Fibrous contracture of muscles following intramuscular injections in adults.

Periarticular fibrous muscle contractures in adults from repeated injections in the same site is predictable. The causes of joint contracture in children are many and complex, but in adults it seems certain that this phenomenon is the result of repeated injections of analgesics or other agents into 1 muscle area. Any drug if repeatedly injected locally may cause fibrosis of the muscle and subsequent joint contracture. Five cases of bilateral abduction contracture of the shoulder in adults including the first case of bilateral abduction contractures of shoulder and hip plus bilateral flexion contracture of elbow and extension contracture of a knee are reported. No underlying disease which might predispose to this fibrosis of muscles was noted. The frequency and period of injections were variable over several years. In all patients the interference in activtities of daily living were serious, but the deformities were corrected by release of the fibrous band with relief of discomfort and restoration of joint motion without recurrence. Noting the potential complication of repeated intramuscular injections in one area, this practice should be avoided whenever possible in adults, as well as in children.