Recovery kinetics following spinal deformity correction: a comparison of isolated cervical, thoracolumbar, and combined deformity morphometries.

BACKGROUND CONTEXT: The postoperative recovery patterns of cervical deformity patients, thoracolumbar deformity patients, and patients with combined cervical and thoracolumbar deformities, all relative to one another, is not well understood. Clear objective benchmarks are needed to quantitatively define a "good" versus a "bad" postoperative recovery across multiple follow-up visits, varying deformity types, and guide expectations. PURPOSE: To objectively define and compare the complete 2-year postoperative recovery process among operative cervical only, thoracolumbar only, and combined deformity patients using area-under-the-curve (AUC) methodology. STUDY DESIGN/SETTING: Retrospective review of 2 prospective, multicenter adult cervical and spinal deformity databases. PATIENT SAMPLE: One hundred seventy spinal deformity patients. OUTCOME MEASURES: Common health-related quality of life (HRQOL) assessments across both databases included the EuroQol 5-Dimension Questionnaire and Numeric Rating Scale (NRS) back pain assessment. In order to compare disability improvements, the Neck Disability Index (NDI) and the Oswestry Disability Index (ODI) were merged into one outcome variable, the ODI-NDI. Both assessments are gauged on the same scale, with minimal question deviation. Sagittal Radiographic Alignment was also assessed at pre- and all postoperative time points. METHODS: Operative deformity patients >18 years old with baseline (BL) to 2-year HRQOLs were included. Patients were stratified by cervical only (C), thoracolumbar only (T), and combined deformities (CT). HRQOL and radiographic outcomes were compared within and between deformity groups. AUC normalization generated normalized HRQOL scores at BL and all follow-up intervals (6 weeks, 3 months, 1 year, and 2 year). Normalized scores were plotted against follow-up time interval. AUC was calculated for each follow-up interval, and total area was divided by cumulative follow-up length, determining overall, time-adjusted HRQOL recovery (Integrated Health State, IHS). Multiple linear regression models determined significant predictors of HRQOL discrepancies among deformity groups. RESULTS: One hundred seventy patients were included (27 C, 27 T, and 116 CT). Age, BMI, sex, smoking status, osteoporosis, depression, and BL HRQOL scores were similar among groups (p >. 05). T and CT patients had higher comorbidity severities (CCI: C 0.696, T 1.815, CT 1.699, p = .020). Posterior surgical approaches were most common (62.9%) followed by combined (28.8%) and anterior (6.5%). Standard HRQOL analysis found no significant differences among groups until 1-year follow-up, where C patients exhibited comparatively greater NRS back pain (4.88 vs. 3.65 vs. 3.28, p = .028). NRS Back pain differences between groups subsided by 2-years (p>.05). Despite C patients exhibiting significantly faster ODI-NDI minimal clinically important difference (MCID) achievement (33.3% vs. 0% vs. 23.0%, p < .001), all deformity groups exhibited similar ODI-NDI MCID achievement by 2-years (51.9% vs. 59.3% vs. 62.9%, p = 0.563). After HRQOL normalization, similar results were observed relative to the standard analysis (1-year NRS Back: C 1.17 vs. T 0.50 vs. CT 0.51, p < .001; 2-year NRS Back: 1.20 vs. 0.51 vs. 0.69, p = .060). C patients exhibited a worse NRS back normalized IHS (C 1.18 vs. T 0.58 vs. CT 0.63, p = .004), indicating C patients were in a greater state of postoperative back pain for a longer amount of time. Linear regression models determined postoperative distal junctional kyphosis (adjusted beta: 0.207, p = .039) and osteoporosis (adjusted beta: 0.269, p = .007) as the strongest predictors of a poor NRS back IHS (model summary: R2 = 0.177, p = .039). CONCLUSIONS: Despite C patients exhibiting a quicker rate of MCID disability (ODI-NDI) improvement, they exhibited a poorer overall recovery of back pain with worse NRS back scores compared with BL status and other deformity groups. Postoperative distal junctional kyphosis and osteoporosis were identified as primary drivers of a poor postoperative NRS back IHS. Utilization of the IHS, a single number adjusting for all postoperative HRQOL visits, in conjunction with predictive modelling may pose as an improved method of gauging the effect of surgical details and complications on a patient's entire recovery process.

Scheuermann's juvenile kyphosis.

OBJECTIVE: Two cases are discussed to illustrate two different presentations, progressions and treatments of Scheuermann's juvenile kyphosis. CLINICAL FEATURES: In one case, a 13-yr-old boy suffered from a 2-yr history of lower back pain. Radiographs demonstrated irregularity of the upper lumbar vertebral endplates, associated with Schmorl's nodes. The second case is one of a 14-yr-old boy who was seen in an orthopedic outpatient clinic. Radiographs revealed wedging of the anterior border of T6, T7, and T8 vertebrae with a thoracic spine kyphotic deformity measuring 72 degrees. INTERVENTION AND OUTCOME: The first case was treated conservatively. The patient maintained his improvement at 6 month follow-up. The second case was initially treated with a brace that the patient did not wear regularly as directed. The kyphotic deformity progressed from 72 degrees to 92 degrees. An operation was performed to reduce the kyphotic curve and prevent further progression. On review 6 yr later, the patient was well without back pain or other complications. The kyphotic curve measured 65 degrees. CONCLUSION: Scheuermann's juvenile kyphosis is a common spinal deformity in the adolescent. A radiographic appearance of wedging of the anterior portion of the vertebral bodies with marked kyphotic deformity suggests the diagnosis of classical Scheuermann's disease. However, the lumbar type of Scheuermann's disease should be considered in young patient with radiographic evidence of irregular vertebral endplates, Schmorl's nodes and a decreased disc space without wedging. Nevertheless, significant progression of the curve in both the typical and atypical types of Scheuermann's disease is rare, but can occur. An algorithm is presented to facilitate decision making in the management of Scheuermann's juvenile kyphosis.