THE STRAIGHT-LINE GRAPH IN LIMB LENGTH INEQUALITY - A NEW DESIGN BASED ON 182 DUTCH CHILDREN

Moseley's Straight Line Graph (M-SLG), which is based on growth data o btained in the 1940s and 1950s, is helpful for the timing of physiodes is. We investigated whether current growth data could improve this gra ph. We estimated growth curves based on recent data on 182 Dutch child ren, collected between 1979 and 1994, using repeated measure analysis of variance. In both boys and girls, the mean femur and tibia length h ad increased, when compared to the data collected by Anderson et al.(1 964). Based on our growth data, a new straight line graph (Rotterdam S traight Line Graph; R-SLG) was created. Its value was assessed by comp aring the difference between the predicted length of the short (i.e., not operated) limb at maturity with the final limb length. In a group of 34 children who underwent physiodesis up to 10 years ago, the R-SLG gave better prediction of limb length at maturity than the M-SLG did in 22 of 34 cases and equal results were obtained in 5 cases. We concl ude that our updated SLG can improve the prediction of final limb leng th and thus also the timing of physiodesis.