Ulnar Nerve Compression at the Wrist
Definition and Diagnosis
Compression of the ulnar nerve in Guyon's tunnel at the wrist. Compression can be from repetitive pressure or trauma (e.g., factory workers and cyclists), or from cysts, bone spurs, and small aneurysms. Patients report hand weakness and tingling in the small and ring fingers. Tapping at the wrist may cause electrical shocks to enter the small finger. The ulnar nerve is more frequently compressed at the elbow, therefore it is important to exclude compression in this region before treatment at the wrist recommended. Electrical test help localize the compression to the wrist. MRI is often ordered to exclude a mass compressing the nerve.
Any activity that worsens or causes symptoms should be stopped. A wrist splint and the avoidance of pressure on the palm helps the nerve recover over time. If there are no cysts, bone spurs, or aneurysms compressing the nerve, then surgery is rarely indicated, however in some refractory cases it is performed. Surgery may be an option if there is a mass lesion, the patient requires simultaneous carpal tunnel release, or if the patient is recovering from a proximal ulnar nerve injury (by decompressing this nerve also at the wrist, recovery after a more proximal ulnar nerve injury is perhaps optimized).