Introduction The most common ulnar neuropathies are cubital tunnel syndrome caused by ulnar nerve compression at the elbow ulnar tunnel syndrome caused by ulnar nerve compression at the wrist in Guyon's canal Anatomy The ulnar nerve is a branch of the medial cord of the brachial plexus ulnar sensory function sensory branches dorsal cutaneous branch palmar cutaneous branch superficial terminal branches ulnar nerve innervates forearm flexor carpi ulnaris flexor digitorum profundus III and IV thenar adductor pollicis deep head of flexor pollicis brevis (FPB) fingers dorsal and palmar interossei 3rd and 4th lumbrical (1st and 2nd by median nerve) digiti minimi abductor digiti minimi opponens digiti minimi flexor digiti minimi Ulnar nerve at elbow see medial approach to elbow pierces intramuscular septum at Arcade of Struthers enters cubital tunnel which is formed by roof formed by Osborne's ligament (travels from the medial epicondyle to the olecranon) floor formed by posterior and transverse bands of MCL Ulnar nerve at wrist nerve enters Guyon's canal which is created by floor formed by tranverse carpal ligament, pisohamate ligament, pisometacarpal ligament, and opponens digiti minimi roof formed by volar carpal ligament ulnar wall formed by Pisiform and abductor digiti mini radial wall formed by Hook of hamate Presentation Symptoms same for both cubital and ulnar tunnel syndrome paresthesias over small finger and ulnar half of 4th finger and ulnar dorsum of the hand exacerbating activities include cell phone use (excessive flexion) night symptoms caused by sleeping with arm in flexion trauma traction of the upper extremity, fracture of elbow symptoms can be delayed in tardy ulnar palsy Physical exam deformity claw hand deformity sensory decreased sensation in ulnar 1 1/2 digits motor weakened grasp weak pinch provocative tests for cubital tunnel syndrome Tinnel sign positive over cubital tunnel imaging Radiographs usually normal EMG / NCV helpful to establish the diagnosis Treatment Nonoperative NSAIDS, activity modification, and night time bracing Operative ulnar nerve decompression
QUESTIONS 1 of 2 1 2 Previous Next Sorry, this question is for PEAK Premium Subscribers only Upgrade to PEAK (M2.OR.17.4798) A 27-year-old young man presents to his primary care physician for weakness and tingling in his hand. The patient is an avid bodybuilder and has noticed that his grip strength has gradually worsened in both hands with symptoms worse at the end of a long workout. The patient has a past medical history of anabolic steroid use in high school. His current medications include a multivitamin, fish oil, and whey protein supplements. On physical exam, you note a muscular young man with male pattern hair loss. The patient has a loss of sensation bilaterally over the volar surface of the 4th and 5th digits and over the medial aspect of the volar forearm. The patient has 3/5 grip strength of his left hand and 2/5 grip strength of his right hand. There is also notable weakness of finger adduction and abduction. The rest of the patient's physical exam is within normal limits.Which of the following is the most likely diagnosis? QID: 109237 Type & Select Correct Answer 1 Brachial plexopathy 7% (2/29) 2 Cubital tunnel compression 48% (14/29) 3 Guyon's canal compression 31% (9/29) 4 Carpal tunnel syndrome 7% (2/29) 5 Posterior interosseous nerve compression 3% (1/29) M 5 Question Complexity E Question Importance Select Answer to see Preferred Response SUBMIT RESPONSE 2 Review Tested Concept Review Full Topic