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Epidemiological data for the prevalence of SHS are not available, but less than 100 cases have been reported in the literature.

Other common clinical features of SHS include prominent nasolabial folds, high arched palate, attached earlobes, mild cervical webbing, short stature, severe camptodactyly, ulnar deviation, and vertical talus and/or talipes equinovarus. Typically, the contractures are most severe at birth and non-progressive.

Mutations in either MYH3, TNNI2, or TNNT3 have been found in about 50% of cases. These genes encode proteins of the contractile apparatus of fast twitch skeletal muscle fibers.

The diagnosis of SHS is based on clinical criteria.

Mutation analysis is useful to distinguish SHS from arthrogryposis syndromes with similar features (e.g. distal arthrogryposis 1 and Freeman-Sheldon syndrome; see these terms).

Prenatal diagnosis by ultrasonography is feasible at 18-24 weeks of gestation. If the family history is positive and the mutation is known in the family, prenatal molecular genetic diagnosis is possible.

SHS is inherited in an autosomal dominant pattern but about half the cases are sporadic.

There is no specific therapy for SHS. However, patients benefit from early intervention with occupational and physical therapy, serial casting, and/or surgery.

Life expectancy and cognitive abilities are normal.