Tibial Component Revision Arthroplasty Using Porous Tantalum Cone for Symptomatic Progressive Periprosthetic Proximal Tibial Ganglion Cyst about All-Polyethylene Tibia Primary Total Knee Replacement: A Case Report and Review of Literature

Introduction: Intraosseous ganglion cysts are an uncommon variant found in the subchondral bone. We report here the development of an intraosseous ganglion cyst of the proximal tibia in the setting of a prior left total knee arthroplasty (TKA) with an all-polyethylene tibial component. Case Report: The cyst was diagnosed on routine follow-up radiographs approximately 4 years status post-TKA. Although initially asymptomatic, 1 year later the patient presented with progressive knee pain and ambulation limitations, so revision TKA was indicated. Computed tomography confirmed an osteolytic lesion suggestive of a penetrating ganglion. Given the absence of malrotation or malalignment of the well-fixed femoral component, the decision was made to proceed with the revision of the stemmed tibial component cemented through a porous tantalum cone. Postoperatively, the patient had complete resolution of pain and instability with 0–120° of stable range of motion, which has persisted to the latest follow-up at over 6 months post-operative, with radiographic resolution of the cyst. Conclusion: This case demonstrates a ganglion cyst surrounding total knee implants as a possible source of persistent pain following TKA. To our knowledge, this is the first report of such a case. This case demonstrates that refractory painful knee implants secondary to tibial ganglion cysts can be treated successfully with revision arthroplasty. Keywords: Knee revision arthroplasty, ganglion cyst, porous cone, outcomes.