Hyperextended knees are referred to as which deformity?

• A. Genu Recurvatum
• B. Genu Varum
• C. Genu Valgum
• D. Genu Flexum

Answer: (A)

Hyperextension of the knee beyond straight alignment is called genu recurvatum. In this deformity the knee extends past zero degrees, so the leg lengthens a bit as the joint sits in an extended position rather than resting at neutral. Picture the knee reaching past full extension during standing or gait, with the joint line effectively going into extra extension. This is different from genu flexum, where the knee cannot fully straighten and stays flexed. It’s also not the same as genu varum, which is bow-legged alignment with the knees apart, or genu valgum, which is knocked knees with the knees closer together. Genu recurvatum can arise from ligamentous laxity or certain injuries or neuromuscular conditions, so recognizing it helps guide further assessment of knee stability and alignment.