Outcomes of knee arthrodesis following infected total knee arthroplasty: a retrospective analysis of 8 cases

Background There is insufficient information regarding patient-based outcomes after knee arthrodesis following infected total knee arthroplasty (TKA). The purpose of this study was to analyze outcomes in patients who underwent knee arthrodesis following infected TKA using clinical and radiographic measurements including a patient-based outcome measuring system. Methods We evaluated 8 patients (mean age 72.9 years) who were followed for more than 3 years after arthrodesis. Clinical and radiographic evaluation was performed, including examination of the patient’s function and use of supportive equipment for walking. The Japanese knee osteoarthritis measurement (JKOM) was used for measuring patient-based outcomes and health-related quality of life. Result Knee fusion was achieved in 7 patients. The mean limb-length discrepancy was 5.4 cm. All patients could walk at least inside the house, and activity of daily living (ADL) independence was achieved by the patients with successful knee fusion, although walking aids, including a shoe lift causing little discomfort, were required. The results of JKOM for the patients with successful fusion were comparable to the data for patients who underwent TKA. Conclusions When knee arthrodesis was performed for infected TKA cases, pain was reduced and ADL independence was established when knee fusion was achieved. This study demonstrated that information from subjective and functional evaluations of knee arthrodesis patients is useful in understanding postoperative activity and situations, and revealed the importance of supportive elements for walking.