Background to elbow replacement surgery
The operation of total elbow replacement is designed to relieve the symptoms of arthritis in the elbow. Although, in common with other joint replacements, it is a very successful operation, it is a complex procedure which does have some hazards and it should only be undertaken for significant symptoms.
It is only the patient who knows how severe their symptoms are but reasonable guidelines are as follows. The surgery is indicated if your elbow is preventing you from performing normal day to day tasks such as eating, cooking, writing, reading and similar activities.
The main benefit of total elbow replacement is the relief of pain so you should consider the operation if you are troubled by pain on a regular basis so that it interferes with activities or it interferes with sleep.
If your elbow is stiff the surgery will usually produce some increase in flexion or bending of the joint but the joint will not fully extend, ie. the arm does not usually come completely straight. The operation will usually improve pain and stiffness in pronation and supination of the forearm, ie. turning the forearm over and over.
What is the elbow joint like?
The elbow joint is the joint between the lower end of the humerus or upper arm bone and the upper end of the ulna which is one of the two bones in the forearm. The elbow is a hinge between these two bones which has a small amount of laxity in the hinge itself.
The forearm is able to rotate because the two bones in the forearm turn over each other. At the elbow end of the forearm the ulna is the larger of the two bones which makes the lower part of the hinge. The tip of the ulna is called the olecranon and this is the bone that you feel at the point of your elbow. The radius at the elbow has a small, round end which is able to turn. At the wrist end of the forearm the radius is the larger of the two bones which you can feel at the base of your thumb. The ulna at the wrist has a small round end which you can feel on the little finger side of your wrist.
During an elbow replacement the upper end or head of the radius is removed to allow free rotation of the forearm. If the head of the ulna at the wrist is very stiff then this sometimes needs to be removed as well (in about 2-3% of patients) to allow free rotation of the forearm. The surfaces of the two bones involved are covered with cartilage which is a shiny white lubricated surface. The elbow joint is stabilised partly by the shape of the joint but also by ligaments either side of the joint. The ligament on the inside of the joint is particularly important in stability.
The process of arthritis is the destruction of the articular cartilage surface of the joint. There are two main types of arthritis which affect the elbow. Most elbow replacements are carried out for rheumatoid arthritis and similar types of arthritis such as psoriatic arthritis. Rheumatoid arthritis is a disease rather than being a simple wearing out process. In rheumatoid arthritis the lining of the joint is inflamed and it is this inflammation which damages the joint surface.
Osteoarthritis is a condition in which the articular cartilage wears out. It can be caused by major injuries to the joint. It is more common in people who have used their elbow intensively for work over a long period of time, for example, workers in old fashioned metal casting factories. A lot of the cause is genetic and elbow osteoarthritis is seen in people who have no particular work history. The condition runs in families and it is a common part of the ageing process. Osteoarthritis is nothing to do with osteoporosis which is a thinning of the bones which causes fractures but does not cause arthritis.
Total elbow replacement is not commonly carried out for osteoarthritis. The reason is that if you have an elbow replacement and then use it vigorously for work activities or even just for heavy gardening, the joint does tend to wear out quite quickly. Elbow replacement is therefore reserved in osteoarthritis usually for people over the age of 70 with limited requirements for heavy activities.
Younger patients who may need to use their elbow for heavier activities over a period of years are best treated by elbow debridement which is a procedure in which the osteoarthritic bone is removed from the joint and the capsule is freed up to allow more movement.
How is the joint replaced?
The elbow joint is opened from the back of the elbow using an incision which runs on average 15cm (6 inches) down the back of the elbow. The lower end of the tendon of the triceps muscle, which is the big muscle in the back of the upper arm is turned down to its attachment to the tip of the ulna. The elbow joint is then opened and any inflamed synovium is removed. The head of the radius is removed at this stage.
