The articularis genus (also known as the subcrureus muscle) is a small

skeletal muscle Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscl ...

located anteriorly on the

thigh In human anatomy, the thigh is the area between the hip (pelvis) and the knee. Anatomically, it is part of the lower limb. The single bone in the thigh is called the femur. This bone is very thick and strong (due to the high proportion of bone ...

just above the

knee In humans and other primates, the knee joins the thigh with the leg and consists of two joints: one between the femur and tibia (tibiofemoral joint), and one between the femur and patella (patellofemoral joint). It is the largest joint in the hu ...

Structure

It arises from the anterior surface of the lower part of the body of the femur, deep to the

vastus intermedius The vastus intermedius () (Cruraeus) arises from the front and lateral surfaces of the body of the femur in its upper two-thirds, sitting under the rectus femoris muscle and from the lower part of the lateral intermuscular septum. Its fibers en ...

, close to the knee and from the deep fibers of the vastus intermedius. Its insertion is on the

synovial membrane The synovial membrane (also known as the synovial stratum, synovium or stratum synoviale) is a specialized connective tissue that lines the inner surface of capsules of synovial joints and tendon sheath. It makes direct contact with the fibrous ...

of the knee-joint.

Blood supply

It is supplied by the

lateral femoral circumflex artery The lateral circumflex femoral artery, also known as the lateral femoral circumflex artery, or the external circumflex artery, is an artery in the upper thigh. It is usually a branch of the profunda femoris artery, and produces three branches. It ...

Innervation

It is innervated by branches of the

femoral nerve The femoral nerve is a nerve in the thigh that supplies skin on the upper thigh and inner leg, and the muscles that extend the knee. Structure The femoral nerve is the major nerve supplying the anterior compartment of the thigh. It is the largest ...

(L2-L4).

Variation

Flat, wispy and highly variable, sometimes consisting of several separate muscular bundles, this muscle is without a distinct investing fascia and ranges 1.5–3 cm in width. It is usually distinct from the vastus intermedius, but occasionally blended with it.

Function

Articularis genus pulls the

suprapatellar bursa The knee bursae are the fluid-filled sacs and synovial pockets that surround and sometimes communicate with the knee joint cavity. The bursae are thin-walled, and filled with synovial fluid. They represent the weak point of the joint, but also pr ...

superiorly during extension of the knee, and prevents impingement of the synovial membrane between the

patella The patella, also known as the kneecap, is a flat, rounded triangular bone which articulates with the femur (thigh bone) and covers and protects the anterior articular surface of the knee joint. The patella is found in many tetrapods, such as m ...

and the

femur The femur (; ), or thigh bone, is the proximal bone of the hindlimb in tetrapod vertebrates. The head of the femur articulates with the acetabulum in the pelvic bone forming the hip joint, while the distal part of the femur articulates with ...

References

External links

* ''Farshchian's Orthopedic Regenerative Series: The Knee
Articularis Genus
' (very clear illustration) {{Authority control Muscles of the lower limb