AIS) has not been associated with back pain, but the increasing literature has linked varying factors between pain and AIS and suggested that it is likely underreported. Our objective was to investigate factors associated with post-op pain in AIS. A prospectively collected multicenter registry was retrospectively queried. Pediatric patients with AIS having undergone a fusion with at least 2 years of follow-up were divided into two groups: (1) patients with a postoperative SRS pain score ≤ 3 or patients having a reported complication specifically of pain, and (2) patients with no pain. Patients with other complications associated with pain were excluded. Of 1744 patients, 215 (12%) experienced back pain after postoperative recovery. A total of 1529 patients (88%) had no complaints of pain, and 171 patients (10%) had pain as a complication, with 44 (2%) having an SRS pain score ≤ 3. The mean time from date of surgery to the first complaint of back pain was 25.6 ± 21.6 months. In multivariate analysis, curve type (16% of Lenke 1 and 2 curves vs. 10% of Lenke 5 and 6, p = 0.002) and a low preoperative SRS pain score (no pain 4.15 ± 0.67 vs. pain 3.75 ± 0.79, p < 0.001) were significant. When comparing T2–4 as the upper instrumented vertebrae in a subgroup of Lenke 1 and 2 curves, 9% of patients had pain when fused to T2, 13% when fused to T3, and 18% when fused to T4 (p = 0.002). 12% of all AIS patients who underwent fusion had back pain after postoperative recovery. The most consistent predictive factor of increased postoperative pain across all curve types was a low preoperative SRS pain score. These slides can be retrieved under Electronic Supplementary Material.     

A method for assessing axial vertebral rotation based on differential rod curvature on the lateral radiograph

STUDY DESIGN.: Bench-top and retrospective radiographical analyses to determine apical vertebral rotation based on differential rod curvature on the postoperative lateral radiograph. OBJECTIVE.: To develop a clinically relevant methodology for measuring apical vertebral rotation on postoperative lateral radiographs in patients with adolescent idiopathic scoliosis, based on the distance between the spinal rods. SUMMARY OF BACKGROUND DATA.: Traditional methods of analyzing vertebral rotation on plain radiographs are limited in the postoperative spine with segmental instrumentation. A previous methodology based on pedicle screw tip to rod distances on the posteroanterior radiograph is effective but limited by surgical technique and patient positioning relative to the x-ray beam. METHODS.: The trigonometric relationship between the inter-rod distances on lateral radiographs was defined and validated on a biomechanical model, with apical rotation varying from 0° to 20°. The ability to correct for malposition on the lateral radiograph was tested on 11 postoperative radiographs and correlated against corresponding postoperative computed tomographic scans. RESULTS.: The bench-top model had a strong correlation between actual apical rotation and calculated rotation for the full range of image rotations (intraclass correlation coefficient, 0.99). For the 11 clinical cases, comparisons of apical rotation measured on computed tomographic scans were highly correlated to the proposed lateral radiograph calculations (r = 0.84). CONCLUSION.: A technique for measuring apical vertebral rotation based on the inter-rod distance on the lateral and posteroanterior radiographs was developed and validated. This technique is resilient to rotation of the patient within the x-ray machine and can complement measurement of rotation on postoperative posteroanterior radiographs.     

Classification of proximal tibial fractures in children

Purpose  To develop a classification system for all proximal tibial fractures in children that accounts for force of injury and fracture patterns. Methods  At our institution, 135 pediatric proximal tibia fractures were treated from 1997 to 2005. Fractures were classified into four groups according to the direction of force of injury: valgus, varus, extension, and flexion–avulsion. Each group was subdivided into metaphyseal and physeal type by fracture location and Salter–Harris classification. Also included were tibial tuberosity and tibial spine fractures. Results  Of the 135 fractures, 30 (22.2%) were classified as flexion group, 60 (44.4%) extension group, 28 (20.8%) valgus group, and 17 (12.6%) varus group. The most common type was extension-epiphyseal-intra-articular-tibial spine in 52 fractures (38.5%). This study shows that proximal tibial fractures are age-dependent in relation to: mechanism, location, and Salter–Harris type. In prepubescent children (ages 4–9 years), varus and valgus forces were the predominate mechanism of fracture creation. During the years nearing adolescence (around ages 10–12 years), a fracture mechanism involving extension forces predominated. With pubescence (after age 13 years), the flexion–avulsion pattern is most commonly seen. Furthermore, metaphyseal fractures predominated in the youngest population (ages 3–6 years), with tibial spine fractures occurring at age 10, Salter–Harris type I and II fractures at age 12, and Salter–Harris type III and IV physeal injuries occurring around age 14 years. Conclusion  We propose a new classification scheme that reflects both the direction of force and fracture pattern that appears to be age-dependent. A better understanding of injury patterns based on the age of the child, in conjunction with appropriate pre-operative imaging studies, such as computer-aided tomography, will facilitate the operative treatment of these often complex fractures.     

Early experience with medial femoral tension band plating in idiopathic genu valgum

Purpose  

For correction of angular deformity, tension band plating has been proposed as a safe and minimally invasive technique. The purpose of this study was to assess the experiences and report the rate of correction obtained with this procedure in patients with idiopathic genu valgum.