Superior gluteal artery

The superior gluteal artery is the largest branch of the posterior division of the internal iliac artery, responsible for supplying blood to the gluteal region, including the gluteal muscles and surrounding structures. It is the primary blood vessel supplying the upper part of the buttock area and is critical for nourishing the tissues involved in movement and stability of the hip.

Location

The superior gluteal artery is located in the pelvis and buttock region. It arises from the posterior division of the internal iliac artery and exits the pelvis through the greater sciatic foramen, passing above the piriformis muscle. Once it enters the gluteal region, the artery travels between the gluteus medius and gluteus minimus muscles, branching into a superficial and deep branch. The superficial branch supplies the gluteus maximus, while the deep branch supplies the gluteus medius, gluteus minimus, and tensor fasciae latae muscles.

Anatomy

The superior gluteal artery is the largest branch of the posterior division of the internal iliac artery. It is a major supplier of blood to the gluteal muscles and nearby structures in the pelvic and buttock region. Below is a detailed description of its anatomy, including its origin, course, branches, and relations to other anatomical structures.

Origin

The superior gluteal artery arises from the posterior division of the internal iliac artery, which is one of the major arteries supplying the pelvic organs and structures. It is the largest branch of the posterior division and is typically the first branch to emerge, along with the iliolumbar and lateral sacral arteries.

Course

After originating from the posterior division of the internal iliac artery, the superior gluteal artery follows a course that leads it through the pelvis and into the gluteal region:

• Pelvic Course: The artery travels posteriorly within the pelvis, running between the lumbosacral trunk (a nerve formed by the L4 and L5 spinal nerves) and the first sacral nerve (S1).
• Exit from the Pelvis: The superior gluteal artery exits the pelvic cavity through the greater sciatic foramen, a large opening in the posterior pelvis. It passes above the piriformis muscle, distinguishing it from the inferior gluteal artery, which passes below the piriformis. The superior gluteal artery is the only structure to pass above the piriformis in the greater sciatic foramen.
• Entry into the Gluteal Region: After exiting the pelvis, the artery enters the gluteal region where it divides into its terminal branches. It travels between the gluteus medius and gluteus minimus muscles as it progresses deeper into the gluteal area.

Branches

The superior gluteal artery gives rise to superficial and deep branches, each of which supplies specific muscles and tissues in the gluteal region:

Superficial Branch:

The superficial branch runs posteriorly and enters the gluteus maximus muscle, which it supplies along with the overlying skin. This branch plays a key role in nourishing the largest muscle of the buttock.

Deep Branch:

The deep branch follows a more anterior and lateral course between the gluteus medius and gluteus minimus muscles, which it supplies. The deep branch itself divides into two smaller branches:

• Upper (Superior) Branch: This branch travels laterally to supply the gluteus medius and contributes to the blood supply of the iliac crest.
• Lower (Inferior) Branch: The inferior division runs deeper to supply the gluteus minimus and the tensor fasciae latae muscle. It also anastomoses (forms connections) with the lateral circumflex femoral artery, which provides additional blood supply to the hip and upper thigh.

Relations to Other Structures

The superior gluteal artery is closely related to several important anatomical structures in both the pelvis and the gluteal region:

• Piriformis Muscle: As the superior gluteal artery exits the pelvis through the greater sciatic foramen, it passes superior to the piriformis muscle, which serves as an important anatomical landmark. The inferior gluteal artery, in contrast, passes below this muscle.
• Gluteus Muscles: The artery travels between the gluteus medius and gluteus minimus muscles, which it supplies. Its deep branches distribute blood to both muscles, and the superficial branch supplies the gluteus maximus.
• Sciatic Nerve: The superior gluteal artery is located above the sciatic nerve as it exits the pelvis. This proximity is important in surgical interventions in the gluteal region to avoid nerve injury.

Anastomoses

The superior gluteal artery forms anastomoses (connections) with other arteries in the pelvic and gluteal regions, ensuring a robust vascular supply to the hip and surrounding structures:

• Inferior Gluteal Artery: The superior gluteal artery anastomoses with the inferior gluteal artery, which passes below the piriformis muscle. This connection provides collateral blood flow to the gluteal muscles.
• Lateral Circumflex Femoral Artery: The deep branch of the superior gluteal artery forms an anastomosis with the lateral circumflex femoral artery, which supplies the upper thigh and hip joint. This connection ensures that the muscles of the hip and thigh receive adequate blood supply.
• Medial Circumflex Femoral Artery: The superior gluteal artery may also anastomose with the medial circumflex femoral artery, contributing to the vascular supply of the hip joint.

Variations

There may be some anatomical variations in the origin or branching of the superior gluteal artery:

• Variations in Origin: While the superior gluteal artery typically arises from the posterior division of the internal iliac artery, in some cases, it may originate from the common iliac artery or have a different course in the pelvis.
• Additional Branches: In rare cases, the superior gluteal artery may give rise to additional branches that supply nearby muscles or structures.

Function

The superior gluteal artery plays a critical role in supplying blood to the gluteal region, particularly the muscles and structures of the buttocks and hip. Its function is divided among various tissues and muscles, all contributing to the movement, stability, and vascular support of the pelvic and lower limb regions. Below is a detailed breakdown of its functions.

