Cubital tunnel syndrome, also called ulnar nerve entrapment is a condition caused by compression of the ulnar nerve in an area of the elbow called the cubital tunnel. The ulnar nerve travels down the back of the elbow behind the bony bump called the medial epicondyle and through a passageway called the cubital tunnel. The cubital tunnel is a narrow passageway on the inside of the elbow formed by bone, muscle, and ligaments with the ulnar nerve passing through its centre. The roof of the cubital tunnel is covered with soft tissue called fascia. When the elbow is bent, the ulnar nerve can stretch and catch on the bony bump. When the ulnar nerve is compressed or entrapped, the nerve can tear and become inflamed leading to various symptoms.
Signs and Symptoms
Signs and symptoms of cubital tunnel syndrome usually occur gradually, progressing to the point where the patient seeks medical attention. Left untreated, cubital tunnel syndrome can lead to permanent nerve damage in the hand. Commonly reported symptoms associated with cubital tunnel syndrome include intermittent numbness, tingling, and pain to the little finger, ring finger, and the inside of the hand. These symptoms occur more frequently at night, and with elbow bending or prolonged resting on the elbow.
Causes
Injury to the elbow such as fractures, dislocations, or a direct blow can cause tissue swelling which can compress the ulnar nerve within the cubital tunnel. Individuals who perform repetitive elbow flexion movements at work or play are believed to be at high risk for developing cubital tunnel syndrome. Repeatedly bending and straightening the elbow can irritate and inflame the ulnar nerve. Leaning on the elbow for extended periods of time such as when working at a desk can also cause ulnar nerve irritation. Bone spurs, ganglion cysts, or tumours can form in the cubital tunnel leading to pressure and irritation of the ulnar nerve.
Diagnosis
Early diagnosis of Cubital Tunnel Syndrome is critical in avoiding permanent nerve damage.
Your physician will perform the following:
- Medical History
- Physical Examination
- X-rays: A form of electromagnetic radiation that is used to take pictures of bones. Although x-rays do not show nerves and soft structures in the body, your doctor may order this test to look for bone spurs, arthritis, or other bony areas that could be compressing the ulnar nerve.
- Electrodiagnostic Tests: These tests are done to assess the speed and degree of electrical activity in the muscles and nerves. Examples include electromyography and nerve conduction studies. These tests can assist your doctor in determining how well the nerve is functioning and locate areas of muscle wasting and nerve compression.
Conservative Treatment Options
Your physician will recommend conservative treatment options initially to treat the cubital tunnel syndrome symptoms unless muscle wasting or nerve damage is present. Conservative treatment options may include wearing a brace or splint at night while sleeping to keep the elbow in a straight position. You can also wrap the arm loosely with a towel and apply tape to hold in place.
Surgery
If conservative treatment options fail to resolve the condition or if muscle wasting or severe nerve compression is present, your surgeon may recommend you undergo a surgical procedure to treat Cubital Tunnel Syndrome.
Different surgeries are performed to treat your condition.
- Medial Epicondylectomy: This surgery involves removing the medial epicondyle, the bony bump on the inside of the elbow, enabling the ulnar nerve to glide smoothly when the elbow is flexed and straightened
- Ulnar Nerve Transposition: This surgery involves creating a new tunnel in front of the medial epicondyle and transposing (moving) the ulnar nerve to the new tunnel
Your surgeon will decide which surgery would be best for you depending on your conditions.