Successful two-stage revision of a KineSpring® joint unloading implant: a case study

Few nonsurgical treatment options are available to the patient with debilitating knee osteoarthritis (OA) that is refractory to conservative care. The KineSpring® System joint unloading implant is a unique device that reduces the load carried by the medial compartment of the knee joint by up to 13 kilograms during the stance phase of gait. We report a case of a male patient who underwent implant with the KineSpring System for symptomatic knee OA but subsequently required revision due to local infection. We performed a novel two-stage revision procedure where the absorber unit was removed in the first phase and a new absorber was placed 3 months later after the infection resolved. A key finding of this case was that knee OA pain resolved with the KineSpring System, returned following explant of the absorber unit, and resolved again following implant of the new absorber. Another important aspect of this case was that the femoral and tibial bases of the KineSpring System remained in situ, which simplified each phase of the revision procedure.