Q&A

What structures make up the extensor mechanism of the knee joint?

What structures make up the extensor mechanism of the knee joint?

The knee extensor mechanism is a complex structure formed by the quadriceps muscle and tendon, the patella, the patellar tendon and the ligaments that surround and help stabilize the knee.

Where is the extensor mechanism located?

The extensor mechanism of the knee begins above the hip with the origin of the rectus femoris muscle on the anterior inferior iliac spine. The remainder of the quadriceps muscle group, vastus lateralis, vastus intermedius, and vastus medialis originate on the femoral shaft.

What types of conditions can develop in the extensor mechanism?

Danielle Campagne

  • Quadriceps tendon tears.
  • Patellar tendon tears.
  • Patellar fractures.
  • Tibial tubercle fractures.

What is extensor disruption?

The extensor mechanism disruptions include rupture of the quadriceps tendon, patellar fracture, patellar tendon rupture, and tendon avulsion at the tibial tubercle;1-4 the most commonly encountered form of disruption involves rupture of the patellar tendon.

What are the extensor muscles of the knee?

The quadriceps femoris muscle group (rectus femoris, vastus lateralis, vastus medius, and vastus intermedius) crosses the knee via the patella and acts to extend the leg. The hamstring group muscles (semitendinosus, semimembranosus, and biceps femoris) flex the knee and extend the hip.

What is the strong extensor of the knee?

The Quadriceps femoris is the most voluminous muscle of the human body. The quadriceps femoris is a hip flexor and a knee extensor.

How does the extensor mechanism work?

The extensor hoods are triangular aponeuroses by which the extensor tendons insert onto the phalanges. Contraction of the extensor digitorum muscle tightens this tendon which acts on these attachments and extends the fingers.

What is the extensor mechanism finger?

The extensor mechanism of the fingers is divided into topographic zones, which extend from the forearm to the distal phalanx. Extensor tendon injuries and tenosynovitis represent clinical situations in which knowledge of this anatomy is useful for the clinical radiologist.

What is a knee extensor?

Description. The extensor mechanism of the knee comprises the quadriceps muscle and tendon, the patella, and the patellar tendon (also known as the infra-patellar ligament). Disruption of any of these components impedes a person’s ability to actively extend the knee or resist passive flexion.

How do I strengthen my knee extensors?

Sit on a table or desk with your legs hanging freely, and place a thin pad under your knee, so that the knee is slightly higher than the hip. Extend the knee slowly with the foot flexed, until the leg is extended; hold 3-5 seconds, and then lower slowly under control. Do 10 repetitions and repeat with the other leg.

What is extensor reconstruction?

Allograft reconstruction of the extensor mechanism of the knee is an interesting and reliable surgical solution in difficult cases of chronic patellar defect or patellar extensor mechanism disruption. One of the limits of this technique is the availability of grafts.

What is knee Retinaculum?

The medial patellar retinaculum is a tendon of the knee that crosses the knee joint on the medial side of the patella. The medial patellar retinaculum is the branch of the tendon of insertion of the quadriceps femoris that crosses the knee on the medial side of the patella.