Why does the biceps femoris have two heads?
Both heads of the biceps femoris perform knee flexion. Since the long head originates in the pelvis it is involved in hip extension. The long head of the biceps femoris is a weaker knee flexor when the hip is extended (because of active insufficiency).
How is the bicep femoris named?
The biceps femoris muscle of the leg derives its name from having two heads of origin, long and short. The long head arises from the medial facet on the ischial tuberosity in continuity with the tendon of origin of semitendinosus.
Is biceps femoris 2 joint muscle?
Together with the semitendinosus and semimembranosus muscles, it makes the group of muscles commonly known as the hamstrings. Biceps femoris muscle runs from the ischial tuberosity, all the way to the proximal part of the fibula. In doing so the muscle crosses two joints; the hip joint and the knee joint.
Where is the biceps femoris long head?
The biceps femoris muscle, located in the posterior portion of the thigh, is composed of a long head that originates from the ischial tuberosity and a short head that originates at the linea aspera of the femur. The biceps femoris inserts at the lateral head of the fibula.
What is the biceps femoris?
Description. Biceps femoris is a muscle of the posterior compartment of the thigh, and lies in the posterolateral aspect. It arises proximally by two ‘heads’, termed the ‘long head’ (superficial) and the ‘short head’ (deep). It is part of the hamstrings.
What is biceps femoris?
The biceps femoris is one of the hamstring muscles at the back of the thigh. It originates in two places: the ischium (lower, rear portion of the pelvis, or hipbone) and the back of the femur (thighbone).
What does the short head of the biceps femoris do?
Flexes the leg at the knee; laterally rotates leg when the knee is flexed.
What shape is biceps femoris?
spindle-shaped muscle
The biceps femoris is a two-part spindle-shaped muscle. It has two heads: the long head and the short head. The two heads have different sites of origin and are innervated by different nerves, but they join together distally, inserting at the same location.
Where is the Bipennate located?
A type of pennate muscle wherein the muscle fibers or fascicles are in opposite sides of the central tendon. Example of bipennate muscle is rectus femoris.
Is biceps femoris skeletal?
The biceps femoris is a double-headed muscle located on the back of 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.
Where does the short head of biceps femoris insertion?
Biceps Femoris – Short Head
- Origin: Lateral lip of linea aspera, lateral supracondylar ridge of femur, and lateral intermuscular septum of thigh.
- Insertion: Primarily on fibular head; also on lateral collateral ligament and lateral tibial condyle.
What is the head of the biceps femoris?
Biceps femoris is a muscle of the posterior compartment of the thigh, and lies in the posterolateral aspect. It arises proximally by two ‘heads’, termed the ‘long head’ (superficial) and the ‘short head’ (deep). It is part of the hamstrings. Short head: linea aspera and lateral supracondylar line of the femur
What is the aponeurotic sheet of the biceps femoris?
Near the muscle’s insertion, the long head of biceps femoris continues as an aponeurosis. The muscle fibers from the short head join the aponeurotic sheet, comprising the round common tendon that inserts to the lateral aspect of the head of the fibula.
Where does the biceps femoris tendon insert?
A tendon called the biceps femoris tendon is formed by the long head and short head by coming together at the distal thigh. This tendon inserts onto the lateral side of the head of the fibula and the lateral condyle of the tibia.
What is the blood supply to the biceps femoris?
The majority of the blood supply for biceps femoris comes from branches of the deep femoral artery (perforating arteries and medial circumflex femoral artery). Additional supply comes from the inferior gluteal and superior lateral genicular arteries. In general, the biceps femoris muscle acts on both the knee and hip joints.