Runner's Knee: Symptoms, Causes & How Physical Therapy Helps
Pain around the kneecap that flares with stairs, squats, and running
Updated July 20262 minute read
Runner's knee (patellofemoral pain) is an irritation around the kneecap caused by how the knee is loaded — not structural damage. Physical therapy resolves most cases in 6–12 weeks with targeted strengthening and load management, without imaging, injections, or surgery.
What is runner's knee?
Runner's knee — patellofemoral pain syndrome, if you want the formal name — is pain around or behind the kneecap. Despite the name, you don't have to be a runner: it shows up in hikers, lifters, desk workers who take up a new sport, and teenagers going through growth spurts.
The kneecap glides in a groove at the end of your thigh bone every time your knee bends. When the load on that joint outpaces what it's ready for, the tissue gets irritated. It is a load problem, not a damage problem — which is exactly why it responds so well to the right rehab.
Symptoms: how to know if you have it
- Aching around or behind the kneecap, hard to point to with one finger
- Pain going down stairs, squatting, or after sitting with bent knees
- Occasional grinding or clicking (common and not dangerous)
- Little or no swelling — significant swelling suggests something else
Pain in one pinpoint spot below the kneecap is more likely jumper's knee, and sharp pain on the outside of the knee during runs points to IT band syndrome — the stairs-and-squats guide maps the patterns side by side.
What causes it
The usual pattern is a change in load: more miles, more stairs, a new sport, heavier squats — before the hips and quads were ready to absorb it. Hip and quad strength, training volume, and movement habits all contribute. Footwear and "kneecap tracking" matter less than most articles claim.
How physical therapy treats runner's knee
This is where PT has its strongest evidence. Treatment typically includes progressive strengthening of the quads and hips, short-term load management so the joint calms down while you stay active, and a graded return to full training. Most plans involve one or two visits a week with focused home exercises between them.
How long does recovery take?
Most people feel meaningful improvement in about six weeks and return to full activity by twelve. Pain that's been around longer than a year can take more patience — but the trajectory is the same.
When to see someone
If pain has lasted more than two or three weeks, changes how you move, or keeps returning when you ramp up activity, an evaluation is worth it. A PT can usually confirm runner's knee in one visit and give you a plan the same day — the full thresholds (including the red flags that need a doctor first) are in when to see a PT for knee pain, and what PT costs covers the money side.
Frequently asked questions
Mild cases sometimes settle with a short break from aggravating activity. But because the underlying cause is usually how the knee is loaded — hip and quad strength, training volume, mechanics — pain often returns when you ramp back up. Addressing the cause is what makes the fix stick.
Sources (5)
- Willy RW, et al. Patellofemoral Pain: Clinical Practice Guidelines. J Orthop Sports Phys Ther. 2019. — JOSPT
- van der Heijden RA, et al. Exercise for treating patellofemoral pain syndrome. Cochrane Database Syst Rev. 2015. — Cochrane
- Willy RW, et al. Patellofemoral Pain. J Orthop Sports Phys Ther. 2019. — JOSPT
- Crossley KM, et al. 2016 Patellofemoral pain consensus statement from the 4th International Patellofemoral Pain Research Retreat, Manchester. Part 2: recommended physical interventions (exercise, taping, bracing, foot orthoses and combined interventions). Br J Sports Med. 2016. — BJSM
- AAOS OrthoInfo. Patellofemoral pain syndrome. — OrthoInfo
This article is for education only and isn't medical advice. Always talk to a licensed clinician about your specific situation.