Amelioration in Ankle Pain and Improvement in Function After Total Knee Arthroplasty for Ipsilateral Knee and Ankle Osteoarthritis: A Report of Two Cases

We report 2 cases of ipsilateral ankle and knee osteoarthritis (OA), with the chief complaint being chronic ankle and knee pain. In the first patient, the ankle pain was more severe than the knee pain, whereas the second patient had more severe pain in the knee than in the ankle. In both cases, varus malalignment of the knee and varus tilt of the ankle joint were detected on standing radiographs. The severity of OA was found to be grade 4 in the knee, according to the Kellgren–Lawrence grading system, and stage IIIa in the ankle, according to the modified Takakura ankle OA classification system. Navigation-assisted total knee arthroplasty was performed in both cases, leading to a decreased degree of varus malalignment in the knee and ankle, as well as a significantly improved patient-based outcome in both joints. Correction of malalignment of the ankle by total knee arthroplasty relieved the severe pain and restored optimal function in the ankle without surgical intervention.