TECHNIQUE OF ANTERIOR VERTEBRAL OSTEOTOMY DESIGNED TO PRESERVE LUMBAR MOTION AND CORRECT IDIOPATHIC LUMBAR SCOLIOSIS

TECHNIQUE OF ANTERIOR VERTEBRAL OSTEOTOMY DESIGNED TO PRESERVE LUMBAR MOTION AND CORRECT IDIOPATHIC LUMBAR SCOLIOSIS William P Didelot, MD, Thomas F. Kling, Jr., MD; and Richard E. Lindseth, MD; Indiana University, Indianapolis, Indiana USA Current surgical techniques to correct lumbar scoliosis has the disadvantage of fusing the spine and thereby limiting its motion. While it is not clear what problems (in addition to lost motion) will arise long after spine fusion, problems related to fusion can be avoided if the deformity is corrected without fusing the spine. A technique of a U–shaped, closing wedge, anterior vertebral osteotomy of 3 to 4 apical vertebrae was developed. Between 1992 and 1996, we corrected 17 adolescent lumbar scoliosis using this technique. Average age was 13.3 years (12–16 yrs.) and average follow up was 4 years (minimum 2 yrs.). Five patients had 4 level and 12 patients had 3 level osteotomies between T12 and L3. Four level curves averaged 58º (45– 65º) pre–op and were corrected to 24º (20–30º) or 8.7º per osteotomy at follow up. Three level curves average 52º (40–66º) pre–op and were corrected to 27º (12–46º) or 8.1º per osteotomy at follow up. The osteotomized vertebrae were secured with an absorbable Vicryl suture and an ambulatory cast for 4 weeks. No discs were invaded and no permanent instrumentation was used. All osteotomies healed and maintained spine balance. Slight kyphosis occurred over the osteotomized segments, but overall sagittal alignment was maintained. Range of motion of the osteotomized vertebrae measured 29º pre–op and 30º one year after surgery. Complications included: loss of correction in 2 patients (1 immature pt < Risser 3 and a sharp, unbalanced, 3 segment curve); foot drop in 1 pt.; and paresthesias in 2 pts. – all completely recovered. We conclude that correction of lumbar scoliosis without fusion and instrumentation is technically demanding but feasible; it should be done after Risser 3, and will maintain motion, correction, and alignment of the spine in this preliminary study.