Your knees are composed of bones, muscle, ligaments, cartilage and a cushioning substance that work together to absorb shocks, provide stability and promote smooth functioning of your knees as you use them in activities like walking, running, stooping and climbing stairs. Knee injuries result from mechanical problems, medical conditions, age, weight and injuries, according to MayoClinic.com.
Tendinitis
Tendinitis, which often results from overuse of the knee, occurs when the tendon below the kneecap becomes inflamed or irritated. You might have pain and tenderness in your knee, often in the front of your knee, which worsens when you climb stairs.
Torn Ligament
A torn ligament can cause pain when using the stairs.The anterior cruciate ligament, or ACL, helps to stabilize your knee joint. A torn ACL is a common cause of knee injuries, according to MayoClinic.com.
Torn Cartilage
Torn cartilage can cause your knee to be tender and swollen, and your knee pain worsens after you use the stairs. Small pieces of cartilage or bone can soften or break off of a bone and cause knee-pain, stiffness and popping with movement.
Chondromalacia Patellae
Chondromalicia occurs when the ligament or cartilage under your kneecap knee cap becomes soft due to injury, overuse or muscle weakness. This condition can cause the knee cap and the thighbone to rub together, resulting in pain when you climb the stairs. Symptoms include a tender or swollen knee and your pain may worsen after climbing stairs.
Arthritis
MayoClinic.com lists several types of arthritis that can damage the knee and cause pain during stair climbing. Osteoarthritis causes wear and tear damage to the cartilage in the knee and rheumatoid arthritis affects the joints in the knee joints. Gout, which causes uric acid crystals to build up in the joints, can occur in the knee. Pseudogout, another condition that causes the build up of crystals in the joints, usually affects the knee joint. Septic arthritis results from infection in the knee joint and is often accompanied by fever and pain and swelling in the knee.
