Hypermobility (joints)

Those with hypermobile joints are more likely to have ADHD, autism, dyspraxia, fibromyalgia, hereditary connective tissue disorders, mitral valve prolapse, and anxiety disorders such as panic disorder.[8][9][10][2][11]

Hypermobile metacarpo-phalangeal joints

Hyperextension of the thumb

Hyperextension of the hand

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:

• The shape of the ends of the bones—Some joints normally have a large range of movement, such as the shoulder and hip. Both are ball-and-socket joints. If a shallow rather than a deep socket is inherited, a relatively large range of movement will be possible. If the socket is particularly shallow, then the joint may dislocate easily.
• Protein deficiency or hormone problems—Ligaments are made up of several types of protein fibre. These proteins include elastin, which gives elasticity and which may be altered in some people. Female sex hormones alter collagen proteins. Women are generally more supple just before a period and even more so in the latter stages of pregnancy, because of a hormone called relaxin that allows the pelvis to expand so the head of the baby can pass. Joint mobility differs by race, which may reflect differences in collagen protein structure. People from the Indian sub-continent, for example, often have more supple hands than Caucasians.[14]
• Muscle tone—The tone of muscles is controlled by the nervous system, and influences range of movement. Special techniques can change muscle tone and increase flexibility. Yoga, for example, can help to relax muscles and make the joints more supple. However, yoga is not recommended by most medical professionals for people with Joint Hypermobility Syndrome, due to the likelihood of damage to the joints. Gymnasts and athletes can sometimes acquire hypermobility in some joints through activity.
• Proprioception—Compromised ability to detect exact joint/body position with closed eyes, may lead to overstretching and hypermobile joints.[15]

Hypermobility can also be caused by connective tissue disorders, such as Ehlers–Danlos syndrome (EDS) 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 experience frequent joint dislocations and subluxations (partial/incomplete dislocations), with or without trauma, sometimes spontaneously. Commonly, hypermobility is dismissed by medical professionals as nonsignificant.[16]

Joint hypermobility is often correlated with hypermobile Ehlers–Danlos syndrome (hEDS, known also by EDS type III or Ehlers–Danlos syndrome hypermobility type (EDS-HT)). 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.[17]

Ehlers–Danlos hypermobility type can have severe musculoskeletal effects, including:

• Jaw laxity that may make an individual's jaw open and close like a hinge, as well as open further than the average.
• Neck pain that can lead to chronic headaches and is usually associated with a crackling or grinding sensation (crepitus).
• The spine may end up in a "round back" or inversely may extend too much into hyperlordosis. Individuals may also experience scoliosis.
• Joints commonly associated with hypermobility (wrists, knees, ankles, elbows, shoulders) may be at more severe risk to dislocate or strain.

Beighton score criteria: one point for each elbow and knee that hyperextends by 10 degrees or more (4 points), one for each little finger that bends back by 90 degrees (2 points), one for each thumb which can be touched to the forearm (2 points), and one for touching the floor with the palms.[19]

As of July 2000, hypermobility was diagnosed using the Beighton criteria. In 2017, the criteria changed, but still involve the Beighton score.[20] 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:

• A Beighton score of 5/9 or more (either current or historic)
• Arthralgia for more than three months in four or more joints

• A Beighton score of 1, 2 or 3/9 (0, 1, 2 or 3 if aged 50+)
• Arthralgia (> 3 months) in one to three joints or back pain (> 3 months), spondylosis, spondylolysis/spondylolisthesis.
• Dislocation/subluxation in more than one joint, or in one joint on more than one occasion.
• Soft tissue rheumatism. > 3 lesions (e.g. epicondylitis, tenosynovitis, bursitis).
• Marfanoid habitus (tall, slim, span/height ratio >1.03, upper: lower segment ratio less than 0.89, arachnodactyly; positive Steinberg finger / Walker wrist signs).
• Abnormal skin: striae, hyperextensibility, thin skin, papyraceous scarring.

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 Beighton Criteria. The Beighton score is measured by adding 1 point for each of the following:

• Placing flat hands on the floor with straight legs
• Left knee bending backward
• Right knee bending backward
• Left elbow bending backward
• Right elbow bending backward
• Left thumb touching the forearm
• Right thumb touching the forearm
• Left little finger bending backward past 90 degrees
• Right little finger bending backward past 90 degrees

Beighton test in a person with a 9/9 score

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 kinetic chain 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 is not the primary treatment for hypermobility, but can be used as an adjunct treatment for related joint pain. Nonsteroidal anti-inflammatory drugs 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.

For some people with hypermobility, lifestyle changes decrease symptom severity. In general, activity that increases pain is to be avoided. For example:

• Typing can reduce pain from writing.
• Voice control software or a more ergonomic keyboard can reduce pain from typing.
• Bent knees or sitting can reduce pain from standing.
• Unwanted symptoms are frequently reduced by some forms of yoga and weightlifting.
• Use of low impact elliptical trainer machines can replace high-impact running.
• Pain-free swimming may require a kickboard or extra care to avoid hyperextending elbow and other joints.
• Weakened ligaments and muscles contribute to poor posture, which may contribute to other medical conditions.
• Isometric exercise avoids hyperextension and contributes to strength.

• Bracing can be helpful for temporarily protecting unstable joints.