Hypermobility syndrome, also referred to as benign joint hypermobility syndrome is a rare hereditary connective tissue disorder seen in the pediatric age group. Its clinical manifestations are highly variable but the most common features are a chronic pain with hypermobile (hyperlaxity of) joints, hyperextensible skin, fragile tissues which bleed easily, and other extra-musculoskeletal signs.
Hypermobility syndrome (HM) or benign joint hypermobility syndrome (BJHS) is a hereditary connective tissue disorder seen in the pediatric age group. Some authors have defined joint hypermobility syndrome (JHS) as a condition which includes individuals with hypermobile joints accompanied by symptoms of unknown etiology   . Other authors state that hereditary connective tissue disorders may be associated with JHS and "benign JHS" are used to differentiate it from other more life-threatening connective tissue disorders like Ehlers Danlos syndrome (EDS), Marfan syndrome, and Loeys Dietz syndrome . According to Simpson , JHS is currently considered an inherited connective tissue disorder with features similar to those of Marfan syndrome and Ehlers Danlos syndrome type 3, hypermobility type.
Hypermobility syndrome is transmitted in an autosomal pattern. The penetrance is variable  with a majority of the patients having no identifiable collagen protein abnormalities although a few may have a deficiency of tenascin-X . There is often a family history of the syndrome.
Although symptoms can start at any age, they are typically noticed in childhood and adolescence. Females are affected more than males. The presenting complaint is usually severe, debilitating pain, which is aggravated by activity e.g pain in the lower limbs while walking or difficulty writing in school. Children report "cracking" joints, swelling in the joints (especially knees and ankles) lasting for several days, recurrent joint subluxations or dislocations which reduce spontaneously. Exercise, excessive movement and joint stress are believed to cause the chronic joint pain. A backache is another common symptom, especially in the lumbar region as it is the most mobile part of the vertebral column. Other common symptoms include myalgia, cramps, and stiffness of the joints . Affected patients claim to be double jointed and can voluntarily subluxate.
Entire Body System
- Military Personnel
Eleven patients including nine military personnel had evidence of soft tissue rheumatism with associated fibromyalgia in four and anxiety disorder in one. [ncbi.nlm.nih.gov]
- Coarctation of the Aorta
In the patient described here, the Marfanoid hypermobility syndrome was associated with coarctation of the aorta which was corrected surgically. [ncbi.nlm.nih.gov]
We report two cases of siblings presenting coexisting non-radiographic axial spondyloartrhritis and joint hypermobility syndrome, complaining of back pain with morning stiffness, enthesitis, peripheral arthralgia, high erythrocyte sedimentation rate and [ncbi.nlm.nih.gov]
Its major criteria are a Beighton score of 4/9 or greater and arthralgia, but the diagnosis can also be based on the presence of minor criteria, including abnormal skin and joint (sub)luxations. [ard.bmj.com]
People with HS can suffer from subluxations and dislocations.  Diagnostic Procedures Brighton criteria Major Criteria: Beighton Score of 4/9 Arthralgia for 3 months in 4 joints Minor Criteria: Beighton score of 1–3 Arthralgia in 1–3 joints History [physio-pedia.com]
- Joint Swelling
While some children may have no symptoms, others may have joint and muscle pains or mild joint swelling in the late afternoon or evening or after exercise. These aches and pains are more common in the knees, elbows, and calf and thigh muscles. [rheumatology.org]
Children report "cracking" joints, swelling in the joints (especially knees and ankles) lasting for several days, recurrent joint subluxations or dislocations which reduce spontaneously. [symptoma.com]
Although brief episodes of joint swelling can occur in hypermobility syndrome, the presence of acute symmetrically tender joints should prompt reconsideration of the diagnosis.  The term "double jointed" is often used as a synonym for hypermobility [jmgims.co.in]
swelling  Clumsiness  Enhanced flexibility  Chronic pain  Little changes of the skin ,  Greater risk in failures in tendon, ligament, bone, skin and cartilage  Functional gastro-intestinal disorders  Chronic headache ,  [physio-pedia.com]
Occasionally episodes of joint swelling lasting hours to days, joint dislocations, or more commonly subluxations with spontaneous reduction are reported. [ped-rheum.biomedcentral.com]
- Leg Pain
Symptoms are usually bilateral, in the low back, buttocks, or thighs, although some individuals may experience only leg pain and, in a few cases, the leg pain may be unilateral. [ssa.gov]
[…] effusion of affected joint(s)- (foot, ankle, knee, hip, back, neck, shoulder, elbow, wrist, finger)  Back pain ,  Osteoarthritis Delayed motor development Congenital hip dislocation Exercise-related/post-exercise-related pains  Nocturnal leg [physio-pedia.com]
