Using a Mathematical Model to Analyze Spinal and Hip Joint Forces of Transfemoral Amputee with Two Different Prosthetic Knees

• Main Authors: Ya-Yun Yang, 楊雅雲
• Other Authors: Chen-Sheng Chen
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/72538682659621147081

碩士 === 國立陽明大學 === 物理治療暨輔助科技學系 === 100 === Due to lose function of the knee joint and related muscles in patients with transfemoral amputees (TFA), knee prosthesis has to replace normal knee functions. However, patients with TFA may place greater loading and increase stance time on the intact limb during gait. Long-term exposure to higher repetitive loading forces leads to pain and degeneration of weight-bearing joints and lower back. This study compared the biomechanics of lower extremity when patient with TFA wear hydraulic-pneumatic (HPKP) and pneumatic knee prosthesis (PKP). To understand whether the new HPKP leads to more symmetrical gait and decreases hip joint force (HJF) on intact limb and lower back force (LBF). Two subjects, including an unimpaired people and a patient with TFA, were recruited in this study. Patient with TFA respectively wore two prosthesis knees for one month acclimatization period. They were asked to attach 31 markers for establishing a mathematical model. The Vicon motion analysis system and force plate were conducted to collect ground reaction force and motion kinematical data. A mathematical software Matlab was implemented to calculate force of hip and L5/S1 joint. After obtaining model validation, hip and L5/S1 joint forces between two limbs were analyzed. Subject with TFA had longer stance time on intact limb than unimpaired subject. Subject with HPKP exhibited slower walking speed than PKP, but subject with PKP had greater HJF in intact limb in the vertical and medio-lateral directions. In the anterior-posterior direction, The LBF of subject with TFA mainly acted in the posterior direction. In the vertical direction, the peak LBF was greater for the PKP and the subject with TFA oscillated more markedly in vertical and medio-lateral direction compared with healthy subject. Therefore, the symmetries of time parameter and HJF between two limbs of subject with TFA were different from normal people. Subject with HPKP had slower speed but also decreased hip and L5/S1 joint forces.