The patella, or kneecap, is one of three bones, along with the tibia (shin bone) and femur (thigh bone), that make up the knee joint. All of these bones are covered with a layer of cartilage at points where their surfaces come into contact. Furthermore, the patella is wrapped up inside a tendon. This tendon connects the quadriceps muscle of the thigh to the shin bone (tibia) below the knee joint.
The patella is important functionally because it increases the leverage of the knee joint. From a mechanical perspective, the patella allows for an increase of about 30% in strength of extension (kicking) of the leg at the knee joint.
The most common symptom of patellar irritation is pain associated with prolonged sitting and descending stairs. The reason the pain is more severe when descending stairs rather than climbing is due to the mechanics of the knee joint. The basic explanation is that the force burdened by the patella is about two times body weight when climbing up stairs, and seven times body weight when descending. This increased burden on the kneecap when going down stairs causes a magnification of pain during that activity.
There are several common problems associated with the patella that can cause problems and pain in the knee. For more information, follow the links to the following resources:
Chondromalacia Patellae (Runner's Knee)
The most common disorder is known as chondromalacia patellae, often called Runner's Knee. Chondromalacia occurs because of irritation of the articular cartilage on the undersurface of the kneecap.
Prepatellar Bursitis (Housemaid's Knee)
Prepatellar bursitis, or Housemaid's Knee Syndrome, is a condition of swelling and inflammation over the front of the knee. This is commonly seen in patients who kneel for extended periods, such as carpet layers and gardeners.
Patellar Subluxation/Dislocation
Also called an unstable kneecap, patients who experience this painful knee condition have a patella that does not track evenly within its groove on the femur.
Treatment of these various kneecap conditions depends on the diagnosis, however there are some general guidelines that can be followed. For more information, and for a diagnosis of your knee pain, it is important to see your doctor.
- Rest
Resting the injured knee to allow time for inflammation to subside is very important. Cross-training will allow you to keep in shape. When you do return to activity, do so gradually. - Physical Therapy
Physical therapy is very important to balance the strength of the muscles around the knee joint. Most importantly, the quad and hamstring muscle groups should be flexible and balanced. - Ice the Injury
Apply ice to the knee to cool down inflammation in stimulate blood flow to the area. Be careful not to ice too much! - Anti-Inflammatory Medications
Anti-inflammatory medications may help with inflammation and will also help alleviate some of the pain associated with patella conditions. - Arthroscopic Surgery
While surgery is seldom needed because of a kneecap problem, arthroscopy is a treatment option if the problem is not getting any better with conservative treatment.
The images in this article were generously provided by Medical Multimedia Group, Inc.
