SHORT SEGMENT ANTERIOR CORRCTION OF MODERTAE SINGLE PRIMARY CURVE ADOLESCENT IDIOPATHIC SCOLIOSIS

Introduction Our short segment anterior technique produces similar correction and better functional outcomes for patients with adolescent idiopathic scoliosis by instrumentation of fewer levels than does posterior segmental instrumentation. We present the results of the first consecutive 45 patients operated by the short segment bone-on-bone anterior scoliosis technique, with a mean follow-up of 6 years. Every patient was followed up over 2 years and none was lost to follow-up. Methods The patients (28 with thoracic scoliosis; 17 with thoracolumbar scoliosis) were operated between 1996 and 2004 for single curve idiopathic scoliosis. The mean age was 19 years (range 9–51); 87% of the cohort was female and the mean follow-up was 72 months (range 28–121). We operated on curves less than 75° by the short segment anterior approach with total discectomy, bone-on-bone apposition, and dual-rod instrumentation. We assessed the sagittal and coronal corrections on erect anteroposterior and lateral radiographs done preoperatively, postoperatively, and at final follow-up. Results A mean of five vertebrae (four discs) were instrumented. The mean operative time was 360 min, blood loss was 877mL, and hospital stay was 9·1 days. The preoperative thoracolumbar major curve was 50·5°, and 18·3° at final follow-up (image A, B). The preoperative lower tilt angle was 27·7°, and 8·3° at final follow-up. The main preoperative thoracic curve was 52·5°, and the final postoperative curve measured 27·9° (image C, D). The lower preoperative tilt angle was 20·9°, and 11° at final follow-up. Spontaneous improvement of 37·4% was noted in thoracic compensatory curves and 47·5% in thoracolumbar compensatory curves. The sagittal and coronal balance was restored in all patients. There was no loss of correction in the operated segment. There were no infections, non-unions, or neurological, vascular, pulmonary, or implant-related complications in the entire series. Union occurred in all the patients in 2–4 months. All the patients had an unrestricted lifestyle within 4 months. Conclusions In treatment of single major curves of less than 75° in patients with adolescent idiopathic scoliosis, the short segment approach of straightening the apical five vertebrae while removing the apical four discs produces good clinical and radiological results with no loss of correction at 6 years. Our series was also free of mechanical complications, re-admissions, or “adding-on” as frequently seen in series of similar cases operated with posterior segmental implants. The short fusions, superb functional rehab, and lack of complications make the short segment bone-on-bone surgical reconstruction the optimal reconstructive option for well screened adolescents whose single curves fit the selection criteria well.