Weale A E, Murray D W, Baines J, Newman J H
Nuffield Orthopaedic Centre, Headington, Oxford, UK.
J Bone Joint Surg Br. 2000 Sep;82(7):996-1000. doi: 10.1302/0301-620x.82b7.10466.
Failure of a unicompartmental knee replacement (UKR) may be caused by progressive osteoarthritis of the knee and/or failure of the prosthesis. Limb alignment can influence both of these factors. We have examined the fate of the other compartments and measured changes in leg alignment after UKR. A total of 50 UKRs was carried out on 45 carefully selected patients between 1989 and 1992. At operation, deliberate attempts were made to avoid overcorrection of the deformity. Four patients died, one patient was lost to follow-up and two knees were revised before review which was at a minimum of five years. Standard long-leg weight-bearing anteroposterior views of the knee and skyline views of the patellofemoral joint were taken before and at eight months and five years after operation. The radiographs of the remaining 43 knees were reviewed twice by blind and randomised assessment to measure the progression of osteoarthritis within the joints. Overcorrection of the deformity in the coronal plane was avoided in all but two knees. Only one showed evidence of progression of osteoarthritis within the patellofemoral joint, and this was only identified in one of the four assessments. Deterioration in the state of the opposite tibiofemoral compartment was not seen. Varus deformity tended to recur. Recurrent varus of 2 degrees was observed between eight months and five years after operation. There was no correlation between the postoperative tibiofemoral angle and the extent of recurrent varus recorded at five years. Changes in alignment may be indicative of minor polyethylene wear or of subsidence of the tibial component. The incidence of progressive osteoarthritis within the knee was very low after UKR. Patients should be carefully selected and overcorrection of the deformity be avoided.
单髁膝关节置换术（UKR）失败可能是由膝关节进行性骨关节炎和/或假体失败引起的。肢体对线可影响这两个因素。我们研究了其他关节间室的转归，并测量了UKR术后下肢对线的变化。1989年至1992年间，对45例精心挑选的患者共进行了50例UKR手术。手术时，刻意避免过度矫正畸形。4例患者死亡，1例患者失访，2例膝关节在至少5年的复查前进行了翻修。在术前、术后8个月和5年拍摄膝关节标准长腿负重前后位片以及髌股关节天际线位片。对其余43例膝关节的X线片进行两次盲法随机评估，以测量关节内骨关节炎的进展情况。除2例膝关节外，所有膝关节均避免在冠状面过度矫正畸形。只有1例显示髌股关节内有骨关节炎进展的证据，且仅在四次评估中的一次发现。未观察到对侧胫股关节间室状态恶化。内翻畸形有复发倾向。术后8个月至5年观察到2°的复发性内翻。术后胫股角与5年时记录的复发性内翻程度之间无相关性。对线的变化可能表明聚乙烯磨损轻微或胫骨组件下沉。UKR术后膝关节内进行性骨关节炎的发生率非常低。应仔细挑选患者，并避免过度矫正畸形。
