| GREAT ORMOND STREET APPROACH TO ARTHROGRYPOSIS. MR JOHN FIXSEN Mchir FRCS The Arthrogryposis Group International Conference 1993 At Great Ormond Street a child with arthrogryposis will probably not come directly to me but to one of my neurological or paediatric colleagues and I will be called in as one of the team of 'experts' to try and advise what might be done orthopaedically. I may also get asked by orthopaedic colleagues to take on the management of a child with more established deformities. Because this condition is fairly rare the majority of orthopaedic surgeons have little or no specialised knowledge about it unless they're in a major centre seeing a large number of children. One of the hardest things is to establish a diagnosis. Arthrogryposis isn't really a diagnosis, it's a description. There are at least a hundred and fifty possible things that can produce a child who has arthrogrypotic features. So although as parents you want to know what is wrong with your child, what the prognosis is going to be, what the treatment is going to be, we as doctors find that very difficult. I krmw there's great frustration about that - that we have to hedge and prevaricate when in fact you want hard facts. I am a great believer that it's much better to be honest and say I don't know than throw out possibilities that may turn out to be too optimistic or too pessimistic. Sadly I see both sides of that: there are people who have been told that their children will never walk and possibly not survive and there they are, able to walk and do things. Vice versa, they may be given a very optimistic prognosis but the child has one of the conditions in which the muscles are very weak and still at the age of three can't sit up. Then you have the problem of somebody who has been given too optimistic a prognosis too early on. It takes time to sort out what may be the cause of this extraordinary condition. Arthrogryposis means 'curved joints'. Sir Wilfred Sheldon from Gt Ormond Street described it as amyoplasia congenita in 1932 Myodystrophia foetalis deformans is another descriptive diagnosis that really doesn't mean anything more than "curved joints". Otto, a German, is credited with the first description in Europe in 1841 of this condition. Basically the child will have multiple rigid joint deformities. The muscles are affected but you don't know when you first see the child, in what way. What is apparent is that there is too little muscle. The ratio of muscle to tendon is reversed. Some muscles are apparently quite normal; others are missing. The children have normal sensation and that's terribly important as there are a number of other conditions that may look very similar but have a disturbance of sensation. Most of us think of sensation as being able to feel something but sensation of where you are in space, proprioception - what your joints are doing - deep pain sensation - these sort of things are also very important and undoubtedly in terms of moving about, it's important to understand where one's body is in space. In some conditions that perception is missing and that greatly impairs the ability to walk or stabilise yourself. Again it has to be present at birth; it's not something that is acquired later. Ruth Wynne-Davies, an orthopaedic geneticist, did a survey in 1981 on the incidence of arthrogryposis in this country. Edinburgh had at that time the most complete birth register in this country, all 56,000 births had been registered with only on case of arthrogryposis. At that time there was a very contrasting figure from Helsinki with an apparently very high incidence of three per ten thousand. One of the things that's come out of the research programme, so kindly funded by this Group, is that we're getting much clearer about these figures. One per ten thousand is perhaps nearer the right figure. The main problem is the underlying cause of arthrogryposis. Ruth Wynne-Davies suggested that it was a disease of early pregnancy associated with one or more unfavourable intra-uterine factors. Certainly there are a number ofnfluences such as neurologic or muscle problems, connective tissue problems, the problem of the foetus being crowded in the womb producing foetal immobility. Almost all patients with this condition seem to have an inability to move normally within the womb and this is certainly one of the factors producing a child with arthrogrypotic features. Muscle defects Nerve defects Connective Tissue Foetal Crowding Lead to Limitation of foetal joint movement Results in Features of arthrogryposis To try to establish which of the hundred and fifty possible causes led to the child's features the following investigations should be considered:- Chromosome studies Collagen Biochemistry Creatine Phosphokinase level - to exclude muscular dystrophies Electromyography and nerve conduction studies Muscle biopsy X-ray of spine, pelvis and limbs involved C.T.head scan They are in fact largely not orthopaedic. Chromosomes tests will be done by the genetics department, collagen biochemistry by the people concerned with collagen, creatine phospho-kinase, the muscle enzyme test, by the bio-chemical laboratory, EMG's by the neuro-physiologist, who may also ask for a muscle and nerve biopsy. The neck and the whole spine