Fractures of the bones of knee are relatively common. The patella, or kneecap, may fracture due to a fall directly onto it or in car accidents, when the knee is driven into the dashboard. If the bone is pulled apart, surgery will be required for repair, but if the bone is in good position, a knee immobilizer and watchful waiting may be all that is required.
The head of the fibula on the lateral side of the knee joint can be fractured either by a direct blow or as part of an injury to the shin or ankle. This bone usually heals with little intervention, but fractures of this bone can have a majorcomplication. The peroneal nerve wraps around the bone and can be damaged by the fracture. This will cause a foot drop, so do not be surprised if the physician examines your foot when you complain of knee problems.
With jumping injuries, the surface of the tibia can be damaged, resulting in a fracture to the tibial plateau. Since this is where the femoral condyle sits to move the knee joint, it is important that it heals in the best position possible. For that reason, after plain X-rays reveal this fracture, a CT scan is done to make certain that there is no displacement of the bones. Occasionally, this type of fracture requires surgery for repair.
Fractures of the femur require significant force, but in people with osteoporosis, less force is needed to cause a fracture of this large bone. In people with knee replacements who fall, there is a potential weakness at the site of the knee replacement above the femoral condyle, and this can be a site of fracture. The decision to operate or treat by immobilization with a cast will be made by theorthopedist.
Housemaid’s knee (prepatellar bursitis) is due to repetitive kneeling and crawling on the knees. The bursa or space between the skin and kneecap becomes inflamed and fills with fluid. It is a localized injury and does not involve the knee itself. Treatment includes padding the knee and using ibuprofen as an anti-inflammatory medication. This injury is commonly seen in carpet installers and roofers.
The kneecap sits within the tendon of the quadriceps muscle, in front of the femur, just above the knee joint. It is held in place by the muscles of the knee.
The patella can dislocate laterally (toward the outside of the knee). This occurs more commonly in women because of anatomic differences in the angle aligning the femur and tibia. Fortunately, the dislocation is easily returned to the normal position by straightening out the knee, usually resulting in the kneecap popping into place. Physical therapy for muscle strengthening may be needed to prevent recurrent dislocations.
Patello-femoral syndrome occurs when the underside of the patella becomes inflamed if irritation develops as it rides its path with each flexion and extension of the knee, and it does not track smoothly. This inflammation can cause localized pain, especially with walking down stairs and with running. Treatment includes ice, anti-inflammatory medication, and exercises to balance the quadriceps muscle. More severe cases may require arthroscopic surgery to remove some of the inflamed cartilage and realign parts of the quadriceps muscle.