What is it?
Symptomatology – Carpal Tunnel Syndrome
Carpal tunnel syndrome is also known as median nerve entrapment. Typical symptoms are pain and paraesthesia (altered sensation) in the thumb, index, middle and half of the ring finger. It is often worse at night. Patients complain of tingling which wakes them from sleep, they have to shake the hand and hang the hand over the edge of the bed to relieve it. Symptoms can be worse on driving or using the phone. It can progress to significant weakness in the hand also.
Carpal tunnel syndrome can be associated with other medical conditions including rheumatoid arthritis, diabetes, hormone problems, hyperthyroidism, pregnancy and previous trauma.
The diagnosis of carpal tunnel syndrome is based on three features:
1. History – does it fit?
2. Examination – do you have positive findings? Nerve function will be assessed clinically.
3. Nerve conduction studies – are they normal? The nerve tests may support the diagnosis but may not necessarily be diagnostic of carpal tunnel syndrome.
In my practice if patients present with two out of the three of the above and if symptoms are severe then I may consider surgery. If symptoms are mild and only occur occasionally at night then a simple night splint may be tried. This can be enough to relieve symptoms particularly in elderly patients.
Only very occasionally will a steroid injection into the carpal tunnel be considered, particularly if symptoms are very mild and on early presentation. Current literature shows that if you have moderate to severe symptoms then the recurrence rate following a steroid injection is extremely high. For mild conditions twelve months down the line one can get satisfactory results.
Having failed conservative treatment and with persistent daily symptoms, I would advise surgical decompression. This is a short procedure which takes approximately 10 to 15 minutes, it is carried out under local anaesthetic (you are awake for the procedure), this involves you lying flat with the arm to the side. An injection is placed at the wrist to numb the palm of the hand. This can be a little painful but once the injection takes effect you will have no pain at all. A tourniquet (blood pressure cuff) is applied at the top of the arm, this is inflated during surgery so that there is no blood in the hand and the structures can be easily identified. A small one inch incision is made at the base of the palm, the ligament forming the roof of the tunnel is divided which allows the circulation to get into the nerve more freely. The skin is closed with sutures and a small bandage is applied. The bandage is removed after two days and you will need to keep the wound clean and dry for two weeks. Sutures are removed at two weeks. The success rate for this procedure is extremely high. The pain and paraesthesia should almost resolve on the night of the operation. There are some risks associated with the surgery in terms of infection, swelling, bleeding, stiffness of the fingers, numbness around the edge of the wound and pain. The most common concern for patients who have undergone this operation is the scar. It is not the appearance of the scar, but the scar can be quite sensitive and painful. Once the sutures have been removed patients are encouraged to apply regular moisturisers and oils and massage it. This will resolve eventually but can take three to five months to completely settle on the rare occasion.
Symptomatology – Trigger Finger / Trigger Thumb
Trigger finger or trigger thumb is a painful locking sensation in the digit. The digit often gets stuck in a bent position and on attempting to straighten it there is a painful click. It can start initially with pain on movement of the finger and swelling and then it progresses to locking. Sometimes the pain can be felt over the back of the finger and a sensation that it may be coming from the joint of the finger. This is not the case with the pathology of this condition.
As the tendons or guides run to your fingers, when they get beyond the distal part in the palm they run inside a sheath, if the tendon becomes swollen then it does not glide in and out of the sheath in the appropriate manner. This then leads to locking as the tendon struggles to get back into the sheath on straightening the finger.
This condition can be associated with other medical conditions such as inflammatory arthropathy, rheumatoid arthritis and diabetes.
If a patient presents early with this condition and has mild to moderate symptoms then a steroid injection can be very beneficial. The spectrum of symptoms can be just painful crepitus (crunching feeling on wind up of the finger), locking to the extent that one has to use the other hand to try and straighten the finger or the finger may become permanently locked. With mild forms of this condition injection has a definite benefit and a steroid injection can be carried out in the clinic or in theatre. The hand is cleaned and the injection is performed in and around the sheath of the flexor tendon. This helps to reduce the swelling and allows the tendon to glide more freely. As the palm is very sensitive this can be quite a painful injection.
Following the injection the finger will be quite swollen and painful for anywhere between two and five days. The steroid may take up to a week or so to work.
If steroid injection is not successful then surgical intervention should be considered to restore function to your hand. Surgery is carried out as a day case under local anaesthetic and takes ten to fifteen minutes. In theatre your hand will be cleaned with antiseptic, a tourniquet (blood pressure cuff) is applied to the upper arm and inflated. This can be a little tight. The palm of the hand will need to be injected with local anaesthetic and an oblique incision is made in the palm of the hand, or base of the thumb. The nerves and vessels are protected and the sheath is divided over the flexor tendon over the course of approximately one centimetre. This is usually sufficient to allow the tendon to glide more freely. The wound is closed with sutures and a padded dressing and bandage applied. Bandages are removed after two days and early movement of the finger / thumb is encouraged. There is a small risk of infection, the finger can be swollen and stiff for a period, there is a small risk of numbness, prolonged pain and swelling and the scar can be a little uncomfortable for up to a few months. The sutures are removed at two weeks in the clinic or GP practice and patients are encouraged to apply moisturisers and oils to massage the scar. This can be a little lumpy and painful for a few months sometimes but usually settles thereafter.
