Ulnar neuropathy resulting from diffuse intramuscular hemorrhage: a case report.

The ulnar nerve can be injured in the arm, forearm, and wrist. This report describes a 79-year-old woman who presented to the emergency department with acute lower extremity weakness and vertigo. Her medical history was significant for moderate to severe aortic stenosis, hypertension, and a remote intravascular thrombosis in the right forearm. The patient was diagnosed with a transient ischemic attack and was treated with anticoagulants. Three days after beginning anticoagulation therapy, she developed a diffuse intramuscular hemorrhage in the arm, which compromised predominantly ulnar fibers. The clinical, radiologic, and electrodiagnostic abnormalities are reviewed, and the possible etiologies of ulnar neuropathy are discussed. To our knowledge, this is the first report of ulnar neuropathy secondary to diffuse hemorrhage into the muscles of the arm.