Knock knees in teens: what to know

Knock knees in teens should be assessed by growth pattern, symptoms, and leg alignment rather than appearance alone. Mild alignment can be part of normal development, while a change that persists, worsens, or causes discomfort deserves an examination.

Knock knees, also called genu valgum, describe knees that angle inward when the legs are straight. A clinician may look at walking, standing alignment, hip and foot position, joint movement, and the gap between the ankles. The assessment may distinguish a flexible movement pattern from a fixed bony alignment. One side being noticeably different from the other can be useful information.

Some teenagers have no pain or activity limitation. Others notice aching around the knees, tired legs, altered running mechanics, or difficulty with particular activities. Alignment can also be influenced by growth, previous injury, joint conditions, or how the feet and hips control movement.

Arrange a musculoskeletal assessment if the appearance is changing or symptoms interfere with sport, stairs, walking, or daily tasks. Bring a brief description of when symptoms began and whether they affect one or both legs. A clinician may recommend observation, targeted exercises, activity adjustments, or imaging when the examination suggests a structural concern.

A physiotherapist can work on strength, balance, hip and knee control, and movement habits when these contribute to symptoms. See [Paediatric Physiotherapy](/treatments/physiotherapy-and-rehabilitation/paediatric-physiotherapy/) for an overview of child and adolescent rehabilitation. Do not use braces, insoles, or internet exercises without checking that they suit the teenager’s findings.

Book a timely appointment for persistent pain, limping, reduced activity, swelling, stiffness, repeated falls, or alignment that is clearly worsening. Seek prompt medical advice after a significant injury, or if the leg becomes suddenly difficult to use. Urgency is guided by these symptoms and changes, not by the label knock knees itself.

Ask whether the alignment is within the expected growth pattern, whether both legs are affected similarly, and what examination findings matter most. You can also ask whether an X-ray is needed, which activities are reasonable, how progress will be monitored, and whether a referral to Paediatric Physiotherapy or an orthopaedic specialist would add value.