The relationship of joint hypermobility, bone mineral density, and osteoarthritis in the general population: the Chingford Study.

OBJECTIVE

The prevalence of hypermobility and its consequence in an aging female population is unknown. Case studies of patients with the benign joint hypermobility syndrome suggest both a tendency toward osteopenia and an association with premature osteoarthritis (OA). We assessed hypermobility and its relationship to bone mineral density (BMD) and OA in a postmenopausal female community population.

METHODS

Joint hypermobility was assessed by the Beighton and the (more quantitative) Contompasis scores in 716 female subjects under followup in the Chingford Study (age range 53-72, mean 61 yrs, SD 5.8).

RESULTS

We found 79 of 716 subjects (11%) had a hypermobility score > 1/9 on the Beighton scale (spine in 75/79); 82/716 had a Contompasis score > 22 (normal < 18). Only one had a 4/9 Beighton score indicative of generalized joint hypermobility. Subjects with Contompasis > 22 were more physically active and less likely to smoke. They had a reduced risk of knee OA (joint space narrowing) (OR 0.48, 95% CI 0.27-0.83, after adjusting for age, height, weight, and activity), but no change in risk of OA in spine or hands. Hip BMD was increased by 3% in this more hypermobile subgroup (p < 0.05). A similar effect was seen for knee OA, but not BMD in those with a Beighton score > 1.

CONCLUSION

Our data suggest that in this postmenopausal population the tendency to joint hypermobility may be a marker for fitness, manifested by reduced knee OA and increased hip BMD. The incidence of generalized hypermobility (Beighton > 4/9) was very low (0.14%) compared with the localized form (seen in 11%) and other studies. Those with mild degrees of hypermobility showed no evidence of premature OA or reduced BMD, as reported in some of the rarer heritable disorders of connective tissue.