Study of human fetal tali calcaneal articular facets

Talus is the important tarsal bone which participates in the formation of talocrural, subtarsal and talocalcaneonavicular joints. In the subtalar region, anatomical variation is particularly present on the talus as well as on the calcaneus. The prior knowledge of anatomical setup of talus and its various articulations are significant in diagnosis of underlying pathology of the foot like Congenital telipes equinovarus, Pes planus, high arched foot etc. as a result there are changes in its morphology and also help in its treatment. Therefore, aims of the study are 1) to observe anatomical variations in human fetal tali by considering the presence and percentage of various patterns of calcaneal articular facets of tali, 2) To know whether the variation in patterns of calcaneal articular facets of tali, were predetermined or results due to walking habits, physique of a person and duration of weight bearing etc. in post natal life. This study was done in department of Anatomy, J. N. medical college, Aligarh (UP) India. Tali for this study were obtained from thirty human fetuses of late 2nd trimester and 3rd trimester without any apparent anomalies (Still birth or from infants who had died very soon after birth). Each fetal talus was carefully examined for the pattern of calcaneal articulating facets. The number of tali with a particular type of facets was noted and then they were classified into four groups. Type 1: Single facets were present in 46% of fetal tali. Type 2: Single articular facet, but divided into two parts by a prominent ridge in 27% of fetal tali. Type 3: Facet, partially divided by a non articulating groove and partly by a ridge in to two parts in 10% of fetal tali. Type 4: Continuity of the facet on the plantar aspect of head with the facet on the plantar surface of the body of talus was present in 17% of fetal tali. There is no literature available related to calcaneal articular facet in fetal tali for comparison of our results. Our study concludes that the presence of calcaneal articular facet in fetal tali probably are genetically determined which can be validated by imaging technique (MRI) in fetal life, being familiar with, may help in treating joint instability and correction of various foot deformity.