Cubital Tunnel Syndrome vs. Radial Tunnel Syndrome

If you’re experiencing pain in your elbow or numbness and tingling in the pinky and ring fingers, you may wonder what’s causing it. Different conditions can cause pain in the same area but have other treatment methods. Two conditions affecting the elbow, surrounding arm regions, and even down into the wrist and hand are cubital tunnel syndrome and radial tunnel syndrome.

What’s Cubital Tunnel Syndrome?

Cubital tunnel syndrome occurs if the ulnar nerve is injured. The cubital tunnel runs inside the elbow and consists of bones, ligaments, and muscles. This syndrome causes inflammation, irritation, and swelling.

Concept of injury, pain, or bruise in the elbow area by Marco Verch Professional Photographer is licensed with CC BY 2.0

What Are the Symptoms of Cubital Tunnel Syndrome?

The pain of cubital tunnel syndrome feels like the sensation of hitting the ulnar nerve, commonly known as the “funny bone” in your elbow. The ulnar nerve runs across the elbow, starting on the side of your neck, then travels down your arm, ending in your fingers. For most people with cubital tunnel syndrome, it causes one or more of the following symptoms:

• Pain in your hands.
• Tingling and numbness in your hand, ring finger, or pinky, especially when you bend your elbow.
• Clumsiness and a compromised grip due to the weakness in your hand and arm.
• Throbbing pain located on the inside of your elbow.

Cubital tunnel syndrome symptoms may present similarly to other medical conditions, such as medial epicondylitis (tennis elbow). This is why it’s important to get a specific diagnosis from a doctor or orthopedic surgeon.

How Is Cubital Tunnel Diagnosed?

Your doctor will thoroughly review your medical history and perform a physical exam. They’ll also order a series of diagnostic tests to confirm your diagnosis, which may include the following:

Nerve Conduction Test

A nerve conduction test measures the speed of signals traveling down a nerve to determine if there’s a constriction or compression.

Electromyogram (EMG)

An EMG tests your nerve and muscle function and can evaluate your forearm muscles, which are controlled by the ulnar nerve. If it’s determined that the muscles are acting abnormally, this may show your doctor that you have an issue with your ulnar nerve.

X-ray

X-rays show the elbow bones to determine whether you have bone spurs or arthritis in your elbow.

How Is Cubital Tunnel Syndrome Treated?

The best treatment for cubital tunnel syndrome is ceasing the activity causing or aggravating the problem, such as overusing or bending the elbow. If that’s not possible, or if it doesn’t work for you, you can consider the following treatments:

• Brace: Wear a foam elbow brace or splint at night to reduce elbow movements in your sleep to help reduce irritation.
• Pad: Use an elbow pad to reduce the chronic irritation from leaning your elbow on hard surfaces, such as when typing or using a mouse.
• Medication: Take non-steroidal anti-inflammatory drugs (NSAIDs) such as naproxen or ibuprofen.
• Exercises: Perform nerve gliding exercises.

If none of these treatments work, your doctor may suggest the following:

• Steroid injections.
• Surgery.

These treatments are usually considered only as a last resort to reduce swelling and relieve pain.

What’s Radial Tunnel Syndrome?

Radial tunnel syndrome occurs due to pressure on the radial nerve inside your arm. The radial nerve starts in your neck and runs down the length of your arm. It controls the movement of your triceps muscle, which is located in your upper arm. Pressure on the radial nerve causes pain along the top of your forearm, which runs down into your hand.

In this condition, the radial nerve is also pinched by two muscles in the upper part of the forearm, contributing to the pain in the elbow and forearm. This pain is most likely due to lifting activities and repetitive grasping.

How Do the Radial Tunnel and Cubital Tunnel Syndrome Symptoms Differ?

Dull, aching forearm pain is the primary symptom of radial tunnel syndrome. Piercing or stabbing sensations can also occur in the wrist. The pain’s likely to intensify when the arm or hand is outstretched. These symptoms are unlike those of cubital tunnel syndrome, which causes pain that starts in the inner elbow and wraps around to the outer elbow. In radial tunnel syndrome, some patients experience numbness on the back of their hands and thumb. This differs from cubital tunnel syndrome, with numbness affecting the ring finger, the pinky, or the inside of the hand.

How Is Radial Tunnel Syndrome Diagnosed?

This condition is challenging to diagnose since there aren’t any imaging tests that can detect it. Your doctor may rely on a process of elimination instead, performing the same kinds of tests for cubital tunnel syndrome. These may include X-rays, MRIs, or an electromyography test which can help your doctor rule out other conditions or injuries. Your symptoms may provide the most clues as radial tunnel syndrome displays symptoms that help distinguish it from cubital tunnel syndrome or other conditions, such as tennis elbow.

How Is Radial Tunnel Syndrome Treated?

Your doctor will likely recommend starting with non-surgical methods of treatment to see if they bring relief. Some treatments may include physical therapy, ultrasound massage, immobilizing the wrist with a splint or casting, or NSAIDs. Your doctor may also perform a radial nerve block that uses a local anesthetic injection through the radial tunnel, which may provide partial or complete relief for your symptoms.

If none of these treatments work, your doctor may recommend surgery to relieve your symptoms and pain. Surgery to treat radial tunnel syndrome is designed to alleviate the abnormal pressure on the nerve that passes through the radial tunnel. The nerve may be pinched in multiple spots, so your surgeon will check all areas that may be involved in your particular case.
During the procedure, your surgeon will cut any parts of the radial tunnel causing the pinching. Then they’ll expand the tunnel to relieve the pressure on your radial nerve. This surgery can be performed on an outpatient basis with general or local anesthesia.

Although cubital and radial tunnel syndrome may seem similar at first glance, they have very different characteristics, diagnoses, and treatments. Only an experienced hand and wrist specialist can diagnose and treat either condition. If you’re in the Dallas, Texas, area, the orthopedic surgeons at the Hand & Wrist Institute can give you expert care. Dr. Knight and the Hand & Wrist Institute team provide quality care for a variety of conditions. Contact us at 855-558-4263 or complete our secure online contact form to get started today. To learn more about common hand and wrist conditions, visit our blog to read about causes, symptoms, and treatment options available here at the Hand and Wrist Institute.

Dr. John Knight

Dr. Knight is a renowned hand, wrist and upper extremity surgeon with over 25 years of experience. Dr. Knight is a Board Certified Orthopedic Surgeon and Fellowship trained. Dr Knight has appeared on CNN, The Doctors TV, Good Morning America, The Wall Street Journal, The Washington Post, Forbes, The Huffington Post, Entrepreneur, Oxygen network and more.