Ulnar Nerve Entrapment/Cubital Tunnel Syndrome
Ulnar nerve entrapment occurs when the ulnar nerve in the arm becomes compressed or irritated.
The ulnar nerve is one of the three main nerves in your arm. It travels from your neck down into your hand and can be constricted in several places along the way, such as beneath the collarbone or at the wrist. The most common place for compression of the nerve is behind the inside part of the elbow. Ulnar nerve compression at the elbow is called “cubital tunnel syndrome”.
What are the symptoms?
Cubital tunnel syndrome can cause an aching pain on the inside of the elbow. Most of the symptoms, however, occur in your hand.
Numbness and tingling in the ring finger and little finger are common symptoms of ulnar nerve entrapment. Often, these symptoms come and go. They happen more often when the elbow is bent, such as when driving or holding the phone. Some people wake up at night because their fingers are numb.
The feeling of “falling asleep” in the ring finger and little finger, especially when your elbow is bent. In some cases, it may be harder to move your fingers in and out or to manipulate objects.
Weakening of the grip and difficulty with finger coordination (such as typing or playing an instrument) may occur. These symptoms are usually seen in more severe cases of nerve compression.
If the nerve is very compressed or has been compressed for a long time, muscle wasting in the hand can occur. Once this happens, muscle wasting cannot be reversed. For this reason, it is important to see your doctor if symptoms are severe or if they are less severe or if they are less severe but have been present for more than 6 weeks.
How is the diagnosis made?
Your doctor will discuss your medical history and general health. After discussing your symptoms and medical history, your doctor will examine your arm and hand to determine which nerve is compressed and where it is compressed. Some of the physical examination tests your doctor may do include:
Tap over the nerve at the funny bone. If the nerve is irritated, this can cause a shock into the little finger and ring finger, although this can happen when the nerve is normal as well.
Check whether the ulnar nerve slides out of normal position when you bend your elbow.
Move your neck, shoulder, elbow and wrist to see if different positions cause symptoms.
Check for feeling and strength in your hand and fingers.
Nerve conduction studies can determine how well the nerve is working and help identify where it is being compressed. Nerves are like “electrical cables” that travel through your body carrying messages between your brain and muscles. When a nerve is not working well, it takes too long for it to conduct.
During a nerve conduction test, the nerve is stimulated in one place and the time it takes for there to be a response is measured. Several places along the nerve will be tested and the area where the response takes too long is likely to be the place where the nerve is compressed.
Nerve conduction studies can also determine whether the compression is also causing muscle damage. During the test small needles are put into some of the muscles that the ulnar nerve controls. Muscle damage is a sign of more severe nerve compression.
What is the initial treatment?
Unless your nerve compression has caused a lot of muscle wasting, your doctor will most likely first recommend non-surgical treatment.
If your symptoms have just started, your doctor may recommend an anti-inflammatory medicine such as Ibuprofen to help reduce swelling around the nerve.
Although steroids, such as Cortisone, are very effective anti-inflammatory medicines, steroid injections are generally not used because there is a risk of damage to the nerve.
Your doctor may prescribe a padded brace or splint to wear at night to keep your elbow in a straight position.
If the initial treatment does not work, what is next?
Your doctor may recommend surgery to take pressure off of the nerve if:
- Non-surgical methods have not improved your condition
- The ulnar nerve is very compressed
- Nerve compression has caused muscle weakness or damage
There are a few surgical procedures that will relieve pressure on the ulnar nerve at the elbow. Your orthopaedic surgeon will talk with you about the option that would be best for you.
These procedures are most often carried out on a day case basis, but some patients may require an overnight stay at the hospital