Linea Aspera

linea aspera femoris

The linea aspera is a prominent longitudinal rough ridge on the posterior surface of the femoral shaft running between its lateral and medial lips along most of the femoral shaft length. It provides attachment for multiple muscles: adductor longus, adductor brevis, adductor magnus, biceps femoris short head, vastus medialis, vastus lateralis, and the lateral and medial intermuscular septa. It marks the posterior centre of the femoral shaft.

Region: Thigh

Clinical Relevance

Clinical Notes

The linea aspera is the reference landmark in femoral shaft fracture classification and surgical approach. Intramedullary nail position relative to the linea aspera confirms correct rotational alignment of the nail before locking: the distal locking screws should align with the lateral cortex with the linea aspera posterior. In femoral plating, the linea aspera is the anatomical reference for plate positioning. Periosteal stripping from the linea aspera during plating compromises the nutrient artery territory.

Pathology

Common Injuries & Conditions

Linea Aspera as Rotational Alignment Reference in IMN

After intramedullary nailing of a femoral shaft fracture, rotational alignment is confirmed by ensuring the distal fragment's linea aspera is in the posterior midline position, corresponding to the anatomical posterior position before fracture; asymmetry compared to the contralateral limb on fluoroscopy indicates malrotation requiring correction before locking.