Hip Retinacular Fibres

fibrae retinaculares capsulae coxae

The retinacular fibres of the hip are reflections of the hip joint capsule onto the femoral neck, forming longitudinal bands (retinacula of Weitbrecht) that carry the retinacular blood vessels supplying the femoral head. They run along the anterosuperior, anteroinferior, and posterior femoral neck from the capsular insertion at the intertrochanteric line.

Region: Thigh

Biomechanics

Function & Actions

Carry the retinacular blood vessels (branches of the medial circumflex femoral artery) to the femoral head; provide minor secondary capsular stability.

Clinical Relevance

Clinical Notes

The hip retinacular fibres are the conduit for the critical blood supply to the femoral head. Intracapsular femoral neck fractures disrupt the retinacular vessels, causing avascular necrosis of the femoral head in up to 30% of displaced fractures. Posterior hip dislocation strips the posterior retinaculum. Hip arthroscopy capsular repair restores retinacular tension. The anterior retinaculum is the primary blood supply pathway and its preservation is critical in femoral neck fracture reduction.

Pathology

Common Injuries & Conditions

Retinacular Vessel Disruption

Tearing of the femoral neck retinacular fibres in displaced intracapsular hip fractures interrupting medial circumflex femoral artery supply to the femoral head, producing avascular necrosis in 15-30% of cases.