More about leg pain Children with joint hypermobility may also experience back pain due to poor posture and muscle weakness. [skillsforaction.com]
Imaging: Patients with benign joint hypermobility syndrome have a tendency for osteopenia and premature OA. Diagnostic Criteria: Brighton criteria have long been used. Recent Brighton criteria expand the ability to make this diagnosis. [rheumaknowledgy.com]
Presence of excessive hypermobility; Concern over a rare form of bone disorder associated with collagen deficiency e.g. osteogenesis imperfecta; Nerve root or cord compression consequent on hypermobility or nerve tethering (e.g. cauda equina syndrome); Osteopenia [web.archive.org]
[…] generalized joint hypermobility with recurrent subluxations Skin hyperextensibility AD Type I procollagen COL1A1 Congenital bilateral hip dislocation Tissue fragility, including atrophic scars COL1A2 Easy bruising Muscular hypotonia Kyphoscoliois Mild osteopenia [ped-rheum.biomedcentral.com]
[…] hypermobility type. ( 28180909 ) Baeza-Velasco C....Hamonet C. 2017 24 Multiple fractures in infants who have Ehlers-Danlos/hypermobility syndrome and or vitamin D deficiency: A case series of 72 infants whose parents were accused of child abuse and neglect [malacards.org]
Hypermobility: an important but often neglected area within rheumatology. Nat Clin Pract Rheumatol. Oct;4(10):522-4. Grahame R, Bird H, Child C. 2000. [web.archive.org]
- Urinary Incontinence
The aim of our study was to determine whether lower urinary tract symptoms (LUTS), including urinary incontinence (UI) and anterior compartment prolapse, are more common in women with BJHS than in the normal population. [ncbi.nlm.nih.gov]
incontinence that occurs because the pelvic floor muscles are too weak to prevent urination low blood pressure (hypotension), which may lead to fainting hernias - an internal part of the body, such as an organ, pushes through a weakness in the muscle [hse.ie]
incontinence that occurs because the pelvic floor muscles are too weak to prevent accidental urination hernias – an internal part of the body, such as an organ, pushes through a weakness in the muscle or surrounding tissue wall varicose veins – swollen [your.md]
- Sexual Dysfunction
OBJECTIVE: To determine whether pelvic organ prolapse (POP) and sexual dysfunction are more severe in women with benign joint hypermobility syndrome (BJHS) than in the normal population. DESIGN: Case-control study. [ncbi.nlm.nih.gov]
Common gynecologic findings were dysmenorrhea (82.9%), meno/metrorrhagias (53.7%), irregular menses (46.3%), and dispareunia/vulvodinia (31.7%). Forty women were nulliparous and 42 had one or more pregnancy for a total of 93 diagnosed conceptions. [ncbi.nlm.nih.gov]
The condition is often misdiagnosed as young children normally have an extensive range of motion at all their joints. The "Beighton score" has been used to diagnose hypermobility but the scores are variable depending on investigators. So currently the Villefranche classification  which includes clinical signs, family history, major and minor criteria is used for diagnosis. The major criteria are joint hyperlaxity, skin hyperextensibility, and no evidence of skin or soft tissue fragility. The minor criteria are a family history of the syndrome, recurrent joint instability, and the ability to bruise easily. Limitation of the Villefranche classification is that it does not account for extra-musculoskeletal manifestations.
The workup depends upon a detailed patient history, family history of joint hypermobility syndrome and thorough physical examination to look for hypermobile joints and signs of tissue fragility. Genetic testing may be useful in the diagnosis of the syndrome. Radiograph findings include small calcifications in the subcutaneous tissues. Magnetic resonance imaging can help to detect white matter lesions .
As gene mutations have not been identified as yet, prenatal testing cannot be recommended. However genetic counseling should be considered if there is a family history.
[…] coexisting non-radiographic axial spondyloartrhritis and joint hypermobility syndrome, complaining of back pain with morning stiffness, enthesitis, peripheral arthralgia, high erythrocyte sedimentation rate and C-reactive protein level and positive HLA-B27 [ncbi.nlm.nih.gov]
Chlamydia trachomatis); more common in human leukocyte antigen (HLA) B27 tissue-type males; see keratoderma blenorrhagicum restless-leg syndrome overwhelming need to move the lower limbs constantly; characteristic of chronic renal failure; thought to [medical-dictionary.thefreedictionary.com]
Hemochromatosis is a genetic disease related to human leukocyte antigen (HLA) A3, B7, and B14 histocompatability antigens resulting in increased iron absorption from the gastrointestinal tract and deposition of iron in tissues. [ncbi.nlm.nih.gov]
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