Carpal tunnel syndrome is the most common cause of median nerve lesion. It’s a compression neuropathy due to entrapment of the median nerve within the carpal tunnel at the wrist. Demyelination of the median nerve occurs.
The risk factors are:
- Certain repetitive wrist movements at work
- Sensory symptoms (pain, paraesthesia)
- Middle of the palm
- Palmar aspect of first, second, and third fingers
- Lateral half of the fourth finger
- Motor symptoms (less common)
- Weak pinching
- Weak grip
- Thenar atrophy
Diagnosis and evaluation
ENG can show demyelination (slow conduction), and ultrasound can show enlarged nerve.
Treatment options include splinting, steroid injection, and surgical cutting of the carpal tunnel.
6B. Guillain-Barre syndrome
7B. Secondary headaches