Adductor brevis

The adductor brevis is a small, triangular muscle located in the medial compartment of the thigh. It plays an important role in adducting the hip and stabilizing the pelvis during movement. Understanding its anatomy and function is essential for clinical assessment and surgical procedures.

Introduction

The adductor brevis muscle lies deep to the adductor longus and anterior to the adductor magnus. It is primarily responsible for adduction of the thigh, but also assists in flexion and medial rotation of the hip joint. Despite its relatively small size, it is clinically significant due to its close relationships with neurovascular structures in the medial thigh.

Injuries to the adductor brevis, though less common than adductor longus strains, can cause medial thigh pain and limit hip mobility. Knowledge of its anatomy is also important in surgeries involving the medial thigh or pelvis.

Anatomy

Origin and Insertion

The adductor brevis originates from the body and inferior ramus of the pubis. Its fibers insert onto the proximal part of the linea aspera of the femur. This positioning allows it to exert force across the hip joint effectively.

Structure and Morphology

• Small, triangular muscle located between the adductor longus and adductor magnus
• Fiber orientation allows for powerful adduction of the thigh
• Size and shape can vary among individuals, sometimes overlapping with adjacent muscles

Relations

• Superficial: covered by adductor longus and gracilis muscles
• Deep: lies anterior to adductor magnus and posterior to pectineus
• Neurovascular relations: closely associated with branches of the obturator nerve and femoral vessels
• Medial thigh compartment: contributes to the boundaries of the femoral triangle

Innervation and Blood Supply

Innervation

The adductor brevis is primarily innervated by the obturator nerve. The anterior and posterior branches of this nerve provide motor fibers to the muscle. Variations in innervation may occur, but the obturator nerve remains the main source in most individuals.

Blood Supply

The muscle receives its blood supply from branches of the obturator artery, with additional contributions from the medial circumflex femoral artery and branches of the deep femoral artery. This vascular network ensures adequate perfusion during activity and supports healing following injury.

Function

The adductor brevis plays a crucial role in lower limb movement and stability. Its primary actions and contributions include:

• Adduction of the thigh at the hip joint
• Assistance in flexion of the hip, particularly from an extended position
• Medial rotation of the thigh during certain movements
• Stabilization of the pelvis during walking, running, and other dynamic activities

By working in coordination with other adductor muscles, the adductor brevis helps maintain balance and proper alignment of the lower limb during locomotion and athletic activities.

Clinical Significance

Muscle Strain and Injury

The adductor brevis is susceptible to strain, particularly in athletes involved in activities requiring rapid lateral movements or forceful adduction, such as soccer, hockey, and football.

• Mechanism of injury: sudden contraction or overstretching during sport
• Symptoms: medial thigh pain, tenderness, swelling, and limited hip movement
• Physical examination: pain on resisted adduction and palpation of the proximal medial thigh

Implications in Surgery

Knowledge of the adductor brevis anatomy is important in surgical procedures of the medial thigh and pelvis.

• Consideration during hernia repairs, femoral or obturator nerve surgeries
• Preservation during tendon harvest for reconstructive procedures
• Awareness of neurovascular structures to prevent inadvertent injury

Rehabilitation and Physical Therapy

Recovery from adductor brevis injuries involves a structured rehabilitation program.

• Stretching exercises to restore flexibility
• Strengthening exercises targeting adductor muscles
• Gradual return to sport-specific activities
• Prevention strategies including warm-up, conditioning, and technique training

Imaging and Diagnostic Evaluation

Imaging is useful in confirming injuries or evaluating anatomical variations of the adductor brevis.

• Ultrasound: First-line modality for detecting muscle tears or strains.
• MRI: Provides detailed assessment of muscle, tendon, and surrounding soft tissue involvement.
• CT scan: Rarely used but can identify complex trauma or surgical planning considerations.

Variations and Anomalies

The adductor brevis may exhibit anatomical variations that have clinical and surgical relevance.

• Variations in origin: some fibers may arise from the inferior pubic ramus alone or in combination with the body of the pubis.
• Variations in insertion: fibers may attach to different levels of the linea aspera or occasionally merge with adductor longus or magnus tendons.
• Accessory slips or muscular anomalies: rare additional fibers can influence function or complicate surgical dissection.
• Implications: awareness of these variations is important for imaging interpretation, surgical planning, and avoiding iatrogenic injury.

References

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