S09.1 ACRYLIC CEMENT SPACER COMBINED WITH FEMORO-TIBIAL NAIL AS SALVAGE THERAPY FOR FAILED TOTAL KNEE REPLACEMENT.

Abstract

Introduction: Failed total knee replacement due to the daemage of bone stock and infection requires removal of prosthesis. Successful arthrodesis is strongly related to the quality of bone stock. Both external fixators and KAFO are not comfortable and thus poor tolerated by elderly patients. Instable knee is very disabling condition. Custom-made femoro-tibial nail combined with acrylic cement spacer offers maintenance of supportive function of extremity after removal of knee prosthesis. Avoidance of leg length discrepance is possible. Nailing can be considered only as salvage procedure for one knee.

Material and Method: Six elderly patients underwent unilateral arthrodesis of the knee after removal of knee prosthesis due to the daemage to the bone stock and periprosthetic infection. They have had conical shape of the lower leg and poor quality to the bone. Thus they were not suitable for conventional knee arthrodesis using external fixator or for pseudoarthrosis and KAFO. After removal of TKR and debridement of periprosthetic tissues an ortograde, custom-made femoro-tibial interlocking nail was inserted. The gap betveen distal femur and proximal tibia was filled with hand-made acrylic cement spacer loaded with vancomycin (2g per 40 g cement) so that the spacer finally gained tubular shape.

Results: No recurrence of infection was noted. Early postoperative full-weight bearing was possible. Implant failure occurred in one case and required replacement of nail and cement spacer. Stress fracture of femoral neck occurred in another case. Despite of this problems all patients has better ADL than with KAFO or after

Conclusion: femoro-tibial nail for failed TKR is good accepted and comfortable for patient. Disadvantage of this type of nail is stiff knee and risk for nail fracture.