What should you know about Japanese bow legs?

With bow legs, the knees stay apart when the feet are together, creating an outward curve through the legs. In young children, alignment changes as the legs grow and develop, so age and growth pattern matter. A curve that affects one leg more than the other, becomes more noticeable, causes pain, or affects walking deserves a clinical review. The clinician may examine gait, leg length, joint movement, and growth, and may request imaging when the pattern is unusual or persistent.

Arrange an assessment if you are concerned about a child’s leg shape, walking pattern, or growth. Bring information about when the curve was first noticed, whether it is changing, and whether close relatives have similar alignment. Do not use braces, supplements, or exercises marketed to straighten the legs without professional guidance. Paediatric physiotherapy may support strength, balance, and movement when those are affected; it does not replace assessment of the bones or growth plates. An orthopaedic team may discuss osteotomy for selected structural deformities after careful evaluation.

Seek prompt medical advice for sudden leg pain, inability to bear weight, swelling after an injury, fever with a painful joint, or a rapidly changing shape. Earlier review is also appropriate when the curve is markedly uneven, walking is deteriorating, the child is losing previously gained abilities, or pain interferes with sleep or play.

Is this alignment expected for the child’s age and growth? Is one side different? Does the examination suggest a bone, joint, or muscle problem? Is imaging needed, and would observation, paediatric physiotherapy, or an orthopaedic procedure be appropriate?