Why Does My Knee Hurt Going Down Stairs?

Going down is somehow worse than going up. That's usually how people describe it — a dull ache or sharp twinge right around or under the kneecap, showing up on stairs, sometimes on hills, sometimes when you least expect it. It's one of the most common knee complaints out there, and it has a name most people have never heard: patellofemoral pain.

The good news is that this pattern is well understood, and it responds well to the right kind of movement — not necessarily the rest you might assume it needs.

Can I keep reading, or do I need urgent care?

Most knee pain on stairs is safe to manage yourself. Get urgent medical attention instead if you have any of these:

• A visibly deformed knee, or inability to bear any weight after an injury
• Sudden, severe swelling immediately after a twisting injury
• A hot, red, significantly swollen knee with fever
• Your knee giving way repeatedly, or locking and being unable to straighten

If none of these apply, keep reading.

The Short Answer

Pain around or behind the kneecap that's worse on stairs — especially going down — is a hallmark pattern of what's called patellofemoral pain. A comprehensive clinical practice guideline on this exact condition specifically names stair descent, squatting, and prolonged sitting as classic activities that reproduce this type of pain, since all three load the kneecap against the thigh bone while the knee is bent.¹

This isn't usually a sign of cartilage damage or something structurally serious. It's more often related to how the kneecap tracks in its groove and how well the surrounding muscles, especially around the hip and thigh, are managing the load placed on the knee.

A Little Anatomy

Your kneecap (patella) sits in a groove at the front of your thigh bone and glides up and down as you bend and straighten your knee. Going down stairs is particularly demanding on this joint because your quadriceps muscles have to control your body weight while lengthening — a type of contraction that places more force through the kneecap than going upstairs does. When the muscles supporting the knee and hip aren't managing that load as efficiently as they could, the tissue around and behind the kneecap can become sensitive, producing the ache many people feel specifically on descent.

Common Causes of Knee Pain on Stairs

1. Patellofemoral pain. The most common cause of this specific pattern, related to how load is managed at the kneecap during bent-knee activities like stairs and squatting.

2. Reduced hip and thigh muscle strength. Weakness in the muscles around the hip and front of the thigh is a commonly identified contributor, since these muscles help control how the knee and kneecap track during stair activities.

3. A recent increase in activity. A sudden jump in running, stair climbing, hiking, or similar activities can outpace what your knee is currently conditioned for.

4. Other joint-related causes. Less commonly, cartilage wear, ligament issues, or other structural conditions can also cause stair-related knee pain, which is part of why persistent or unusual patterns are worth assessing.

5. Unrelated causes. Occasionally, knee discomfort reflects general deconditioning or an unrelated strain rather than a specific stairs-related pattern.

Is This Normal, or Something to Watch?

Generally reassuring:

• Ache or discomfort specifically with stairs, squatting, or prolonged sitting
• No significant swelling, locking, or giving way
• Pain that fluctuates with activity rather than steadily worsening

Worth a closer look:

• Noticeable swelling, warmth, or a knee that's hot to the touch
• The knee locking, catching, or giving way repeatedly
• Pain that's persistently unchanging regardless of activity or rest
• Progressively worsening pain rather than pain that fluctuates

What You Can Do About It

• Modify, don't eliminate, stair use. Taking stairs more slowly, using a railing, or leading with the less affected leg can reduce strain while you build capacity, rather than avoiding stairs altogether.
• Build hip and thigh strength progressively. Exercise, particularly strengthening around the hip and knee, is a core recommendation in current clinical guidelines for this type of knee pain.¹
• Avoid sudden jumps in activity. Gradually increasing stair climbing, running, or hiking tends to be better tolerated than a sudden big increase.
• Be patient with the timeline. This type of knee pain often improves gradually over weeks with consistent exercise rather than resolving quickly.

Gentle Exercises to Try

Stop any exercise that causes sharp pain, swelling, or a sense of instability in the knee.

1. Sit-to-Stand — Why it helps: builds the same muscle control needed for stair descent, in a lower-demand movement.
Sitting in a sturdy chair, stand up slowly using both legs evenly, then lower back down with control. 8–10 reps, once daily. A mild burning sensation in the thigh muscles is expected; sharp knee pain is not.

