A 72-year-old woman sustains an intracapsular fracture of the femoral neck. Six months after fixation, radiographs show collapse and sclerosis of the femoral head. Disruption of which arterial source best explains this avascular necrosis?

• A Inferior gluteal artery
• B Artery of the ligamentum teres from the obturator artery
• C Retinacular branches of the medial circumflex femoral artery ✓
• D First perforating artery

Explanation

In adults the femoral head is supplied chiefly by retinacular (capsular) branches arising from the medial circumflex femoral artery, which ascend along the neck inside the capsule. An intracapsular fracture tears these vessels. The artery of the ligamentum teres from the obturator artery supplies only a small area near the fovea in adults and cannot sustain the whole head, so it is not the decisive supply.

Reference: Moore Clinically Oriented Anatomy, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.