Cubital Tunnel Syndrome Info
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Video transcript
Cubital tunnel syndrome happens when the ulnar nerve is squeezed where it passes behind the bony bump on the inside of the elbow, the spot you know as the funny bone. It causes pins and needles, and numbness, in the little and ring fingers. Symptoms are often worse when the elbow is bent for long periods, like holding a phone, or sleeping with the arm curled up. Over time the hand can become weaker and clumsier with fine tasks, like doing up buttons or handling coins. In long-standing cases the small muscles of the hand can visibly waste. Milder cases often settle without surgery. The first step is avoiding long periods with the elbow fully bent, and adjusting how you sit, work, and sleep. A night splint that holds the elbow straighter while you sleep can make a real difference, and is usually trialled for a few months. Nerve tests help confirm the diagnosis, and show how the nerve is conducting. When the numbness becomes constant, the hand is weakening, or the nerve tests show significant slowing, surgery is usually the better path, because established muscle wasting recovers slowly, and sometimes incompletely. The operation is a cubital tunnel release, done as day surgery under a regional or general anaesthetic. Through an incision on the inside of the elbow, the tight roof of the tunnel is divided, releasing the nerve along its course. If the nerve flicks out of its groove when the elbow bends, it is moved to a new position at the front of the elbow, which is called a transposition. The operation takes around thirty to forty five minutes. The wound is closed with dissolving stitches and covered with a soft dressing. There is no period of immobilisation, and you can move the elbow freely from day one. The dressing comes off at around one week, and light desk and household tasks resume in the first week. Lifting, pushing, and gripping are built back up over four to six weeks. The pins and needles often start improving within days, while weakness and wasting recover more slowly, over months, and may not return all the way to normal in long-standing cases. Most people are back to full activity by six to eight weeks.
Cubital tunnel syndrome causes ulnar nerve compression at the elbow — symptoms, diagnosis, and treatment options.
What you're feeling
You might notice aching pain in your elbow or the top part of your forearm, though pain is not the most common symptom. More often, you will feel worsening numbness in your hand and fingers on the pinky side. This numbness often feels like a tingling sensation that gets worse when you keep your elbow bent for a long time. You may find that symptoms flare up at night or when you wake up in the morning.
Daily tasks can become difficult as the condition progresses. You might struggle with gripping objects or feel your hand is weaker than usual. In more advanced cases, the small muscles in your hand can shrink, causing your fingers to look clawed. You may find it hard to reach behind your back to fasten a bra or tuck in a shirt. Men are more likely to notice this muscle shrinking than women.
If you have had carpal tunnel surgery before, you are 15 times more likely to develop this condition. Conversely, if you have had cubital tunnel release surgery, you are 11.5 times more likely to develop carpal tunnel syndrome. While many cases require surgery, mild to moderate symptoms often improve with activity changes and anti-inflammatory medications. If you have severe or long-standing symptoms, surgery can stop the problem from getting worse, but it may not fully restore normal strength or feeling.
What's actually happening
Cubital tunnel syndrome is the second most common nerve entrapment in your arm, happening after carpal tunnel syndrome. It affects between 1.8% and 5.9% of people in the United States. The problem starts with your ulnar nerve, which runs along the inside of your elbow. This nerve sits in a tight space called the cubital tunnel. Because it sits close to the skin and bone, it gets easily irritated when you bend your arm.
When you bend your elbow past 90 degrees, the space in this tunnel shrinks. The bone inside your elbow also pushes into the tunnel, squeezing the nerve. This movement stretches the nerve and reduces blood flow to it. You might feel a dull ache in your elbow or forearm, but numbness is the main issue. The nerve controls feeling in your ring and little fingers. If the squeeze continues, you may notice weakness in your hand or a claw-like shape forming in those fingers.
Sometimes the nerve slips out of its groove when you bend your arm, which makes symptoms worse. Your surgeon can tell where the problem is by checking if you feel numbness on the back of your hand. If that area feels normal, the issue is likely in your wrist. If it feels numb, the squeeze is happening at your elbow. This condition is common enough that people who have had carpal tunnel surgery are 15 times more likely to develop this problem later.
What we can do about it
Your journey often begins with self-management and physiotherapy. You might try resting your elbow and avoiding positions that bend it for long periods. A physiotherapist can guide you through exercises to keep the nerve moving smoothly. This approach aims to reduce irritation without surgery. You should give this time to work, as many patients find relief through these conservative measures alone.
If symptoms persist, your surgeon may discuss medical management. Pain medication or anti-inflammatories can help manage discomfort. In some cases, injections are used to reduce swelling around the nerve. While the evidence highlights the safety of local anaesthetic injections for visualization and pain control, specific drug types like cortisone or PRP are not detailed in the provided data. The goal is to calm the nerve and allow you to function better while you continue with non-surgical care.
Surgery is considered when conservative care reaches its limit or if you have specific signs like the nerve slipping out of place. Your surgeon might recommend a procedure to release the tight tissue around the nerve or move it to a new spot. This is done to stop the nerve from being pinched further. Most patients experience relief of symptoms after this surgery, though a small number may need a second operation.
When to see someone
See your GP if you have persistent pain or numbness in your little finger and ring finger that does not improve with rest. Ask for a specialist review if you notice muscle wasting in your hand, grip weakness, or symptoms that wake you at night. Cubital tunnel syndrome is common, affecting between 1.8% and 5.9% of people. While many cases start with mild numbness, severe cases can lead to clawing of the hand. If you have had carpal tunnel surgery before, you are 15 times more likely to develop this condition. Early treatment helps prevent permanent nerve damage. If symptoms return after surgery, 77% of patients still see improvement with further care.
