Knee arthrodesis with simultaneous lengthening using the Ilizarov method.

OBJECTIVE To determine whether knee arthrodesis with simultaneous lengthening using the Ilizarov method for a nonreconstructable knee joint with bone loss and infection is a successful salvage procedure. DESIGN Retrospective review of patients. SETTING University hospital-based orthopaedic practice. PATIENTS From 1999 to 2001, 4 consecutive patients with a nonreconstructable knee joint, bone loss, and infection after trauma underwent knee arthrodesis with simultaneous lengthening. INTERVENTION Arthrodesis of the knee with simultaneous limb lengthening through an osteotomy of the tibia and/or femur and the use of an Ilizarov frame. External bone stimulation was used at the knee arthrodesis site and the lengthening sites. Application of this device began during the early distraction phase and continued until frame removal. MAIN OUTCOME MEASURES Bony union at the arthrodesis and bone lengthening sites, alignment of the lower extremity, limb length discrepancy, infection, pain, and outcome scales (SF-36 scores and American Academy of Orthopaedic Surgeons lower limb modules). RESULTS Bony union of the knee arthrodesis and lengthening sites and good alignment were achieved in all 4 patients. Mean amount of lengthening was 5.4 cm (range 2.5-11.5 cm). Average time in frame was 11 months (range 6-17 months). Limb length discrepancy after treatment averaged 1.8 cm (range 0.6-3.7 cm). Mean duration of follow-up after frame removal was 35 months (range 28-48 months). At follow-up, infection had not recurred, pain was not present, and assistive devices were not needed for ambulation. Average SF-36 scores improved in all 8 categories, and the average American Academy of Orthopaedic Surgeons lower limb modules improved from a mean of 33 (range 11-37) to a mean of 68 (range 51-76). CONCLUSION Knee arthrodesis with simultaneous lengthening can be performed successfully using the Ilizarov method. It enables surgeons to optimize limb length during knee arthrodesis. The use of external fixation and the avoidance of internal implants may be advantageous in the presence of or history of infection. The Ilizarov frame provides stability that allows weight bearing during treatment.