should be looked at and also a CT scan of the head. Nowadays, if the facilities are available, magnetic resonance imaging is the best way of imaging the central nervous system. This is frequently used in the Gt.Ormond Street neurology department to try and look at the central nervous system and the spinal cord to see where the problem is and what is happening to it. In neurological terms: spina bifida may produce very classic arthrogrypotic appearances; myelodysplasia, sacral agenesis, spinal muscular atrophy; foetal neuropathy are all things that can produce a baby with arthrogrypotic-like features. The treatments and the outcomes can be very variable. As a general rule in arthrogryposis if the muscles are particularly weak or hypotonic the orthopaedic surgeon's job is much more difficult and surgery much less successful. What do we try and do? Obviously what we would like to do is to achieve the maximum function for the patient. Independent mobility, whether it's walking independently, with aids or in a chair, is tremendously important for any sort of independent life. This is very high on our list of priorities and the real key to independent mobility is a stable trunk. It's important to feed and toilet yourself if you possibly can, without having to ask for help. Jie occupational therapists have been tremendously helpful in developing aids and special tools to encourage this. Finally, we would like everybody to have the ability to gain employment. This means ensuring that you have a good education as well as your medical treatment. How do we start? Everybody agrees that it is worth trying to get as much movement out of the Joints as you can as soon as possible. Occasionally, people 'throw in the sponge' straight away. I had somebody recently ring me up and say, "Really I don't think there's any point doing physiotherapy or splintage because the joints are so rigid." I agree there's no use 'banging your head against a brick wall' if you're getting nowhere but one can be very surprised sometimes how an apparently very rigid deformity in the first few weeks of life will respond to gentle stretching and splintage. In the hand, where we were rather inactive about ten to fifteen years ago, we are now tremendously impressed with how useful early splintage can be. This is largely splinting at night because you don't want to impede the child's exploration of the world around it by holding it in splints during the day. Muscle imbalance is rarely important. For these stiff, rigid joints, muscle transfer is rarely indicated. Recurring deformities can be a real problem. You go through a long operation, a long period of plaster and splintage only to find that two or three years later the knee or the foot goes back to where it was before. We do not really understand why this happens. The deformities seem to recur in the soft tissue rather than the bone - at least primarily. They tend to be around the joints and so our surgery tends to be concentrated around the joints and basically it's rather inadvisable to resort to bony surgery early on in the growing child because then you find that the bone just grows in an abnormal bend and you have to correct your previous corrective operation. Personally, I try to avoid taking the easy option of correcting the bone because that may add a second deformity to the first. Joint movement, by definition is always limited, though in simple terms you want to establish what range is there. Early physiotherapy is SO important because so often there IS a greater range than initially there appears to be. I've had no evidence of gaining a range and then it disappearing again provided the movement is maintained by exercise and splintage. When you've got that range, you've got to decide where is the most useful place to put it and that is where surgery comes in. You may increase the arc of movement during the surgery but I never promise to do that. If you have a knee that bends from 70 to 90 degrees, it may be better if that range is from about 15 to 35 degrees and that's often what we do. We may with luck gain some movement but we certainly can't guarantee to do that. The concept of putting the arc of movement in a position which is most useful for the child to walk, is a very important in the management of these children's deformities. These children vary tremendously in the time they take to get trunk stability. It is not worth rushing into a lot of surgery until you're sure the child's going to be able to use it properly. I get a small number of patients, who have early surgery for deformities usually in the lower limb, before they are able to make use of that surgery. They then relapse to where they were before and have to sta^ll over again when they're ready for it. So although there's a great desire to rush in and do something, I think it pays to wait until the child is ready for their surgery. However, in the lower limb this tends to be much earlier than in the upper limb. With the upper limb it's very difficult to know what to do early on. We tend to only operate after a very careful, functional assessment. For example if the arm needs to be extended to use crutches it's not much use doing an operation which allows you to bend your arm but not extend it. This sounds very obvious but