Hello, and welcome back to muscle talk. Today we are going to be discussing the muscles that make up the glutes. The glutes are a set of three muscles that form the buttocks area. These muscles perform various functions synergistically, which we will discuss further. Now that we have an idea of what our topic is, let’s get started.
The glutes consist of the gluteus maximus, gluteus medius, and the gluteus minimus. The gluteus maxmimus is the largest, and most superficial of the gluteal muscles. It forms the bulk of the buttocks. The fascicles are thick and course, and as such it is a great site for intramuscular injection. It overlies the large sciatic nerve and covers the ischial tuberosity when standing. When we sit it moves superiorly leaving the ischial tuberosity exposed. It originates at the dorsal ilium, sacrum, and coccyx. It inserts at the gluteal tuberosity of femur. Its the major extensor of the thigh, and is most effective when the thigh is flexed and force is necessary, as in rising from a forward flexed position, or thrusting the thigh posteriorly in climbing stairs and running. It is generally inactive while standing and walking, and it laterally rotates and abducts the thigh.
The gluteus medius is a thick muscle largely covered by gluteus maximus . It originates between the anterior, and the posterior gluteal lines on the lateral surface of ilium. Insertion is by the short tendon into the lateral aspect of greater trochanter of femur. The medius abducts, and medially rotates the thigh as well as steadies the pelvis. Its action is extremely important in walking. The muscle of the limb planted on the ground tilts, or holds the pelvis in abduction so that pelvis on the side of the swinging limb does not sag. This way the foot of swinging limb can clear the ground.
The gluteus minimus is the smallest, and deepest of the three. It originates between the anterior and the inferior gluteal lines on the external surface of ilium. Insertion is at the anterior border of greater trochanter of femur. The gluteus minimus works synergistically with the gluteus medius.