Glossary
Varus knee (bow legs)
Quick answer
A varus knee is one where the leg bows outward, so the knees sit further apart than the ankles when standing. This alignment puts extra load through the inner side of the knee and is common with medial osteoarthritis, explains Doha knee surgeon Dr. Pablo Gelber, who assesses leg alignment at Aman Hospital.
What it means
Varus, also written genu varum, describes the angle of the leg. A line drawn from the hip to the ankle normally passes close to the centre of the knee. In a varus leg that line passes towards the inner side.
Mild bowing is normal in toddlers and often straightens with growth. In adults it can be the way someone is built, or it can develop as the inner cartilage and meniscus wear away.
Why it matters
The more varus the leg, the more weight goes through the inner compartment. Over years this can wear the cartilage on that side and cause pain on the inner knee, which in turn increases the bowing.
Alignment also matters in ligament and cartilage surgery. A cartilage repair or meniscus transplant on the inner side may fail if the leg stays strongly varus, and some ACL revision cases are affected by it too.
How it is assessed and treated
Dr. Gelber looks at you standing and walking and may request a full-length standing X-ray of both legs to measure the angle. Strengthening, weight management and unloading braces or insoles can ease symptoms. For an active person with inner-knee arthritis and a varus leg, a high tibial osteotomy can shift load to the healthier outer side.
Frequently asked questions
Can bow legs be straightened in adults?
Yes, an osteotomy can correct alignment by cutting and realigning the bone. Whether it is advisable depends on symptoms, age, activity and the state of the joint.
Are bow legs always a problem?
No. Many people with mild varus never have trouble. It becomes relevant when there is inner-knee pain or wear, or when planning knee surgery.
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