Perforated appendicitis causing thigh emphysema: a case report.

We report a case of thigh emphysema resulting from perforated appendicitis. The patient was an 83-year-old man who had no apparent abdominal signs and was initially misdiagnosed as having psoas abscess. Magnetic resonance imaging of the pelvis revealed appendicitis, and a barium enema showed a leakage of enhanced contrast material from the appendix region down into the thigh. A retroperitoneal perforation of the retrocaecal appendix without peritonitis was diagnosed. The patient underwent an appendectomy and curettage of the retroperitoneal and psoas muscle spaces, as well as the thigh. He recovered gradually, though the abscess had extended into the hip joint and resulted in osteomyelitis, requiring an additional procedure of resection arthroplasty. The patient fully recovered with no signs of infection one year postoperatively.