What might cause knee pain when going up and down stairs?

Knee pain when climbing or descending stairs is most often caused by patellofemoral pain syndrome ("runner's knee") or knee osteoarthritis. Both conditions affect how the kneecap tracks and how the joint absorbs pressure, which is why stairs — an activity that loads the knee with several times your body weight — tend to trigger discomfort.

Other possible causes include meniscus tears, patellar tendinitis, cartilage wear, or ligament strain. Symptoms may include a dull ache, sharp pain behind the kneecap, stiffness, swelling, or a grinding sensation.

Because stair-related knee pain can stem from many overlapping conditions, identifying the likely cause early can help you avoid unnecessary worry and choose the right next step — whether that's rest, physical therapy, or seeing a doctor. A free, instant, online symptom check can help you narrow down possible causes in just a few minutes based on your specific symptoms, age, and health history. It's a fast, private way to get clarity before deciding whether home care is enough or if it's time to consult a professional.

Reviewed for medical accuracy: 07/14/2026