膝关节屈伸运动形态的有限元分析

摘要

BACKGROUND:Three dimensional finite element analysis is widely used in orthopedics, but research in the knee flexion movement is not much. OBJECTIVE:To analyze biomechanical properties of knee flexion using finite element analysis.METHODS:Three dimensional finite element models and models of knee flexion at 30 degrees, 60 degrees and 120 degrees were established. Femoral forward movement, femur inward movement, tibia internal rotation and tibia vara were analyzed at different flexion angles. RESULTS AND CONCLUSION:(1) When knee flexion was at 30 degrees, 60 degrees and 120 degrees, the femur had backward movement. The backward movement value was larger at 60 degrees than at 30 and 120 degrees (P<0.05). The backward movement value was larger at 120 degrees than at 30 degrees (P>0.05). (2) The femur had outward movement at 30 degrees, and inward movement at 120 degrees. The inward movement value was significantly larger at 120 degrees than at 30 and 60 degrees (P<0.05). No significant difference in outward movement was determined between the 30 and 60 degrees (P>0.05). (3) Tibia internal rotation was not significantly different at 30, 60 and 120 degrees of flexion (P>0.05). (4) Tibia vara was found at 30, 60 and 120 degrees of flexion, but the tibia vara was not obvious at 120 degrees. The tibia vara was maximum at 60 degrees, and significantly higher than that at 120 degrees (P<0.05). The tibia vara was larger at 30 degrees than at 120 degrees (P>0.05). (5) These findings verify that backward movement was most obvious at 60 degrees. Femur inward movement was most large at 120 degrees. Tibia internal rotation was noticeable at 30 and 120 degrees. Tibia vara was remarkable at 60 degrees.%背景：三维有限元分析在骨科中被广泛应用，在膝关节屈曲运动中的研究不多。目的：对膝关节屈曲运动的生物力学特性进行三维有限元分析。　　方法：建立膝关节的三维有限元模型以及膝关节屈曲30°，60°以及120°时的三维有限元模型，分析膝关节不同屈曲位股骨前移情况、股骨内移情况、胫骨内旋情况和胫骨内翻情况。　　结果与结论：①股骨前移：在膝关节屈曲30°，60°和120°时股骨均出现后移，膝关节屈曲60°时的股骨后移值大于屈曲30°和屈曲120°(P<0.05)；膝关节屈曲120°股骨后移值大于屈曲30°，但差异无显著性意义(P>0.05)；②股骨内移：在膝关节屈曲30°时股骨外移，在膝关节屈曲120°时膝关节内移，膝关节屈曲120°时股骨内移值明显大于屈曲30°和屈曲60°时(P<0.05)；膝关节屈曲30°和屈曲60°时外移值比较差异无显著性意义(P>0.05)；③胫骨内旋：在膝关节屈曲30°，60°和120°时胫骨均出现内旋，3者比较差异均无显著性意义(P>0.05)；④胫骨内翻：在膝关节屈曲30°，60°和120°时胫骨均出现内翻，其中屈曲120°时胫骨内翻不明显，膝关节屈曲60°时胫骨内翻度数最大，明显高于屈曲120°时(P<0.05)；膝关节屈曲30°时胫骨内翻度数大于屈曲120°时，但差异无显著性意义(P>0.05)；⑤结果表明，膝关节在屈曲60°时股骨后移最明显，膝关节屈曲120°时股骨内移值最大，膝关节屈曲30°和屈曲120°时胫骨内旋明显，膝关节屈曲60°时胫骨明显内翻。