Background： Lateral compartmental osteoarthritis （LCOA）, a major complication after medial mobile-bearing unicompartmental knee arthroplasty （UKA）, is highly associated with the increased stress of the lateral co...Background： Lateral compartmental osteoarthritis （LCOA）, a major complication after medial mobile-bearing unicompartmental knee arthroplasty （UKA）, is highly associated with the increased stress of the lateral compartment. This study aimed to analyze the effects on the stress and load distribution of the lateral compartment induced by lower limb alignment and coronal inclination of the tibial component in UKA through a finite element analysis. Methods： Eight three-dimensional models were constructed based on a validated model for analyzing the biomechanical effects of implantation parameters on the lateral compartment after medial Oxford UKA： postoperative lower limb alignment of 3° valgus, neutral and 3° varus, and the inclination of tibial components placed in 4°, 2° valgus, square, and 2° and 4° varus. The contact stress of femoral and tibial cartilage and load distribution were calculated for all models. Results： In the 3° valgus lower limb alignment model, the contact stress of femoral （3.38 MPa） and tibial （3.50 MPa） cartilage as well as load percentage （45.78%） was highest compared to any other model, and was increased by 36.75%, 47.70%, and 27.63%, respectively when compared to 3° varus. In the condition of a neutral position, the outcome was comparable for the different tibial tray inclination models. The inclination did not greatly affect the lateral compartmental stress and load distribution. Conclusions： This study suggested that slightly varus （undercorrection） lower limb alignment might be a way to prevent LCOAin medial mobile-bearing UKA. However, the inclination （4° varus to 4° valgus） of the tibial component in the coronal plane would not be a risk factor for LCOA in neutral position.展开更多
Background The tibial plateau is asymmetric with a larger medial plateau.We observed from clinical practice that the shape of the tibial plateau does not always present a larger medial plateau.Tibial plateau also show...Background The tibial plateau is asymmetric with a larger medial plateau.We observed from clinical practice that the shape of the tibial plateau does not always present a larger medial plateau.Tibial plateau also showed other shapes.The purpose of this study was to analyze the anthropometric data of the proximal tibia in a large group of Chinese patients undergoing total knee arthroplasty and to investigate the morphology of the resected proximal tibial surface and its gender differences.Methods A total of 822 knees （164 males,658 females） from the Chinese population were measured intraoperatively for medial anteroposterior （MAP） and lateral anteroposterior （LAP） dimensions of the resected proximal tibial surface.The difference of MAP and LAP （DML） was also calculated as MAP minus LAP.We then classified the data into three groups based on the DML （＜-2,-2 to 2,and ＞2 mm） to analyze the morphology of the proximal tibia and its distribution between male and female.Results The shape of proximal tibial plateau was of three types：larger medial plateau type,symmetric type,and larger lateral plateau type.There were significant differences between males and females in relation to the shape distribution of the proximal tibial plateau （P ＜0.05）.Most of the proximal tibial plateau was asymmetric,with 517 of 822 （62.9％） tibia having a DML ＞2 mm and 120 of 822 （14.6％） tibia having a DML＜-2 mm.Only 185 of 822 （22.5％） tibia had a DML between-2 and 2 mm.Conclusion The results of this study can be used as a guideline to design tibial components with different DMLs to better match the different anthropometry of the resected tibial surface.展开更多
