Biometry of the femoral groove in foetuses. Anthropological and clinical interest

Seance of wednesday 22 march 2006 (ORTHOPEDIE)

Abstract

The femoral groove in humans, the only exclusively biped primate,is asymmetrical, with a lateral margin that is more elevated than themedial one. This asymmetrical patellar groove is a specificity of themodern human being. This feature might be caused by bipedalism.Nevertheless, a great anatomic variability in the shape of the femoralgroove has been described. Our aim was to achieve a biometryof the femoral groove in foetuses and to compare our results withthose published in adults by Wanner (1977) [27]. To date, this is thefirst biometry of the trochlear groove in foetuses. The analysis wasperformed in order to check the following hypothesis: the distal endof the bones is fixed in shape from the earliest foetal stage throughthe growth. Our results pointed out that a significant number offoetal specimens had an asymmetrical and deeply dug femoralgroove from the earliest foetal stage. This supports the hypothesisthat in the determination of the distal end shape of the femur, a partis played by genetic factors that have progressively appeared duringthe evolution. Thus, not only mechanical factors such as specificstress caused by bipedalism are responsible for the shape of thedistal femurs in adults. This work may serve as a base in order tobetter understand the femoral groove dysplasia that is in certaincases responsible for iterative patellar dislocations, and in which thetreatment remains controversial.