Following this the joint is dislocated. The trochlear or hinge part of the humerus is removed and the joint surfaces of the ulna are removed. The lower end of the shaft of the humerus and the upper end of the shaft of the ulna are prepared using a small burr similar to that used by a dentist. The preparation of the joint for fitting of the implants is significantly more complex than in the hip joint for example, which is a simple ball and socket. There are trial implants which are fitted to the bones to check the elbow for tension and alignment.
Assuming all is well the two components are fitted to the bone using bone cement. Bone cement is a plastic cement which is mixed from two components. It grouts into the bone and it sets solid in about ten minutes. Over the few months after the surgery the cut surface of the bone regrows in close adhesion to the bone cement. The component fitted to the lower end of the humerus is made from chrome cobalt. The component fitted to the ulna is made from polyethylene. The two components are available in a variety of sizes and they can also have longer stems on them to cope with moderate degrees of bone destruction which can be caused by the arthritis. After the implants have been cemented the ligaments around the elbow joint and the tendon of the triceps are carefully repaired using multiple small stitches. This repair process is vital for the stability of the joint. At the end of the operation the ulnar nerve, which is the nerve of the funny bone, is released to reduce the risk of it suffering from the bruising which inevitably occurs after the joint replacement.
The elbow replacement that I routinely use is a Souter-Strathclyde total elbow replacement which was developed by Mr William Souter of Edinburgh working with Strathclyde University. Alternatively if there is a lot of bone destruction or if there is unusual anatomy I use a Coonrad-Morrey total elbow replacement which was developed by Dr Bernard Morrey of the Mayo Clinic in the United States.
Risks and benefits of total elbow replacement
Overall total elbow replacement is a remarkably successful operation. In its early days it had a very bad reputation for component loosening, wound infection and similar drastic complications. The Souter elbow replacement has been used by a number of groups around the world with results which are comparable to other types of total elbow replacement. Over the past fifteen years I have performed just under one hundred total elbow replacements using both the Souter and the Coonrad-Morray implants.
My results of Souter total elbow replacements were reviewed by Mr Ian Pitman for the purposes of an MSc thesis. At that time reviewing the results of seventy replacements he found that they had around a 90% chance of working satisfactorily for a period of ten years. The main benefit of the operation is relief of arthritic pain. Many people who have a total elbow replacement still know that they have an artificial joint, although in some patients it feels completely natural. Most patients get rid of the great majority of their arthritic pain, if not every ache and pain around the joint. Obviously some people with severe rheumatoid arthritis are still held back by their shoulder or by their wrist and hand.
The surgery is a lengthy and somewhat tricky procedure which has occasional very serious complications. The complication that we worry about most is infection. If the artificial elbow becomes infected it certainly has to be operated on again and the problem can leave the patient every bit as bad as they were to start off with, particularly if the infection cannot be fully eliminated. The incidence of infection in my total elbow replacements at the Royal Orthopaedic Hospital currently is zero. Having performed around one hundred joint replacements there is probably an element of luck here and I would expect the risk to be around 1-2%. The risk of infection in joint replacements is higher in patients with rheumatoid arthritis, diabetes, obesity and other medical problems. Bearing in mind these factors and looking at results from other series I would say that the risk is around 2%. There are risks of damage to nerves and blood vessels around the elbow. Damage to blood vessels at the elbow is a rare but serious complication.
