Objectives. Children with generalized hypermobility of the joints and musculoskeletal complaints frequently visit pediatric clinics, but many show no currently known collagen or other possibly related diseases. Whether the symptoms are confined to the musculoskeletal system is unknown. We assessed whether such children have detectable differences in laxity of connective tissue present in organ systems other than joints. We also assessed whether children with generalized joint hypermobility and musculoskeletal complaints have more profound systemic changes in connective tissue of various organ systems as compared with children with generalized joint hypermobility without musculoskeletal complaints.
Methods. Anthropometrics, range of joint motion, muscle strength, skin extensibility, blood pressure, quantitative ultrasound measurements of bone, and degradation products of collagen were studied in 15 prepubertal children with generalized joint hypermobility and musculoskeletal complaints and compared with a population-based reference group of 95 nonsymptomatic prepubertal children. Symptomatic hypermobile children were also compared with children of the population-based reference group who had asymptomatic hypermobility of the joints (n = 16).
Results. Children with symptomatic generalized joint hypermobility had significantly higher skin extensibility (5.6 mm/15 kPa, 95% confidence interval [CI]: 4.0–7.1), lower quantitative ultrasound measurements (speed of sound: −26.8 m/s; 95% CI: −41.1 to −12.6) in bone, and lower systolic and diastolic blood pressure (−8.0 mmHg, 95% CI: −13.3 to −2.8; and −6.0 mmHg, 95% CI: −10.0 to −2.2, respectively) as compared with the total reference group. Also, they had significantly lower excretion of urinary hydroxylysylpyridinoline cross-links (mean difference: −51.3 μmol/mmol; 95% CI: −92.2 to −10.4) as well as lysylpyridinoline cross-links (−18.7 μmol/mmol; 95% CI: −36.9 to −0.5). Age, gender, body weight, height, and particularly cross-links excretion did not explain group differences in clinical and bone characteristics. After adjustment for age, gender, body weight, and height, children with symptomatic generalized joint hypermobility (n = 15) had significantly higher total range of joint motion (117.8 degrees; 95% CI: 77.7–158.0), skin extensibility (3.5 mm/15 kPa; 95% CI: 1.6–5.3), lower quantitative ultrasound measurements in bone (speed of sound: −27.9 m/s; 95% CI: −48.4 to −7.5), borderline lower diastolic blood pressure (−4.9 mmHg; 95% CI: −10.7–0.9), and significantly higher degradation products in urine (hydroxyproline/creatinine: 21.2 μmol/mmol; 95% CI: 2.3–40.1) as compared with asymptomatic hypermobile children of the total reference group (n = 16). After adjustment for possible confounders, children with generalized joint hypermobility without musculoskeletal complaints had a significantly higher total range of joint motion and more profound skin extensibility, as compared with the reference group (n = 79).
Conclusions. Clinically manifested symptoms in otherwise healthy children with generalized joint hypermobility are accompanied by increases in the laxity of other body tissues. Thus, generalized joint hypermobility with musculoskeletal symptoms does not seem to be restricted to joint tissues. In symptomatic hypermobile children, a more systemic derangement was also present as compared with asymptomatic hypermobile children.
dear collegue, thank you for your question. We recently assessed motor development in 72 children with generalised joint hypermobility and concluded that a severe delay in motor development was found in 23 of 72 children with generalised joint hypermobility (32%). (submitted for publication). We often measure weakness of the proximal muscles of the hip-joint (isometric hand held myometry compared to reference values for children). We also found that when muscle strength is normal, after extensive exercise muscle strength decreases possibly due to a lack of coordination and muscle co contraction
I often see children with generalized joint hypermobility for developmental delay most often for gross motor skills though at times with fine motor skill difficulties. Many of these children have been seen by physical and occupational therapists whose evaluations are notable for weakness especially in the proximal muscles. I am appreciative of the information provided in this article and wonder if any of the children evaluated in this study with generalized joint hypermobility had developmental issues.
dear collegue, thank you for your interest in our article. We measured besides body height and weight also armspan and sitting height. Armspan divided through body height did not extend 1.07, as is a criteria for Marfan syndrome. I our population we do have children with Marfanoid habitus. Since no clear criteria regarding clinical assessment have been made to distinguish pathology from normality we do not know if these children have a mild form of Marfan syndrome or a variation of normality. This is also the case in Ehlers Danlos syndrome. The distinction between the benign hypermobility syndrome and Ehlers Danlos type III is made on discutable criteria, since no collagen defect can be found yet. Clinical assessment of hypermobility with the Beighton or Bulbena scores is also very discutable. Generalised joint hypermobilty with a hyperextensible skin is not always pathological. In order to find answers, we are developing a new clinical instrument and already gathered reference values of 500 children and young adults. We hope that based on simple but clear and reliable measurements of joint motion and skin eventually combined with collagen data will lead to an instrument by which we can distinct normality from pathology. I hope that i was able to answer all the questions, sincerely yours dr. raoul engelbert
I read with extreme interest your article and I am happy to see that you are describing exactly the same that we see in adults. My patients with Benign Joint Hypermobility Syndrome (BJHS) besides hypermobility of joints have Disautonomia (Hypotension, dizziness, fainting spells, cold intolerance, chronic fatigue), osteopenia/osteoporosis, abnormal skin, soft tissue rheumatism, eye signs (drooping eyelids or miopia), varicose veins or hernias or uterine/rectal prolapse. Besides this, many have Marfanoid habitus. I am interested to know if you see Marfanoid children with hypermobility, without having Marfan. In adults, this is very frequent in Chile and I think that this must be a genetic mutation related to an Hereditary Alteration of the Collagen Fibers. I do not know if asymptomatic hypermobile adults (10% of our population) do or do not have other organ involments. This would be interesting to find out. As you see in pediatrics, symptomatic joint hypermobile patients are very frequent in my private practice also, they constitute 34% of all my patients.