The knee is the largest joint in the body; it is formed by the lower end of the femur, the upper end of the tibia and the kneecap. The ends where these three bones make contact are covered with cartilage, a smooth substance that protects bones and allows them to move easily. The articular menisci are located between the femur and the tibia. These C-shaped wedges act as “shock absorbers” which quilt the joint. Long ligaments hold the femur and tibia together and provide stability. The long thigh muscles give the knee strength. All other knee surfaces are covered by a thin lining called synovial membrane. This membrane releases a fluid that lubricates the cartilage, reducing friction to almost zero in a healthy knee. Normally, all these components work in harmony. But disease or injury can distort this harmony, resulting in pain, muscle weakness and reduced function.
1. Knee Replacement:
It is a surgical procedure to replace the articular surfaces of the knee for an artificial surface. To coat the end of a worn femur, few cuts are made in the cartilage to place a metal component. Then, after making some appropriate cuts, a component with a metal part and one made of high density plastic (polyethylene) are placed in the tibia, and if required, a plastic button is placed in the patella. To achieve faster component fixation, bone cement (methylmethacrylate) is typically used to seal them in place.
The meniscus is a fibro-cartilage located between the femur and the tibia. It is a structure that follows the femur and the tibia in the flexion-extension and rotational movements of the knee. It serves to make the knee more consistent, supports knee stability, and protects the articular cartilage of the tibia and the femur by better distributing the burden of the body weight.
There are two categories of meniscus injuries, acute (caused by trauma) or degenerative (caused by aging). Meniscus injury symptoms are pain when performing certain positions, painful limitation of knee motion, tear, lack of strength, and crackling or popping sounds.
Trauma to the knee ligament can be severe and usually occurs during a sports activity. The ACL is reconstructed through arthroscopy using the body’s own tendons. The remnant of the torn ACL is removed, a tunnel is made at the tibial and femoral level and the new ligament is passed through them. This is fixed by special screws. This type of surgery and graft fixation allows fast rehabilitation, which allows patients to return to their pre-injury sports level.
After surgery, the patient initiates a structured rehabilitation program. Patient engagement and adequate participation are essential for a good functional outcome. The specific exercises of the program and deadlines vary depending on the graft that is used and the surgical repair associated with other knee structures.
The kneecap is a thick triangular bone that protects the front of the knee joint and acts as a fulcrum, providing increased power to the thigh muscles, which extend the knee. When a kneecap brakes or is displaced, bone pieces have moved out of place.
A traffic accident, sports injuries or a sharp fall on your knee can cause patellar fracture. But factors such as advanced age, osteoporosis, post-menopause, reduced muscle mass and obesity may increase the risk of developing a patellar or kneecap fracture.