Muscles of the Thigh

These vocabulary flashcards cover the anatomical compartments, specific muscles, origins, insertions, and functional movements of the thigh as discussed in lecture 8.3.

Thigh Compartments

The three sections (anterior, medial, and posterior) that separate the muscles of the thigh.

Hip Flexion

Movement involving muscles on the anterior compartment lifting the leg towards the anterior at the acetabulofemoral joint.

Hip Extension

Movement involving muscles on the posterior aspect bringing the leg posteriorly.

Hip Abduction

The movement of pulling the leg away from the midline on the coronal plane using the anteroposterior axis of rotation.

Hip Adduction

Movement involving muscles of the medial thigh pulling the limb in towards the midline.

Anterior Compartment Primary Actions

Commonly responsible for hip flexion and knee extension.

Medial Compartment Primary Actions

Primarily responsible for adduction at the acetabulofemoral joint.

Posterior Compartment Primary Actions

Primarily responsible for flexing the knee and extending the hip.

Pectineus

An anterior compartment muscle originating from the pectineal line of the pubic bone and inserting into the pectineal line of the femur; it flexes and externally rotates the hip.

Psoas major and iliacus

Muscles that originate from the lower thoracic/lumbar vertebrae and iliac fossa, respectively, and share a common insertion at the lesser trochanter.

Sartorius

The longest muscle in the human body; it originates from the anterior superior iliac spine (ASIS) and inserts distal to the knee on the medial aspect of the tibia.

Sartorius (Unique Action)

The only muscle in the anterior compartment that flexes both the hip and the knee.

Rectus femoris

The most superficial quadriceps muscle; it originates at the anterior inferior iliac spine (AIIS) and inserts into the patella and tibial tuberosity.

Vastus lateralis

A large quadriceps muscle on the lateral side that originates from the greater trochanter and the length of the linea aspera.

Vastus intermedius

A quadriceps muscle deep to the rectus femoris that originates on the anterior and lateral aspect of the femoral shaft.

Vastus medialis

A quadriceps muscle on the medial side originating from the intertrochanteric line and the linea aspera.

Adductor brevis

The shortest adductor muscle originating from the inferior pubic rami/ischial pubic ramus and inserting into the linea aspera of the posterior femur.

Adductor longus

An adductor muscle sitting superficial to the adductor brevis that originates from the pubic bone and inserts into the linea aspera.

Adductor magnus

The largest adductor muscle; it originates from the ischial pubic ramus and ischial tuberosity and contains an opening called the adductor hiatus.

Adductor hiatus

The landmark through which the femoral artery passes to become the popliteal artery as it moves into the posterior side of the knee.

Gracilis

The smallest but longest muscle of the medial thigh; it originates near the pubic symphysis and inserts medial to the tibial tuberosity.

Biceps femoris

A lateral hamstring muscle with two heads; the long head originates at the ischial tuberosity, while the short head originates from the femoral shaft.

Semimembranosus

A deep, flat muscle of the posterior medial thigh that originates from the ischial tuberosity and inserts onto the medial aspect of the tibia.

Semitendinosus

A superficial posterior medial muscle with a small belly and long tendon; it extends the hip and flexes the knee.

Closed packed position

A passive process in full knee extension where the tibia laterally rotates underneath the femur to lock the joint in place.

Popliteus muscle

A small oblique muscle that unlocks the knee from the closed packed position by medially rotating the tibia.