Factors associated with joint mobility in an adolescent population.

Abstract

SUMMARY Fixed torque devices were used to measure joint mobility at three sites in 364 adolescents including 39 families with at least two siblings. Increasing age and being male were associated with reduced laxity, and a strong effect of family was observed in the 39 sibling sets studied. The population included 47 Asians whose mobility was similar to that of the non-Asians, though the female/male difference was apparently greater in the former group. None of the above conclusions apply to index finger hyperextension, and it is apparent that genetic and constitutional factors only affect mobility at some sites. Such observations could lead to a review of current scoring systems for clinical hypermobility. classes at a local school and two polytechnics. The polytechnic classes were added to extend the age range of the sample. The school had recently become coeducational and this combined with the differential self selection of individuals to study biology resulted in there being only 97 (26-6%) female compared with 263 (72-3%) male students (in four cases the sex was not recorded). Ninety five per cent of all subjects were aged between 11 and 20, though three were above 25 years. There were 47 children whose parents were either of Indian or Pakistani origin in the population studied; the remainder (excluding one with no record of ethnic origin) were European. In 39 instances there was more than one individual from the same family-37 sibling pairs and two trios.Joint mobility was measured for the following movements: index finger hyperextension, forearm rotation, and lower limb rotation. The last two represent composite movements and thus reflect mobility at more than one joint. Measurements were undertaken using fixed torque measuring devices first described by Jobbins et al.9 The particular devices used in this study have low levels of both within and between observer variability as previously described,10 making them appropriate for use in epidemiological studies. The method of measurement in this population has beerr reported elsewhere.2 In each class three trained observers were used, one for each measurement. During the course of the study five' individual observers were used. The constraint of timetabling resulted in some individuals not being tested for all three movements. 209

Pediatric Generalized Joint Hypermobility With and Without Musculoskeletal Complaints: A Localized or Systemic Disorder?

“…All group differences were additionally adjusted for age, gender, body height, and weight, as these are determinants for blood pressure, joint mobility, skin extensibility, and quantitative ultrasound measurements. 23,24,28,29 As shown in the fourth column of Table 2, this adjustment had only a marginal influence on the results. We further assessed whether findings concerning urinary excretion of collagen degradation products might explain group differences in other clinical characteristics.…”

Evaluation of general joint laxity, shoulder laxity and mobility in competitive swimmers during growth and in normal controls

“…Several studies have shown that hypermobility can either be inherited and/or acquired (Child, 1986;Klemp & Chalton, 1989). Gender, age, ethnic background and hormonal influences are factors suggested to have an impact on the degree of joint mobility (Beighton et al, 1973;Al-Rawi et al, 1985;Silman et al, 1987;Bulbena et al, 1992;Larsson et al, 1993). Carter and Wilkinson (1964) designed a score evaluating general joint laxity of five joints, and this was modified later in Beighton et al (1973).…”

General joint laxity in 1845 Swedish school children of different ages: age- and gender-specific distributions

“…Gender, age and ethnic background are the three of the most discussed factors that might have an impact on the degree of joint mobility. Hormonal factors have also been discussed, since earlier studies found that females tended to be more lax than males (5)(6)(7)(8)(9) and that the degree of laxity decreased with age (5,(8)(9)(10)(11)(12).…”