Generalized Joint Hypermobility in Healthy Female Koreans: Prevalence and Age-Related Differences

OBJECTIVE: Objective To evaluate the prevalence of generalized joint hypermobility (GJH) in healthy female Koreans and to determine whether the degree of GJH differs between children and adults. METHODS: Two groups of females were enrolled, a group of girls from an elementary school (n=404) and women from a call center (n=266). GJH was diagnosed using the Beighton score, which is composed of an evaluation of bilateral knees, elbows, thumbs, and fifth fingers as well as thoracolumbar joint. The GJH and localized hypermobility of each joint was compared between the two groups, and the pattern of hypermobility according to age and dominant hand was investigated. RESULTS: Total prevalence of GJH was 50.0% (335/750), and it was more frequently observed in the group of girls (58.9%, 238/404) than women (36.5%, 97/266). The degree of GJH expressed in terms of Beighton score was inversely correlated with age (p<0.05). Significant differences in localized hypermobility of the thumb and fifth finger were found between the two groups and were postulated as the cause for the decline in GJH with age. The pattern of decreased mobility proportional to aging differed between the two joints. Decreased mobility occurred equally on both sides of the thumb but was biased toward the fifth finger of the dominant side (mostly the right). CONCLUSION: The female Koreans appeared to have a high prevalence of GJH. The incidence of GJH decreased as age increased as a result of decreased mobility of the fifth finger on the dominant side.