Joint laxity in idiopathic adolescent scoliosis.

Joint laxity was quantified by measuring the distance from the thumb tip to the forearm during passive apposition in 500 normal Southern Chinese women. Joint laxity was found to have a normal distribution throughout the population and to decrease with age. When 109 Chinese girls with idiopathic adolescent scoliosis were similarly tested they were found to have significantly more laxity, suggesting that the two conditions are associated.