WRIST LIGAMENT INJURY
What is wrist ligament injury?
The wrist is by far the most complex joint of the body. It is made up of a platform of 2 bones the ends of the radius and ulna bones. On this bony platform sit a complex arrangement of another 7 bones linked by multiple ligaments between each bone and across several bones at a time both on the back and the front of the wrist. The ligaments may fail through general wear and tear presenting with problems in middle age or later (40+). The ligaments may tear following injury such as a fall, although symptoms may not develop for many tears or even decades. Ligament strain in adolescence/young adulthood may give pain and a localised cyst called a ganglion (this will not be considered further here - see information sheet on ganglion).
The Patients typically present in middle age and later (40yo and onwards) with gradually increasing stiffness/pain/deformity. They may run together or one or other may predominate. Sometime the symptoms will come on quite quickly following a sudden injury which may be quite mild but then tips the joint over from being potentially symptomatic to being symptomatic. The symptoms may increase giving marked disability due to restricted movement and pain both at night and in the day. Te symptoms in younger patients following injury are often very similar to those in middle age although younger patients more often report a sense of instability or a click or clunk with movement.
Why does it occur?
All joints require ligaments to maintain stability when loaded i.e. when used particularly when used heavily. This is even more important in the wrist because of its complexity and the its normally large range of movement. When ligaments fail the bones of the joint move abnormally one on the other. This leads to excess wear of the articular cartilage lining of the bones and will in time lead to arthritis although not necessarily much in the way of symptoms. Even before arthritis develops patients may develop symptoms: abnormal stresses on the remaining ligaments and bones may cause pain; abnormal bone movements may cause stiffness both a reduced range of movement and a sense of stiffness with that movement; and the abnormal movements may give a sense of instability in the joint particularly with heavy use.
What happens if nothing is done?
(This is referred to as the natural history i.e. what happens if Nature runs its own course.)
Some people's symptoms resolve particularly their pain especially if the activities that cause pain are avoided. Many people are left with some long-term stiffness with both a lack of full straightening (extension) and full bending (flexion) but most people can come quite well with a limited range of movement in the wrist (certainly better than some other joints). Some patients develop more pain and stiffness with time. The pain may wake them at night and can be particularly troublesome with twist loading i.e. gripping and twisting something and when taking weight on the cocked back wrist. Patients may in time develop marked pain and increasing disability in their hand affecting both dexterity and grip strength.
Making the diagnosis
The Hand specialist who sees the patient will ask questions about their symptoms, when they started, how they progressed, what treatment (if any) they have had and other questions relevant to the problems. They will then examine the patient looking at the wrists and hands. Stressing i.e. pushing on the affected joint is often uncomfortable. It is necessary to demonstrate some tenderness to confirm the site of the symptoms but this should not be too painful. The ranges of motion may be measured with an angular ruler called a goniometer.
What test(s) might be performed?
Tests (also known medically as Investigations) include X-rays, scans, blood tests and particularly in the hand electrical tests (known as EMGs or Neurophysiology). These may be used to help make or confirm a diagnosis after a patient has described their symptoms and been examined.
The diagnosis is usually obvious after listening to and examining a patient. Typically an X-ray is requested on the same day to delineate the extent of joint damage, although often the X-rays are normal with early or mild ligament in juries. If further information is required and MRI scan may be requested.
An MRI scanner is usually a short tunnel which the patient's arms and top half of the body go into. Once in the tunnel a loud magnet is spun around and images of the bones and soft tissues created. Some people find the tunnel rather claustrophobic. If any patient doubts whether they would tolerate the scan they are best advised to visit the scanner department in advance. The films will be reported by a radiologist but also reviewed by the Hand specialist who will advise the patient accordingly. The difficulty in assessing wrist ligament injury is that it is a dynamic problem i.e. related to movement and yet the tests are static i.e. non-moving tests.
What are the non-operative treatments?
