Pain & the Hypermobility Syndrome by Prof R Grahame CBE, MD, FRCP, FACP University College Hospital, LONDON.
When the Hypermobility Syndrome was first put on the medical map in 1967, it was defined as the presence of musculoskeletal symptoms (predominantly pain) occurring in otherwise healthy individuals. Thirty years down the line we now think that there are probably two types of hypermobility.
The first is a milder type occurring in people whose joints are just like everyone else's but which have the capacity to move more than most people's joints. The other, a more marked form, has features that suggest that it may be part of an inherited connective tissue disorder similar to the hypermobile form of the Ehlers-Danlos Syndrome, formerly called EDS III. It probably is EDS. At the present time we simply do not know for certain whether or not HMS is merely a less severe type of EDS III. Pain can occur in other forms. For the rest of this article, in order to avoid confusion, I will refer to it as one condition, the HMS/EDS. There are many people with joint hypermobility in the community who experience no (or very little) pain. Most of them probably do not even know that they are hypermobile at all. Then something happens, and they start getting pains for the first time in their lives. Usually unexpected exercise or a change of job or lifestyle provokes the onset of pain. When ever symptoms commence, and irrespective of the cause of the hypermobility, the term 'Hypermobility Syndrome' is used to describe the condition. Hypermobile people without pain are just called hypermobile people.
A little known fact is that hypermobility occurs in many individuals in a few joints only. It does not necessarily have to affect all one's joints. Even hypermobility in a single joint can cause pain and/or instability in that joint; the diagnosis is still Hypermobility Syndrome (HMS/EDS).
People are born hypermobile. It is in their genes. It is the way they are made. So how is it that people with hypermobility can be literally fine for decades, only to be laid low from widespread pain, often out of the blue, which may make its unwelcome appearance during childhood, adolescence, or adult life? To explain these curious and seemingly inexplicable happenings, we postulate that the affected person, in this case the hypermobile person, had an inbuilt weakness of her (it is usually a 'her' but not always) strength-providing collagen or similar protein. This weakness renders body tissues less robust and hence less able to stand up to the physical strains of everyday life. We can explain a lot of the pain that arises on the basis of a series of (often quite minor) injuries that occur whenever there is a mismatch between the physical demands on one hand, and the strength of the parts being asked to perform them on the other. There is a whole host of painful injuries that can result, ranging from dislocations to fractures, disc prolapse, ligament sprains, muscle strains, pulled tendons (like tennis elbow or plantar fasciitis), etc.- conditions that can happen to anyone, but which occur more easily in those with the HMS/EDS. If one only knew one's strength (or lack of it), one should be able, in theory at least, to stay within the safety margin and thereby protect oneself from injury. Up to a point this is so. Many people with the HMS/EDS are able to modify their lifestyle and do just that. Others find it more difficult.
A joint that is beginning to wear starts to lose its cartilage or gristle, which is essential for the smooth movement between the adjoining bones. This wear heralds the onset of osteoarthritis, a condition painful in its own right. It is a very common form of arthritis in middle and old age, and one to which hypermobile people seem to be prone, in many cases at an early age. It is important to establish as far as possible to what extent the pain is due to trauma/overuse or to early onset osteoarthritis, as the treatment is very different. The emphasis with the former is on prevention, while with the latter it is on treatment by one form or another.
However, neither susceptibility to injury or overuse (repetitive injury), nor osteoarthritis, explains all the pain that is felt in the HMS/EDS. There is more to it than that. And here we get into a rather grey area, where there is more speculation than fact.
Let us try to piece the jigsaw together. Pain is something we feel. Even if it has a physical cause, as it undoubtedly has in the HMS/EDS, it is still a subjective experience. It is often accompanied by an intense sense of exhaustion. the severity of the pain we feel is greatly influenced by our state of mind. If we are upset or agitated it tends to increase. If we are content, relaxed or just happy it tends to diminish. The HMS/EDS people are often in the former category, and for good reason! Lack of understanding of the condition is widespread, and this, coupled with failure to receive adequate treatment for relief of symptoms, leads to frustration, resentment, anger (and lots more emotions which I could list but readers know them all only too well!) and, ultimately depression. These emotional influences can amplify pain, but they do not cause it.
Another piece of the jigsaw is a mysterious condition called fibromyalgia. This condition causes widespread chronic pain in muscles and is identified by the finding of multiple 'tender points' at specific sites in the body. For years the debate has raged as to whether it is a physical disease affecting the muscles, or whether it is an emotional disorder. The prevailing view is that it is probably some form of distress signal that can arise in people with a number of different and unrelated conditions. How this relates to hypermobility is that it has been shown that hypermobility and fibromyalgia occur together in the same person more often than one would expect on the basis of a chance happening. It does not mean that they are part of the same condition. It would, indeed be very unlikely that what is clearly an acquired disorder (fibromyalgia) could be an integral part of what is clearly a genetic one (HMS/EDS). More likely, the fibromyalgia should be regarded as a signal emanating from a distressed HMS/EDS person. But fibromyalgia occurs only uncommonly in the HMS/EDS. We must look further afield.
It seems quite likely that there may be a totally different explanation for the burden of pain borne by people with the HMS/EDS.
Here are two clues:
The first clue relates to the sense called proprioception, which means knowing where parts of one's body are in space. If you close your eyes and somebody bends your finger for you or picks your arm up, you know immediately how far your finger is bent or where your arm now is. That is because you have good proprioception. Scientists have shown that people with the HMS/EDS are not quite as good as other people in knowing exactly where their fingers or arms etc are in space. This could lead to a further increase in the risk of injury.
The second clue is the discovery that patients with the HMS/EDS for some
reason do not appear to experience the full anaesthetic affect of lignocaine injections when these are given for dental purposes, minor surgery or for epidural anaesthesia (I wonder how many readers are nodding their heads as they read this!).
At the present time we do not know quite what either of these clues means or whether they relate to one another. But they do suggest that people with the HMS/EDS, in addition to their proneness to injury, dislocation and osteoarthritis, may also have a fault in the way their pain signals are picked up for onward transmission to the brain, where they reach consciousness. Research work is in progress to try to sort out this enigma. Much more needs to be done. Watch this space!
Readers will know that many conventional methods of treatment, of the kind offered for rheumatic complaints in general, are not particularly helpful in the HMS/EDS. Physiotherapy still carries the best prospect for pain relief, and it is encouraging that more physiotherapists are training in methods that are helpful in this condition. Another noteworthy development is the network of units throughout the country that are offering pain management programmes, an approach which has been shown to be beneficial in the HMS/EDS where intractable pain is present.
Source: http://www.hypermobility.org/
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