Radial Tunnel Syndrome: Causes, Symptoms & Treatment

Written by Stephanie Watson
Medically Reviewed by Nayana Ambardekar, MD on May 27, 2025
8 min read

Radial tunnel syndrome is a painful condition caused by pressure on the radial nerve. This is one of the three main nerves in your arm. It runs from the upper part of your arm down to your hand and provides feeling and movement to your arm and hand.

Just below the elbow, the radial nerve runs through a passageway called the radial tunnel. The tunnel is made from structures such as blood vessels and muscles. Pressure on the radial nerve as it passes through this tunnel causes pain and weakness in the forearm — the part of your arm that extends from your elbow to your wrist.

Radial tunnel syndrome can be uncomfortable. But with rest, medicine, and exercise, the pain and other symptoms should improve within a few weeks.

Radial Tunnel Syndrome Symptoms infographic

Symptoms vary from person to person, but you'll likely feel a dull, aching pain on the back of your forearm. The pain may worsen with activity, especially when you extend your wrist or rotate your forearm so that your palm faces up. Sometimes the pain radiates down the arm to the wrist.

"In severe cases, patients can begin to experience weakness in the muscles of the forearm, as the nerve responsible for radial tunnel syndrome is damaged from chronic or severe compression," says Carl Cirino, MD, a sports medicine surgeon at HSS Orthopedics with Stamford Health in Westport, CT. 

You might feel weakness when you try to extend your fingers or wrist. Eventually, your forearm and wrist can get so weak that it's hard to lift or hold things.

Radial tunnel syndrome vs. tennis elbow

Radial tunnel syndrome and tennis elbow are often confused because they both cause pain and inflammation in the outer part of the elbow. While radial tunnel syndrome is a nerve compression problem, tennis elbow is caused by strain to muscles and tendons on the outside of the elbow. It gets its name from one of the repetitive motions that causes it — swinging a tennis racket. 

"People with tennis elbow usually feel pain right at that bony point on the outside of the elbow, and the pain often flares when they grip something or extend their wrist," says Joseph Buckwalter V, MD, PhD, orthopedic surgeon at University of Iowa Health Care. Pain from radial tunnel syndrome is usually felt lower on the forearm. Also, radial tunnel syndrome causes weakness, while tennis elbow doesn't.

Because it's hard to tell which of these two conditions you have, see a doctor for a diagnosis. Tests such as X-ray, ultrasound, and MRI can show whether it's tennis elbow.

Radial tunnel syndrome vs. PIN syndrome

Both of these conditions are caused by pressure on the radial nerve. The posterior interosseous nerve (PIN) is a branch of the radial nerve that controls movement in the back of your forearm and helps you raise your wrist, fingers, and thumb. 

PIN syndrome happens when an injury or a condition like rheumatoid arthritis puts pressure on the radial nerve. It causes weakness in the wrist and difficulty straightening the wrist and fingers.

Radial tunnel syndrome happens when inflammation inside the radial tunnel puts pressure on the nerve. Any of these activities can cause the condition:

  • Repetitive motions at work, such as typing or turning a wrench
  • Repetitive motions in sports, such as throwing a baseball or football, especially if you don't warm up well first
  • Bending your wrist, gripping things, or rotating your forearm a lot
  • Getting a hard hit to the outside of your elbow

Weightlifters are more likely to get this condition because the repetitive motion of lifting weights puts stress on their radial nerve.

Radial tunnel syndrome can be challenging for doctors to diagnose. "Because the symptoms overlap, radial tunnel syndrome is frequently misdiagnosed as tennis elbow, but a careful exam and awareness of the distinct pain patterns can help tell them apart," Buckwalter says. 

Because no test can specifically diagnose radial tunnel syndrome, your doctor will use your symptoms, health history, and a physical exam to find the cause of your symptoms.

The doctor will look at your arm and apply light pressure to feel for any tender areas. They may ask you to rotate your forearm and hand or flex your wrist to see if you feel any pain. A test called the rule of nine can help confirm the diagnosis. Your doctor will apply pressure to nine different areas on your elbow. Pain in areas 1 and 2 along the side of the elbow is likely due to radial tunnel syndrome. 

These tests help confirm the diagnosis or find another cause for your symptoms:

  • X-rays can rule out other conditions, but they can't diagnose radial tunnel syndrome.
  • MRI may show what's causing pressure on the radial nerve or diagnose tennis elbow. But this test can't diagnose radial tunnel syndrome on its own.
  • Electromyography (EMG) measures electrical activity to see how well your nerves are working. An EMG will usually be normal in radial tunnel syndrome, but it can show if another nerve-related condition is causing your symptoms.

