What is the anatomy and function of the gluteus medius muscle?

From the Guidelines

The gluteus medius is a fan-shaped muscle located on the lateral surface of the pelvis, beneath the gluteus maximus, playing a crucial role in hip abduction and stabilization during walking and standing. The muscle originates from the outer surface of the ilium between the anterior and posterior gluteal lines and inserts on the greater trochanter of the femur. Its primary function is to abduct the hip, moving the thigh away from the midline of the body, and it also assists in hip internal and external rotation through its anterior and posterior fibers, respectively. During activities such as walking and standing, the gluteus medius serves a vital stabilizing function by preventing the pelvis from dropping on the opposite side when weight is shifted to one leg, a mechanism known as the Trendelenburg gait. This muscle is innervated by the superior gluteal nerve (L4-S1) and receives its blood supply from the superior gluteal artery.

Key Functions and Clinical Importance

• Hip abduction: The primary role of the gluteus medius is to abduct the hip, which is essential for maintaining balance and preventing falls.
• Stabilization: It plays a crucial role in stabilizing the pelvis during single-leg activities, such as walking or standing on one leg.
• Rotation: The muscle assists in both internal and external rotation of the hip through its different fiber portions.
• Prevention of gait abnormalities: Weakness in the gluteus medius can lead to a Trendelenburg gait, characterized by the pelvis dropping toward the unsupported side during the swing phase of walking.

Diagnostic Imaging

Imaging modalities such as MRI and ultrasound (US) can be used to assess the gluteus medius muscle and its tendon for abnormalities, including tendinopathy, partial tears, and complete tears or avulsions 1. MRI is particularly useful for evaluating peritrochanteric structures, including the gluteus medius and minimus muscles, abductor tendons, and the trochanteric bursa 1. US can identify continuity of the reattached tendon after surgical repair and demonstrate tears or avulsions in both nonsurgical and postsurgical patients 1.

Clinical Implications

Strengthening the gluteus medius muscle is important for maintaining proper hip mechanics, preventing lower extremity injuries, and ensuring stability during single-leg activities. Weakness or injury to this muscle can lead to significant morbidity, affecting an individual's quality of life and increasing the risk of falls and other injuries. Therefore, strengthening exercises targeting the gluteus medius should be considered an essential component of rehabilitation programs for patients with hip or lower extremity injuries, or those at risk of falls.

From the Research

Gluteus Medius Anatomy and Function

The gluteus medius muscle is a key component of the hip anatomy, playing a crucial role in movement and stability. Some of the key points about its anatomy and function include:

• The gluteus medius muscle is located on the outer aspect of the hip and is one of the three gluteal muscles, along with the gluteus maximus and gluteus minimus 2.
• It originates from the outer surface of the ilium and inserts into the greater trochanter of the femur 3.
• The primary function of the gluteus medius muscle is to abduct the hip, or move the leg away from the midline of the body 3.
• It also plays a role in hip rotation and stabilization, helping to maintain proper alignment and movement of the hip joint 2.

Clinical Relevance

The gluteus medius muscle is often implicated in various hip and lower extremity conditions, including:

• Greater trochanteric pain syndrome, which is characterized by pain and inflammation in the area around the greater trochanter 4, 5.
• Gluteus medius tendinopathy, which is a condition characterized by degeneration and inflammation of the gluteus medius tendon 2, 6.
• Treatment options for these conditions may include corticosteroid injections, platelet-rich plasma injections, physical therapy, and exercise programs aimed at strengthening the gluteus medius muscle and improving hip function 4, 2, 5, 3, 6.

Exercise and Rehabilitation

Exercise and rehabilitation programs for the gluteus medius muscle often focus on strengthening and stabilizing the hip joint, and may include:

• Side-lying clamshell exercises, which target the gluteus medius muscle and help to improve hip abduction and rotation 3.
• Hip abduction exercises, which can help to strengthen the gluteus medius muscle and improve hip function 3.
• Altering hip orientation during exercise, such as varying hip flexion angle or rotation, can affect the activation of the gluteus medius muscle and other surrounding muscles 3.