Scoliosis secondary to a hemivertebra: Seven patients with gradual improvement without treatment

Study Design: Retrospective case series. Objective: To make clinicians aware of this unusual natural history. Summary of Background Data: Nonprogressive and progressive scolioses due to hemivertebrae have been abundantly documented in the literature. There has been no article describing spontaneous improvement. Two case reports have been described elsewhere in a general article on natural history. Methods: From a previous review of 1250 patients with congenital spine deformity of all types, 7 patients were identified with spontaneous improvement of their scoliosis due to a hemivertebra during growth. Results: The mean curve at start of observation was 31° (range: 24°-43°), and at the end of observation was 19° (range: 10°-30°). Six of the curves were at the thora-columbar region (T11-L2), and the other at T1. The average duration of follow-up was 9 years. Conclusion: Spontaneous curve improvement is rare, but possible. In view of the difficulty of prediction for curves due to a hemivertebra, careful observation with careful curve measurement is recommended. Inappropriate early, aggressive surgery should be avoided.