目的 探讨以髌韧带附着处及胫骨截骨面中心点为参考标志构建的改良型Akagi线作为胫骨假体旋转对位参考轴的准确性。方法 2021年7月—12月,选择72例因膝关节骨关节炎伴内翻畸形行三维CT扫描的患者。其中男18例,女54例;年龄47~84岁,平均6...目的 探讨以髌韧带附着处及胫骨截骨面中心点为参考标志构建的改良型Akagi线作为胫骨假体旋转对位参考轴的准确性。方法 2021年7月—12月,选择72例因膝关节骨关节炎伴内翻畸形行三维CT扫描的患者。其中男18例,女54例;年龄47~84岁,平均64.9岁。术前髋-膝-踝角0°~26°,平均9.3°。将CT图像导入交互式医学影像控制系统Mimics 21.0,建立膝关节数字化三维模型。在股骨三维模型中标记出内上髁凹和外上髁最高点的位置,构建外科通髁轴及其投影的垂线[胫骨前后(anteroposterior,AP)轴)]。在胫骨三维模型中,以髌韧带附着处作为解剖参考标志构建胫骨假体旋转对位参考轴,包括髌韧带附着处内侧缘(C)和后交叉韧带止点中点(O)的连线(Akagi线)、胫骨截骨面中点(GC)和C点的连线[(髌韧带内侧轴(medial border axis of the patellar tendon,MBPT)]、髌韧带附着处内侧1/6处和GC点的连线[髌韧带内侧1/6轴(medial sixth axis of the patellar tendon,MSPT)]、髌韧带附着处内侧1/3处和O点的连线[髌韧带内侧1/3轴1(medial third axis of the patellar tendon 1,MTPT1)]和髌韧带附着处内侧1/3处和GC点的连线[髌韧带内侧1/3轴2(medial third axis of the patellar tendon 2,MTPT2)]。测量5种参考轴与AP轴之间的夹角,并统计其与AP轴夹角分布情况(分为≤3°、3°~5°、5°~10°和>10°)。结果 Akagi线和MBPT分别相对于AP轴内旋(1.6±5.9)°和(2.4±6.9)°,而MSPT、MTPT1和MTPT2则相对于AP轴分别外旋(5.4±6.6)°、(7.0±5.8)°和(11.9±6.6)°。各参考轴与AP轴夹角及其分布情况差异均有统计学意义(F=68.937,P<0.001;χ^(2)=248.144,P<0.001)。其中Akagi线与MBPT间比较差异无统计学意义(P=0.067),与MSPT、MTPT1和MTPT2比较差异均有统计学意义(P<0.012 5)。结论 当人工全膝关节置换术中无法准确辨清后交叉韧带止点位置时,可以参考胫骨截骨面中点使用MBPT作为改良型Akagi线,以构建可靠的胫骨假体旋转对位。展开更多
基金This study was supported by grants from the National Natural Science Foundation of China(No.81673776)the capital health research and development of special,China(No.2016-2-4062).
文摘Background： Lateral compartmental osteoarthritis （LCOA）, a major complication after medial mobile-bearing unicompartmental knee arthroplasty （UKA）, is highly associated with the increased stress of the lateral compartment. This study aimed to analyze the effects on the stress and load distribution of the lateral compartment induced by lower limb alignment and coronal inclination of the tibial component in UKA through a finite element analysis. Methods： Eight three-dimensional models were constructed based on a validated model for analyzing the biomechanical effects of implantation parameters on the lateral compartment after medial Oxford UKA： postoperative lower limb alignment of 3° valgus, neutral and 3° varus, and the inclination of tibial components placed in 4°, 2° valgus, square, and 2° and 4° varus. The contact stress of femoral and tibial cartilage and load distribution were calculated for all models. Results： In the 3° valgus lower limb alignment model, the contact stress of femoral （3.38 MPa） and tibial （3.50 MPa） cartilage as well as load percentage （45.78%） was highest compared to any other model, and was increased by 36.75%, 47.70%, and 27.63%, respectively when compared to 3° varus. In the condition of a neutral position, the outcome was comparable for the different tibial tray inclination models. The inclination did not greatly affect the lateral compartmental stress and load distribution. Conclusions： This study suggested that slightly varus （undercorrection） lower limb alignment might be a way to prevent LCOAin medial mobile-bearing UKA. However, the inclination （4° varus to 4° valgus） of the tibial component in the coronal plane would not be a risk factor for LCOA in neutral position.
基金This study was supported by funds from the Sino-Germany Cooperation Project of Ministry of Science and Technology of China （No. 2011DFA31340）, the Beijing Science and Technology Planning Projects of Beijing Science and Technology Committee （No. Z131100005213004）, and the Instrument Research Project of the National Natural Science Foundation of China （No. 81327001）.
