Friday, October 11, 2013
Hidden Disabilities: Hypermobility
here is my first post on Hidden Disabilities, so folks can learn that although though one may not be able to 'observe' the disability, the disability can be observed in clinical exams,blood tests and scans. Hypermobility syndrome was recognized as a distinct pathology by Kirk et al1 in 1967. Since then, the syndrome has been identified by a variety of names: “hypermobility syndrome (HMS),”2–9 “joint hypermobility syndrome,”10–13 “hypermobile joint syndrome,”14 and “benign hypermobile joint syndrome.”15,16 Other reports do not recognize this disorder as a syndrome, but refer to the manifestations of joint hyperlaxity, joint hypermobility, or articular hypermobility. In the International Nosology of Heritable Disorders of Connective Tissue, Beighton et al17 identified this syndrome as “familial articular hypermobility syndrome.” Beighton et al excluded genetic diseases that include joint hypermobility as an associated finding, such as Ehlers-Danlos syndrome, osteogenesis imperfecta, and Marfan syndrome. Despite the proliferation of names, HMS has been given relatively little attention in the literature. Most reports are in the rheumatology literature, with virtually none in the orthopedic or physical therapy literature. This lack of reports may be due to several reasons. First, individuals with HMS are often seen by orthopedic physicians and physical therapists as a result of an acute or chronic disorder, which may be treated without the health care provider acknowledging the underlying HMS. Second, the diagnostic criteria for HMS are not well-defined and have not been consistent among research reports.8,18–20 In particular, patients with HMS lack laboratory or radiological findings that could identify HMS, unlike many other rheumatologic or orthopedic conditions. The diagnosis, therefore, is frequently made through exclusion of other disorders. Third, individuals with HMS often do not have the decreased mobility seen with many chronic conditions,4 nor do they always have the inflammation seen with many acute conditions. Finally, because HMS lacks a definitive pharmacological or surgical treatment, physicians may have perceived little benefit in its diagnosis. Patients with HMS often have complaints that are frequently diffuse, chronic, and inconsistent with observed pathology. These individuals may be improperly identified as having hypochondria, as malingering, or as having nonspecific chronic pain, without further investigation into the source of their complaints.11,21 Individuals with HMS may not get a diagnosis, or they might be misdiagnosed.22 Failure to recognize the underlying HMS may lead to unnecessary or inappropriate diagnostic studies, surgical procedures, and patient management,23 especially for children.24 Some reports of HMS describe it as “benign” when compared with the serious connective tissue diseases that have hypermobility as one of their signs.15,16,25,26 Hypermobility syndrome has also been described as representing the upper end of the normal distribution for ligamentous laxity,27,28 with no greater incidence of pain or injury.29,30 Some authors25,31–34 have even proposed that hypermobility may be an asset in certain sports or professions. The mobility present in people with HMS, however, is considered beyond the normal range by most researchers,6 with repeated reports describing increased incidence of pain and associated disorders (Tab. 1). A goal of this update is to increase awareness, understanding, and discussion of HMS through examination of the prevalence, diagnosis, clinical presentation, and pathophysiology. Although physical therapy for people with HMS has been recommended by many authors,2,3,11,26,35 there are no published reports regarding the efficacy of physical therapy or any other treatment for individuals with HMS. Hopefully, increased recognition will lead to increased research about this disorder. Chronic pain in people with HMS is not always associated with inflammation. Some authors2,38 recommend the use of nonsteroidal anti-inflammatory medications, whereas other authors11,80 report that the use of these drugs is neither practical nor effective. Directions for Future Research Many unanswered questions remain regarding HMS. Prospective studies of physical therapist patients are needed to determine the percentage of patients with HMS. Such studies could determine, for example, how many patients with HMS have musculoskeletal problems versus nerve compression disorders. Although many authors recommend exercise for these patients, few have any data on which to base that recommendation. Moderate- and low-impact strengthening exercises, cardiovascular exercise for weight control, and stretching of muscles rather than joints seem theoretically sound recommendations, but the assumptions on which these recommendations are based must be tested. Given the predisposition of patients with HMS for cumulative trauma injuries, studies are needed to determine how much exercise is appropriate for these individuals. The use of orthotic devices, braces, and taping for patients with HMS also warrants further research.