In which fracture pattern is the risk of avascular necrosis of the femoral head HIGHEST?

• A Basicervical femoral neck fracture
• B Intertrochanteric fracture (AO 31-A2)
• C Subtrochanteric fracture (Seinsheimer type II)
• D Subcapital femoral neck fracture (displaced — Garden III/IV) ✓

Explanation

The femoral head blood supply (predominantly from the medial femoral circumflex artery via retinacular vessels) is most vulnerable in displaced intracapsular (subcapital) femoral neck fractures. Garden Grade III/IV (displaced) fractures disrupt the retinacular vessels, leading to AVN in 15-30% of cases and non-union in 10-30%. The intracapsular location also means hematoma is contained under pressure, further compromising vascularity. Basicervical, intertrochanteric, and subtrochanteric fractures are extracapsular and have very low AVN risk as the blood supply is not compromised.

Reference: Maheshwari Essential Orthopaedics, 6th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.