Knee pain can be caused by various factors such as injuries (such as injury to ligaments, cartilage or meniscus, bones, bursa and tendons, that are related to knee joint), mechanical problems, various types of arthritis that affect knees, and some other problems.
Injuries that can cause knee pain:
- Injury to ACL (anterior cruciate ligament): injury usually results in tearing of the ligament. Injury to ACL (it is one of the four ligaments that connect/joins the shinbone or tibia with thighbone or femur) is the commonest type of ligament injury. Injury to ACL is common among players who play basketball, football etc. that need sudden change in direction during playing.
- Torn meniscus: Meniscus is tough rubbery cartilage that acts as shock absorber between femur (upper body) and tibia (below knee area). Meniscal tear can occur during weight bearing, if you turn suddenly.
- Bone fracture: bones of knee joint (patella, lower end of femur and upper end of tibia) may be fractured in motor vehicle accident or similar other accidents. Fracture may also occur if you suffer from osteoporosis and your bones are weak.
- Knee bursitis: bursae (the small sacs of fluid that are present outside knee joint and help in smooth gliding of tendons and ligaments over knee joint) can become inflamed and cause bursitis.
- Tendons that are attached to bones near knee joint may become inflamed and cause tendinitis. Runners, cyclists, skiers and other similar sportspersons are at greater risk of developing tendinitis.
Mechanical problems that can cause knee pain:
- Loose body: a small fragment of bone or cartilage/meniscus may break off due to injury or degeneration and may float in the joint sp[ace of knee joint causing knee pain. Some people may not face any problem even if there is loose body in the knee joint unless it interfere with knee movements.
- Patellar dislocation may occur and may slip away from knee joint causing pain, due to accidents or some other cause.
- Sometimes there may be pain in knee joint which makes the sufferer change gait to avoid pain. Unfortunately this change in gait causes more damage to the knee and lead to greater pain later.
- Iliotibial band syndrome may occur in long distance runners.
Various types of arthritis that can cause knee pain:
- Osteoarthritis: this is due to wear and tear of joints. As an individual age, the joints erosion may occur due to wear and tear leading to osteoarthritis and knee pain.
- Rheumatoid arthritis: This is a common type and serious type of arthritis and lead to knee pain.
- Gouty arthritis: this occur due to deposition of uric acid crystals in the joint space and cause knee pain as a result.
- Septic arthritis: this occurs due to septicemia spreading to joints and causing arthritis and knee pain.
- Pseudogout: this occur due to presence of calcium containing crystals in joint space, but not typical gout. Knee joint is commonly affected in pseudogout.
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