Hypermobility (joints)


Hypermobility, also known as double-jointedness, describes joints that stretch farther than normal. For example, some hypermobile people can bend their thumbs backwards to their wrists, bend their knee joints backwards, put their leg behind the head or perform other contortionist "tricks". It can affect one or more joints throughout the body.
Hypermobile joints are common and occur in about 10 to 25% of the population. It is usually not associated with any symptoms but a minority of people develop other conditions caused by their unstable joints; in such cases, it is known as hypermobility syndrome.
Until new diagnostic criteria were introduced, Hypermobility Syndrome was sometimes considered identical to Ehlers–Danlos syndrome hypermobile type/EDS Type 3. As no genetic test can identify or separate either conditions and because of the similarity of the diagnosis criteria and recommended treatments, many experts recommend they should be recognized as the same condition until further research is carried out.
In 2016 the diagnostic criteria for EDS Type 3 were re-written to be more restrictive, with the intent of narrowing the pool of EDS Type 3 patients in the hope of making it easier to identify a common genetic mutation, EDS Type 3 being the only EDS variant without a diagnostic DNA test. At the same time Hypermobility Syndrome was redefined as a hypermobility disorder that does not meet the diagnostic criteria for EDS Type 3 and renamed as Hypermobility Spectrum Disorder. The body of the article has not yet been rewritten to reflect this.

Signs and symptoms

People with Joint Hypermobility Syndrome may develop other conditions caused by their unstable joints. These conditions include:
Those with hypermobile joints are more likely to have fibromyalgia, mitral valve prolapse, and anxiety disorders such as panic disorder.

Causes

Hypermobility generally results from one or more of the following:
These abnormalities cause abnormal joint stress, meaning that the joints can wear out, leading to osteoarthritis.
The condition tends to run in families, suggesting a genetic basis for at least some forms of hypermobility. The term double jointed is often used to describe hypermobility; however, the name is a misnomer and should not be taken literally, as hypermobile joints are not doubled/extra in any sense.
Most people have hypermobility with no other symptoms. Approximately 5% of the healthy population have one or more hypermobile joints. However, people with "joint hypermobility syndrome" are subject to many difficulties. For example, their joints may be easily injured, be more prone to complete dislocation due to the weakly stabilized joint and they may develop problems from muscle fatigue. Hypermobility syndrome can lead to chronic pain or even disability in severe cases. Musical instrumentalists with hypermobile fingers may have difficulties when fingers collapse into the finger locking position. Or, conversely, they may display superior abilities due to their increased range of motion for fingering, such as in playing a violin or cello.
Hypermobility may be symptomatic of a serious medical condition, such as Stickler syndrome, Ehlers–Danlos syndrome, Marfan syndrome, Loeys–Dietz syndrome, rheumatoid arthritis, osteogenesis imperfecta, lupus, polio, Down syndrome, morquio syndrome, cleidocranial dysostosis or myotonia congenita.
Hypermobility has been associated with chronic fatigue syndrome and fibromyalgia. Hypermobility causes physical trauma. These conditions often, in turn, cause physical and/or emotional trauma and are possible triggers for conditions such as fibromyalgia.
Women with hypermobility may experience particular difficulties when pregnant. During pregnancy, the body releases certain hormones that alter ligament physiology, easing the stretching needed to accommodate fetal growth as well as the birthing process. The combination of hypermobility and pregnancy-related pelvic girdle during pregnancy can be debilitating. The pregnant woman with hypermobile joints will often be in significant pain as muscles and joints adapt to the pregnancy. Pain often inhibits such women from standing or walking during pregnancy. The pregnant patient may be forced to use a bedpan and/or a wheelchair during pregnancy and may experience permanent disability.
Symptoms of hypermobility include a dull but intense pain around the knee and ankle joints and the soles of the feet. The pain and discomfort affecting these body parts can be alleviated by using custom orthoses.