Treatment should start with non-operative options. The first step is activity modification which the patient may well already have tried. Pain killers (analgesics) particularly anti-inflammatory analgesics, such as Ibuprofen (Nurofen) and Diclofenac (Voltarol) can be very helpful for the pain. These can be applied as a gel, massaging the area, or taken orally, assuming there is no history of indigestion. A wrist splint for certain activities can be of considerable value. If these measures are insufficient then a steroid injection may be recommended. An injection is given of a long-acting steroid, such as Depomedrone or Triamcinolone, with some local anaesthetic into the joint at the bottom of the thumb. The body naturally produces steroids to help dampen down inflammation. This appears to be one of the actions at this site. Success cannot be guaranteed but in 70-80% of patients there is some significant benefit. How long this lasts is unpredictable. Some people only have a few weeks or months of benefit. Others may have years or even life-long benefit such that they do not require further treatment, although may still have some mild on-going symptoms. If one injection provides only short term benefit then it may well be repeated. Patients often ask how many injections can be given. There is no set rule about this. Typically, however, a second injection will work a little less well than the first (although this is not inevitable). By the time three injections have been given, if this is over a shortish period, i.e. less than 1 year, then it is unlikely further injections will be successful and most surgeons would recommend an alternative approach. There are risks. The biggest risk is of failure. There are risks of some pain for a few days, although that is usually minimised by taking pain-killers, starting while the area is still numb from the local anaesthetic. In theory there is a risk of infection, but this seems very rare and has not occurred in our Practice in over 10 years. The main other risk is some thinning of the skin. This can present with some pallor and a little less bulk at the site and occasionally an increased tendency to bleeding if the area is knocked. This is not common with this injection but is common with some other injections. If it does occur then that is a relative contra-indication to further injections, i.e. the patient's surgeon would probably decide not to go ahead with further injections because of the risks of further local damage.
What does the operation involve?
There are several operations available for wrist ligament problems. The aim is an operation with minimal risk and reliable and successful outcomes. This does not happen in the wrist. There are a range of operations of increasing complexity and risk (although not large) but equally increasing likelihood of giving a satisfactory result. Which operation is selected is based upon the extent of the disease, surgeon preference and most of all patient preference. This reflects our treatment philosophies (see information sheet). The surgical options from simple to complex are: wrist arthroscopy and washout; wrist denervation; partial wrist fusion/excision of some wrist bones (proximal row carpectomy). Their details are as follows:
Wrist arthroscopy and washout: This is telescopic or keyhole surgery. It is performed under a regional (making the whole arm numb) or general anaesthetic. Via several (4-6) small (5mm) incisions in the back of the wrist the surgeons looks in the joint. He/she can define the details of the problem and clean out and wash out the joint which may help symptoms. The wounds do not need stitching. The wrist is covered in a bulky dressing for comfort.
The time in hospital is usually 2-4 hours.
Wrist denervation: The idea behind this operation is to cut the nerves taking pain signals from the wrist to the brain so the pain is either not felt or felt much less whilst also NOT damaging the important nerves that provide sensation and movement to the wrist and hand. To remove all the nerve supply (denervate) to the wrist fully is not really feasible. We, like many other surgeons, just divide the 2 small end nerves that lie in the middle of the end of the forearm and take the majority of the pain signals from the wrist to the brain. These nerves are called the anterior and posterior interosseous nerves (AIN and PIN). This is not a very reliable operation so the Hand specialist will typically inject local anaesthetic around these nerves at a clinic visit to assess the likelihood of success. If there is little or no benefit then the operation is unlikely to work. If the injections work for at least several hours then the operation has about a 70% chance of success. The operation is performed under local anaesthetic. A band, like a blood pressure cuff, is placed around the top of the arm. It is inflated (tightened) during the operation to reduce bleeding, which makes the operation easier and safer. It can be a little uncomfortable, but is almost always well tolerated for the 10 mins or so that it is inflated (this happens just before the surgeons starts the operation). Before that the arm is painted with an antiseptic with a pink dye in it. This is used to help minimise the risk of infection.
A 2-4 cm cut is made in the back of the distal forearm. The nerve ends are found and divided. The skin is stitched up with absorbable stitches. The wrist is covered in a bulky dressing for comfort.
The time in hospital is usually 2-4 hours.
Any further operations are only likely to treat the late stages of wrist instability where there is associated wrist arthritis.
