外侧半月板切除术后X线改变与周围骨密度变化的关系

Relation between X-ray Changes and Changes of Bone Mineral Density around the Knee Joint after Lateral Meniscectomy

目的观察外侧半月板切除术(lateral meniscectomy,LMT)术后膝关节X线改变与周围骨密度(bone mineral density,BMD)变化的关系。方法选择LMT术后128例,膝关节术后X线改变根据Fairbank标准分为0、Ⅰ、Ⅱ、Ⅲ4级,设对应健侧为对照组。应用双能X线骨密度仪分别测量膝关节周围6个感兴趣区(region of interest,ROI)的BMD,并计算出术侧与健侧相对应区域BMD的变化值。结果X线表现为0级时,R1、R2、R3、R4、R5、R6BMD均明显下降,具有显著的统计学意义;X线表现为Ⅰ级和Ⅱ级时,R2、R3、R6BMD,术侧明显低于健侧,具有显著的统计学意义。而R1、R4、R5BMD的变化在统计学上均无明显差别。结论LMT术后X线表现为0级时,膝关节周围BMD均明显下降;X线表现为Ⅰ级和Ⅱ级时,膝关节内侧BMD下降,而外侧BMD变化不明显。

Objective To study the relation between the X - ray changes and the changes of bone mineral density （BMD） around the knee joint after lateral meniscectomy （LMT）. Methods A total of 128 patients who had undergone LMT were selected. They were divided into four groups as 0 grade, Ⅰ grade, Ⅱ grade and m grade according to radiographs after LMT. The healthy contralateral legs served as the control. The BMD of six regions of interest （ ROI ） were measured using dual energy X - ray absorptiometry and the changes of BMD in corresponding ROI between meniscectomized legs and healthy legs were calculated. Results There was a significant difference in the change of BMD in R1, R2, R3, R4, R5 and R6 compared with the control group respectively while X radiographs showed 0 grade after LMT. There was a significant difference in the change of BMD in R2, R3 and R6 compared with the control group respectively while X radiographs showed Ⅰ or Ⅱ grade after LMT. Conclusion The BMD arcund the knee joint decreases apparently as X radiographs show 0 grade after LMT and the BMD in the medial side of the knee joint decreases significantly when X radiographs show Ⅰ or Ⅱ grade after LMT.