Knee-Injury - explained in PalmerProject-Ski- and Snowboard-Lexicon
"The knee is the lower extremity joint connecting the femur, fibula, patella, and the tibia.[1] Since in humans the knee supports nearly the entire weight of the body, it is the joint most vulnerable both to acute injury and to the development of osteoarthritis. Upon birth, a baby will not have a conventional knee cap, but a growth formed of cartilage. In human females this turns to a normal bone knee cap by the age of 3, in males the age of 5.
The knee is a complex, compound, condyloid variety of a synovial joint which hovers. It actually comprises two separate joints.
* The femoro-patellar joint consists of the patella, or ""kneecap"", a so-called sesamoid bone which sits within the tendon of the anterior thigh muscle (m. quadriceps femoris), and the patellar groove on the front of the femur through which it slides.
* The femoro-tibial joint links the femur, or thigh bone, with the tibia, the main bone of the (lower) leg. The joint is bathed in a viscous (synovial) fluid which is contained inside the ""synovial"" membrane, or joint capsule.
The recess behind the knee is called the popliteal fossa. It can also be called a ""knee pit."""