Pelvis/Thigh & Leg Muscles (Test #3)

Iliopsoas

A fused muscle composed of two muscles: iliacus & psoas major. It runs from the iliac bone and lower vertebrae deep inside the pelvis to insert on the lesser trochanter of the femur. It aids in hip flexion and acts to keep the upper body from falling backward when we are standing erect.

Rectus femoris

A muscle in the quadriceps, this muscle is attached to the hip and helps to extend or raise the knee. This muscle is also used to flex the thigh. This muscle is the only muscle that can flex the hip.

Fibularis longus

A muscle inside the outer area of the leg, which everts (bends in an outward direction) and flexes the ankle. The muscle is attached to the head of the fibula and is controlled by the fibular nerve. It runs the length of the fibula and eventually turns into a tendon

Gastrocnemius

A two-bellied muscle that forms the curve of the calf of the posterior leg. It is called the "toe-dancer's" muscle because it is a mover for plantar flexion of the foot.

Soleus

Deep to the gastrocnemius is this fleshy muscle. It arises on the tibia and fibula and inserts into the calcaneal tendon and is a strong plantar flexor of the foot.

Adductor Muscle

Form the muscle mass at the medial side of each thigh. They press the thighs together. Their origins are on the pelvis and insert on the proximal aspect of the femur.

Iliotibial tract

It is a thick strip of connective tissue connecting several muscles in the lateral thigh. It plays an important role in the movement of the thigh by connecting hip muscles to the tibia of the lower leg.

Sartorius

It is a thin, straplike muscle. It is the most superficial muscle of the thigh. It runs obliquely across the thigh from the anterior iliac crest to the medial side of the tibia. It aids in bringing the legs to a crossed position.

Gracilis

One of the muscles found in the groin. It starts at the pubic bone and extends down to the upper medial shaft of the tibia. It is responsible for hip adduction and assists knee flexion.

Biceps femoris

One of the three muscles that make up the hamstring. It is a double-headed muscle located on the back of the thigh. It consists of two parts: the long head, attached to the ischium (the lower and back part of the hip bone), and the short head, which is attached to the femur bone. This muscle is important for knee flexion, internal and external rotation, and hip extension.

Semimembranosus

One of the three muscles that make up the hamstring. It is found on the back of the thigh and runs from the base of the pelvis to the back of the tibia. This muscle is attached to the pelvis and tibia via tendons. The muscle has several functions, including enabling the leg to flex and rotate, and serving as a thigh extensor.

Semitendinosus

One of the three muscles that make up the hamstring. This muscle begins at the inner surface of the base of the pelvis and the sacrotuberous ligament. It inserts at the medial tibial condyle. It is the middle hamstring muscle that aids in flexing the knee and extend the hip.

Calcaneal tendon (Achilles tendon)

This is a posterior leg tendon — a fibrous connective tissue that joins muscles in the back of the leg. It is formed when the soleus muscle tendon joins with the gastrocnemius tendon.

Vastus medialis

This muscle is a part of the quadriceps muscle group, located on the front of the thigh. It is the most medial, or inner, of the quadriceps muscles. It extends the entire length of the thigh. This muscle is used to extend the leg at the knee and to stabilize the patella,

Extensor digitorum longus

This muscle is located at the front of the leg and is adjacent to the peroneus brevis muscle and the tibialis anterior muscle. This wing-shaped muscle works to extend the foot at the ankle, along with the four smallest toes.

Vastus lateralis

This muscle is located on the side of the thigh. This muscle is the largest of the quadriceps group (often called quads) which also includes the rectus femoris, the vastus intermedius, and the vastus medialis. Collectively, the quadriceps muscle is the largest in the human body and its purpose is to extend the knee. The specific task of this muscle is to extend the lower leg and allow the body to rise up from a squatting position.

Tibialis anterior

This muscle is the largest muscle located in the anterior compartment of the leg. In general, muscles of this compartment help to flex the foot in an upward direction at the ankle and also extend the toes.