Ko Dong Oh, Lee Song, Kim Kyung Tae, Lee Jae Il, Kim Jin Woo, Yi Seong Min
Department of Orthopedic Surgery, Seoul Sacred Heart General Hospital, Seoul, Korea.
Knee Surg Relat Res. 2017 Jun 1;29(2):115-121. doi: 10.5792/ksrr.16.013.
To analyze the thickness of cement mantle at the bone cement interface in knees with closed and open box designs in total knee arthroplasty (TKA).
Eighty cases of TKA were performed from October 2013 to March 2014. The average age of the patients was 68.4 years. All patients were women and they were divided into two groups: group I with a closed box implant (PS150 RP, n=40) and group II with an open box implant (LPS-Flex, n=40). We measured the cement mantle thickness at the bone cement interface from the distal femur and proximal tibia. If the thickness was >1 mm, it was considered an outlier.
The mean cement mantle thickness at the interface was 1.4 mm in the distal femur and 0.8 mm in the proximal tibia. The value exceed 1 mm in 40 cases (50%) in the distal femur and in 6 cases (7.5%) in the proximal tibia (p<0.001). The mean cement mantle thickness measured in the distal femur was 1.7 mm in group I and 1.0 mm in group II. The value exceed 1 mm in 32 cases (80%) in group I and in 8 cases (20%) in group II (p<0.000).
The cement mantle at the interface was thicker in the knees with the closed box implant than those with the open box implant in TKA, especially in the distal femoral area. A thick cement mantle at the interface should be avoided because it affects the gap balance. In case of using a closed box implant in TKA, cementing should be performed with extra care.
分析全膝关节置换术（TKA）中采用封闭盒式和开放盒式设计的膝关节骨水泥界面处骨水泥套的厚度。
2013年10月至2014年3月共进行了80例TKA手术。患者平均年龄为68.4岁。所有患者均为女性，分为两组：I组采用封闭盒式植入物（PS150 RP，n = 40），II组采用开放盒式植入物（LPS - Flex，n = 40）。我们测量了股骨远端和胫骨近端骨水泥界面处的骨水泥套厚度。如果厚度>1mm，则视为异常值。
股骨远端界面处骨水泥套的平均厚度为1.4mm，胫骨近端为0.8mm。股骨远端有40例（50%）的值超过1mm，胫骨近端有6例（7.5%）（p<0.001）。I组股骨远端测得的骨水泥套平均厚度为1.7mm，II组为1.0mm。I组有32例（80%）的值超过1mm，II组有8例（20%）（p<0.000）。
TKA中采用封闭盒式植入物的膝关节界面处的骨水泥套比采用开放盒式植入物的更厚，尤其是在股骨远端区域。应避免界面处骨水泥套过厚，因为这会影响间隙平衡。在TKA中使用封闭盒式植入物时，骨水泥固定应格外小心。
