The daily educational pearl – ulnar nerve injury at wrist level

Ulnar nerve injury

– described more often with injuries around the elbow / lower humerus, however the ulnar nerve can become compressed at the level of the wrist as it enters Guyon’s canal or as the deep branch curves around the hook of the hamate. Common causes are carpal bone fractures, local inflammation, masses (ganglion cysts, lipomas).

In is commonly seen in cyclists – cyclist/handlebar palsy.

The symptoms can be isolated sensory (tingling in the 5th and lateral 4th fingers), motor (rare, resulting in paralysis and wasting of the small muscles of the hand), or both.

If it is due to acute trauma (fracture / open injury), the patient needs urgent Orthopaedics or Plastics review.

If it is a chronic condition, the patient should be advised to wear padded gloves (or pad the handlebars) or change hand position on the handlebars. They should be started on antiinflamatories if there is no contraindication, and referred for outpatient follow-up (either Orthopaedics or Plastic Surgery).