Effect of foot deformity on conventional mechanical axis deviation and ground mechanical axis deviation during single leg stance and two leg stance in genu varum

This study assessed the effect of foot deformity on the loading axis of lower limbs in 33 patients with genu varum caused by varying etiologies. Deviation at the knee from the hip ankle line (conventional) and hip foot line (centre of hip to centre of heel) was calculated.  Mechanical axis deviation varied with the talocalcaneal angle and single leg stance. Patients with a fixed subtalar varus and with severe genu varum, where the normal compensatory subtalar eversion could not compensate showed that conventional mechanical axis deviation and ground mechanical axis deviation degrees was significantly higher in single leg stance when compared to two leg stance. The authors conclude that foot deformity should be included during preoperative evaluation and planning for knee deformity correction.