A 36-year-old competitive cyclist presents with numbness affecting the palmar aspect of the fifth digit and weakness when abducting his fingers. Vital signs are normal (BP 118/76, HR 68, RR 14, Temp 98.6°F). Sensation is preserved over the dorsum of the hand. Electromyography shows denervation in intrinsic hand muscles supplied by one nerve. He denies cervical spine pain or upper arm symptoms. Compression of which of the following structures most likely explains his clinical findings?
- A)Ulnar nerve at Guyon canalGABARITO
- B)Anterior interosseous nerve
- C)Median nerve in carpal tunnel
- D)Posterior interosseous nerve
- E)Radial nerve
Explicação
Compression of the ulnar nerve in Guyon canal, often called handlebar palsy, causes weakness of interossei and palmar sensory loss in the medial digits. Dorsal sensation can be spared because the dorsal cutaneous branch arises proximal to the canal. Ver explicação completa e trilha adaptativa →