[The Schwartz-Jampel syndrome (myotonia chondrodystrophica)].

Report on three siblings with typical features of Schwartz-Jampel's syndrome which is transmitted by a rare autosomal recessive gene: odd facies, stiff posture, high pitched voice, myotonic reaction, Perthes-like dysplasia of the femoral head. Biochemical and histological findings are minimal and nonspecific.