Carpal Tunnel Syndrome
Carpal tunnel syndrome is due to irritation or compression of the median nerve within a tunnel at the wrist (Picture 1). This tunnel is formed of wrist bones and a tight ligament at the top, so cannot expand. This condition is very common with community prevalence between 1.5-5%, sometimes even higher.
When the median nerve is compressed, its own perfusion (blood supply) is compromised. This is clinically expressed as tingling of the thumb, index and middle fingers (the commonest distribution), increased clumsiness, finger weakness and occasionally pain which worsens at night. The nerve can gradually wither if the condition is not treated. This causes permanent loss of sensation and wasting of thumb muscle, which may not be completely relieved even by adequate surgery.
Very mild forms of carpal tunnel syndrome might resolve spontaneously or improve significantly without any medical input.
If the symptoms are mild and intermittent, carpal tunnel can be controlled with wrist splints usually worn at night, administration of steroid injections and/or hand therapy (median nerve gliding exercise, carpal bone mobilisation, ultrasound). Hand rest, most commonly with a wrist splint may bring relief in 34-49% of cases. There is poor evidence to suggest that work place modifications (ergonomic adjustments) or physiotherapy help in the management of work related carpal tunnel syndrome. No effect is demonstrated with use of diuretics, NSAIDs, vitamin B6. Surgery is recommended if you have had the problem for a long time, above measures failed to improve condition, your symptoms are severe, or if there is wasting of muscles in the hand. Surgery involves cutting of the ligament over the tunnel to relieve the pressure of the nerve.
The commonest investigation performed for the carpal tunnel syndrome 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.
Carpal tunnel syndrome is commonly seen in pregnancy. In such situations, a clinical decision has to be made on weather only splint and injections are to be used or patient should be operated. If the patient has a debilitating / severe carpal tunnel operation may be indicated and as it is done under local anaesthetic it is not harmful.
The operation is performed under local anaesthetic on a day care basis. If patients are particularly anxious, it is possoble to arrange for procedure to be done under general anaesthesia, but in my practice, this has been very arare. Operation lasts approximately 15 – 20 minutes. The hand will be dressed with a supportive bandage that permits finger movement and light hand use (Picture 2). You will wear a bulky dressing for the first 3 days only. After that time, a simple sticky plaster would suffice until wound is healed, between 10-14 days . The scar will continuie to improve over the months to come – become thinner, softer and paler (Picture 4). The sutures are removed approximately 2 weeks after surgery. I personally prefer to use non-dissolving stitch which cause no skin reaction and which are removed easily, without any discomfort in the clinic. It is possible to use absorbable (dissolving) stitches instead if patient has such preference. Wound can get wet from day 7.
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 a holiday
Your pain at night should settle immediately but tingling in the fingers may take some weeks to disappear. As the nerves grow back, the fingers can actually feel tingly or even unpleasant. Thumb strength is regained after few months.
Recovery can sometimes be very slow (12-18 months), but most patients notice a significant relief straight after operation and continuous improvement over the following weeks.
You can drive a car after 2 weeks as long as you are comfortable and have regained full finger movements. Timing of your return to work is variable according to your occupation and you should discuss this.
Please note that patients who had very numb fingers for a very long time and/or wasting of the thumb muscles before surgery will probably never regain full nerve function.
Risks and side effects of surgery:
Complications are rare, but as with any surgical procedure, there are general and carpal tunnel release -specific risks which patients should be aware of:
- Skin/wound infection
- Scarring – the scar will take up to a year to mature. Scar massage after your surgery will help to reduce discomfort. In some cases the scar can become thickened, red and painful, known as either a keloid or hypertrophic scar.
- Hypertrophic (lumpy and itchy) scarring
- Stiffness – if fingers are not mobilised very early
- 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
Things to look out for
- 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 temperature in the area
- Strange smells coming from the wounds.
If you notice any of above symptoms in the first few days, feel free to contact the team on numbers below.
This leaflet provides only basic and generic information, but full details and explanations are provided at the consultation as no two patients are the same and personal circumstances vary greatly between individuals.
If you have any concerns following your surgery please contact:
Ashtead 01372 221 442; St Anthony’s 020 8337 6691; Parkside 020 8971 8000
Picture 1: Carpal tunnel anatomy
|Hospital stay||Day care|
|Anaesthetic||Local (no starving required)|
|Surgery time||30-45 minutes|
|Wound healing||2 weeks|
|Hand therapy||not required|
|Washing||from week 1|
|Time off work||1-2 weeks for office based work; 3-4 weeks for manual work|
|Sports and exercise||from week 2|
|Driving||from week 2 (automatic car week 1)
please check details with your insurance company
|Full recovery||4-6 weeks|
Picture 2: Bandage for the first 2-3 days
Picture 3: inner dressings (7-10 days)
Picture 4: scar after 6 weeks