Vastus intermedius muscle

Vastus intermedius muscle
Muscles of lower extremity
Gray's	subject #128 471
Origin	antero/ lateral femur
Insertion	patellar ligament
Artery	femoral artery
Nerve	femoral nerve
Actions	extends leg

The Vastus intermedius (Cruraeus) arises from the front and lateral surfaces of the body of the femur in its upper two-thirds, sitting under Rectus Femoris and from the lower part of the lateral intermuscular septum. Its fibers end in a superficial aponeurosis, which forms the deep part of the Quadriceps femoris tendon.

The Vastus medialis and Vastus intermedius appear to be inseparably united, but when the Rectus femoris has been reflected^{[when defined as?]} a narrow interval will be observed extending upward from the medial border of the patella between the two muscles, and the separation may be continued as far as the lower part of the intertrochanteric line, where, however, the two muscles are frequently continuous.

Due to being the deeper middle-most of the quadriceps muscle group, the intermedius is the most difficult to stretch once maximum knee flexion is attained. It cannot be further stretched by hip extension as the rectus femoris can, nor is it accessible to manipulate with massage therapy to stretch the fibres sideways as the vastus lateralis and vastus medialis are.

Additional images

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  Right femur. Anterior surface.

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  Right femur. Posterior surface.

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  Muscles of the iliac and anterior femoral regions.

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  Cross-section through the middle of the thigh.

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  Cross section through thigh.

External links

• LUC vasi
• Cross section at UV pembody/body18b
• PTCentral

This article was originally based on an entry from a public domain edition of Gray's Anatomy. As such, some of the information contained within it may be outdated.