The Treatment With Condylar Constrained Prosthesis For Fractures Of The Distal Femur Prosthesis After TKA

Objective:To investigate the feasibility and efficacy of treatment with condylar constrained prosthesis for fractures of the distal femur prosthesis after TKA.Methods:In June2007to October2012period,The distal femoral periprosthetic fractures after TKA were eight cases of patients had taken artificial knee revision surgery treatment with the condylar constrained prosthesis (CCK),3males and5females;aged68to77years,mean age73years.Except one case of fracture caused by the normal activity.causing a fracture after the remaining seven cases were trauma.The clinical manifestations were knee deformity,severe pain,limited mobility.The patients were Kim Ⅲ type,Total8cases8knees.The surgery are used knee median longitudinal incision medial parapatellar approach,renovated prosthesis are used CCK prosthesis,if there were more severe fractures require better combined would use the LISS plate.Results:8knees of8caces were followed from9to68months.an average of31months.There were3cases using CCK joint prosthesis and LISS plate fixation,5cases simply using CCK prosthesis fixation.After review of X-ray all patients were seen no significant loosening of prosthesis,there is no obvious periprosthetic osteolysis either.The patients’knee pain disappeared,the knee activity can be significantly improved, the HSS score from preoperative (4.6±1.4) points,up to the last follow-up (89.5±3.9) points.The preoperative knee score0points, up to the last follow-up (76.3±27.2) points. The range of motion of preoperative knee (23±7) degrees, improve follow-up to last (88±12) degrees.All eight patients were not suffering from a knee infection,osteolysis,dislocation,deep vein thrombosis,decubitus, knee instability and other complications.Conclusion:Although the treatment with condylar constrained prosthesis for fractures of the distal femur prosthesis after TKA is difficult,complicated postoperative complications may occur,or cannot achieve good knee range of motion, through a reasonable surgical plan,a regular postoperative care and the functional exercise can get better result,still need long-term follow-up observation.