Syndromes

Hypermobility syndrome is generally considered to comprise hypermobility together with other symptoms, such as myalgia and arthralgia. It is relatively common among children and affects more females than males.
Current thinking suggests four causative factors:
Hypermobility can also be caused by connective tissue disorders, such as Ehlers–Danlos syndrome and Marfan syndrome. Joint hypermobility is a common symptom for both. EDS has numerous sub-types; most include hypermobility in some degree. When hypermobility is the main symptom, then EDS/hypermobility type is likely. People with EDS-HT suffer frequent joint dislocations and subluxations, with or without trauma, sometimes spontaneously. Commonly, hypermobility is dismissed by medical professionals as nonsignificant.

Ehlers–Danlos syndrome hypermobility type

Joint hypermobility is often correlated with hypermobile Ehlers–Danlos syndrome. Ehlers–Danlos syndrome is a genetic disorder caused by mutations or hereditary genes, but the genetic defect that produced hEDS is largely unknown. In conjunction with joint hypermobility, a common symptom for hEDS is smooth, velvety, and stretchy skin; a symptom largely unique to the syndrome. When diagnosing hEDS, the Beighton Criteria are used, but are not always able to distinguish between generalized hypermobility and hEDS.
Ehlers–Danlos hypermobility type can have severe musculoskeletal affects including:
Joint hypermobility syndrome shares symptoms with other conditions such as Marfan syndrome, Ehlers-Danlos Syndrome, and osteogenesis imperfecta. Experts in connective tissue disorders formally agreed that severe forms of Hypermobility Syndrome and mild forms of Ehlers-Danlos Syndrome Hypermobility Type are the same disorder.
Generalized hypermobility is a common feature in all these hereditary connective tissue disorders and many features overlap, but often features are present that enable differentiating these disorders.
The inheritance pattern of Ehlers-Danlos syndrome varies by type. The arthrochalasia, classic, hypermobility and vascular forms usually have an autosomal dominant pattern of inheritance. Autosomal dominant inheritance occurs when one copy of a gene in each cell is sufficient to cause a disorder. In some cases, an affected person inherits the mutation from one affected parent. Other cases result from new gene mutations. Such cases can occur in people with no history of the disorder in their family.
The dermatosparaxis and kyphoscoliosis types of EDS and some cases of the classic and hypermobility forms, are inherited in an autosomal recessive pattern. In autosomal recessive inheritance, two copies of the gene in each cell are altered. Most often, both parents of an individual with an autosomal recessive disorder are carriers of one copy of the altered gene but do not show signs and symptoms of the disorder.

Beighton criteria

As of July 2000, hypermobility was diagnosed using the Beighton criteria. In 2017, the criteria changed, but still involve the Beighton score. The Beighton criteria do not replace the Beighton score but instead use the previous score in conjunction with other symptoms and criteria. HMS is diagnosed in the presence of either two major criteria, one major and two minor criteria, or four minor criteria. The criteria are:

Major criteria

this has been edited

Minor criteria

The Beighton score is an edited version of the Carter/Wilkinson scoring system which was used for many years as an indicator of widespread hyper-mobility. Medical professionals varied in their interpretations of the results; some accepting as low as 1/9 and some 4/9 as a diagnosis of HMS. Therefore, it was incorporated, with clearer guidelines, into the Brighton Criteria. The Beighton score is measured by adding 1 point for each of the following:

Physical therapy

It is important that hypermobile individuals remain fit - even more so than the average individual - to prevent recurrent injuries. Regular exercise and exercise that is supervised by a physician and physical therapist can reduce symptoms because strong muscles increase dynamic joint stability. Low-impact exercise such as closed chain kinetic exercises are usually recommended as they are less likely to cause injury when compared to high-impact exercise or contact sports.
Heat and cold treatment can help temporarily to relieve the pain of aching joints and muscles but does not address the underlying problems.

Medication

Medication is not the primary treatment for hypermobility, but can be used as an adjunct treatment for related joint pain. NSAIDs are the primary medications of choice. Narcotics are not recommended for primary or long term treatment and are reserved for short term use after acute injury.

Lifestyle modification

For some people with hypermobility, lifestyle changes decrease symptom severity. In general, activity that increases pain is to be avoided. For example:
Hypermobile joints occur in about 10 to 25% of the population.