The doctor may give you a shot of the numbing medicine lidocaine, using ultrasound to guide the needle, and see if your symptoms improve. If your pain goes away, it's likely radial tunnel syndrome. Then, the doctor can give you a steroid shot for longer-term relief.

Treatment usually starts with nonsurgical options such as resting your arm and taking medicine. Avoid the repetitive movements that cause radial tunnel syndrome, such as extending your elbow, rotating your forearm, or flexing your wrist. 

These treatments will often get rid of symptoms within six weeks.

Medications

Medicines for radial tunnel syndrome help ease pain and lower inflammation. They include:

  • Nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin, ibuprofen (Advil, Motrin), and naproxen sodium (Aleve)
  • Oral steroids
  • Steroid injections

Physical therapy

A physical therapist can teach you exercises to stretch out the tissue that's putting pressure on your radial nerve. The PT may recommend that you wear a wrist splint to take pressure off the painful nerve. You'll wear the splint for four to six weeks at work or when you do any repetitive motions.

It's important to get the right diagnosis. Sometimes, people who are misdiagnosed with tennis elbow get a counterforce brace or tennis elbow strap that puts pressure on their forearm. "This is exactly the opposite of what we want for a patient with radial tunnel syndrome," says Cirino. This type of brace could worsen your symptoms.

Exercises for radial tunnel syndrome

Your doctor or physical therapist can teach you exercises to stretch and strengthen muscles in your forearm and ease pain. You'll do these exercises for 6-12 weeks.

Wrist extension stretch

  • Hold your arm out straight with your hand out and fingers pointing up.
  • Using your opposite hand, apply gentle pressure to the palm of your outstretched hand and pull it toward you.
  • Hold for 15 seconds.
  • Repeat five times on each arm.

Wrist flexion stretch

  • Hold your arm out straight with your hand out and fingers pointing down.
  • Gently pull your hand toward your body until you feel a stretch on the outside of your forearm.
  • Hold for 15 seconds.
  • Repeat 5 times on each arm.

Radial nerve glide

  • Stand with your arms down at your sides.
  • Drop one shoulder down as you stretch your hand toward the floor.
  • Rotate your arm inward until your thumb points toward your body and flex your wrist so that your palm faces upward.
  • Gently tilt your head away from the arm you're stretching.
  • Slowly lift your arm while keeping your head still.
  • Hold each position for three to five seconds.

You should feel a gentle stretch with these movements, but never pain. If you feel any pain, stop.

Radial tunnel surgery

Surgery is a last resort. Your doctor will consider it only after you've tried treatments like rest and physical therapy for 6 to 12 months and they haven't helped, or if the pain becomes disabling. During the procedure, your surgeon makes one incision in your arm and removes any tissue that's pressing on the radial nerve. 

"The surgery is performed as an outpatient surgery," Cirino says. You'll go home the same day. If you have tennis elbow too, your surgeon can fix both conditions with one procedure.

Recovery from radial tunnel surgery can take 3 to 6 months. Risks include:

  • Nerve damage
  • Pain that doesn't go away
  • Scarring
  • Weakness

If you don't treat radial tunnel syndrome, constant pressure on the nerve could lead to chronic pain and possibly weakness in the wrist or fingers. "This can significantly interfere with daily activities," Buckwalter says.

Radial tunnel syndrome usually isn't preventable, but there are things you can do to lower your risk. Avoid repetitive movements, especially ones where you extend your wrist or rotate your forearm. If you do have to do these movements, take regular breaks, use ergonomic tools, and exercise. "Maintaining flexibility and strength in the forearm muscles can help minimize pressure on the radial nerve and reduce the chances of developing this syndrome," Buckwalter says.

Radial tunnel syndrome is pressure on the radial nerve in the arm that causes pain. It's usually caused by repetitive movements at work or while playing sports. This condition often improves with conservative treatments, such as rest and pain relievers. Surgery is a last resort when symptoms don't improve after 6-12 months.

Is radial nerve damage a disability? 

Radial tunnel syndrome might be considered a disability if you have such severe pain and weakness in your arm that you can't do your job.

Does radial tunnel syndrome go away?

With treatments like rest, exercise, and bracing, radial tunnel syndrome should improve or go away.

Is heat good for radial tunnel syndrome?

Heat or ice can help relieve radial tunnel syndrome symptoms.

What kind of doctor treats radial tunnel syndrome?

A neurologist, sports medicine specialist, or orthopedic surgeon can treat radial tunnel syndrome.