By Jon Stiffler, PTA/Sports Center Manager
The Knee Joint
The knee joint is a hinge joint between the tibia, fibula and femur bones. The patella, or knee cap, articulates with the trochlear groove on the end of the femur. At birth, a baby’s “knee cap” will not appear the same as an adult knee cap. The patella is a sesamoid bone that hardens from cartilage to bone at about 3 to 5 years of age. Four basic ligaments give the knee most of its structural stability. Those ligaments are the anterior cruciate ligament, posterior cruciate ligament, medial collateral ligament, and lateral collateral ligament.
The cruciate ligaments are located in the center of the knee joint and provide front to back stability. The collateral ligaments are located one on the inside of the knee and one on the outside of the knee. These ligaments provide side to side stability. Located on top of the tibia are two pieces of cartilage known as the medial and lateral meniscus. The menisci provide for shock absorption, stability, and protecting the ends of the bones from rubbing together.