Diagnosing Ulnar Nerve Compression

To determine if you have ulnar nerve compression, your doctor asks about your symptoms, takes a medical history, and performs a complete examination of your arm, elbow, and hand. Your doctor may also test your arm for strength, sensation, and signs of nerve irritation or damage.

The results of these diagnostic tests help NYU Langone doctors to design an appropriate course of treatment. In addition to a physical exam, other tests may be performed.

X-ray

If you have limited elbow motion, an X-ray may be used to exclude other causes of elbow pain, such as arthritis, recent trauma, or past injuries.

MRI Scan

Your doctor may order an MRI to better view the ulnar nerve. MRI uses magnetic waves and radio waves to create two- or three-dimensional pictures of the inside of the body.

Ultrasound

Your doctor may use an ultrasound to evaluate the ulnar nerve and the soft tissue of the cubital tunnel, which allows the ulnar nerve to travel behind the elbow. During an ultrasound scan, high-frequency sound waves bounce off parts of the body and capture the returning “echoes” as images.

Electromyogram

Electrical testing of ulnar nerve function often helps confirm a diagnosis and can indicate which treatment is best for you. An electromyogram evaluates how the nerves and muscles work together by measuring the electrical impulse along nerves, nerve roots, and muscle tissue. A technician inserts a tiny needle electrode through the skin and into a muscle in the arm. The electrode then measures the amount of electricity generated by muscle cells when they are activated by nearby nerves.

Nerve Conduction Study

If your little finger and part of your ring finger feel numb or tingly, your doctor may order a nerve conduction study, which can determine if there is any nerve damage.

During a nerve conduction test, the nerve is stimulated, and the time it takes to respond is measured. Several places along the nerve are tested, and the area where the response takes too long is likely to be the place where the nerve is compressed. The presence of ulnar nerve compression can be indicated by slower electrical responses at the cubital tunnel or other parts of the arm.

Both nerve conduction studies and electromyography are used to help detect the presence, location, and extent of nerve compression.