The rigid spine syndrome--a myopathy of uncertain nosological position.

Four patients meeting the clinical criteria of the rigid spine syndrome are presented; they are one girl with a positive family history and three boys. Clinical and histological findings are discussed in relation to the 14 cases of rigid spine syndrome reported in the literature. The delineations of the syndrome from other benign myopathies with early contractures are discussed suggesting that the rigid spine syndrome probably does not represent a single nosological entity.