Meniscal Tears
One of the most common knee injuries, meniscal tears are often the result of twisting or rotating the knee. Meniscal tears can cause symptoms of pain, swelling, and stiffness. They can restrict knee motion.
Other symptoms include popping sensations or feeling like your knee is locked in place when you try to move it.
PCL Tear
The posterior cruciate ligament (PCL) is another ligament in the knee, running along the back and connecting the thighs and lower legs.
While PCL tears can happen to anyone, they are especially common amongst athletes who ski or play baseball, football, or soccer.
ACL Tear
The anterior cruciate ligament (ACL) is one of the four main ligaments connecting both of the bones in the knee. A partial or complete tear of the ACL can result from an injury or an overextension of the joint.
Symptoms can include pain, feelings of instability, and difficulty carrying on with the sport or activity where you sustained the injury.
Arthritis
Arthritis is a condition that affects the joints throughout the body, causing pain and stiffness. As a result, one of the most common spots for arthritic pain is the knees.
Although there are around 100 types of arthritis, arthritis in the knee typically is a result of osteoarthritis, post-traumatic arthritis, or rheumatoid arthritis.
Risk factors or causes for arthritis of the knee can include age, bone anomalies, injuries, stress, weight, or gout.
Patellar Instability
Patellar instability occurs when the kneecap (patella) moves out of the groove that holds it in place. This can further lead to partial or complete dislocation of the kneecap.
Conditions like cerebral palsy, down syndrome, or Ehlers-Danlos syndrome may make a person more likely to develop patellar instability.