Knee arthrodesis by the Ilizarov method in the treatment of total knee arthroplasty failure.

BACKGROUND: Currently, the main indication for knee arthrodesis is septic failure of a total knee arthroplasty (TKA). The purpose of this study was to evaluate the results of knee arthrodesis by circular external fixation performed in the treatment of TKA failure in which revision arthroplasty was not indicated.

METHODS: The study involved 19 patients who underwent knee arthrodesis by the Ilizarov method. Clinical and functional assessments were performed, including Knee Society Score (KSS). A postoperative clinical and radiographic evaluation was conducted every three months until the end of the treatment. Postoperative complications and eventual leg shortening were recorded.

RESULTS: KSS results showed a significant improvement with respect to the preoperative condition. Of the 16 patients in the final follow-up, 15 patients (93.7%) achieved complete bone fusion. Major complications occurred in patients treated for septic failure of TKA and most occurred in patients over 75years of age; the mean final leg shortening was four centimeters.

CONCLUSION: In our experience, the Ilizarov method is effective for performing a knee arthrodesis in the case of extensive bone loss. At the same time, it is possible to correct the associated leg deformities or limb length difference. In addition, only the Ilizarov method provides a mechanical stimulus for bone formation and improves the quality of the bone and of the microcirculation, which enhances the host response against infection. Despite these attributes, knee arthrodesis by the Ilizarov method must be considered a 'salvage procedure' in cases of severe outcomes from knee surgery in which revision arthroplasty is not indicated.