it has been done and I suspect will continue to be done if people don't think of the upper limb as a functional whole in this condition. Again with really weak muscles, you do have to be careful. Surgery tends to be dividing or lengthening muscles. We never strengthen the muscles by surgery and you do have to be sure that your surgery is going to be useful. PHOTO This young man didn't really get any trunk balance until he was about 18 months so we did very little apart from stretch his legs and get what movement we could. However, once he got his trunk balance, we straightened out his legs. Then the question was, Is it useful to do anything for his upper limbs? He's got particularly weak muscles and defective shoulder musculature and yet he manages his crutches; he's very independent on his own, he's quite good at self-care and he can flex up one arm with the other arm in the very characteristic manner of these patients. Although we did offer the possibility of giving him power to bend one elbow, he has in fact elected to stay as he is. To use crutches you must have extensible arms and not jeopardise that in order to get flexion. When talking about orthoses, a lot of our patients still use what I would call very old-fashioned callipers. A lot of our patients have tried moulded callipers but go back to the older style callipers because they allow more freedom of movement and they're more adjustable. However, everybody knows how long it sometimes takes to get a new set of callipers moulded. I would however like to see a more modern form of orthosis. Rarely is anything done to the shoulder and very little is done with the elbow, but they must always be considered together. The triceps can be lengthened to improve the passive range of flexion, because in themselves they are a powerful extensor. If the elbow is fixed in extension then you can stretch it and sometimes lengthen the triceps without losing significant extensor power. When considering flexing the elbow, the passive range can be increased by a release which usually works very well and then there are various ways of obtaining motor power. Flexorplasty is one operation for example but often it can't be done because there isn't enough power and it can affect the fingers. However, with this operation you can get very good power for flexion but lose extension. Pectralis major transfer is another possibility for the flexor power. With shoulders you can do a sot tissue release of adduction and internal rotation or an external rotation osteotomy but ctf^v if it's going to be of value. Stretching in infancy is beneficial and can increase the range of movement. The wrist tends to bend and go into ulnar deviation. If the hand and fingers are stiff, it's important to know how the person uses them. They can be like hooks and if you make the wrist straight they can be less functional. The benefits of any operational procedures on the wrists tend to be only temporary and the deformity recurs. Fixing the wrist and hand straight is probably the only reliable operation and is carried out around adolescence if the child wants it done and then only on someone who has good mobile fingers. Even so the wrists should not be fully straightened but left slightly flexed so they can use the fingers really well. Fingers are rarely helped by surgery. Sometimes the thumb is brought out of the palm; sometimes that's the best place to use it so it is left there. SUMMARY Basically surgery is much more applicable to the lower limb than to the upper limb. There are some instances where it can be helpful in the upper limb but only with very careful assessment of the individual's needs and abilities. Arthrogryposis is a non-progressive condition. The patients have sensation and avoid some of the problems of neurological conditions with abnormal sensations. Best of all patients with arthrogryposis are always marvellous to treat because however inefficient our attempts at surgery, they always do their best and I'm always amazed at how well children do with very often, to our minds, rather inadequate surgery. We only change the foot shape or the range of movement at the knee or the elbow and yet they go ahead, go to school, manoeuvre wheelchairs and do all sorts of things. Children with arthrogryposis are very rewarding to treat. QUESTION: Very often these days you hear of replacement joints - plastic joints. You've been talking about fingers and stiff wrists and that sort of thing. Has anything been developed to cope with that sort of scenario? JF: The trouble with all the replacement joints is that they all come loose and they're all liable to breakage. Certainly in children, except those with juvenile chronic arthritis, people have tried not to use any sort of joint replacement. The real problem being that it may work for a while but then it would usually have to be removed. Far and away the best experience of hand joint replacement is in rheumatoid arthritis; smalt, plastic joints are put into the metacarpophalangeal joints. Although patients ask for a wrist replacement, none of them work terribly well. In arthrogryposis the real trouble is the lack of muscle or the thinness of the muscle to actually work these joints and I think most of us feel that you would not get a useful increase