An elderly woman sustains an intracapsular fracture of the femoral neck. On imaging six weeks later the femoral head shows features of avascular necrosis. Which artery, torn at the time of fracture, was the main source of blood to the head in her age group?

• A Artery of ligamentum teres from the acetabular branch
• B Retinacular branches of the medial circumflex femoral artery ✓
• C Descending branch of the lateral circumflex femoral artery
• D First perforating branch of the profunda femoris

Explanation

In adults the femoral head is supplied chiefly by retinacular (capsular) branches arising mainly from the medial circumflex femoral artery, which run along the neck beneath the synovial reflection. An intracapsular fracture tears these vessels, causing avascular necrosis. The artery of the ligamentum teres contributes little after childhood, which is why option A is tempting but wrong in an elderly patient.

Reference: Snell's Clinical Anatomy by Regions, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.