Partial wrist fusion/excision of some wrist bones (proximal row carpectomy): These operations aim to remove the pain but retain some movement which is normally enough for most but not all daily activities. The key troublesome bone is the scaphoid bone which is the bone most commonly involved in wrist arthritis. This is removed. Unfortunately the wrist can become unstable so either the majority of the remaining bones (lunate, triquetrum, hamate and capitate) are fused together to make a simple "2 bone wrist". This is known as a scaphoid excision and four quarter fusion. This is the commonest partial wrist fusion. Alternatively the lunate and triquetrum bones are also removed and the wrist works as a joint mainly between the radius bone and the capitate bone. This is called a proximal row carpectomy. Which is performed is largely based on surgeon preference. It is performed under a regional (making the whole arm numb) or general anaesthetic. Via a 5-6 cm incision over the back of the wrist the surgeon opens the wrist and either just removes bones or also stabilises bones together with wires/screws/plates and screws. The deep tissues are closed and the skin stitched with absorbable sutures. The wrist is supported in a plaster of Paris back slab for comfort.
The time in hospital is usually one night's stay.
What happens in the next few weeks?
The care of the hand in the post-operative period is very important in helping to ensure a good result. Initially the aims are comfort and elevation. These are met by keeping the hand up (elevated) especially in the first few days and by use of a long acting local anaesthetic (Bupivicaine). The local anaesthetic lasts at least 12 hours and sometimes 48 hours. Patients should start taking painkillers before the pain starts i.e. on return home or whilst still in hospital and for at least 24 hours from there. This way most of our patients report little or any pain.
The patient is reviewed in clinic after within 2 weeks of the operation. Typically dissolvable stitches are used so they should not require to be removed. A splint may be provided by the physiotherapists particularly following joint replacement. Careful follow up is required to ensure a successful result with good relief of pain and a good range of movement.
The hand can be used for normal activity after the first few days. Wrist movement will depend upon the scale of the operation. Typically most of the movement gained following surgery occurs in the first 6 weeks but the wrist seems to be more forgiving and will regain movement quite late (even after several months) nonetheless early movement is encouraged where appropriate. The key is regular long gentle stretches both into straightening and into bending. Ideally these should be performed for 5 mins in each direction (feeling the stretch but without pain) once an hour. In practical terms most people mange 5-6 times a day. Elevation and icing the elbow also help reduce swelling and thus pain and improve movement.
Most patients can drive after a 1-2 weeks following arthroscopy or denervation, and 6-8 weeks following the larger operations. Most patients return to work following arthroscopy or denervation in 2-3 weeks, but this varies with occupation; heavy manual work usually takes about 6 weeks. Following the larger operations patients return to light work in 6-8 weeks and heavy work not before 3 months if ever.
The scars should be massaged by the patient 3 times a day with a bland soft cream for 3 months once the wound is well healed (typically after 2 weeks). This reduces the scar sensitivity which can be a nuisance.
What are the results of the operation?
The results vary from operation to operation. By and large the number of satisfied patients is as follows:
Wrist arthroscopy and washout: 70% satisfied. Range of movement unchanged or slightly improved.
Wrist denervation: 70% satisfied. Range of movement unchanged or slightly improved.
Partial wrist fusion/excision of some wrist bones (proximal row carpectomy): 80-85% satisfied. Range of movement reduced but normally around 40-50% of normal.
Are there any risks?
All interventions in medicine have risks. In general the larger the operation the greater the risks. For wrist surgery the risks include:
- The scar may be tender, in about 20% of patients. This usually improves with scar massage, over 3 months.
- Aching at the site may last for several months
- Grip strength can also take some months to return to normal.
- Stiffness may occur in particular in the fingers. This is usually short-term and only infrequently requires physiotherapy. But it is very important that it is resolved quickly to avoid permanent stiffness. This occurs rarely but can do associated with CRPS (see below)
- Numbness can occur around the scar but this rarely causes any functional problems.
- Wound infections occur in about 1% of cases. These usually quickly resolve with antibiotics.
- For partial joint fusion there is a risk of failure to achieve bone to bone union of to gain union with some malalignment. Either may (but not of necessity) require reoperation.
- Chronic Regional Pain Syndrome "CRPS". This is a rare but serious complication, with no known cause or proven treatment. The nerves in the hand "over-react", causing swelling, pain, discolouration and stiffness, which improve very slowly.
- Any operation can have unforeseen consequences and leave a patient worse than before surgery.