2. Step-Downs — Why it helps: directly builds the controlled lowering strength used going down stairs.
Standing on a low step, slowly lower one foot toward the ground and tap it lightly, then return to standing. 8–10 reps each side, once daily, using a low step height you can control comfortably. Stop if it causes sharp pain.

3. Side-Lying Hip Abduction — Why it helps: strengthens hip muscles that help control knee alignment during stair activities.
Lying on your side, lift your top leg upward while keeping it straight, then lower slowly. 10–12 reps each side, a few times a week. Stop if it increases knee pain.

4. Wall Sit — Why it helps: builds general quadriceps endurance without the repetitive impact of stairs.
Back against a wall, slide down to a comfortable bent-knee position and hold. Start with 15–20 seconds, building up gradually, once daily. Stop if you feel sharp pain rather than muscular fatigue.

Common Mistakes and Misconceptions

• "This means my cartilage is wearing away." Most stair-related knee pain isn't primarily a cartilage problem — it's more often related to how load is managed around the kneecap, which responds well to targeted strengthening.
• "I should avoid stairs completely until it's gone." Complete avoidance can lead to deconditioning; modifying how you use stairs while building strength is usually more effective than avoiding them entirely.
• "I just need better knee alignment or orthotics." These may help some people as part of a broader plan, but exercise-based strengthening has the strongest supporting evidence as a first-line approach.¹
• "An MRI will tell me exactly what's wrong." Imaging isn't usually needed for this pattern unless there are signs pointing to another cause, since patellofemoral pain is typically diagnosed from your symptoms and a physical exam.

When Should You See a Doctor or Physiotherapist?

Seek an assessment if you notice:

• Noticeable swelling, warmth, or a knee that's hot to the touch
• The knee locking, catching, or giving way repeatedly
• Pain that's persistently unchanging regardless of activity or rest
• Any of the urgent symptoms listed near the top of this article
• Progressively worsening pain rather than pain that fluctuates with activity
• No improvement after several weeks of self-management

Frequently Asked Questions

Why does going down stairs hurt more than going up?
Descending places more force through the kneecap because your thigh muscles are working to control your body weight while lengthening, which is more demanding on this particular joint than climbing.

Do I have runner's knee?
"Runner's knee" is a common nickname for this same pattern (patellofemoral pain), though it affects plenty of people who don't run at all — it's about how load is managed at the knee, not a specific sport.

Should I stop exercising if my knee hurts on stairs?
Not necessarily — modifying the specific movements that hurt while continuing other activity, and adding targeted strengthening, tends to work better than stopping activity altogether.

Will this go away on its own?
It can improve with time and activity modification, but structured strengthening exercise generally speeds up and improves the reliability of recovery compared with waiting it out.

Do I need an X-ray or MRI for knee pain on stairs?
Usually not for a typical pattern like this — imaging is more useful when symptoms don't fit the usual picture, aren't improving, or there's a specific concern like swelling or locking.

Key Takeaways

Knee pain on stairs, especially going down, is a common pattern often related to how the kneecap tracks and how well the hip and thigh muscles are managing load — not usually a sign of structural damage. Modifying stair use, building hip and thigh strength progressively, and avoiding sudden jumps in activity are reasonable, evidence-informed places to start. Swelling, locking, giving way, or pain that isn't improving after several weeks is worth a professional assessment.

This article is for general educational purposes only and does not replace individualized medical or physiotherapy assessment. If you have persistent, worsening, or concerning symptoms, please consult a qualified healthcare professional.

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References

1. Willy RW, Hoglund LT, Barton CJ, et al. Patellofemoral Pain. J Orthop Sports Phys Ther. 2019;49(9):CPG1–CPG95. doi:10.2519/jospt.2019.0302

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Ayesha Shoaib, DPT, is a Doctor of Physical Therapy with clinical experience across orthopedics, neurology, pediatrics, women's health, and intensive care. She writes evidence-informed content at The Motion Kind to help readers understand what's happening in their bodies and when it's worth seeing a professional.