Joint hypermobility (JHM), or the movement of certain joints beyond their normal range of movement occurs due to excess laxity of the ligaments that bind a bone to another bone in a joint. Such hyperlaxity of ligaments may arise from a variety of underlying causes and may be associated with many syndromes or disorders. Joint hypermobility is not uncommon, but often missed in clinical examinations. Joint hypermobility by itself is not a disease and in most people does not cause any symptoms. It may be associated with focal, regional or widespread mechanical injury. It may also be advantageous to professionals like ballet dancers. However, the finding of JHM is an important sign that can guide one's suspicion to the presence of a hereditary disorder of connective tissue.
Joint hypermobility syndrome/ H-EDS JHM + Symptoms = JHS
When there are musculoskeletal symptoms attributable to the joint hypermobility, the condition is called Joint Hypermobility Syndrome (JHS). Often symptoms in organs other than the joint structures are present as well. The same symptoms with a higher severity, involving recurrent joint dislocations, may often lead to a diagnosis of Hypermobility Type Ehlers-Danlos Syndrome (HEDS), previous called EDS type 3. It appears that the underlying mechanism of injury and disease is the same and the distinction between the two conditions is only a subjective clinical view of the diagnosing doctor. There is also a considerable difference in the severity of symptoms from patient to patient for both the conditions. Therefore, many eminent authorities believe that the two diseases are the same, and there is a spectrum or range of clinical severity, possibly arising from different kinds of genetic variations in the collagen and other connective tissue proteins. With advances in genetic medicine, we may have the answers soon. Read about the terminology and different names used in for joint hypermobility syndrome here.
Both JHS and HEDS are hereditary (genetic) disorders of connective tissue characterized by joint laxity and hypermobility. In both these conditions, the defective genes affect the collagen synthesis involving the joints and almost every bodily system. The inheritance pattern of the genetic defect is autosomal dominant, meaning that a child will have a 50% chance of inheriting it from a parent. Collagen is a major protein in our body that is present in skin, menisci, tendons, ligaments, cartilage, bones, blood vessels, the gut, intervertebral discs, eyes and in gums. Therefore, the collagen abnormality that leads to hypermobility also leads to a number of disorders throughout the body and affects many different body systems in JHS/H-EDS.
Reliable prevalence data is lacking in India, but studies estimate that the prevalence in Asian Indians is more than in the Western countries [1,2]. Women are more affected than men. Many studies have used different diagnostic criteria leading to variability in their results. The study carried out by Hasija et al (2008), found the presence of JHM in 59% children out of 829 3-19 year old Indian children with 26% of the JHM children having musculoskeletal pain, while only 17.7% children without JHM has musculoskeletal pain. They also found a correlation between the presence of JHM with malnutrition . Most studies indicate that the number of people with JHS (since it is a spectrum, the severity of symptoms will vary) might well be over a million.
Pain is a consistent feature. It may be acute, musculoskeletal in nature or chronic, neuropathic in nature. The pain may be localized or widespread. The picture may look like Chronic Fatigue Syndrome or Fibromyalgia, and indeed, these two conditions occur more in JHS patients. As a direct effect of the disorder, there may be chronic joint pains, spinal problems, various ailments throughout the body and a variety of joint and soft tissue problems. The increased and abnormal range of movement damages the joint structures and early onset osteoarthritis is often present. There is often muscle stiffness and weakness. The person may have a serious fatigue problem and sleep related issues. The defective collagen possibly is responsible for a plethora of symptoms involving almost all the body in a JHS patient. There may be gastroesophageal reflux, easily bruised skin, irritable bowel syndrome, asthma, uterine or rectal prolapse, nerve entrapment, problems with regulation of blood pressure, etc. Since these symptoms are often difficult to correlate clinically or using any laboratory test to any abnormality in the body or genetic abnormality, the actual underlying disease is often not diagnosed.
Effects on Personal and Social Life
There may be loss of job, difficulty in doing activities of daily life, difficulty in childcare and consequent psychological effects. The person may be unable to do a lot of things, but may not look disabled (like a person with a broken arm in a plaster cast, for example) - giving rise to invisible disability. The doctors, family and friends may not take the complaints of pain seriously enough because there is no apparent cause and therefore, no diagnosis. The chronic pain, invisible disabilities and lack of understanding from others seriously affects a person's psychology, career, and social and personal lives in general. There is also sleep disturbance which along with the chronic pain may lead to cognitive dysfunction - memory problems, difficulties in studies and processing complex information, etc. There may be anxiety, heightened pain perception and poor balance as a part of the disease.
The diagnosis of JHS is a clinical one, there are no laboratory tests of blood, or genetic tests that can be used to diagnose JHS. A constellation of signs and symptoms point to the presence of JHS. There are many ways to assess laxity of ligaments and there are specific assessment methods for individual joints.
Assessment of Joint Hypermobility (JHM)
JHM is measured by the ability of a joint to perform certain movements or a number of manoeuvres. There are two popular scales: the Beighton 9-point scale (Beighton et al 1973) and the Rotes-Querol Scale (Bulbena et al 1992).
Diagnosis of Joint Hypermobility Syndrome
Clinically, the most useful diagnostic criteria at present is the one proposed by The Special Interest Group devoted to inheritable connective tissue disorders of the British Society for Rheumatology in Brighton in 1999, known as the Brighton Criteria . It incorporates the Beighton score of hypermobility assessment.
Management There is no "cure" for JHS. However, the aim of the treatment options are to address the pain issues, prevent future injuries, heal the present injuries, strengthen the muscles and improve posture and balance. Education and lifestyle advice are important components of the medical advice. Significant behavior modification is often required. Taping, bracing and pain medication are often used for pain management. Physiotherapy is the mainstay of management. It can make a significant difference in a person's life to get a good physical therapy regime.
Infographic on the clinical spectrum of JHS/HEDS/EDS-HT
References  Harris H, Joseph J. Variation in extension of the metacarpophalangeal and interphalangeal joints of the thumb. J Bone Joint Surg Br . 1949;31-B:547-559.  Wordsworth P, Ogilvie D, Smith R, Sykes B. Joint mobility with particular reference to racial variation and inherited connective tissue disorders. Br J Rheumatol . 1987;26:9-12.  Hasija RP, Khubchandani RP, Shenoi S. Joint hypermobility in Indian children. Clin Exp Rheumatol. 2008; 26(1):146–150.  Grahame R, Bird HA, Child A, et al. The revised (Brighton 1998) criteria for the diagnosis of benign joint hypermobility syndrome (BJHS). J Rheumatol . 2000;27:1777-1779.