The rectus femoris is the only quadriceps head that crosses the hip joint, arising from the anterior inferior iliac spine and running straight down the anterior thigh to the patella. Its biarticular nature means it is length-dependent, becoming mechanically disadvantaged in positions of hip extension and knee flexion simultaneously, which limits its effectiveness as both a hip flexor and knee extensor in those ranges.
| Origin | Anterior inferior iliac spine (AIIS); Groove above the acetabular rim |
|---|---|
| Insertion | Base of the patella and patellar tendon to the tibial tuberosity |
| Nerve Supply | Femoral nerve (L2, L3, L4) |
| Blood Supply | Lateral circumflex femoral artery |
| Actions |
|
|---|
Its dual-joint function means that full hip extension stretches and reduces its knee extension torque, explaining why quadriceps strength tests should be performed with the hip in neutral rather than flexed position to avoid underestimating the other quadriceps heads.
The rectus femoris is the most commonly strained quadriceps muscle, typically at the proximal musculotendinous junction during kicking or sprinting. AIIS avulsion fractures at its origin are seen in adolescent athletes. The two-joint nature of the rectus femoris is clinically assessed by the Thomas test and the Ely test, where limited prone knee flexion combined with spontaneous hip flexion indicates rectus femoris tightness.
The rectus femoris runs centrally down the anterior thigh as the most superficial quadriceps head and is the easiest to palpate, becoming firm during resisted knee extension or hip flexion with the knee extended.
Proximal musculotendinous junction tear from explosive kicking or sprinting, producing anterior hip and proximal thigh pain with a palpable defect in severe cases.
Avulsion of the anterior inferior iliac spine at the rectus femoris origin in adolescent athletes during explosive sprinting, producing acute anterior hip pain with imaging showing the detached apophysis.
This website uses cookies to enhance your experience. Some are essential for site functionality, while others help us analyze and improve your usage experience. Please review your options and make your choice.
If you are under 16 years old, please ensure that you have received consent from your parent or guardian for any non-essential cookies.
Your privacy is important to us. You can adjust your cookie settings at any time. For more information about how we use data, please read our privacy policy. You may change your preferences at any time by clicking on the settings button below.
Note that if you choose to disable some types of cookies, it may impact your experience of the site and the services we are able to offer.
Some required resources have been blocked, which can affect third-party services and may cause the site to not function properly.
This website uses cookies to enhance your browsing experience and ensure the site functions properly. By continuing to use this site, you acknowledge and accept our use of cookies.
