The vastus intermedius () (Cruraeus) arises from the front and

lateral Lateral is a geometric term of location which may also refer to: Biology and healthcare * Lateral (anatomy), a term of location meaning "towards the side" * Lateral cricoarytenoid muscle, an intrinsic muscle of the larynx * Lateral release ( ...

surfaces of the body of the femur in its upper two-thirds, sitting under the

rectus femoris muscle The rectus femoris muscle is one of the four quadriceps muscles of the human body. The others are the vastus medialis, the vastus intermedius (deep to the rectus femoris), and the vastus lateralis. All four parts of the quadriceps muscle attach ...

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 The quadriceps femoris muscle (, also called the quadriceps extensor, quadriceps or quads) is a large muscle group that includes the four prevailing muscles on the front of the thigh. It is the sole List of extensors of the human body#Knee, exte ...

tendon. The

vastus medialis The vastus medialis (vastus internus or teardrop muscle) is an extensor muscle located medially in the thigh that extends the knee. The vastus medialis is part of the quadriceps muscle group. Structure The vastus medialis is a muscle presen ...

and vastus intermedius appear to be inseparably united, but when the

rectus femoris The rectus femoris muscle is one of the four quadriceps muscles of the human body. The others are the vastus medialis, the vastus intermedius (deep to the rectus femoris), and the vastus lateralis. All four parts of the quadriceps muscle attach ...

has been reflected during dissection 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 The intertrochanteric line is a line upon the anterior aspect of the proximal end of the femur, extending between the lesser trochanter and the greater trochanter. It is a rough, variable ridge. Structure The intertrochanteric line marks the bound ...

, where, however, the two muscles are frequently continuous. Due to being the deeper middle-most of the

quadriceps The quadriceps femoris muscle (, also called the quadriceps extensor, quadriceps or quads) is a large muscle group that includes the four prevailing muscles on the front of the thigh. It is the sole extensor muscle of the knee, forming a large ...

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

can, nor is it accessible to manipulate with massage therapy to stretch the fibres sideways as the

vastus lateralis The vastus lateralis (), also called the vastus externus, is the largest and most powerful part of the quadriceps femoris, a muscle in the thigh. Together with other muscles of the quadriceps group, it serves to extend the knee joint, moving the ...

and

are.

Additional images

File:Gray244.png, Right femur. Anterior surface. File:Gray245.png, Right femur. Posterior surface. File:Gray430.png, Muscles of the iliac and anterior femoral regions. File:Gray432 color.png, Cross-section through the middle of the thigh. File:Thigh cross section.svg, Cross section through thigh. File:Slide7CCCC.JPG, Vastus intermedius muscle File:Slide9WWWW.JPG, Vastus intermedius muscle File:Slide2EA.JPG, Muscles of thigh. Cross section. File:Slide1DEEA.JPG, Muscles of Thigh. Anterior views.

References

External links

PTCentral
{{Authority control Knee extensors Muscles of the quadriceps Anterior compartment of thigh Muscles of the lower limb