Modifications on dorsum of neck of talus (Squatting Facets and Trochlear Extensions) in Indians

Abstract

Objective: Habitual squatting in humans is associated with modifications of ankle especially the neck of the talus (squatting facets) and its trochlear surface (trochlear extensions) that characterize the strong pressure and traction forces on ankle joints in state of hyperdorsiflexion. Present study was done to find out variations and incidences of various types of modifications of neck of talus thoroughly and to determine regional peculiarities of these modifications in Indians. Material and Methods: 300 dry (150 right and 150 left) adult tali were taken for present study. Each talus was examined for the presence of various patterns of articular facets on neck of talus and extensions of its trochlear surface. Statistical analysis of data was performed by using Fisher exact test with 95% confidence limits. Results: Lateral squatting facet was found in 136 tali (45.3%). Incidences of medial, combined & continuous gutter like squatting facets were 7.7%, 3.3% & 4.3% respectively. Lateral and medial extensions of trochlear surface were found in 22.3% and 23.7% respectively. Conclusions: Modifications of the neck of talus (squatting facets and trochlear extensions) are result of prolonged squatting positions which is common habit of Indian population and incidences of these variations can be used as an anthropological marker for racial and regional diff erentiation of unidentified bones.