in movement by trying to replace the joints by an artificial one. Also in the long term there'd be problems of the joint falling to pieces, breaking, possibly getting infected and having to be taken out. On the whole, although I have done one or two adult joint replacements in arthrogrypotics, I've never undertaken it in children. In the few adults with arthrogryposis where I have carried out hip ^placement, the problem has been moving the joint because they still have a muscle deficiency. It has helped the pain and that's good, but they haven't gained the sort of movement they were hoping for because their muscles are stiff; they don't have the range of muscle movement to move the joint. QUESTION: Regarding that muscle problem, is there anything that one can do to improve it generally? JF Clearly, what muscles you've got you must keep moving; that's one thing. You can't do anything about the fact that there is often far too much tendon and far too little muscle. The ideal would be to put a new muscle in but this hasn't really taken off as far as I know. It's not as if you've got a normal muscle that's been damaged; it is in fact very defective muscle. You've got to make the best use of what you've got, we can't magically build it up: you must keep what range you have. That's why it's always difficult if a person with arthrogryposis injures themselves, it's much harder to rehabilitate afterwards. QUESTION: With extended elbows, which elbow would you try to put in the flexion position the dominant side or the other side? and would you try to have it only flexed in stiff flexion or would you try to get an even more flexible elbow with some muscle power? JF I'm not sure I can give you a straight answer. I'm extremely reliant on our physiotherapists and occupational therapists' assessment Basically, what we've come round to doing is to offer people who want it the ability to flex one arm. Then assess their activities of daily living and try and decide which one would be better to operate on. Is it more important to get the dominant or the non-dominant hand moving to the mouth? Now it might automatically seem it's the dominant one you want to get to the mouth first but it's not always the case for certain reasons. The child may find that it absolutely needs to have the hand extended on the dominant side for certain activities of daily life. What I then do is provide them with passive flexion by the classical posterior release operation. Provided that's done before there's too much bony abnormality in the elbow I've usually found that's very successful. Obviously there are some patients who have a virtually fixed elbow and you can't do that. It does seem that the elbow joints remain reasonably congruous and able to bend if the extensor is released via a normal release. So I give them the passive flexion but I don't immediately give them the motive power because many people use the extended arm to bend the other one up. Some of them say, Well, I'd rather lose passive flexion but retain some active extension than risk losing my power to actively extend. So it's done very carefully and slowly. In fact for a short while I was encouraged by Peter Williams from Australia and did the triceps transfer but thought I was doing it wrong. I got marvellous flexion yet no extension unfortunately and it tended to get more and more flexed. I was therefore pleased with his long term clinical follow-up in which he pointed out the same problem and he is now much less keen on that as a transfer. You can't afford to lose active extension. ^b In a way I don't think I've answered your question but I think the approach has to be very individual with each patient. If our patients come from a long way away we will sometimes admit the patient for an assessment before deciding to do anything. Once done, it's rather difficult to undo. QUESTION: - I'm an OT. In a newbom baby should I stretch to a functional position or should I try and keep a more normal newborn-baby-position and how do I know if I'm likely to damage the joints by stretching them further than they realty want to go? JF Basically yes, you mustn't cause damage by being over-zealous with your stretching. I agree that can be difficult to judge. Usually I would suggest that you just try to get what range there is and maintain that. But it's tremendously variable. For each joint you just try and establish the range that is available with conservative i.e. non-surgical methods of treatment. So once you've got that established I wouldn't go on pushing and pushing. Certainly if there is any sign of pain or swelling, then stop perhaps for a day or so, but it is difficult to judge. You cannot tell somebody how hard to push. I wouldn't go for a set range because they're just so variable. Sometimes I've written in the notes: "Please stretch, but I think it's unlikely that you'll gain very much say in the knee." Then a couple of weeks later it's totally wrong, the knee has corrected beautifully but the foot which I thought would be quite easy, hasn't moved an inch! You can't lay down hard and fast rules. QUESTION: Obviously you do hand surgery with great caution. Would you ever consider splinting prior to doing hand surgery, say if you were looking at getting the wrist to better