Problems originating at the neck: thoracic outlet syndrome, cervical spine pathology, compression by anterior scalene muscles Problems originating in the chest: compression by pectoralis minor muscles Brachial plexus abnormalities Elbow: fractures, growth plate injuries, cubital tunnel syndrome, flexorpronator aponeurosis, arcade of Struthers[6] Forearm: tight flexor carpi ulnaris muscles[7] Wrist: fractures, ulnar tunnel syndrome, hypothenar hammer syndrome Artery aneurysms or thrombosis Other: Infections, tumors, diabetes, hypothyroidism, rheumatism, and alcoholism