Reconstruction of Complete Knee Extensor Mechanism Loss with Gastrocnemius Flaps

We assessed the outcome after reconstruction of traumatic, complete, infected, extensor mechanism loss attributable to high-velocity open knee injuries in eight consecutive patients (all males) who presented to us between February 2005 and September 2007 at an average followup of 24 months. All were treated with gastrocnemius flaps. The loss in extensor mechanism was the patellar tendon in five patients, patella and patellar tendon in two patients, and combined patella, quadriceps, and patellar tendon in one patient. The size of the defect ranged from 8 × 5 cm to 15 × 15 cm. The patients were evaluated for functional outcome of the knee, resolution of infection, range of flexion of the knee, and return to work. Four patients had an excellent outcome whereas the others had a good outcome using the Hospital for Special Surgery knee rating scale. All flaps healed primarily with resolution of infection. The average knee flexion was 110°. All patients except two returned to their original occupation. Three patients had an extensor lag of 5°. The gastrocnemius flap is a good option for open knee injuries with extensor mechanism loss, giving consistent results across a wide spectrum of presentation.