Joint hypermobility or double-jointedness is said to be present when a joint that can be stretched beyond what is called normal range is normal.
When generalized joint hypermobility is present with symptoms of muscle and joint pain, it is termed as Hypermobility syndrome.
It could be due to
- Malaligned joints
- Joint with the abnormal shape of articular surfaces
- Connective tissue disorder (such as Ehlers-Danlos syndrome, Marfan syndrome)
- Abnormal joint proprioception
Joint hypermobility can run in families suggesting a genetic basis too.
Most of the people with joint hypermobility do not have any problem but others especially those in sports may become prone to repeated joint injuries.
Beighton Score For Joint Hypermobility
The Beighton score is used for assessing the presence of joint hypermobility. However, it must be noted that the diagnosis of Hypermobility Syndrome or HMS should be made using the Brighton Criteria.
Beighton scoring is based on testing the simple movements.
Passive Dorsiflexion of Little Finger
In a normal individual, the little finger cannot be extended beyond 90 degrees, even passively. Score 0
If the passive extension [dorsiflexion] reveals this movement beyond 90 degrees – Score 1
Passive Dorsiflexion of Thumb
If thumb cannot be made to touch the flexor aspect of the forearm – Score 0
If thumb can be made to touch the flexor aspect of the forearm – Score 1
Hyperextension of left elbow
In most of the individuals, the range of movement of the elbow is 0-120 degrees. 0 signifies that arm can be made to straighten but a further movement is not possible. Any further extension movement of the elbow would result in arm bending backward.
Some normal individual may have a slight backward bending movement. To look for a hypermobile joint a cut off point of 10 degrees is kept.
If elbow cannot be bent backwards is less than 10 degrees [has less than 10 degrees of extension – Score 0
If elbow can be bent backwards more than 10 degrees [has more than 10 degrees of extension] – Score 1
Hyperextension of Knee
The concept of the elbow, when applied to the knee, would provide scores of the knee In a normal individual, the knee can not be straightened beyond 0 degrees. Further extension is known as hyperextension
Hyperextension of right knee beyond 10 degrees not present – Score 0
Hyperextension of right knee beyond 10 degrees present – Score 1
Individual is not able to rest the palms and hands on the floor with forward flexion [bending] of trunak with knees full extended – Score 0
Individual is able to rest the palms and hands on the floor with forward flexion [bending] of trunak with knees full extended – Score 1
Calculation of Score
The score is calculated by adding the scores of
- Both the thumbs
- Both the little fingers
- Both elbows
- Both knees
- One Trunk Movement
Maximum possible score thus becomes 9
4/9 score is considered significant.
Benign Joint Hypermobility Syndrome
Benign joint hypermobility syndrome, thought to be a connective tissue disorder, is the occurrence of pain in multiple joints in hypermobile individuals in the absence of systemic rheumatologic disease.
The entity is different from the disorders that cause local joint hypermobility and generalized joint laxity, such as Marfan syndrome and Ehlers–Danlos syndrome.
Hypermobility not associated with systemic disease occurs in 4% to 13% of the people.
Hypermobility may occur in several different connective tissue disorders including Marfan syndrome, EDS, and osteogenesis imperfecta, Down syndrome, homocystinuria and hyperlysinemia.
Benign joint hypermobility syndrome has a strong genetic component with an autosomal dominant pattern.
Pathophysiology of Benign Joint Hypermobility Syndrome
Why do some people have symptoms with hypermobile joints. Four factors have been suggested –
- Shape of the ends of the bones resulting in joint wear and tear
- Impaired proprioreception
- Fatigue of surrounding tissues
Pain in a hypermobile joint which may affect one or multiple joints is the most common symptom. This can occur at any age are often exacerbated by physical activity.
Though it may occur in any joint but knee and ankle are most commonly involved.
Other symptoms that may occur are are joint stiffness, myalgia, muscle cramps, and nonjoint limb pain.
There might be a history of double-jointedness or recurrent dislocations in the family.
Easy bruising, ligament or tendon rupture, congenital hip dysplasia, and temporomandibular joint dysfunction may be associated findings.
On physical examination, there might be a pain in joints on manipulation.
Other associated findings that might be present are [Suggesting some connective tissue disorder]
- Pes planus
- Genu valgum
- Marfanoid habitus
- Varicose veins
- Rectal or uterine prolapse
- Thin skin
People with hypermobility syndrome may develop other conditions caused by their unstable joints. These conditions include frequent sprains, tendinitis, or bursitis when doing activities that would not affect the normal individual.
Diagnosis of benign joint hypermobility syndrome is one of exclusion. Other causes like inflammatory, infectious, and autoimmune causes should be ruled out . Routine work up including a complete blood cell count, erythrocyte sedimentation rate, rheumatoid factor, antinuclear antibody test, serum complement levels, and serum immunoglobulin levels should be done.
By rule all of these are within normal limits in benign joint hypermobility syndrome. Aspiration of joint in cases who have joint effusion shows a noninflammatory pattern from meniscal and cartilage irritation.
Determining the Beighton score which is a measure of generalized joint laxity is essential for diagnosis making. A Beighton score of 4 or more points is considered indicative of generalized joint laxity. Brighton criteria which is based on Beighton score helps to establish diagnosis of benign joint hypermobility syndrome and also helps to distinguish it from other connective tissue disorders.
Brighton Criteria For Benign Joint Hypermobility Syndrome
- A Beighton score of 4/9 or greater (either currently or historically)
- Arthralgia for longer than 3 months in 4 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/wrist signs].
- Abnormal skin: striae, hyperextensibility, thin skin, papyraceous scarring.
- Eye signs: drooping eyelids or myopia or antimongoloid slant.
- Varicose veins or hernia or uterine/rectal prolapse.
The diagnois of benign joint hypermobility syndrome is made if
Two major criteria are present
There is one major and two minor criteria present
Four minor criteria are present
Treatment of Benign Joint Hypermobility Syndrome
Many individuals with joint hypermobility syndrome improve in adulthood. Treatments are individualized based on the manifestations.
The treatment of benign joint hypermobility syndrome consists of
- Lifestyle modification
- Change In Exercise Pattern
- Protection of jointsor
Nonsteroidal anti-inflammatory drugs are used for pain control. Restraining from aggravating activities can relieve the symptoms.
In long term, modification of activities that induce symptoms is part of the treatment. Vigorous and repetitive activities should be curtailed.
Patients need to be taught about the condition they have.. Overtraining, poor pacing, too maniy performances or athletic competitions, and focusing on joint flexibility rather than stability may all increase joint pain and the risk of injury.
They should be avoided. But it cannot be possible in all cases [for example athletes] and alternatives can be explored.
It is important that the individual with hypermobility remain extremely fit – even more so than the average individual – to prevent recurrent injuries. Regular exercise and physical therapy or hydrotherapy can reduce symptoms of hypermobility, because strong muscles help to stabilise joints.
Strengthening program to provide muscular stability and stabilization to the joint may be beneficial. Stretching techniques that are targeted to isolate tight muscles without stressing the surrounding joints may reduce symptoms.
Supportive splints along with appropriate footwear protect the joint, and supportive joint taping can improve joint proprioception.