Knee Joint (Cross-section View)

The knee joint is a relatively complex anatomical structure. In addition to a variety of ligaments to maintain stability and the presence of large muscle groups, internally, it is a classic example of a synovial joint. Both the femur and tibia are enclosed in a joint capsule lined with synovial tissue. Between the condyles of the femur and the condylar surface of the tibia are menisci, which serve as shock absorbers for the knee joint, located medially and laterally inside the joint. Between...

Anatomy Explorer

Full Knee Joint (Cross-section View) Description

[Continued from above] . . . each muscle group are fluid-filled sacs called bursa and the presence of fat bodies named for their location, which reduce friction and lend added protection to the joint capsule.

The patella is the technical name for the kneecap, the triangular-shaped bone at the front of the knee joint. The patellar ligament is the center of the common tendon, which continues from the patella (knee cap) to the tibia. It is a very strong, flat band, the fibers of which are continuous over the front of the patella with tendons that extend and pass down the sides of the patella into the extremity of the tibia along the sides of its rounded prominence. It is separated from the joint by a large padding of fat. A medial patellar retinaculum, or canal, in the patella allows muscle and tissue to pass through from the femur (thigh bone).

During normal activity such as walking or running, and even for support while standing, the knee will function superbly. It can tolerate moderate stress without significant injury. However, the knee lacks support to withstand many types of injury, especially rotational forces such as those seen in many athletic activities. Knee injuries, even though minor, may require surgery, and if they involve the cartilage, may have delayed healing time due to a lack of blood supply to the cartilage.