Chapter 60: Bowed Legs and Knock Knees in a Child

Description of the Symptom

Bowed legs and knock knees describe the position of a child's knees in relation to one another in the frontal plane. The condition may be either unilateral or bilateral.

Bowed legs, or genu varum, are defined as excessive space between the femoral condyles (known as the intercondylar distance) when the medial malleoli are in contact, the knees extended, and the tibiofemoral axis is aligned on the frontal plane.¹ Genu varum may be associated with excessive medial hip rotation, foot pronation and knee hyperextension.

Knock knees, or genu valgum, are defined as excessive space between the medial malleoli (known as the intermalleolar distance) when the medial femoral condyles are in contact, knees extended, and the tibiofemoral axis is aligned on the frontal plane.^1,2 Genu valgum may be associated with excessive lateral hip rotation, foot supination, and knee hyperextension. This chapter describes possible causes of bowed legs and knock knees in a child.

Special Concerns

• Post-traumatic changes in lower extremity alignment or a painful limp

• Progressive limp leading to refusal to walk with or without pain

• Grossly asymmetric presentation of lower extremity alignment

• History of multiple fractures