Diagnostic test for knock knees and bow legs
Physiologic valgus
Our leading paediatric consultants can diagnose and treat knock knees and bow legs
About physiologic valgus
Knock knees (physiologic valgus) is when a child's knee joints point inwards and touch each other. Bow legs (Blount's disease) is just the opposite — when the legs curve outwards, instead of standing straight.
While most children grow out these conditions, symptoms could also be a sign of rickets or osteoperosis. When testing for bow legs and knock knees, your consultant will examine your child's legs and carry out a physical examination.
While most children grow out these conditions, symptoms could also be a sign of rickets or osteoperosis. When testing for bow legs and knock knees, your consultant will examine your child's legs and carry out a physical examination.
Need to know
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How do you test for bowlegs or knock knees? icon plus
The most effective way to test for bow legs is a visible assessment. When a child stands with straight legs and toes pointed forward, the consultant will see if your knees are too far apart. Your consultant will also ask your child to walk up and down to see how rotated the knees are. If just one of the legs is bowed, they may order an X-ray of the lower legs to rule out bone deformities.
With knock knees, a visible assessment is also carried out. Your consultant will assess whether your child's feet and ankles are further apart than usual. They'll also compare the angle of the lower leg and the upper leg. -
How to prepare icon plus
No preparation is needed. Your consultant will explain the procedure and answer any questions you may have. -
After the assessment icon plus
If your child has knock knees or bow legs, they are likely to grow out of it. If your consultant thinks there may be an underlying health condition such as rickets, they may order more tests.
If the problems persist, your consultant may recommend surgery. This could involve inserting guided growth implants, which help straighten and realign your child's leg as they grow. In severe cases, your child may need an osteotomy. Here, a wedge of bone is removed and the leg is realigned with metal implants. Both these procedures can be used to align knock knees too.
Our knee consultants
We're proud to work with leading knee experts, whose skills are matched by their integrity and compassion. They are experienced in paediatric care and have a team of paediatric nurses and physiotherapists to support each child during investigations and treatment.




Our locations
From complex orthopaedic surgery to tests and procedures for adult and childhood conditions, we provide exceptional care across our network of hospitals, outpatient centres and specialist clinics.
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The Wellington Hospital Elstree Waterfront
The Waterfront Business Park
Beaufort House, Elstree Road
Elstree WD6 3BS
Request an orthopaedic appointment for your child
We're happy to help you make an appointment with one of our experienced paediatric consultants who specialise in orthopaedics. We can also make imaging and outpatient physiotherapy appointments for you.
Call us today
020 7079 4344
This content is intended for general information only and does not replace the need for personal advice from a qualified health professional.