The knee, the largest joint in the body, is vulnerable to a variety of problems. Overuse, the way the joint is structured and other factors may lead to conditions such as arthritis or tendonitis, but taking preventable steps can reduce risk.

Knee parts: The patella (kneecap) is held in place by four ligaments — the ACL (front), PCL (back), LCL (outer) and MCL (inner), which give strength and stability to the joint. High impact activities — jumping, sudden changes in direction and frequent stops and starts — are hard on the knees and can result in torn ligaments or cartilage. If you are unaccustomed to regular exercise, it is important to build strength and stamina gradually and listen to your body.

Cracking and popping: With movement, ligaments and tendons slide over bones, which may create cracking or popping noises in the knees, without any pain. This is not uncommon and most of the time is nothing to be concerned about.

Out of alignment: Sometimes, the patella may be slightly out of alignment, which may rub on surrounding soft tissues. If noises are associated with pain or there is swelling, tenderness or burning, this should be evaluated by a physician. Arthritis may also cause cracking or grinding noises, which can usually be re-created by moving the affected joint.

Inflammation: Tendonitis refers to inflammation of a tendon. Repetitive motion (overuse/overtraining) is a major cause of tendonitis, and if not addressed it can lead to rupture/tearing of the tendon. Symptoms of tendonitis may include tenderness, and pain felt during high impact activities such as running or jumping.

Other trauma: Chondromalacia is a softening of the surface on the underside of the kneecap. This condition can occur from trauma, overuse, improper exercise technique, poor alignment of the joint, or muscle imbalances. Symptoms include dull pain around or under the kneecap that increases when walking down stairs, or it may be painful with stair climbing or other forms of weight bearing exercise.

More tips to help avoid knee problems: Maintain a healthy weight. Posture and gait are important to the health of knee joints and can be helped by wearing the right shoes.

— Marjie Gilliam, Cox Newspapers