Morphometric study of acetabular depth and coverage and their clinical importance

Objectives: To measure acetabular parameters and to compare parameters of acetabulum between men and women, and right and left sides.

Methods: The study was conducted in PNS Shifa Hospital, Karachi from January to June 2021. Anteroposterior radiographs of both hips of 70 adults aged 20-70 years were included. The study consisted of 35 men and an equal number of women. We measured acetabular depth, femoral head coverage, acetabular inclination and acetabular depth and width. The acetabular depth was measured using Wiberg’s central edge (CE) angle and Sharp angle techniques. Femoral head coverage was determined using measurements between medial edge of hip joint space, lateral edge of acetabulum and femoral head. To determine acetabular inclination, Tönnis angle was measured. Acetabular depth & width ratio (ADR) was evaluated by dividing acetabular width by depth, and multiplying by 100.

Results: There was significant increase in Sharp angle and Tonnis angle in females on the left side as compared to males. Wiberg’s central edge angle and acetabular width to depth ratio showed insignificant increase in males as compared to females, whereas values of femoral head coverage were insignificantly more in women.

Conclusion: The acetabular parameters were insignificantly different in gender and between right and left sides, although mean values were within normal range. The larger ADR ratio in men was most likely due to increased body weight in them as compared to women.