Cubital Tunnel Syndrome

The ulnar nerve is one of 3 main nerves in the arm, responsible for giving feeling to the pinkie finger and half of the ring finger as well as controlling most of the little muscles in the hand needed for fine movements. It travels down from the neck to the hand and thus has several areas along the way where it can be constricted like beneath the collarbone or at the wrist. The most common location for compression of the ulnar nerve is at the cubital tunnel, a tunnel of tissue beneath a bump of bone on the inner elbow (the medial epicondyle).

The ulnar nerve is especially prone to compression at the elbow because it must navigate a narrow space with less protective soft tissue. Keeping the elbow bent for extended periods of time, repeatedly bending, and leaning on the elbow can result in painful symptoms. Risk factors include previous trauma, especially fractures or dislocations of the elbow, as well as swelling of the elbow joint and cysts near the joint. There can also be anatomical predisposition if the ulnar nerve doesn’t stay in place and snaps over the bony bump when the elbow is moved.

A compressed ulnar nerve can result in the sensation of hands and fingers “falling asleep,” most commonly the ring and little “pinkie” finger. Weakened grip and difficulty with finger coordination (activities like typing or playing an instrument) are common symptoms.

For most cases, nonsurgical options like restricting activities and bracing are sufficient treatment. NSAIDs and nerve gliding exercises may also be recommended. Surgical treatment options include a cubital tunnel release, where the ligament “roof” of the cubital tunnel is divided to allow more space for the ulnar nerve to move through. The nerve can also be moved to a few different places, either on top of the muscle (subcutaneous transposition), within it (intermuscular transposition), or under it (submuscular transposition). Depending on the severity of the compression, irreversible muscle wasting can occur in the hand.