Treatment of idiopathic scoliosis exceeding 100 degrees - comparison of different surgical techniques.

Background: The treatment of scoliosis exceeding 100 degrees remains a challenge. Anterior fusion only may lead to low correction and screw plowing, posterior fusion only may cause the cranckshaft phenomenon in skeletally immature patients. Two-stage surgery is advocated, comprising anterior release and posterior fusion.

Material And Methods: The aim of the paper is to compare treatment outcomes in patients with a >100% primary curve treated between 1984 - 2004 with one of the following techniques: halo-femoral traction with posterior fusion (Group I; n=124 patients), anterior release with halo-femoral traction and posterior fusion (Group II; n=32), single stage anterior release and posterior fusion (Group III; n=20), and posterior fusion only (Group IV; n=19). Correction and loss of correction were assessed radiologically. Additional surgical procedures and the presence of complications were also recorded. The fusion techniques were compared. Mean post-operative follow-up duration was 3.9 years, ranging from 2 to 15.3 years.

Results: Correction was highest in Group II and Group III (52.7% and 51.7%, respectively); vs. Group I and Group IV (45.8% and 38.7%, respectively). The loss of correction at final follow-up was lowest in Group II and Group III (2% and 3.3%), and highest in Group I and Group IV (6.4% and 15.6%, p<0.05). In all groups, the use of derotational instrumentation increased correction (59.7% C-D vs. 37% Wisconsin vs. 24.5% Harrington-Luque) and decreased loss of correction (4% C-D vs. 5% Harrington-Luque vs. 28% Wisconsin). Rates of neurological complications were similar in all groups; no persistent deficits were noted.

Conclusions: Anterior release with halo traction and posterior fusion is the optimal treatment of severe scoliosis. If halo traction is contraindicated, single stage anterior release and posterior fusion should be performed. Contemporary instrumentation techniques result in higher correction rates and better curve stability.