Damage to the ulnar nerve at the back and inside of the elbow is a little more common. The ulnar nerve is a key nerve which wraps around the elbow. It is the nerve which causes the symptoms when you hit your funny bone. It is responsible for sensation in the little finger particularly and for movement of the small muscles of the hand. A lot of cases of malfunction in the ulnar nerve will correct themselves over a period of weeks or even months after the surgery, however a small number of patients are left with a permanent problem. The risk is probably around 0.3% or so. Such patients are troubled by numbness and sometimes pain in the little finger and by difficulty with fine movements of the hand. For practical purposes a lot of the patients involved often have difficulty with the hand moving anyway so there may not be a huge amount of practical difference to their function. The risk to the patient’s life from a total elbow replacement is very small but it cannot be totally ignored. For a fit individual the risk is probably similar to other joint replacements at around 3%. Elbow joint replacement is less of a shock to the system than a total knee replacement but the surgery lasts rather longer. The risk is obviously higher in people with medical problems and it is probably a bit higher in patients over the age of 80. The main medical complications are heart attacks during or after the surgery and the formation of blood clots in the legs which may float off to the chest with dire consequences. The risk of this happening can be reduced in a high risk patient by giving the patient regular doses of Aspirin or anticoagulants around and after the time of surgery.
One of the key risks of total elbow replacement is the joint dislocating or coming out of joint. This complication occurs in a small percentage of cases early on, similar to total hip replacement. In total elbow replacement however the dislocation usually occurs when the repair of the triceps attachment to the ulna comes apart in the early post-operative period, so the patient has to be taken back to theatre for the muscle to be re-repaired and sometimes reinforced. I have had to do this on a few occasions and fortunately there have not been any patients with long term episodes of recurrent dislocation. The bones of the elbow in rheumatoid are always very fragile so there are other complications such as fracture of the lower end of the humerus. This can occur during surgery and there are special implants designed to cope with this situation. Also the ulna can break in the post-operative period. This means another operation but there are again implants designed to cope with this complication.
Overall therefore the risk of a major complication from the surgery is probably around 2-3%. Between the 90% of operations which are very successful and the 2-3% where there is some major problem, there is a group of 5-10% of patients who have a slightly suboptimal result, the procedure is not a disaster but it is spoiled by some problem, particularly excessive ongoing stiffness in the elbow and ulnar nerve tingling. The operation is not a disaster by any means but it is not as good as some. In the long term the results are as documented in Ian Pitman’s study. Around 90% of total elbow replacements are still working ten years after the surgery, although some of these patients have had further surgery. I do have some patients with well functioning total elbow replacements between ten and fifteen years post-surgery. Overall in the long term between five and fifteen years post-surgery total elbow replacements probably cause more trouble than total hip and total knee replacements, particularly due to loosening of the humeral components. Fortunately when the Souter humeral components loosen they often only damage the very lower part of the humerus so that they can be revised using longer stem components or the Coonrad-Morrey implant.
The care of the patient before and after total elbow replacement
Prior to your surgery it is important that you tell the treating team and the anaesthetist about any medical problems you have and you will be seen at a pre-op assessment clinic for this purpose and to have a full medical check-up. All patients undergoing total elbow replacement surgery have a blood count and their biochemistry checked together with the blood inflammatory markers which are used to monitor the activity of rheumatoid arthritis and check up on infection. Some patients need their chest x-rays and ECGs done. Patients with rheumatoid arthritis need to have a neck x-ray prior to surgery as rheumatoid arthritis can cause instability in the cervical spine.
Patients can prepare themselves for surgery by understanding what is going to happen and by keeping as physically fit as possible prior to the surgery, you should therefore do your muscle exercises as much as you can within the limits of the fact that your elbow is obviously painful.
If you have rheumatoid arthritis your medical management should be optimised by the rheumatologist and the rheumatologist may also treat you with medications such as calcium and bisphosphonates to improve your bone density.
If you are a smoker you should stop. Smoking certainly increases the risk of a surgical complication following any procedure and total joint replacement is more likely to be problematic in a smoker.
Loosening in total elbow replacements is more common in people who have to use crutches or walking sticks because of lower limb problems. It is therefore routine that if you have a significant hip or knee problem this should be sorted out before any upper limb surgery is performed. Most patients come to this conclusion themselves anyway because the pain and disability caused by significant arthritis in the hip and knee is a more major problem for day to day life than the elbow.
