[The effect of anterior spinal release on severe adolescent idiopathic scoliosis]

To explore the effect of anterior spinal release on severe scoliosis.

Twenty-six cases of severe scoliosis were retrospectively reviewed from January 1998 to December 2001. There were 7 males and 19 females with an average age of 15 years (ranging from 10 to 21 years). Twenty-four cases were classified according to King classification for adolescent idiopathic scoliosis, including King type I 4 cases, type II 9 cases, type III 5 cases, King IV 4 cases, King V 2 cases; another two cases were thoracolumbar curve. The major curves were averaged respectively 89.8 degrees, 66.5 degrees, 67.7 degrees, 61.2 degrees on standing, traction, bending and fulcrum film before operation. The distance of apex vertebrae deviated from sacral midline was 39.7 mm before operation.

Six cases received anterior spinal release with posterior correction by one stage, 20 cases by two stages. The cases with two stage operation increased the spinal flexibility about 17.8 degrees after anterior release. The major curve was 52.6 degrees on average, and the distance of apex vertebrae deviated from sacral midline was 9.9 mm after operation. The major curve was 54.9 degrees on average, loss the correction 6.4% during follow-up. There was no complication related to the operation in this group.

The anterior spinal release alone has little effect on severe scoliosis with flexibility less than 20% preoperation. The curve can be corrected to a great degree by anterior osteotomy for spine.