Muscle ultrasonography in arthrogryposis. Comparison with clinical, neuromyographic and histologic findings in 41 cases.

We studied the ultrasonographic appearance of muscles in 41 patients with arthrogryposis multiplex congenita (AMC). The observations were compared to the findings in clinical testing, electroneuromyography, and histological examination. The strength of the muscles in AMC-patients did not always correspond to the ultrasonographic morphology of the muscles. In extension contractures of the elbow and in equinovarus adductus deformities of the foot there was a distribution of pathological changes in the muscles corresponding to the primary deformity. The sound transfer through the muscles was decreased, notably in the neurogenic form of AMC. Ultrasonography is an important complement to the clinical examination and it should always be done prior to surgery and muscle biopsy.