extension to perhaps try a splint a little prior to surgery? JF As I've said, my old chief was not keen on splinting the hand. I think he was worried that it would prevent the child developing these amazing skills they have of using their hands as they are, but I've become a convert to hand splintage in the first few months of life. Modem materials mould into splints very easily; they can wear them particularly at night and for some of the day. I have seen badly deformed hands come out into a much more usable position and I would certainly be very much in favour of splintage early on. Then when the child was at the stage of exploring the world around it, you don't want the hand covered up by a big clumsy splint. These children have got normal sensation; they've got this amazing ability to adapt what they've got and use it. You don't want to impair their learning, so we tend not to splint during the day but at night. So in the upper limb, particularly the hand and wrist, I'm a great convert to splints now, it produces a much better position if the hands are splinted. QUESTION: Do you know what was attributed to the epidemic in the 1960^? JF Ruth Wynn-Davies's study Ic^ed at the incidence of cases in this country, America and Australia. The interesting thing is that Australia has a rather higher incidence of arthrogryposis and I think in all of her groups there seemed to be an increase in the number of reported cases at the end of the Sixties as if there had been an epidemic. There has always been an interest in the aetiology as to whether it IS due to some intra- uterine infection similar to the one vets know as akabane virus that produces a very similar type of deformity in cattle, sheep and horses, so it seemed to fit in. It looked as though there were a lot of children at the end of the Sixties born with this condition and then it seemed to settle down again into the more normal expected incidence. The whole problem of incidence is when you're talking about a descriptive term. It's very easy for one person to call this arthrogryposis and for another one to say, No it's not, it's something else. So I think with the variation of what the reporters considered arthrogryposis, there was a suggestion there might have been an intra-uterine infection. PROF ROBINSON: A number of epidemiologists have re-visited that work and felt that it is possibly an artefact of the case collection method. QUESTION: Going back to splinting: If the child wasn't splinted on the wrists and fingers at an early age, yet the child has become very useful with his hands as he's got older, is it wise to start splinting then? Is it recommended and if it is, is it effective? JF I think as I've said in the past, we didn't use splintage when I started at Great Ormond Street in the early Seventies. I'd worked there with Mr Lloyd-Roberts then and we were rather sceptical about the value of splintage, probably because we didn't have as good materials as we have nowadays: splints were clumsy, perhaps the attitude to them was different. But all I can say is that if I see a child NOW with significant deformities in the hands and wrists shortly after birth, I would normally try and splint them to get a greater range of mobility and I don't think we have lost function by doing that. If you're getting absolutely nowhere with splinting, then I don't think one should go one trying to push something that won't go and we have to accept that that's where the hand and wrist is and see how the child manages - and a lot of them manage extremely well. Certainly, once they've got established deformities, it's very difficult to alter those. It's often better to leave them to function with the fingers in the deformed position. On the whole, with our present knowledge, I'd recommend splintage, specially if it was seen to be making an improvement. QUESTION: What about the serial splinting in order to move the arc of motion? JF. It has been known for a long time that if you splint a joint at the limit of its range so that the muscles are on stretch the whole time, 24 hours a day for a period of time, when the splint is removed, you can move the range further. With the knee it's extremely difficult, in fact sometimes dangerous, to put a knee that's significantly flexed straight out into extension. You often have to go through a period of serial splintage, gradually getting the knee out as far as will go. Blood vessels and nerves can only be stretched so far and if you go too far, you'll damage them, you can even damage bones. Taking things a step further, I'm sure that the Ilizarov device is going to be used or considered more. It has the potential to both stretch and alter angulation and I'm sure people are beginning to consider it as an alternative to surgically correcting deformities. Serial splinting is part of the armamentarium to try and get a joint out to its maximum extension or y^o its best position. QUESTION: Do you know of anyone who is experimenting with growth factors to increase the muscle bulk? JF The simple answer is, No. Growth factor to make you taller, yes. There is a lot of interest in growth hormone in considering increasing children's height but not specifically to make the muscles grow. | |
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