Gluteus Muscle

What is Gluteus Muscle?

The gluteal muscle is the group of muscles that form the buttocks of a human body. The gluteal region anatomically is located posterior to the pelvic girdle at the proximal end of the femur. Muscle of the gluteal region can be broadly divided into two groups which include, “superficial abductors and extenders” and the second group is called “deep lateral rotators”. Both of these muscles work together to form. Both these groups of muscle are required for the movement of the lower limb attached from the hip joint. 

Superficial Abductors and Extenders- These are the class of muscle that constitute tensor fascia lata and, gluteal maximus, gluteus medius, and gluteus minimus. The primary role of these muscles is to perform the abduction and extension of the femur. 

Deep Lateral Rotators- These are the class of muscles involved in the lateral rotation of the femur. This class of muscle include gemellus superior, gemellus inferior, quadratus femoris, obturator internus and, piriformis. 


Gluteus

These are a family of the muscle that is more commonly known as buttock muscle. As the name suggests the gluteal region buttock muscles are the muscles that mainly form the buttocks of the human body. They originate from the ilium and sacrum and are attached to the proximal posterior end of the femur. They assist in the movement of the lower limb of the body.  Three types of individual muscle form the gluteal region, they are-

  1. Gluteus maximus

  2. Gluteus medius

  3. Gluteus minimus


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Gluteus Maximus 

It is the largest among all the gluteal muscles. It is the proximal-most muscle of the buttocks, it originates from the gluteal surface of the ilium and dorsal surface of the lower part of the sacrum. It has an attachment to the side of the coccyx. It slopes around the buttocks making a 45-degree angle.  It then enters into the iliotibial tract. It attaches to the femur by entering the gluteal tuberosity of the femur. The gluteal maximus is supplied with the inferior gluteal nerve. The gluteal maximus is supplied with inferior nerve artery and superior nerve artery. The insertion of the gluteus maximus has two main ends that are, the iliotibial tract and gluteal tuberosity of the femur. Superficial muscles that form the upper larger part of the buttocks collectively form a thick tendinous lamina that enters into the iliotibial tract. The deeper fibre of the lower portion is inserted into the gluteal tuberosity of the femur, the deep fibre is seen to be in association with three bursae.


Functions- 

There are the following main functions of the gluteus maximus.

  1. They are the main extensor of the thigh

  2. They are primarily involved in the lateral rotation of the thigh.

  3. It acts as a tensor for fascia lata.

  4. It helps in maintaining the posture by providing support to the pelvis, it is easily observable in an erect posture.

  5. The lower part of the muscle performs abduction for the limb, whereas the upper fibre of the gluteus muscle is involved in the abduction of the hip joint.


Gluteus Medius

The Gluteus medius is a shaped muscle that lies just below the gluteus maximus, it is located in between the gluteus maximus and gluteus minimus. It is dense thick and radiating in nature it is located at our surface of the pelvis where two-third of it is covered by the gluteal aponeurosis and the posterior third is covered by the gluteus maximus. It originated from the gluteal surface of the ilium between the anterior gluteal line and posterior gluteal line. All the fibres of the gluteus median converge to form a tendon. This tendon then inserts itself into the lateral surface of the greater trochanter of the femur. It has innervation of the superior gluteal nerve. A bursa act as a barrier between the tendon and the greater trochanter of the femur on which it sides.

Variation of the gluteus medius- There may be slight variation in gluteus medius in the population. Some of the tendons of the muscle are not very firmly attached to the piriformis, it is one of the six muscles that are involved in the lateral rotation of the gluteal region. Another variation is the length of the fibre some of the fibre end on the tendon, and do not contribute much to the formation of the strong tendon.

A disorder associated with gluteus medius- Trendelenburg' sign is a disorder of the nerve plexus of the superior gluteal nerve.


Functions- 

There are the following functions of the muscle.

  1. They act as a strong abductor of the thigh

  2. They are involved in the medial rotation of the lower limb

  3. The posterior fibre of the muscle is also involved in the lateral rotation of the limb.

  4. Both the anterior and posterior parts work together to stabilize the pelvic on a coronal plane. 


Gluteus Minimus

It is the smallest and deepest gluteal muscle. It is located just below the gluteus medius. It is similar in shape to the medius muscle, it also has a fan-shaped structure, these structures allow maximum strength and abduction to the muscle.it originates from the gluteal surface of the ilium between the anterior gluteal line and the inferior gluteal line. It then converges to form a tendon where it inserts into the anterior border of the greater trochanter of the femur. This insertion provides an expansion to the capsule of the hip joint. It is supplied with a superior gluteal nerve that commands the action of the gluteal region. A bursa is found in between the tendon and the greater trochanter.

A disorder associated with gluteus minimus- the lower limb can undergo complete paralysis in case of superior gluteal nerve palsy, which means damage in the nerve of the muscle. It can cause highly reduced abduction and extension property of the lower limb.


Functions- 

there are the following functions of the gluteus minimus in the body.

  1. They perform high abduction for the thigh

  2. The anterior fibres help in flexing the hip

  3. They also maintain the posture 

  4. They prevent capsular impingement of the capsule of the hip joint.

FAQs (Frequently Asked Questions)

1. What are the Principle Function of Gluteus Muscle?

Ans- The main function of the gluteus muscle is, extension, abduction of the hip joint. It also performs internal as well as external rotation of the hip joint. It also helps to provide support to the knee joint.

2. Which Muscles are Called Buttock Muscles?

Ans- The gluteus muscles area fan called buttock muscle primarily constitute the hip of the human body.

3. Which is the Largest Gluteal Muscle?

Ans- Gluteus maximus is the largest among all three gluteal muscles.