Knee Pain
The knee is the largest joint in the body, and one of the most easily injured. It is made up of the lower end of the thighbone (femur), which rotates on the upper end of the shinbone (tibia), and the knee cap (patella), which slides in a groove on the end of the femur.
The knee also contains large ligaments, which help control motion by connecting bones and by bracing the joint against abnormal types of motion. Another important structure, the meniscus, is a wedge of soft cartilage between the femur and tibia that serves to cushion the knee and helps it absorb shock during motion.
Common Knee Injuries
Knee pain can be the result of local knee problems, including continual wear and stress on the knee joint, as well as injury or a sudden movement that strains the knee. Below are a few of the more common causes:
• Sprained or strained knee ligaments and/or muscles
A sprained or strained knee ligament or muscle is usually caused by a trauma to the knee or a sudden movement (usually twisting) of the knee. Symptoms often include pain, swelling, and difficulty in walking.
Many athletes experience injuries to their knee ligaments. Of the four major ligaments found in the knee, the anterior cruciate ligament (ACL) and the medial collateral ligament (MCL) are often injured in sports. The posterior cruciate ligament (PCL) may also be injured.
ACL injury
Changing direction rapidly, slowing down when running, and landing from a jump may cause tears in the ACL. Athletes who participate in skiing and basketball, and athletes who wear cleats, such as football players, are susceptible to ACL injuries.
MCL injury
Injuries to the MCL are usually caused by a direct blow to the outside of the knee. These types of injuries often occur in contact sports, such as football or soccer.
PCL injury
The PCL is often injured when an athlete receives a blow to the front of the knee or makes a simple misstep on the playing field.
• Torn cartilage
Trauma to the knee can tear the menisci (pads of tissue that act as shock absorbers between the two large bones). Any compression and/or twisting movement can cause pain, plus “locking” of the knee occurs. The mensicus is a tough, rubbery cartilage that is attached to the knee's ligaments. The meniscus acts like a shock absorber. In athletic activities, tears in the meniscus can occur when twisting, cutting, pivoting, decelerating, or being tackled. Direct contact is often involved.
• Tendonitis
Inflammation of the tendons resulting from overuse of the tendon during certain activities such as running, jumping, or cycling.
• Arthritis
Osteoarthritis is the most common type of arthritis that affects the knee
(click here to view article on Arthritis), particularly if there is excessive weight on the joint for a period of time (i.e. being overweight).
Rheumatoid arthritis (click here to view article on Arthritis) can also affect the knees by causing the joint to become inflamed and by destroying the knee cartilage.
However, apart from the local knee problems, generally speaking knee pain is usually a result of problems in areas above and/or below the knee, i.e. the hip, pelvis or foot. For example, an over-pronated foot (fallen arch) causes the whole leg to rotate abnormally, which, over time can lead to pain in the knee through a developed stress pattern.
Where conditions are named in this site it is either because there is research into that particular condition, or to serve to illustrate the kinds of symptoms which might respond to treatment.