NEW PROGNOSTIC FACTORS TO PREDICT THE FINAL OUTCOME OF BRACE TREATMENT IN ADOLESCENT IDIOPATHIC SCOLIOSIS

Study Design. Eighty-five patients with adolescent idiopathic scoliosi s treated with Milwaukee or thoracolumbosacral orthoses at The Duchess of Kent Children's Hospital were studied longitudinally at 4-6-month intervals until maturity for spinal curvature and vertebral rotation, or until termination of brace treatment for persons who experienced br ace failure who went on to have surgery.Objectives, To identify radiol ogic features so that it may be possible to predict outcome of brace t reatment early on. Summary of Background Data, The structural curve wi th poor flexibility and large rotational prominence have been found to be associated with poor prognosis for brace treatment. However, early response to bracing I for spinal deformity and its relationship to fi nal outcome of brace treatment in a longitudinal study is not availabl e in the literature. Methods. Vertebral rotation and Cobb angles measu red from anteroposterior radiographs of the spine obtained before brac ing and 1-2 months after bracing were found valuable for prediction. C hanges in postbrace Cobb angle and vertebral rotation were considered as an increase or reduction only when there was an increase or reducti on of minimum 5 degrees or more from their prebrace measurements. Resu lts, Those patients who showed increase in vertebral rotation and/or i n Cobb angle after brace application were shown to have progression of curves leading to brace failure in 93% of patients, and 79% of these required surgery. The patients with no change in both vertebral rotati on and Cobb angle after bracing often experienced brace failure (69%). Two patients (15%) required surgery. The results show that reduction of both Cobb angle and vertebral rotation after application of a brace is a prognostic indicator for a good outcome (97%), and no patients r equired surgery. Most of the patients with lumbar scoliosis (91%) show ed such reductions. Conclusion. The findings show a strong association between changes in vertebral rotation and the Cobb angle after applic ation of a brace and the final outcome. Reduction in both is indicativ e of a good outcome, whereas increase in one or both indicates brace f ailure.