Is it cubital tunnel or carpal tunnel syndrome?

Cubital tunnel syndrome is a condition where the ulnar nerve gets compressed as it passes in and under various structures at the back of the inside of the elbow. The cubital tunnel (on the medial side) is made up of bones, muscle and tendon, and allows the ulnar nerve to pass behind the elbow from the arm into the forearm.

Compression of the nerve can be acute from injury, swelling or surgery, to chronic from tight tissues or scarring. It can be constant or intermittent due to the position of the elbow or because of direct external pressure on the elbow.

Most people have heard of carpal tunnel syndrome, which is compression of the nerve at the wrist, as opposed to cubital tunnel syndrome. Leading London orthopaedic surgeon Mr Nick Ferran discusses the differences between the two conditions and whether it is possible to have both at the same time. 

What are the symptoms?

The most common early symptom of cubital tunnel syndrome is pins and needles in the little and ring finger of the affected arm. There can also be an electric or shooting type pain from the elbow to the fingers, down the inside of the forearm. This is due to damage to the sensory fibres of the nerve. The brain perceives the pain like pins and needles at the site where the nerve supplies, not at the site of compression, so there is rarely elbow pain associated with cubital tunnel syndrome, although the problem is in the elbow.

Early on, the symptoms are intermittent and often depend on the position of the elbow. Having the elbows bent for long periods of time, such as when sleeping, can result in the symptoms that often wake patients at night. Symptoms can often be caused by reading and holding the book with the elbow bent or driving with the elbow bent for a long period of time. Intermittent sensory symptoms are reversible with treatment. When sensory symptoms become permanent, the reversibility is less predictable and can take a long time for the symptoms to resolve.

As the condition progresses, the motor part of the nerve becomes damaged and the small muscles of the hand which affect the strength of grip lose their nerve supply, become weak and eventually atrophy resulting in the muscle wasting away. Muscle wasting is permanent.
 

What’s the difference between cubital tunnel and carpal tunnel syndrome?

Carpal tunnel syndrome is a condition where the median nerve is compressed as it passes through the carpal tunnel at the level of the wrist. Like the ulnar nerve, the median nerve has sensory and motor parts, so the symptoms can be both sensory or motor. As the compression occurs at the wrist, the elbow position does not usually affect symptoms. However, in atypical cases, instead of pain shooting from the wrist into the fingers, carpal tunnel syndrome can cause pain shooting up from the wrist toward the elbow.

The median nerve supplies a different part of the hand. The thumb, index finger, and middle finger are most commonly affected. The motor part of the median nerve supplies the small muscles of the thumb so muscle wasting from damage to this nerve can cause weakness of pinch grip (such as holding a key or pen) and may result in dropping objects.

Not everyone is wired the same so sometimes carpal tunnel syndrome can affect all the fingers of the hand, but this would be considered atypical.
 

Can you have both at the same time?

It is quite common for patients to have both cubital and carpal tunnel at the same time. It is also common for the conditions to be present in both arms at the same time. When patients have numbness in all the fingers of the hand we need to examine and test for both cubital and carpal tunnel syndromes. We also need to screen for other nerve conditions that can cause numbness in both hands such has nerve compression in the neck, diabetes and other conditions that can cause peripheral neuropathy.
 

Can cubital tunnel syndrome go away by itself?

If the cause of the cubital tunnel syndrome is temporary, such as bruising or swelling from surgery or trauma, the symptoms can settle on their own. Compression of the ulnar nerve by sleeping on bent elbows can sometimes be improved by using night splints to try to keep the elbow straight during sleep, but most patients don’t get on well with these. Symptoms brought on by reading or driving with the elbows bent for a prolonged period can be improved by changing posture at regular intervals.
 

Is surgery an option?

If non-operative measures have failed, if the sensory symptoms are becoming permanent, or if there is any weakness or muscle wasting, I would recommend surgery. The surgical treatment for cubital tunnel syndrome is a cubital tunnel release or decompression. This is a minor, day-case operation that I often perform with the patient awake under regional anaesthesia. The recovery from cubital tunnel release or decompression is relatively quick.



For more information on cubital tunnel syndrome check out Mr Ferran's website and YouTube channel.

Do not hesitate to book an appointment for consultation via Mr Ferran's profile.