Knees Knock When Running: What It Can Mean

As you land and push off, the thigh, hip, knee, ankle, and foot work as a chain. The knee may drift inward when the hip muscles do not control the thigh well, when the foot rolls inward, or when fatigue changes your running form. Some people have a natural alignment called knock knees, also known as genu valgum. The appearance alone does not show how much strain a joint is experiencing.

Pain around the kneecap, swelling, catching, giving way, or a clear difference between the legs gives a clinician more useful information than a brief video impression. A physiotherapist can watch walking, squatting, and running, then check strength, flexibility, balance, and footwear.

Reduce the running load that brings on symptoms and choose lower-impact activity while the knee settles. Avoid suddenly adding hills, speed work, or long distances. A gradual return should be guided by comfortable walking, controlled single-leg movement, and the absence of increasing swelling.

A tailored programme may include hip and thigh strengthening, balance drills, mobility work, and technique changes. Do not force the knees outward or copy exercises from another runner if they increase pain. Children and adolescents may need age-appropriate assessment; [Paediatric Physiotherapy](/treatments/physiotherapy-and-rehabilitation/paediatric-physiotherapy/) can address movement during growth.

Arrange an assessment for pain that keeps returning, swelling after runs, repeated buckling, locking, reduced motion, or symptoms that interfere with stairs or daily activities. Seek urgent care after a major twist or impact if the knee looks deformed, cannot bear weight, becomes rapidly swollen, or is hot with fever.

Ask: Is the inward movement coming mainly from my hip, knee, ankle, or foot? Which running changes are safe now? Do I need imaging? How should I progress strengthening, and what symptoms mean I should stop? If bone alignment is a major factor, ask whether [Osteotomy](/treatments/reconstructive-orthopedic-surgery/osteotomy/) is relevant or not.