Development of a knee joint ligament rupture simulator based on mechanical loads and geometric conditions

2018 Fiscal Year Final Research Report

• Project/Area Number: 17K14554
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Materials/Mechanics of materials
• Research Institution: Hokkaido University
• Principal Investigator: Takeda Ryo 北海道大学, 工学研究院, 助教 (90645095)
• Project Period (FY): 2017-04-01 – 2019-03-31
• Keywords: 膝関節 / 靭帯 / 損傷 / 変位負荷 / サイクル負荷 / 有限要素モデル

Outline of Final Research Achievements

The knee ligament rupture mechanism based on the mechanical load condition and the geometry was analyzed. First, a knee joint ligament experimetal setup consisting of a universal material testing machine, a knee joint fixation jig, and a thermo‐hygrostat chamber was created. Porcine stifle joint was used as a substitute knee joint. The knee model was set in the knee joint fixation jig, and the load was measured via a force sensor located between the material testing mechine and the joint fixation jig.The material testing machine applied a cyclic displacement to the knee model until the ligament was damaged.Then the mechanical property values,such as the load,required for ligament damage was determined. Furthermore, the ligament geometry was extracted from MRI by an image segmentation process. Based on the obtained mechanical properties and geometry of the ligaments, a finite element analysis model capable of reproducing knee joint ligament loads was constructed.

Free Research Field

機械工学

Academic Significance and Societal Importance of the Research Achievements

本研究を通して次の成果を得た．一定の変位負荷の影響よりも1度の過剰な変位負荷が靭帯損傷に及ぼす影響が大きい．また，膝関節の姿勢により弛緩状態及び緊張状態の靭帯が存在するため，靭帯損傷の割合が異なる．さらに，既に断裂している靭帯が存在する場合，他の靭帯が損傷しやすくなる．これらの測定結果を基に膝関節靭帯断裂を再現するシミュレーションの構築した結果，本解析シミュレーションモデルを使用して正確に膝靭帯の支持力が推定可能となった．したがって，本研究全体を通して靭帯断裂メカニズムを定量的に推定可能となり，靭帯再建術の手術法の評価に応用されることが今後期待される．