膝关节单髁置换术后胫骨假体周围及对侧关节间室骨密度变化的研究

Study on bone densities of tibial periprosthesis and contralateral interarticular compartment after unicompartment knee arthroplasty

目的 研究膝关节单髁置换术后胫骨假体周围及对侧关节间室的骨密度改变情况,为膝关节单髁关节置换术的临床应用及并发症的预防提供数据参考.方法 采用前瞻性研究的方法.选取38例累及内侧关节间室的膝关节骨性关节炎患者,均行膝关节单髁置换术治疗.于术前及术后1周、3个月、6个月和12个月分别测定患侧肢体下肢力线.于术后1周、3个月、6个月和12个月分别测定胫骨假体周围骨密度和对侧胫骨干骺端骨密度.结果 所有患者均手术顺利,随访期间无患者出现假体松动、假体下沉以及因各种原因导致的翻修事件.术后1周及术后3、6和12个月患侧肢体下肢力线与术前比较差异无统计学意义（P〉0.01）.术后3、6和12个月胫骨假体周围骨密度明显低于术后1周[（1.07 ± 0.05）、（1.00 ± 0.04）、（0.99 ± 0.05）g/cm2比（1.15 ± 0.04）g/cm2],而且术后6和12个月明显低于术后3个月,差异均有统计学意义（P〈0.01）;术后6个月与术后12个月比较差异无统计学意义（P〉0.01）.术后3、6和12个月对侧关节间室骨密度与术后1周比较差异无统计学意义（P〉0.01）.结论 在不追求矫正患侧肢体下肢力线的情况下,膝关节单髁置换术后1年胫骨假体周围骨密度呈下降趋势,而对侧关节间室骨密度无明显改变.

Objective To study the postoperative bone densities of tibial periprosthesis and contralateral interarticular compartment, in order to provide references and data for clinical application and complication prevention of unicompartment knee arthroplasty（UKA）. Methods The study adopted a prospective study method.Thirty-eight patients with knee osteoarthritis involving medial interarticular compartment were selected, and all patients were treated with UKA. The alignment of operated limb before operation and 1 week,3 months,6 months and 12 months after operation was measured.The bone densities of tibial periprosthesis and contralateral tibial metaphysis 1 week,3 months,6 months and 12 months after operation were measured. Results All patients underwent successful surgery. No patient had loosening of prosthesis, sinking of prosthesis and revision events caused by various causes during follow-up.There was no statistical difference in alignment of operated limb 1 week,3 months,6 months and 12 months after operation compared with that before operation（P〉0.01）.The bone densities of tibial periprosthesis 3, 6 and 12 months after operation were significantly lower than those 1 week after operation： （1.07 ± 0.05）, （1.00 ± 0.04） and （0.99 ± 0.05） g/cm2vs. （1.15 ± 0.04） g/cm2, furthermore the bone densities 6 and 12 months after operation were significantly lower than those 3 months after operation,and there were statistical differences（P〈0.01）;but there was no statistical difference between 6 months after operation and 12 months after operation（P〉0.01）.There was no statistical difference in contralateral tibial metaphysis 3, 6 and 12 months after operation compared with that 1 week after operation（P〉0.01）.Conclusions Without fully alignment of operated limb correction,the bone density of tibial periprosthesis 1 year after UKA declines, but the bone density of contralateral interarticular compartment does not change significantly.