Absent Knee Extensor Mechanism, Fixed Flexion Deformity, Leg Length Inequality and Foot Deformity in an 11 Year Old Girl Treated with Knee Disarticulation

This is a case of absent knee extensor mechansim, servere flextion deformity of the knee, leg length inequality and foot deformity in an 11 year old girl. Reconstructive surgery using the llizarov technique was attempted at the age of 2.5 years and was initially successful. Unopposed hamstring activity lead to deformity recurrence following frame removal. Three treatment options were then considered: supracondylar femoral ostetomy with hamstring transfer, knee fusion and knee disarticulation. The first two options would have required multiple limb lengthening’s together with reconstruction of the foot. The aims of treatment were to achieve normal weight-bearing, legs of equal length and a normal gait. It was decided that an amputation was the best way to achieve this. This girl now walks well and is a kneen cyclist.