Progress after total elbow replacement
Following the surgery the anaesthetist will have placed a drip in your arm. You may have a nerve block catheter which delivers local anaesthetic (similar to a dental anaesthetic). This is used to numb the pain in your arm so that you do not have to have such a strong general anaesthetic. Elbow replacement surgery is almost always carried out under a general anaesthetic. Although it is possible to numb the elbow using nerve blocks most patients with rheumatoid arthritis are unable to lie on their side for the three hours required. Following the surgery your skin will be closed with metal clips and there are two small suction drains. You will have a dressing on the skin which is simply placed on the skin and wrapped up with cotton wool. Large amounts of cotton wool are used because it is particularly important to pad the skin over the olecranon or point of the elbow. The idea of this is to reduce the risk of problems with the wound, pressure over the point of the elbow and the risk of blistering, particularly in patients with severe rheumatoid arthritis. The wool dressing has two small slabs of plaster of Paris to keep the whole arrangement in place.
This dressing is removed at around 48 hours post-surgery and a conventional stick-on dressing is applied. The patient then also has a lightweight plastic splint applied. The patient’s elbow is then mobilised initially with help from the physiotherapist. I prefer to see the patients myself when the splint has first been applied so that I can review things with the patient. There is some variability between patients in the stability in the elbow so sometimes it is best to keep the splint in place for a longer period of time. Most of the time at an early stage the patient can remove the splint for exercise purposes, initially two to three times per day. The physiotherapist will help to give you confidence to move the elbow under your own steam. You need to bear in mind that in most cases the patient gets a good range of flexion or bending in the elbow and usually the most troublesome stiffness is in achieving full extension in the joint.
The post-operative cast and the subsequent splint are therefore made with the elbow as straight as it will reasonably go. The other factor to bear in mind is that the key muscle and ligament repair is pulled on more when the elbow is flexed up than when it is extended. Regarding flexion therefore you can flex the elbow as much as it will go using your own muscle power, ie. try to get your hand up towards your mouth, but it is a mistake to push this movement too hard either by pushing hard with your other arm or by anyone else pushing it. When I see you I will try to give you an indication of how hard it is safe to push it in the early stages. The physiotherapist and yourself can push the elbow slightly more into extension. In this position the elbow may be slightly less stable but there is less risk of stressing the ligament repairs. It is best if the forearm is held in a neutral position whilst the elbow is being extended, ie. the palm of the hand is not flat down or facing upwards.
Most patients will leave hospital after about four days if they are local patients with some help at home and possibly a little longer if they come from a long distance or they live alone. Patients with rheumatoid arthritis may have difficulties caused by other upper limb problems such as painful shoulders. If you have painful shoulders or pain in the other elbow prior to surgery, if you let us know we can inject these joints whilst you are under the anaesthetic which often helps with post-operative progress. The clips are removed from the skin at about fourteen days. By this time you should be mobile around your house and taking the elbow splint on and off yourself to move the joint. After two weeks you can normally remove the splint when you are wide awake during the day. You may continue to wear it at night or when you are out and about for the first six weeks or so.
By six weeks post-operation you will normally have discarded the splint unless we advised you of any particular tendency to instability. To get back to driving your car, you will normally need to wait a good six weeks or so. Obviously if you have an automatic life is a little simpler, particularly if it was your left elbow which was replaced. You will probably have a clear idea in your mind when the elbow is strong enough to control your car. The best thing is to take your car to a quiet cul-de-sac and make sure that you have good control of it and you can do an emergency stop before you set off down the M6.
In the long term it is best to use the elbow for light day-to-day activities such as eating dressing and cooking. Heavy activities such as lots of gardening are best not done regularly. The new elbow will be good for light hobbies such as painting as these excellent examples show.
Total elbow replacement, in common with other joint replacements, is a major operation. Most of the time it is very successful in terms of pain relief particularly. The chances of success are increased by careful attention to detail both from the surgeon, other members of the team and the patient.