Adductor Brevis

Introduction

Introduction to Adductor Brevis

The adductor brevis is a triangular muscle situated deep to the adductor longus and pectineus in the medial compartment of the thigh. It is a key adductor of the hip joint and plays a role in hip flexion and medial rotation. Its position behind the adductor longus makes it an important anatomical landmark: the profunda femoris artery and the obturator nerve's anterior division pass between the adductor longus and brevis. The muscle is frequently involved in groin strains, although it is less commonly injured in isolation than the adductor longus. Its innervation by the obturator nerve provides diagnostic value in localising obturator nerve lesions and lumbar radiculopathies (L2–L4).

Study

1. Origin and Insertion

The adductor brevis originates from the outer surface of the body and inferior ramus of the pubis, between the gracilis medially and the obturator externus laterally. It inserts by an aponeurosis onto the upper part of the pectineal line of the femur and the proximal portion of the linea aspera, behind the insertion of the pectineus and proximal to the insertion of the adductor longus.

2. Relations

Anteriorly, the adductor brevis is covered by the adductor longus and the pectineus. The profunda femoris artery and vein lie directly anterior to the muscle, separating it from the adductor longus. The anterior division of the obturator nerve descends on its anterior surface. Posteriorly, the adductor brevis lies on the adductor magnus muscle, with the posterior division of the obturator nerve passing between them. Medially, it is related to the gracilis muscle. Laterally, it is in contact with the obturator externus muscle.

3. Nerve Supply

The adductor brevis is innervated by the anterior division of the obturator nerve (L2, L3, L4). The nerve enters the muscle on its anterior surface. In about 20–30% of individuals, the adductor brevis also receives a branch from the posterior division of the obturator nerve.

4. Blood Supply

The muscle receives its blood supply primarily from the obturator artery and from perforating branches of the profunda femoris artery. The venous drainage mirrors the arterial supply, emptying into the profunda femoris vein and the obturator vein.

5. Actions

The adductor brevis adducts the hip joint. It also assists in hip flexion and medial rotation. When the lower limb is fixed, it stabilises the pelvis in the coronal plane.

6. Clinical Relevance

Adductor brevis strains are less common than adductor longus injuries but occur in the same athletic contexts (rapid changes of direction, kicking). The muscle is a key surgical landmark: the plane between the adductor longus and brevis is a standard surgical approach to the proximal femoral shaft and the profunda femoris vessels. The obturator nerve's anterior division, which supplies the muscle, can be injured during pelvic surgery, lymph node dissection, or pelvic fractures, leading to weakness of hip adduction. Heterotopic ossification can develop within the adductor brevis after trauma.

Summary

Summary of Adductor Brevis

The adductor brevis is a deep medial thigh muscle that originates from the pubis and inserts on the pectineal line and upper linea aspera. It is innervated by the anterior division of the obturator nerve (L2–L4) and supplied by the obturator and profunda femoris arteries. It adducts, flexes, and medially rotates the hip. It serves as a landmark for the profunda femoris artery and obturator nerve and is clinically relevant in groin strains and medial thigh surgical approaches.