 Blood Supply to the Gluteus Maximus Muscle

One of the primary functions of the superior gluteal artery is to provide oxygenated blood to the gluteus maximus muscle, the largest muscle in the buttocks and one of the most powerful muscles in the body. The superficial branch of the superior gluteal artery enters the gluteus maximus, nourishing its fibers and contributing to its strength and endurance.

Gluteus Maximus Function: The gluteus maximus is essential for movements like hip extension, particularly when rising from a sitting position, climbing stairs, or running. The blood supply provided by the superior gluteal artery ensures that this muscle can maintain its powerful contractions during these activities.

Blood Supply to the Gluteus Medius and Gluteus Minimus Muscles

The superior gluteal artery is responsible for providing blood to the gluteus medius and gluteus minimus muscles, which are essential for stabilizing the hip and controlling leg movement. The deep branch of the superior gluteal artery passes between these two muscles, delivering the oxygen and nutrients needed for their proper function.

• Gluteus Medius Function: The gluteus medius is crucial for hip abduction (moving the leg away from the body’s midline) and stabilizing the pelvis during walking. The superior gluteal artery ensures that this muscle receives adequate blood to perform these functions efficiently.
• Gluteus Minimus Function: The gluteus minimus, the smallest of the three gluteal muscles, also assists in hip abduction and internal rotation of the thigh. It helps stabilize the pelvis during walking and other weight-bearing activities. The artery’s supply to this muscle is vital for maintaining balance and proper hip mechanics.

Blood Supply to the Tensor Fasciae Latae Muscle

The superior gluteal artery also supplies the tensor fasciae latae (TFL) muscle, which plays a role in stabilizing the hip and knee during walking and running. The inferior branch of the deep division of the artery delivers blood to this muscle.

Tensor Fasciae Latae Function: The TFL muscle assists in hip flexion, abduction, and medial rotation. It works in conjunction with the gluteal muscles to stabilize the leg during movement, particularly while walking or running. The blood supplied by the superior gluteal artery ensures the muscle can function optimally, especially during prolonged physical activity.

Vascular Supply to the Hip Joint and Pelvic Structures

The superior gluteal artery contributes to the blood supply of the hip joint and other nearby pelvic structures. Through its anastomoses with other arteries, such as the lateral circumflex femoral artery and the medial circumflex femoral artery, it provides collateral blood flow to the hip joint.

Hip Joint Support: The superior gluteal artery’s contributions to the hip joint’s blood supply are essential for maintaining joint health and mobility. By nourishing the cartilage, ligaments, and surrounding structures of the hip, the artery plays a role in preserving joint function, especially during weight-bearing activities like walking and running.

Contribution to the Gluteal Vascular Network

The superior gluteal artery forms part of a comprehensive vascular network in the gluteal region, ensuring that blood is consistently delivered to the muscles and tissues. It connects with other arteries, creating a robust system of blood flow that supports the pelvis, hip, and thigh regions.

• Anastomoses with Inferior Gluteal Artery: The superior gluteal artery anastomoses with the inferior gluteal artery, ensuring that the entire gluteal region receives blood from multiple sources. This redundancy is important in case one artery becomes compromised or blocked.
• Anastomoses with Circumflex Arteries: The deep branches of the superior gluteal artery form anastomoses with the lateral circumflex femoral artery and medial circumflex femoral artery, which supply the thigh and hip joint. These connections help maintain blood flow to the upper leg and hip, even under varying physiological conditions.

Support for Postural Stability and Movement

By supplying blood to the gluteus medius, gluteus minimus, and tensor fasciae latae muscles, the superior gluteal artery plays an indirect but crucial role in postural stability and movement control. These muscles are essential for keeping the pelvis level during walking, running, and standing, as well as for controlling leg movement.

• Pelvic Stabilization: The gluteus medius and minimus muscles, supplied by the superior gluteal artery, prevent the pelvis from tilting during walking, helping maintain balance. Without adequate blood supply, these muscles would fatigue, leading to instability and difficulty maintaining proper posture during movement.
• Hip and Thigh Movement: The muscles supported by the superior gluteal artery also assist in moving the hip and thigh, particularly in abduction and rotation, contributing to a wide range of lower limb movements.

Role in Recovery and Healing

The superior gluteal artery also plays a role in tissue repair and recovery following injury or surgery in the gluteal region. The muscles and structures it supplies require adequate blood flow to heal properly, whether after trauma or surgical intervention.

Healing after Injury: The superior gluteal artery ensures that the gluteal muscles, tendons, and fascia receive the oxygen and nutrients needed for recovery following injuries such as strains, tears, or surgeries in the hip or buttock region. This vascular support helps speed up recovery and promotes proper tissue regeneration.

Clinical Significance

The superior gluteal artery is clinically significant due to its role in supplying blood to the gluteal muscles, hip joint, and surrounding structures. Its course above the piriformis muscle and its close proximity to the sciatic nerve make it an important structure during surgeries, such as hip replacement, pelvic surgeries, or procedures involving the gluteal region. Injury to this artery during surgery can lead to excessive bleeding, gluteal ischemia, or damage to surrounding nerves.

In cases of pelvic fractures or trauma to the buttocks, the superior gluteal artery may be at risk for injury, leading to hemorrhage and potential complications such as hematoma formation. Its involvement in the vascular supply of the hip joint also makes it significant in conditions like avascular necrosis, where compromised blood flow can lead to the deterioration of the femoral head. Additionally, the artery may become involved in gluteal artery aneurysms or be a source of gluteal pain due to its proximity to nerves.