CAJ | 학술논문

目的探讨组配式人工半骨盆假体重建后骨盆生物力学改变及假体力学结构特点.方法 (1)建立正常骨盆的三维有限元模型和离体试验骨盆模型.于骨盆表面选取8个特征测点,在相同的载荷及边界条件下,利用有限元模型计算测点表面应力(σFEM),通过离体试验测量测点应变值,并计算标本表面应力(σEXP).对σFEM和σEXP进行线性回归分析验证.(2)利用验证的正常骨盆有限元模型进行左侧骨盆缺损(Ⅱ+Ⅲ区)及人工假体重建模型的建模.计算重建骨盆健侧特征测点的表面应力(σRS)及患侧髂骨截骨处内、外侧皮质表面应力(σRR),分别与正常骨盆相同位置测点应力值(σNS,σNR)进行比较.(3)分析假体应力传导结构表面应力分布特点及应力集中部位.结果 (1)骨盆有限元计算结果与离体试验结果有良好的一致性(R~2=0.87),模型仿真度较高.(2)重建后健侧特征测点σRS与正常骨盆σNS近似(t=1.81,P=0.08).患侧髂骨截骨处内侧皮质σRR与σNR差异无统计学意义(t=0.47,P=0.65),外侧皮质σRR明显高于σNR(t=2.78,P=0.02).(3)假体应力传导结构主要由后侧传导.应力集中部位位于下排钉孔周围、髂骨固定座与侧面固定翼片连接处、人工髋臼与髂骨固定连接处,系统应力峰值(183 MPa)位于人工髋臼与髂骨固定座连接部位.结论组配式人工半骨盆假体重建符合骨盆生物力学特点,较好地恢复了应力传导.
목적 탐토조배식인공반골분가체중건후골분생물역학개변급가체역학결구특점.방법 (1)건립정상골분적삼유유한원모형화리체시험골분모형.우골분표면선취8개특정측점,재상동적재하급변계조건하,이용유한원모형계산측점표면응력(σFEM),통과리체시험측량측점응변치,병계산표본표면응력(σEXP).대σFEM화σEXP진행선성회귀분석험증.(2)이용험증적정상골분유한원모형진행좌측골분결손(Ⅱ+Ⅲ구)급인공가체중건모형적건모.계산중건골분건측특정측점적표면응력(σRS)급환측가골절골처내、외측피질표면응력(σRR),분별여정상골분상동위치측점응력치(σNS,σNR)진행비교.(3)분석가체응력전도결구표면응력분포특점급응력집중부위.결과 (1)골분유한원계산결과 여리체시험결과 유량호적일치성(R~2=0.87),모형방진도교고.(2)중건후건측특정측점σRS여정상골분σNS근사(t=1.81,P=0.08).환측가골절골처내측피질σRR여σNR차이무통계학의의(t=0.47,P=0.65),외측피질σRR명현고우σNR(t=2.78,P=0.02).(3)가체응력전도결구주요유후측전도.응력집중부위위우하배정공주위、가골고정좌여측면고정익편련접처、인공관구여가골고정련접처,계통응력봉치(183 MPa)위우인공관구여가골고정좌련접부위.결론 조배식인공반골분가체중건부합골분생물역학특점,교호지회복료응력전도.
Objective To analysis the biomechanical characteristics of the reconstructed pelvis with modular hemi-pelvie prosthesis by finite element (FE) method. Methods A subject-specific finite element model of pelvis was established. Th experiment was performed on the same cadaveric pelvis. Eight points on the surface of cortical bone was determined. Both the same load and boundary conditions were applied on the FE model and experiment. The stress by experiment (σ EXP) was calculated based on the data collected from the strain discs. Linear regression was performed with the stress predicted by FE model (σFEM) and experi-ment data to validate the FE model. A defect pelvic (with zone Ⅱ +Ⅲ in left hemi-pelvis) FE model was con-structed and assembled with the prosthesis. The stress distribution on the eontra lateral hemi-pelvis was cal-culated by the reconstructed pelvic FE model (σRS), and the results were compared with that of the normal pelvis (σNS). Also the comparison was clone at the resection level of the affected hemi-pelvis between normal pelvic FE model (σNR) and reconstructed model (σRR) both on medial and lateral cortical bone of the pelvis. Structural analysis was performed on the whole set of implant. Results FE predictions were strongly correlated with experimental results (R~2=0.87). No significant difference was found between the σRS and σNS (t=1.81, P=0.08). Regarding to the stress distribution at lilac resection level, no difference was found between σNR and σRR on the medial side (t=0.47, P=0.65). However, on the lateral side, σRR were signifi-cantly higher than the σNR (t=2.78, P=0.02). The peak stress of the prosthesis was about 183 MPa located at the conjunction of the acetabulum and the iliac fixation part. The main load conduction path on the prosthe-sis was at the posterior side of column portion part of the iliac fixation. Conclusion Reconstruction with modular hemi-pelvic prosthesis could recover the pelvic biomechanics with rational mechanical design.