Anterior surgery with short fusion using the Zielke procedure for thoracicscoliosis: Focus on the correction of compensatory curves

Anterior instrumentation is recommended to correct idiopathic thoracolumbar or lumbar scoliosis through short fusion within the major curve. Only a fe w reports exist of anterior surgical correction for thoracic scoliosis. Thi s study assessed the results of Zielke instrumentation for thoracic curve a nd analyzed the three-dimensional correction of deformity, especially corre ction of the uninstrumented compensatory curve. Seventeen patients, who had undergone selective thoracic correction and fusion using the Zielke proced ure to treat thoracic scoliosis, had been followed for at least 3 years. Th ree-dimensional correction was evaluated radiographically. Furthermore, thr ee-dimensional back deformities were evaluated using a topographic body sca nner. Twelve patients with a single thoracic curve and five with a double c urve were all female, with a mean age of 14.6 years. The preoperative main thoracic curve was 54.8 degrees +/- 10.5 degrees (range, 40-78 degrees), an d it was 23.8 degrees +/- 10.5 degrees (range, 7-40 degrees) at the final f ollow-up examination (p < 0.0001). The average correction rate of the main curves was 56.6%. By correcting the thoracic curve, the upper and lower com pensatory curves were corrected spontaneously without surgical instrumentat ion, with average correction rates of 45.1% and 50.2%, respectively. The av erage correction loss of the main curve was 2.3 degrees. The hump angle mea sured using a topographic body scanner decreased from 12.8 degrees +/- 4.5 degrees to 8.4 degrees +/- 4.3 degrees after surgery (p = 0.0001). Of the t hree patients in whom the rod broke up, only one showed a correction loss o f 10 degrees; however, bony fusion was obtained. Anterior short fusion for thoracic scoliosis appears to offer significant correction, stabilization, and spontaneous correction of the compensatory lumbar curve without limitin g lumbar motion.