Preliminary results on the surgical treatment of disabling degenerative scoliosis

Abstract

Degenerative lumbar scoliosis (DLS) is an unsolved condition and is becoming more of a problem in a modern community with increasing elderly population. Our objective is to study prospectively the results of corrective and stabilization surgery in DLS utilizing pedicle screw and plate system after wide posterior decompression surgery at Ramathibodi Hospital. From July 1, 1995 to March 31, 1998, 26 patients with DLS who had Cobb angles of equal or more than 10° with intense neurogenic claudication (walking distance <300 m) or severe back pain underwent decompression surgery followed by deformity correction and fusion utilizing the pedicle-screw-plate system. The patients' age was 62.9 ± 9.4 years. The follow-up time was 18.27 ± 6.44 months. The preoperative and postoperative Cobb angles were 19 ± 8° and 9 ± 7° (p<0.001), respectively, and the mean preoperative and postoperative (last follow-up) walking distances were 47.7 ± 68.8 m and 673.2 ± 419.2 m (p<0.001), respectively. The preoperative and the postoperative average visual analog scales were 8.35 ± 1.56 and 2.3 ± 1.89 (p<0.001), respectively. Pseudarthrosis evidenced by plate breakage was found in two patients (9.1%) by one year. The others (89.9%) were proved to be successful fusion by bending films study. Secondary deformity due to junctional problem occurred in two cases (9.1%). To avoid junctional problem, the spinal segments that need fusion and instrumentation should include (i) all the laminectomized segments; (ii) adjacent segments with moderate disc degeneration; and (iii) the whole instrumented unit centers over the mid-sacral line. By utilizing the L5/S1 buttress technique, most of the L5/S1 junctions with moderate stenosis and degeneration could be saved provided that the L5 body stays in a balanced position. © World Scientific Publishing Company.