شيوع و اشكال هايپرموبيليتي مفصلي در دانش آموزان تهراني

Prevalence and features ofjoint hypermobility among school children in Tehran

Introduction: Joint hypermobility (JHM) represents an increased range of movement in the joints of normal population in the absence of underlying connective tissue disorder. To determine the prevalence and features of JHM among school children in Thehran, we conducted a cross-sectional study between January 2002 and Februa 2003. Methods: Using a multi-stage random sampling, we screened 1005 school children (501 girls and 504boys) with the mean age of 12.39 ± 3.25 year (range 6-19) from 5 different educational area of Tehran for the presence of JHM by a 0 to 9 scoring method; Carter-Wilkinson& Beighton system. Results: Generalized JHM (defined as a score ? 5) was found in 23.9% of the children, 14.1% of boys and 33.7% of girls (p< 0.0005). The prevalence of JHM was significantly greater in lower age group (6-12 year olds) in comparison with higher age group (13-19 year olds); 27.2% and 20.5%, respectively (p=0.012). The most common hypermobile joint was the thumb (97.9%), followed by elbow(87.5%), knee(78.3%), hand fingers (60.4%), and ultimately, trunk(23.3%). With the exception of US/LS ratio, we didnʹt find any noticeable differences in body measures and proportions between hypermobile and non-hypermobile students. Conclusion: We showed that the JHM is a common trait among Tehrani school children. This finding notifies more clinical attention to JHM among rheumatologists, pediatrics, and other concerned physicians. We believe, this high prevalence of JHM and its features seen in this study, probably are specific for Iranian populations.