文摘Background The tibial plateau is asymmetric with a larger medial plateau.We observed from clinical practice that the shape of the tibial plateau does not always present a larger medial plateau.Tibial plateau also showed other shapes.The purpose of this study was to analyze the anthropometric data of the proximal tibia in a large group of Chinese patients undergoing total knee arthroplasty and to investigate the morphology of the resected proximal tibial surface and its gender differences.Methods A total of 822 knees （164 males,658 females） from the Chinese population were measured intraoperatively for medial anteroposterior （MAP） and lateral anteroposterior （LAP） dimensions of the resected proximal tibial surface.The difference of MAP and LAP （DML） was also calculated as MAP minus LAP.We then classified the data into three groups based on the DML （＜-2,-2 to 2,and ＞2 mm） to analyze the morphology of the proximal tibia and its distribution between male and female.Results The shape of proximal tibial plateau was of three types：larger medial plateau type,symmetric type,and larger lateral plateau type.There were significant differences between males and females in relation to the shape distribution of the proximal tibial plateau （P ＜0.05）.Most of the proximal tibial plateau was asymmetric,with 517 of 822 （62.9％） tibia having a DML ＞2 mm and 120 of 822 （14.6％） tibia having a DML＜-2 mm.Only 185 of 822 （22.5％） tibia had a DML between-2 and 2 mm.Conclusion The results of this study can be used as a guideline to design tibial components with different DMLs to better match the different anthropometry of the resected tibial surface.
文摘目的 探讨以髌韧带附着处及胫骨截骨面中心点为参考标志构建的改良型Akagi线作为胫骨假体旋转对位参考轴的准确性。方法 2021年7月—12月,选择72例因膝关节骨关节炎伴内翻畸形行三维CT扫描的患者。其中男18例,女54例;年龄47~84岁,平均64.9岁。术前髋-膝-踝角0°~26°,平均9.3°。将CT图像导入交互式医学影像控制系统Mimics 21.0,建立膝关节数字化三维模型。在股骨三维模型中标记出内上髁凹和外上髁最高点的位置,构建外科通髁轴及其投影的垂线[胫骨前后(anteroposterior,AP)轴)]。在胫骨三维模型中,以髌韧带附着处作为解剖参考标志构建胫骨假体旋转对位参考轴,包括髌韧带附着处内侧缘(C)和后交叉韧带止点中点(O)的连线(Akagi线)、胫骨截骨面中点(GC)和C点的连线[(髌韧带内侧轴(medial border axis of the patellar tendon,MBPT)]、髌韧带附着处内侧1/6处和GC点的连线[髌韧带内侧1/6轴(medial sixth axis of the patellar tendon,MSPT)]、髌韧带附着处内侧1/3处和O点的连线[髌韧带内侧1/3轴1(medial third axis of the patellar tendon 1,MTPT1)]和髌韧带附着处内侧1/3处和GC点的连线[髌韧带内侧1/3轴2(medial third axis of the patellar tendon 2,MTPT2)]。测量5种参考轴与AP轴之间的夹角,并统计其与AP轴夹角分布情况(分为≤3°、3°~5°、5°~10°和>10°)。结果 Akagi线和MBPT分别相对于AP轴内旋(1.6±5.9)°和(2.4±6.9)°,而MSPT、MTPT1和MTPT2则相对于AP轴分别外旋(5.4±6.6)°、(7.0±5.8)°和(11.9±6.6)°。各参考轴与AP轴夹角及其分布情况差异均有统计学意义(F=68.937,P<0.001;χ^(2)=248.144,P<0.001)。其中Akagi线与MBPT间比较差异无统计学意义(P=0.067),与MSPT、MTPT1和MTPT2比较差异均有统计学意义(P<0.012 5)。结论 当人工全膝关节置换术中无法准确辨清后交叉韧带止点位置时,可以参考胫骨截骨面中点使用MBPT作为改良型Akagi线,以构建可靠的胫骨假体旋转对位。
