Pes Anserine Bursitis: The Inner-Knee Pain Below the Joint
Tenderness a few inches below the inner knee — common with arthritis, running, and middle age
Updated July 20262 minute read
Pes anserine bursitis is irritation of a small cushioning sac (and the tendons over it) on the inner shin, two to three inches below the knee joint line. It's common in runners, people with knee arthritis, and middle-aged adults, and it almost always settles with activity changes, stretching, and strengthening — not surgery.
What is pes anserine bursitis?
Three tendons from your thigh — the "pes anserine," Latin for goose's foot, after their webbed shape — attach together on the inner shin bone, about two to three inches below the knee joint. A small fluid-filled sac (bursa) cushions them. When that area gets overloaded, the bursa and tendons get irritated, and you feel a tender, achy spot on the inner knee, below the joint itself.
You'll also see this called pes anserine tendinopathy or "anserine syndrome" — in practice the bursa and tendons are irritated together, and the treatment is the same.
Who gets it?
Three groups keep showing up:
- People with knee arthritis — altered walking mechanics overload the inner knee, so the two often coexist.
- Runners, especially after a jump in mileage or hills, and athletes in sports with cutting and side-to-side movement.
- Middle-aged adults, more often women; tight hamstrings, higher body weight, and diabetes each raise the odds.
How do I know it's this and not something else?
Location is the tell. Press around your inner knee:
| Where it's tender | Usual story | More likely |
|---|---|---|
| 2–3 inches below the inner joint line, on the shin | Gradual onset, no injury | Pes anserine bursitis |
| At the inner joint line and above | Collision or twist, then pain | MCL sprain |
| Along the inner joint line | Twisting hurts, clicking or catching | Medial meniscus tear |
Pes anserine pain typically flares climbing stairs, getting up from sitting, and at night when your knees touch. The inner knee pain guide walks the full differential if you're not sure.
What you can try first
- Trim the trigger. Cut the aggravating dose — mileage, hills, deep stair work — by about half for a couple of weeks rather than stopping.
- Ice the spot 15–20 minutes after activity while it's cranky.
- Stretch the hamstrings daily; tightness here directly loads the attachment.
- Strengthen hips and quads — sit-to-stands, bridges, gentle step-ups. Stronger hips take strain off the inner knee.
When it's time to see a physical therapist
If two to three weeks of that hasn't moved the needle, or this keeps coming back every time you ramp up, an evaluation is worth it — a PT can confirm the diagnosis in one visit, sort out the contributing mechanics, and give you a graded plan. Prognosis is genuinely good; surgery is rare.
A hot, swollen knee with fever, a knee that locks, or pain after a real injury is a different conversation — see when to see a PT for knee pain for the red flags and thresholds.
Frequently asked questions
Sources (2)
This article is for education only and isn't medical advice. Always talk to a licensed clinician about your specific situation.