False aneurysm of the brachial artery complicating closed fracture of the humerus. A case report.

A 66-year-old, obese, mentally retarded man sustained a closed spiral fracture of the humerus accompanied by development of a large false aneurysm arising from a small rent in the distal third of the brachial artery. Because of the patient's body habitus, mental deficiency, and paucity of objective physical findings, the arterial injury was not suspected until expensive pressure necrosis necessitated shoulder disarticulation as a lifesaving measure. Although false aneurysms are known to complicate penetrating trauma and various surgical procedures using metallic implants, the lesion has not been previously reported with closed long bone fractures. The authors wish to alert others to occurrence of the occult arterial injury in association with a relatively common extremity fracture. The need to exercise special awareness and suspicion of subtle injuries in patients whose age, mental status, or associated trauma render communication of symptoms impossible, cannot be overemphasized.