Ulnar Nerve Decompression
The Condition
The ulnar nerve lies at the back of the elbow. The ulnar nerve supplies sensation to the little finger and ring finger and the same side of the hand and wrist. The nerve also supplies the small muscles of the hand which allow delicate tasks to be performed such as doing up a button or sewing.
Each time you bend and straighten your elbow the nerve travels to and fro in a “tunnel”. Because of the shape of the tunnel, the constant rubbing causes thickening of the tissues around the nerve and this can squeeze the nerve and give rise to pain, weakness and/or numbness.
When the nerve is compressed or squeezed in this way, patients invariably have numbness or pins and needles in the little and ring fingers and difficulty in carrying out fine tasks, such as picking up pins from a table top or doing up buttons.
The Treatment
If the nerve squeezing or compression is not severe, electrical tests can be useful to see how bad the “squeezing” is. If the nerve is not being badly compressed, then surgery may be either not needed, or you may be advised that surgery is required.
Some patients may have severe numbness and although the diagnosis is not in doubt, we need to know how badly the nerve is squeezed, so that we can give a prediction as to how much recovery you may have after surgery. For those patients who have severe numbness, and gross weakness of being able to carry out find tasks, then electrical tests are useful to gauge how much recovery is likely.
If the nerve is badly squeezed, after surgery the recovery may not be complete but at least the nerve will not continue to get worse.
The Operation
A small wound is made at the back of the elbow under a general anaesthetic – you will be asleep.
The nerve is released and the wound closed with stitches and a large bandage is put around the elbow. Local anaesthetic is put into the wound so that when your elbow wound will not be painful and your fingers will feel a bit numb because of the local anaesthetic. This effect can take 6 – 8 hours to wear off.
Surgery is carried out as a day case and you will be seen again in the clinic 10 days after surgery, for removal of the bandage and removal of the stitches. You will need to keep your arm dry while it is in the bandage.
After the Operation
Once the bandage has been removed and the stitches have been taken out, you are free to get your arm wet and use the arm freely. The elbow will feel stiff for a week or two after surgery.
Usually symptoms of pins and needles and numbness settle very quickly after surgery but the longer the nerve has been squeezed, the longer it takes to recover. If the nerve has been very badly squeezed, and your fingers have been completely numb, then as the nerve recovers it will feel painful in the first instance before sensation gradually returns. For very severe numbness it can take as long as 12 – 18 months before recovery is complete. Full recovery, on occasions, is not seen when there is very severe numbness before surgery.
The usual time off work after the operation is 2 – 3 weeks if you are doing office-based work, or longer if you are doing heavy manual work. If you are a car driver, you will be able to get back to driving within a couple of days after the bandage has been removed.
Risks of Surgery
- The nerve may not improve after simply “unsqueezing” the nerve. If the nerve lies in a very tight tunnel, further squeezing of the nerve can occur despite it being freed off satisfactorily at the time of surgery. The nerve may then need not just unsqueezing from its “tunnel” that is tight, but may need to be moved nearer to the front of the elbow, so that it is not lying in the tunnel at all. This operation to move the nerve is carried out as a day case operation with a similar 10 days in bandage, and 2 – 3 weeks off work after this operation.
- The usual risks of any wound can include infection, but that is very rare after this operation.
- The wound may feel very over-sensitive in the weeks after the operation, but usually responds well to massaging the elbow with E45 of similar hand cream.
Green – Textbook of Hand Surgery
Bulstrode – Textbook of Orthopaedic Surgery
Internet sites:
www.mayoclinic.com www.orthogate.com