Cubital tunnel Syndrome
Cubital Tunnel Syndrome
What is it?
The ulnar nerve is one of the three important nerves for hand function. Nerves are important for transmitting electrical signals to and from the brain to muscles and skin. This allows us to feel sensation through our skin and move our fingers etc. with muscles supplied by the nerve. The ulnar nerve supplies feeling/sensation to the skin of the little finger and half of the adjacent ring finger, some of the muscles that bend the little and ring fingers and some of the small muscles in the hand and thumb. The ulnar nerve can be squashed or stretched as it courses around the elbow, behind a bone called the medial epicondyle. When we hit our “funny bone” we are catching the ulnar nerve – giving the unpleasant pins and needles/numbness sensation.
Cubital tunnel syndrome symptoms usually include pain, numbness and/or tingling. The numbness or tingling most often occurs in the ring and little fingers. The symptoms are usually felt when there is pressure on the nerve, such as sitting with the elbow on an armrest, or with repetitive elbow bending and straightening. Often symptoms will be felt when the elbow is held in a bent position for a period of time, such as when holding the phone, or while sleeping. Some patients may notice weakness while pinching, occasional clumsiness, and/or a tendency to drop things. In severe cases, sensation may be lost and the muscles in the hand may lose bulk and strength.
What are the Causes?
Such sustained bending of the elbow may tend to occur during sleep. Sometimes the connective tissue over the nerve becomes thicker, or there may be variations of the muscle structure over the nerve at the elbow that can produce pressure on the nerve. There may be an extra muscle that can cause direct compression of the nerve (anconeus epitrochlearis). Cubital tunnel syndrome occurs when the compression, or stretching of the nerve is significant and sustained enough, to disturb the way the ulnar nerve works.
Available Treatment of Cubital Tunnel Syndrome
When symptoms are severe or do not improve, surgery may be needed to relieve the pressure on the nerve. There are two types of surgery. The first is a cubital tunnel release, this involves releasing any constricting bands of tissue over the surface of the nerve. This removes any element of compression on the nerve but does not help if the problem is caused by the nerve being stretched. The second type of surgery is a more extensive operation which involves moving or “transposing” the nerve to the front of the elbow, which relieves pressure and tension on the nerve. The nerve may be placed under a layer of fat, under the muscle, or within the muscle. Some surgeons may recommend trimming the bony bump (medial epicondyle). Following surgery, the recovery will depend on the type of surgery that was performed. Restrictions on lifting and/or elbow movement may be recommended. Therapy may be necessary. The numbness and tingling may improve quickly or slowly, and it may take several months for the strength in the hand and wrist to improve. Cubital tunnel symptoms may not completely resolve after surgery, especially in severe cases where there is muscle wasting.
Once the wound is well healed the scar and surrounding tissues should be massaged using small circular movements to reduce the sensitivity. You can rub simple hand cream or pure vegetable oil into the scar to soften it, for five minutes several times a day. You may need physiotherapy/hand therapy for elbow mobilisation and further management of the surgical scar. There is usually no need for physiotherapy.
What are the potential complications:
Infection, Painful/tender/thickened scars and more:
Infection – Uncommon occurs in approximately 1% of operations and usually treated very successfully with antibiotics. Very rarely would require further surgery
Delayed healing – Smokers and those with diabetes are more prone to this
Painful/Tender/thickened scars – the vast majority of patients complain of some discomfort around the scar but it generally resolves with time. Wound care and desensitization as directed by your physiotherapist/hand therapist will improve this.
Nerve injury – small nerves that supply the skin around the scar may be injured giving a numb patch or unpleasant sensation round the scar. The use of magnification glasses (Loupes) by your surgeon and very careful dissection will be used to minimise this complication
Stiffness – Operations to the elbow may cause stiffness, this can be minimized by working closely with your hand therapist and getting your hand moving as early as possible.
Incomplete resolution of your symptoms – this may occur if you have had severe compression of the nerve, or have had the symptoms for a long time
CRPS – complex regional pain syndrome, this is an uncommon but serious complication. It can on rare occasions leave you with a less function hand with on-going pain stiffness and swelling. See section on CRPS. The exact incidence or rate of CRPS after surgery is unknown. It probably occurs in a significant form in approximately 1-2% of cases.