Ulnar neuropathy (also known as 'cubital tunnel syndrome', or 'ulnar nerve entrapment') is similar to carpal tunnel syndrome in that it is caused by pressure on a nerve in the arm. The affected nerve is the ulnar nerve, which supplies sensation from the little finger and a section of the ring finger and allows fine motor movement in the hand. The cubital tunnel is a tunnel of tissue at the elbow, and the ulnar nerve travels through this quite close to the skin. When you hit your elbow 'funny bone', the sensation is caused by hitting the ulnar nerve. The nerve can become compressed in the cubital tunnel, or - less commonly - at the collarbone or the wrist.
The most common symptoms of ulnar neuropathy are tingling and numbness in the fingers connected to the ulnar nerve, a weaker hand grip and difficulties with fine motor activities, such as typing or playing a musical instrument. If the condition has been present for a long time, muscles in the hand may waste - this is not reversible.
Any repetitive activity, even consistently sleeping with bent elbows, can cause the condition. Some other factors put you at greater risk of the condition. These include…
- Previous fractures at/near the elbow.
- Previous elbow dislocation.
- Bone spurs.
- Arthritis of the elbow.
- Cysts near elbow joint.
Tests / Diagnosis
The first assessment is a review of symptoms and medical history and a test of feeling and strength in the hands and fingers. The specialist may 'tap' the elbow to test reaction. The initial physical examination is generally followed by x-ray and a nerve conduction test. Symptoms of ulnar neuropathy can overlap with problems in the neck with nerve compression, and an MRI (magnetic resonance imaging) may also be performed to exclude other diagnoses.
Ulnar Neuropathy can be treated with:
- Addressing the underlying cause for ulnar neuropathy, such as avoiding overuse and bending at the elbow. Splints may sometimes be beneficial to avoid elbow bending.
- Depending on where the ulnar is compressed, surgery usually involves an incision behind the elbow to divide the fibrous band that is thickened within the cubital tunnel and causing compression of the ulnar nerve. Once the ulnar nerve is freed, the symptoms of ulnar neuropathy may be sometimes reversible.
- On rare occasions, transposition of the ulnar nerve is performed where the nerve is moved from behind to in front of the elbow to improve the course of the nerve. This is performed if there is ‘subluxation’ of the nerve where the nerve is migrating from the back to the front of the elbow joint, or vice versa.