GLUTEUS MAXIMUS MYOLOGY
OVERVIEW
The Gluteus Maximus is the largest muscle in the body. Located on the posterior aspect of the hip joint, the Gluteus Maximus is the most superficial muscle of all gluteal muscles. The Gluteus Maximus originates from several different sites including the posterolateral aspect of the sacrum and coccyx, the sacrotuberous ligament, gluteal surface of ilium (behind the posterior gluteal line), thoracolumbar fascia and gluteal aponeurosis. From these origination sites, the fibers then run inferolateral toward the femur. While the superior three-quarters of the Gluteus Maximus converge to contribute to the IT Band, the inferior fourth of the muscle inserts onto the gluteal tuberosity of the femur via a broad aponeurosis. Because of these attachment sites, direction of the fibers, and the joints involved, the Gluteus Maximus is responsible for hip extension, hip external rotation, and playing a contributing role in abduction.
LOCATION
Superficial, posterior aspect of the hip joint.
ORIGIN
Posterior gluteal line of the ilium and portion of the bone superior and posterior to it
Posterolateral surface of the sacrum and the coccyx
Aponeurosis of erector spinae
Sacrotuberous ligament
Gluteal aponeurosis
Thoracolumbar fascia and its associated raphe
INSERTION
Tubercle of the iliotibial tract on the tibia via the IT Band
Gluteal tuberosity of femur
FUNCTION
Hip Extension
Hip External Rotation
Iliac fibers assist in abduction
Coccygeal fibers assist in some adduction
SHORT AND LONG POSITION
Because of the broad structure, the short and long positions of Gluteus Maximus will vary depending on which fibers one is attempting to target. The short position of this muscle can be found when the Gluteus Maximus' insertion site is closest to one of its origination sites. When attempting to find the long position for each division, it is easier to think about the antagonist muscle's short position.
COCCYGEAL DIVISION
The short position of the Coccygeal Division of the Gluteus Maximus can be found when the hip is in extension and the femur is slightly adducted toward the tailbone. External rotation should natural occur in this position.
The long position of the Coccygeal Division of the Gluteus Maximus can be found when the hip is in a degree of flexion that aligns with the short position of Diaphragmatic Division of the Psoas. This position looks like the maximum level of hip flexion with a degree of external rotation at the hip.
SACRAL DIVISION
The short position of the Sacral Division of the Gluteus Maximus can be found when the hip is in extension and the femur is headed toward the Sacrum. Some external rotation will natural occur in this position.
The long position of the Coccygeal Division of the Gluteus Maximus can be found when the hip is in a degree of flexion that aligns with the short position of Thoracic Division of the Psoas. This position looks like a level of hip flexion with a degree of adduction and slight external rotation at the hip.
ILIAC DIVISION
The short position of the Iliac Division of the Gluteus Maximus can be found when the hip is in extension and the femur is headed toward the Ilium. A slight degree of abduction will occur in this position. A small degree of external rotation may occur in this position.
The long position of the Iliac Division of the Gluteus Maximus can be found when the hip is in a degree of flexion that aligns with the short position of Lumbar Division of the Psoas. This level of hip flexion with a degree of adduction that will cause the knee to travel toward the belly button.
ANTAGONIST
Psoas Major: The three divisions of the Psoas Major correspond antagonistically to the three divisions of the Gluteus Maximus.
Coccygeal Division = Diaphragmatic Division
Sacral Division = Thoracic Division
Iliac Division = Lumbar Division