使用可活动衬垫TACK表面膝关节假体置换的初步临床报告

目的基础与临床研究已证实,聚乙烯磨损导致的骨溶解仍然是膝关节置换术后晚期失败的主要原因;TACK为第三代可活动衬垫的膝关节假体,其聚乙烯关节面为非限制性解剖形旋转面,它存在于一个金属的胫骨平台假体的轨道内,可在轨道内进行内外旋转并与股骨内外髁面高度匹配,运动中能始终保持最大的面接触,理论上可大大地减少磨损和假体松动。报告使用可活动衬垫TACK假体进行膝关节置换的初步临床结果。方法自1997年11月～2001年3月,采用可活动衬垫TACK(totalar ticu latingcement lessknee) 膝关节假体对61例88侧病变膝关节进行了表面膝关节置换术,31例患者(45膝)获得了1年以上的随访,平均随访25.4个月。采用HSS评分及X线检查对临床效果进行评价。结果经手术治疗,优良率为96.4%,HSS评分平均为86.4分;膝关节可以完全伸直,下肢力线明显好转,外翻角为0°～10°,平均5.7°;膝关节活动范围从术前0°-6.5°-68.3°,改善到术后0°-2°-88.4°。经X线检查证实未发现有骨溶解、假体松动或活动衬垫脱位等并发症。结论作为第三代可活动衬垫的表面膝关节置换的短期临床效果令人满意,假体的设计增加了股骨与聚乙烯衬垫之间的匹配,减少了接触应力和聚乙烯的磨损。其长期效果还需要进一步观察。

Preliminary clinical outcome of mobile-bearing knee replacement

Objective Experimental and clinical data suggest that fixed element knee designs a re not able to both supply adequate mobility and eliminate unnecessary constra int forces,as well as provide low contact stresses compatible with pr olonged life of UHMWPE bearing components.The present study investi-gated the preliminary clinical outc ome of TACK(Total Articulating Cementless Knee)system,a new design of mobile-bearing knee prosthesis.Methods Eighty-eight knees in 61patients underwent total knee replace-ment by using TACK were reviewed.Forty-five knees of 31patients were followed-up at least one year.The HSS knee rating score system as well a s X-ray films were used to evaluate th e clinical results with the mean follow-up period of 25.4months.Results At the latest follow-up examination,the rate of good to excellent clinical results was 96.4%.The range of motion was improved from 0-6.5-68.3degrees preoperatively to0-2-88.4degrees at the latest follo w-up.The complications such as oste olysis around the prosthesis,prosthetic loosening and dislocation of meniscus bearings were not found.Conclusion The TACK Knee is a third generation knee system design ed to introduce movable bearings between the metal tibial and femoral components that would reduce the sur face and subsurface stress states at the bearing surfaces and at the bone-implant interfaces by maximiz ing the conformity of the tibial and f emoral components and allowing mo-bility of the bearing surface.In an a verage of more than two years experie nce,it was observed that there was no aseptic loosening of the componen ts.A long term follow-up is obviously necessary to make more precise statement about this knee replaceme nt system.