Purpose of the study: The natural history of congenital scoliosis or kypho-scoliosis resulting from a hemivertebra is well documented. The spinal deformation generally worsens in children with a free or semi-segmented hemivertebra situated in the thoraco-lumbar, lumbar or lumbosacral region.
Material and methods: From 1982 to 1997, fifteen pediatric patients with 15 hemivertebrae causing progressive scoliosis or kypho-scolisosis underwent hemivertebral resection via a double posterior and anterior approach associated with convex fusion. Mean age at surgery was 4.4 years. The fifteen patients were reviewed at bone maturity (Risser 4 or 5) to assess outcome.
Results: Genitourinary tract anomalies were associated in five of the 15 patients and intrathecal anomalies in two. Mean follow-up was 12.1 years. Segmental scoliosis was 30.2 degrees preoperatively, 12.3 degrees postoperatively and 8.9 degrees at last follow-up. The values for total scoliosis were 30.5 degrees, 12.3 degrees and 12.6 degrees respectively. This was a 70.5% improvement at last follow-up for segmental scoliosis and 58.7% for total scoliosis. The real trunk imbalance improved from 31% preoperatively to 9% at last follow-up. All these differences were significant.
Discussion: The main objective of surgical treatment for congenital scoliosis due to hemivertebra is to prevent the development of severe deformation which would necessitate a dangerous and difficult procedure to achieve correction. Resection of the hemivertebra via a double approach is the ideal method for early correction. The procedure not only corrects the spinal deformation but also prevents later deterioration. Correction should be performed as early as possible. The result is sustained over time if there is no other associated spinal anomaly. The procedure is safe and the technique well controlled in experimented hands. Patients need to wear a corset for only six months after resection of the hemivertebra.