Cubital tunnel syndrome is a condition that affects the ulnar nerve where it crosses the inside edge of the elbow. In that area, the nerve runs through a passage, usually rather narrow, called the cubital tunnel formed by muscle, ligaments, fascia and bone. When this area becomes irritated from injury or pressure or the nerve becomes too swollen for its narrow diameter, so called cubital tunnel syndrome occurs. The symptoms are similar to the pain that comes from hitting the ‘funny bone’.

The ulnar nerve is very important – it extends from the neck all the way into the hand and supplies feeling to the little finger and half of the ring finger. It innervates the muscle that pulls the thumb into the palm of the hand, and controls a vast majority of the small muscles (intrinsics) of the hand. This is why, its pathology, including the cubital tunnel syndrome, if not treated adequately, can lead to profound weakness and disability in the hand.

Numbness on the inside of the hand and in the ring and little fingers is an early sign of the cubital tunnel syndrome. The numbness may develop into pain. The tingling is often felt when the elbows are bent for long periods, such as when talking on the phone or during sleep. The hand and thumb may also become clumsy as the muscles become weak.

The commonest investigation performed for the cubital tunnel syndrome in my practice is the nerve conduction study (NCS). This test measures objectively electrophysiological function of the nerve i.e. speed and quality of signal transmission through the nerve. Investigation is carried out and interpreted by neurophysiologists. It adds invaluable data against which improvements can be compared, but it also adds few extra days before reliable diagnosis is made and/or treatment commenced. Personally, I prefer to reserve NCS for atypical clinical presentations, recurrent disease, suspected other causes of nerve compromise, medico-legal assessments etc.

The early symptoms of cubital tunnel syndrome usually lessen if you just stop activities which trigger the symptoms – bending of elbow, straining of specific forearm muscles etc. If your symptoms are worse at night, a lightweight plastic arm splint or athletic elbow pad may be worn while you sleep to limit movement and ease irritation.

Occupational therapists can give you tips how to rest your elbow and do activities without putting extra strain on your elbow. Sometimes they apply heat or other treatments to ease pain. Exercises are used to gradually stretch and strengthen the forearm muscles.

If nonsurgical treatments are successful, you may see improvement in four to six weeks.

It always helps to plan things in advance of surgery and adjust work and life activities accordingly. Therefore, please consider the following issues prior to your operation:

• Anticoagulation medication (Aspirin, Brufen, Warfarin, Clopidrogel) should ideally be stopped few days before the operation to reduce the risk of bleeding, but advise from the clinician who prescribed them is wise beforehand. I would strongly advise you to stop smoking prior to surgery as this can badly affect the outcome of surgery and increase complication rates.
• Please make sure that you arrange to be collected from the hospital as you will not be able to drive after the surgery
• Plan your time off school / work / sports
• Allow at least few weeks after surgery before considering holiday

Surgery is indicated when conservative measures fail and/or compression of the nerve and symptoms are severe and long standing.

The goal of surgery is to release the pressure on the ulnar nerve where it passes through the cubital tunnel. There are three main types of operations: simple nerve release by tunnel opening, medial epicondylectomy and ulnar nerve transposition. All are preformed under regional or general anaesthesia on a day care basis so you can expect to go home on the day of surgery.

Simple nerve release (tunnel opening)

This is the simplest and by far, the commonest method that I use for my patients. It predictably leads to excellent results.

Operation takes approximately 30 minutes. Cut in the skin in made between two bony prominences on the inner edge of the elbow. Roof of the tunnel is incised and left open relieving the pressure of the nerve immediately. The nerve is then examined throughout its course, above and below the tunnel (approximately 15-20cm) checking and releasing any other compression points, especially near the strong muscles which surround it. Once all is confirmed to be all right, skin is closed finely. Picture in the Gallery below illustrates appearance of the scar at 4 weeks post surgery.

Medial Epicondylectomy

This method removes a bony spur (called medical epicondyle) in the inner side of the elbow usually in addition to release of the nerve. By removing the medial epicondyle, the ulnar nerve can slide through the cubital tunnel without pressure from the bony bump. Operation usually lasts 30-45 minutes.

Ulnar Nerve Transposition

With this operation the ulnar nerve is moved (transposed) from its tunnel at the back of the elbow, to a completely new tunnel at the front of the elbow created from the muscles. Such intervention is required for more complicated pathologies and often, repeated surgery. It lasts approximately 1 hour.

At the end of all procedures, elbow is wrapped in straight position with a rather bulky bandage. Dressings are intentionally thick as this will prevent your ability to bend the elbow, which can put more strain and pain on operated nerve in the first 2 weeks after surgery. Multiple layers of soft bandage preclude the need for application of elbow cast, although this is unavoidable after ulnar nerve transposition.

Dressings are left intact for the first week, when you are likely to be reviewed by the nurse for the first time. Wound is then checked and dressings reduced. Full elbow flexion should be avoided for the next 2 weeks. The first follow up in the clinic, with me is usually at 2 weeks post surgery, but this can be even earlier if there are unexpected concerns.

The sutures are removed at 2 weeks after operation. I personally prefer to use a single, non-dissolving stitch which causes no skin reaction and which is pulled out easily without any discomfort. It is possible to use absorbable (dissolving) stitches instead if patient has such preference. Scar is usually hardly noticeable after few months and poses no cosmetic concerns.

Fingers and wrist should be moved gently straight after surgery (whilst bandage is on) in order to prevent stiffness. Pain and symptoms generally begin to improve straight after surgery, but you may have tenderness in the area of the incision for several weeks.

If you had a nerve release or the medial epicondyle excision, the therapy can progress quickly. Treatments start out with range of motion exercises after 2 weeks and gradually work into active stretching and strengthening. You need to be careful to avoid doing too much, too quickly.

Therapy goes slower after ulnar nerve transposition surgery. You could require therapy for up to three months. This is because the flexor muscles had to be sewn together to form the new tunnel. Your elbow will therefore have to be placed in a splint and immobilized for three weeks. Supervision by hand therapist is helpful for few weeks after this type of surgery.

Things to look out for after operation and contact us earlier than planned:

• Disproportionate swelling and pain in your hand
• Signs of infection in vicinity of the operated area i.e. hand/wrist are very hot, prominent redness, pain, swelling, puss collection
• Grazing of the skin (and possibly fluid leaking/oozing from the wounds)
• Increased skin temperature in the scar area
• Offensive wound smell

Complications are rare, but as with any surgical procedure, there are general and cubital tunnel release -specific risks which patients should be aware of:

General complications:

• Adverse reaction to the anaesthetic
• Skin/wound infection
• Hypertrophic (lumpy and itchy) scarring

Procedure specific complications:

• Pillar pain – this is due to disconnection of two mounds of hand muscles following carpal tunnel release. You may find that your grip is weaker than previously and leaning against the palm uncomfortable. This will gradually improve over 6 months
• Complex Regional Pain Syndrome (CRPS) – rarely people are sensitive to hand surgery and their (seen in 5% of surgery) hand may become very swollen, painful and stiff after any operation. This problem cannot be predicted but will be watched for afterwards and can be treated with medication and hand therapy
• Persistent weakness / numbness – You may find that your grip is still weak after the surgery. This normally improves but depends on how long you had the condition before the operation and how much irreversible muscle wasting had occurred