Gluteus maximus

Musculus gluteus maximus

A large, thick, quadrilateral muscle forming the prominence of the buttock. It originates from the posterior gluteal line of the ilium, sacrum, coccyx, and sacrotuberous ligament. It inserts on the iliotibial tract and gluteal tuberosity of the femur.

Type Muscle
Body System Muscular
Body Region Hip
Parent Structure gluteal muscle
Latin Name Musculus gluteus maximus
FMA ID 22314

Function

The largest and most powerful muscle in the body. Primary extensor and lateral rotator of the hip. Essential for standing from a seated position, climbing stairs, running, and maintaining upright posture.

Clinical Significance

Gluteus maximus weakness (Trendelenburg gait) results from inferior gluteal nerve injury. Gluteal muscle atrophy occurs with prolonged immobility. The muscle is used in myocutaneous flap surgery for pressure ulcer coverage.

Frequently Asked Questions

Why is the gluteus maximus considered the largest muscle in the body?
The gluteus maximus is the largest muscle by volume and mass in the human body, forming the bulk of the buttock. It originates from a broad area including the ilium, sacrum, and coccyx and inserts on the iliotibial band and the gluteal tuberosity of the femur. Its large cross-sectional area reflects its role in generating powerful hip extension forces needed for climbing, sprinting, and rising from seated positions.
What are the primary actions of the gluteus maximus?
The gluteus maximus is the primary extensor and lateral rotator of the hip joint. It is particularly important for powerful activities requiring hip extension against gravity, such as climbing stairs, rising from a seated position, running, and jumping. The upper fibers also contribute to hip abduction, while the lower fibers assist in adduction.
What is the Trendelenburg gait and how is it related to the gluteus maximus?
Trendelenburg gait is actually caused by gluteus medius weakness, not gluteus maximus weakness. Gluteus maximus weakness produces a 'gluteus maximus lurch'—a backward trunk lean over the affected hip during stance phase to keep the center of gravity over the weight-bearing limb. This compensates for the inability of the weakened gluteus maximus to extend the hip. Gluteus maximus weakness follows injury to the inferior gluteal nerve.
What is the inferior gluteal nerve and what happens when it is injured?
The inferior gluteal nerve (L5, S1, S2) is the sole motor nerve to the gluteus maximus. Injury to this nerve—from hip surgery, posterior hip dislocation, or pelvic tumors—causes gluteus maximus paralysis. Affected patients have difficulty climbing stairs, rising from a chair, and running, while walking on flat ground may be relatively preserved.
How is the gluteus maximus used in reconstructive surgery?
The gluteus maximus myocutaneous flap is a well-vascularized tissue flap used in reconstructive surgery to cover pressure ulcers over the sacrum and ischium, which are common in bedridden patients. The muscle's robust blood supply from the superior and inferior gluteal arteries makes it an excellent choice for covering large, deep wounds that require substantial tissue bulk.

Related Structures

anterior internodal tract anterior internodal fasciculus aponeurosis aponeuroses atrioventricular node A-V node Bachmann's bundle anterior interatrial band Biceps brachii Musculus biceps brachii bundle of His A-V bundle cardiac muscle tissue of myocardium cardiac Purkinje fiber cardiac Purkinje fiber

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Educational Disclaimer

This content is for educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare provider for medical decisions.

Data sources: Terminologia Anatomica, Foundational Model of Anatomy, Wikidata.