The Runner Who Wants to Know Which Joint Is Guilty
Priya, 28, is a recreational runner logging 40 km a week and is eight weeks out from a half marathon. For three weeks she has had lateral left knee pain that starts around 6 km, reaches 3/10, and settles within an hour of stopping. There is no swelling, locking, giving way, or night pain; stairs are fine going up but ache going down. Single-leg squat on the left: the knee drifts medial to the second toe, the foot pronates, the trunk leans left, and the right side of the pelvis drops. On the right the pattern is markedly cleaner. Weight-bearing ankle dorsiflexion in the knee-to-wall test is 9° on the left and 15° on the right. Side-lying hip abduction is 4/5 on the left with early fatigue and 5/5 on the right. Single-leg heel raise: 20 left, 24 right. She asks whether she should stop running and whether the problem is her knee, her hip, or her ankle.
1. Which additional screens would you run before committing to a plan, and how would you interpret them?
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What you already have. A frontal-plane collapse on the left (medial knee drift, pronation, contralateral pelvic drop) with an asymmetrical ankle and a weak left hip abductor. That is a movement pattern, not a diagnosis, and it is not yet clear which restriction is driving it.
Add:
- Knee-to-wall with the heel flat and the knee tracking over the second toe, both sides. Confirm the 9° vs 15° finding and note whether the left end-feel is bony or soft. A bony block changes the plan entirely (no amount of calf stretching will add range).
- Single-leg squat with a heel lift on the left. If the knee drift and trunk lean clean up, the ankle restriction is contributing to the proximal pattern. This is a quick, high-value test.
- Single-leg bridge and side plank hold time, plus hip external rotation strength - abduction alone does not capture the whole frontal-plane picture.
- Ober/Thomas test to see whether hip flexor or TFL/IT band tightness limits hip extension, which changes pelvic position during stance.
- Navicular drop or foot posture to quantify the pronation you saw.
- Training load: weekly volume progression over the last six weeks, shoe age, surface, and downhill volume.
Interpretation logic. If the heel lift cleans up the squat, the ankle is a driver and treat it first. If the knee still collapses with a lifted heel, the hip is the primary target. If both persist, address both, but sequence them; the single-leg squat is your outcome measure, not the number of exercises you prescribe.
2. Given the findings, what would you prioritize in the first four weeks, and how would you manage her running load?
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Prioritize ankle dorsiflexion and left hip abductor capacity, in that order, while keeping her running.
Why the ankle first: a 6° side-to-side difference in a runner is meaningful, and a restricted ankle changes where the tibia and knee go during loading. Restoring it is usually fast (2–4 weeks) and makes the hip work easier to express.
Ankle (daily, 10 minutes):
- Calf and soleus self-release, 60–90 s per side.
- Knee-to-wall mobilization with a band and active ankle dorsiflexion, 3 x 10, holding 2 s at end range.
- Soleus stretch with the knee bent, 30 s x 3.
Hip (three times a week):
- Side-lying hip abduction, 3 x 12, slow, no trunk rotation.
- Single-leg bridge, 3 x 8 with a 3-second hold.
- Sidestep with band, 3 x 10 per direction.
- Integrate: single-leg squat to a bench with a heel lift, then without; step-down with knee tracking over the second toe, 3 x 8.
Running load. Do not stop running entirely; her pain is 3/10, settles within an hour, and there are no irritability red flags. Cut weekly volume by roughly 20–30% for two weeks, remove downhills and cambered roads, and keep intensity easy. Use a simple rule: pain during a run must stay at or below 3/10 and be back to baseline within 24 hours. If it is not, reduce volume another 20% before adding any new corrective work.
Re-test the knee-to-wall, single-leg squat, and pain-free running distance at week 2 and week 4.
3. What would make you refer Priya rather than continue, and how would you answer her question about whether it is her knee, hip, or ankle?
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Refer if:
- Pain rises above 5/10, persists at rest, or wakes her at night.
- New swelling, locking, catching, or a sense of giving way appear - lateral knee pain that starts to feel unstable is no longer a simple load problem.
- Pain localizes to the joint line with a mechanical block, or there is a clear effusion.
- No meaningful change in symptoms or in the single-leg squat after 4 weeks of consistent work, or symptoms spread above or below the knee.
Answering her question honestly. She is asking for one guilty joint, and the useful answer is that all three are involved, but not equally. Her ankle is the most restricted and the most likely to be driving the pattern; her left hip abductors are the weakest link in the frontal plane; her knee is where the load shows up. The knee is the victim, not the cause, but the knee is also what we monitor because it tells us whether the plan is working.
Use the heel-lift test as a live demonstration: let her feel the squat improve when the ankle range is borrowed. That gives her a reason to do the ankle work, which is the least interesting part of the program.
Be clear about scope. You are not diagnosing iliotibial band syndrome or patellofemoral pain; you are correcting modifiable movement restrictions and referring if the presentation stops behaving like a load-and-movement problem.