Knee Joint Research Paper

The knee joint is formed by the articulation of the distal end of the femur and the proximal end of the tibia. The fibula is only involved to the extent that it serves as an attachment site for connective tissue. In this paper, the anatomy of the joint will be discussed.

The knee is a hinge-type, diarthrotic, or freely moveable joint. Also referred to as a synovial joint, the 2 articulating ends of bone are encased in a capsule that lubricates the joint with synovial fluid to reduce friction.

Each bone in a synovial joint has articular cartilage at the articulating surface. The C-shaped medial and lateral menisci serve to deepen the articulation at the superior surface of the tibia, thus enhancing the bony stability of the joint.
The medial and lateral collateral ligaments have a stabilizing effect in a lateral plane of motion, helping to prevent sideward displacement and over-rotation. The medial collateral attaches the femur to the tibia, also attaching to the medial meniscus. The lateral collateral attaches the femur to the fibula but has no attachment to the lateral meniscus. Both collaterals lie slightly posterior to the lateral axis of the knee joint and are taut when the knee is full extension. This positioning of the ligaments causes a slackness when flexion occurs, allowing medial and lateral rotation to take
The extensors of the knee are the quadriceps group. The quads include the rectus femoris, and the vastus lateralis, intermedius, and medialis. This muscle group shares a common tendon at insertion. The patellar tendon inserts at the tibial tuberosity, and within this tendon lies the patella. The patella is anterior to the femur-tibia articulation, and this sesmoid bone increases the leverage of the quads by acting as a pulley. The major contributor to the stability of the knee joint is the strength of the quads. The only muscle that assists in extension is the tensor fascia