Symptomatology – Dupuytren’s contracture / disease
Dupuytren’s contracture is a disease of the fascia in the palm of the hand. The fascia in your hand in simplest terms is a bit like a layer of cling film. This lies just beneath the skin and fat and separates this from the deeper structures, i.e. nerves, vessels and tendons below. Fascia helps to facilitate grip in the palm of the hand. When there are too many of one particular cell which is known as myofibroblast and when this proliferates this causes thickening nodules and bands in the palm of the hand. These can be felt in the palm and may not cause any problems. When they cause a contracture (bending of the finger) which is non corrective, this can affect function of your hand. Most patients present with difficulties with grip, difficulties with hygiene, poking themselves in the eye when trying to wash their face, difficulty putting hand in a pocket and wearing gloves. It is not generally a painful condition. Most commonly it affects the ring and little fingers but does occasionally affect the thumb and index finger but this is not as debilitating.
The general consensus for treatment is if you cannot get your hand flat on a table then it may be worth considering surgical correction. It is your disability and your functional restrictions that you would need to consider before embarking on any treatment for this condition.
There is no real evidence that physiotherapy or night splints will prevent any progression on in a non-operated hand. If you are at a stage where your contracture is affecting your daily function and you would like to consider intervention, in my practice I offer two different treatment options as below:
Percutaneous needle fasciotomy – the advantages of this procedure are that it is done under local anaesthetic and recovery is essentially within a few days of surgery. With this condition I would be correcting the deformity but not removing the diseased fascia. The procedure is carried out in theatre, the hand is cleaned and a small amount of local anaesthetic is infiltrated into the skin to numb the hand. A needle is used to pepper the cord often in several areas like a perforated piece of paper. The finger is then gently manipulated and the diseased band should hopefully rupture allowing correction of the deformity. This is only carried out in the palm and not in the finger itself due to the risk of nerve damage. Occasionally you can get a small tear in the skin, but generally speaking there is only a pin size wound here. The hand is put in a bandage with a pressure dressing for approximately 48 hours. After this patients may fully mobilise the hand and get back to normal activities. Occasionally there can be a little skin tear which can be treated as any simple wound with a dressing for a week or so. Over 90% of patients are back to full function within five days of the surgery. This surgery is aimed at correcting the deformity but does not remove the disease. The advantages with this procedure are the rapid recovery but there is a small risk of damage to the nerves and vessels with the needle.
Open surgery – fasciectomy +/- skin grafting – If it is decided you require open procedure this is aimed at removing as much of the diseased fascia as possible in order to achieve correction of the contracture in the finger. If the diseased fascia runs into the finger this is often the option of choice. This operation requires a general anaesthetic and surgery can take between 45 minutes to over two hours depending on how many digits are involved and the extent of the disease. Surgery involves zig-zag type incisions in the palm and into the finger. The nerves and vessels must be identified and protected, diseased fascia removed. If the finger still remains contracted after this then surgical release may be carried out around the finger to try and improve the deformity. Generally speaking, if the deformity is at the knuckle joint full correction can be achieved in 90% of cases. If the deformity involves the joints in the finger itself then a full correction is often not possible. This is because the small joints of the finger themselves become stiff and contracted. Occasionally with very severe deformities, following correction can lead to a hole or defect in the skin and it is not possible to cover this with the skin that is available. It may then be necessary to take skin from a small elliptical type incision either in the forearm or upper arm. This is called a skin graft. This is then sutured into the palm in order to close the defect. At the end of the operation the hand is wrapped in non-adherent dressing and a short arm plaster cast (half plaster cast) / backslab. This needs to be worn for one week and you will require outpatient hand therapy which is just as important as the surgery itself. The hand therapist will see you at one week for removal of the plaster, cleaning of the wound and a thermoplastic splint (plastic moulded splint) to the palm. This remains in place for one more week. The sutures are removed at two weeks and then the splint is only worn at night for approximately three months. The recovery depends a lot on the severity of the deformity and other co-morbidities that you may have in terms of your general health. Smoking may increase your risk of problems with wound healing and recovery.
Average recovery is six weeks, some patients recover sooner and some may take up three to five months to recover.
The main risks are damage to the nerves and vessels, wound dehiscence, infection (the hand sweats a lot and is prone to bugs), pain, swelling and stiffness and recurrence of the disease. The hand can be swollen and stiff for quite a few weeks following this sort of surgery and this is why hand therapy is vital as part of the overall treatment for restoring function to your hand.
If you have had surgery for this condition before, then revision surgery carries higher risks in terms of nerve and vessel injury, problems with wound and overall recovery.
Xiapex / Collagenase injections – I would like to point out that enzyme injection for this disease is available at the current time. I do not offer this treatment for various reasons. The toxin injection is a form of rupture of the cord only so the mechanics of it are exactly the same as percutaneous needle fasciotomy. Instead of manually rupturing the cord with the needle an enzyme is used to dissolve and rupture the cord. This procedure is quite expensive and very labour intensive. It requires anywhere between three and twelve to fifteen consultations before potentially a full correction is achieved. Recurrence rate is currently the same as for needle fasciotomy. It is these reasons why I do not currently offer this service.