多數脊髓損傷患者由於脊髓神經組織遭受到嚴重破壞，使得由大腦發出的運動控制訊息無法順利傳遞，造成活動能力下降而需長時間仰賴輪椅活動，導致臀部壓瘡形成機率大為提高。本研究改良過往所開發之彈簧式動態減壓座墊系統重量過重之缺失，改採剛性較高之塑膠材料製成，並針對脊髓損傷病患進行臀部壓力量測，以評估動態減壓座墊系統對於壓瘡生成預防之效益。
本研究徵召30位脊髓損傷患者(實驗組)與20位健康受測試者(控制組)進行臀部壓力量測，並且比較不同勁度之彈簧(剛體、6.37 N/mm及10.37 N/mm)對於臀部壓力分佈之影響。此外，以自行開發之軟組織力量位移量測儀所獲得之臀部組織材料特性，配合三維動作分析系統取得之板座移動軌跡作為邊界條件，進行臀部有限元素分析及結果驗證，探討乘坐彈簧式動態減壓座墊系統臀部皮膚、脂肪及肌肉組織之所承受之負載。
臀部壓力量測實驗結果顯示，脊髓損傷患者乘坐於低勁度彈簧座墊系統相較於剛體支撐，可降低坐骨結節下方皮膚表層之最大平均壓力13.77 %、壓力峰值28.01 %以及壓力-時間積分值14.58 %。而由有限元素分析之結果可以發現，臀部脂肪與肌肉組織之壓力、剪應力及蒙麥斯應力分佈亦會隨著座墊系統的擺動而產生高低起伏之週期變化。因此，搭配低勁度彈簧之動態減壓座墊系統不僅可以降低臀部坐骨結節下方皮膚表層之壓力與減少壓力負載累積，並且可能改變深層組織之應力分佈，而降低壓瘡之形成之機率。

Patients with paraplegic spinal cord injuries (SCI) need to spend long hours each day sitting on their wheelchair cushions. However, long-term sitting on the wheelchair may raise the probability of pressure sore formation. Many conventional cushion systems are also heavy in weight. As a result, we have developed a rigid plastic dynamic cushion system that is lighter in weight and designed for the purpose of pressure sore prevention. In addition, the efficacy of pressure sore prevention of this cushion system was also evaluated by measuring the buttock pressures in spinal cord injury patients.
Thirty SCI patients (experimental group) and 20 age matched healthy subjects (control group) were recruited to compare the effect of different cushion stiffness (rigid, 6.37 N/mm and 10.37 N/mm) on the buttock pressure distribution. For the finite element analysis of the buttock, the material property was determined by the soft tissue loading-displacement measuring device, and the boundary condition was considered as the sway trajectory of cushion system. The results of finite element analysis were validated and could be used to investigate the loading sustained by the skin, fat and muscle tissues of the buttock.
Results of buttock pressure measurements showed that the reduction of maximum mean pressure, peak pressure and pressure-time integral beneath the ischial tuberosity were 13.77 %, 28.01 % and 14.58 % when sitting on our newly dynamic cushion system of low stiffness as compared to the conventional rigid support seat cushion. Results of finite element analysis showed that the pressure, shear stress and von Mises stress of fat and muscle were altered cyclically by the sway of the dynamic cushion system. So, the dynamic cushion system with low spring stiffness could reduce not only the skin pressure and the cumulative loading beneath ischial tuberosities, but also alter the stress distribution of deep tissues. Therefore, this device may be used to decrease the occurrence of buttock pressure ulcer formation in patients with paraplegic spinal cord injuries.

目錄
摘要 I
ABSTRACT III
致謝 IV
目錄 V
圖索引 X
表索引 XIV
第一章 緒論 1
1-1 前言 1
1-2 文獻回顧 3
1-2-1 臀部壓力量測實驗 3
1-2-2 生物組織與壓力 6
1-2-3 人體臀部之生物力學有限元素分析 7
1-3 文獻總結 11
1-4 研究目的 12
第二章 基礎理論 13
2-1 臀部之解剖學 13
2-2 壓瘡形成方式 18
2-3 輪椅減壓座墊 23
第三章 材料與方法 25
3-1 研究流程 25
3-2 彈簧式動態減壓座墊之設計 27
3-3 臀部壓力量測實驗 29
3-3-1 受測試者 29
3-3-1-1 脊髓損傷患者 29
3-3-1-2 健康受測試者 29
3-3-2 實驗設備與量測方法 30
3-3-3 實驗流程與方法 31
3-3-4 數值分析與統計 33
3-4 臀部有限元素分析 34
3-4-1 有限元素模型建構 34
3-4-2 材料特性 38
3-4-2-1 人體臀部軟組織材料參數量測 38
3-4-2-2 座墊泡綿材料量測 42
3-4-2-3 材料特性之設定 44
3-4-3 邊界條件 46
3-4-3-1 彈簧式動態減壓座墊擺動軌跡量測 46
3-4-3-2 邊界條件之設定 47
第四章 結果 49
4-1 臀部壓力量測實驗結果 49
4-1-1 人體計測參數 50
4-1-1-1 脊髓損傷患者人體計測參數 50
4-1-1-2 健康受測試者人體計測參數 50
4-1-1-3 受測試者人體計測參數間差異性 53
4-1-2 最大平均壓力(Maximum Mean Pressure, MMP) 54
4-1-2-1 脊髓損傷患者左右邊臀部坐骨結節下方之最大平均壓力 54
4-1-2-2 脊髓損傷患者臀部最大平均壓力值受彈簧勁度差異之影響 56
4-1-2-3 健康受測試者左右邊臀部坐骨結節下方之最大平均壓力 57
4-1-2-4 健康受測試者臀部最大平均壓力值受彈簧勁度差異之影響 59
4-1-3 壓力峰值(Pressure Peak) 60
4-1-3-1 脊髓損傷患者左右邊臀部坐骨結節下方之壓力峰值 60
4-1-3-2 脊髓損傷患者臀部壓力峰值受彈簧勁度差異之影響 62
4-1-3-3 健康受測試者左右邊臀部坐骨結節下方之壓力峰值 63
4-1-3-4 健康受測試者臀部壓力峰值受彈簧勁度差異之影響 65
4-1-4 臀部壓力值變化 66
4-1-4-1 脊髓損傷患者臀部壓力值變化 66
4-1-4-2 健康受測試者臀部壓力值變化 68
4-1-5 壓力-時間積分值(Pressure-Time Integrals) 70
4-1-5-1 脊髓損傷患者左右邊臀部坐骨結節下方之壓力-時間積分值 70
4-1-5-2 脊髓損傷患者臀部壓力-時間積分值受彈簧勁度差異之影響 72
4-1-5-3 健康受測試者左右邊臀部坐骨結節下方之壓力-時間積分值 73
4-1-5-4 健康受測試者臀部壓力-時間積分值受彈簧勁度差異之影響 75
4-1-6 壓力中心(Center of Pressure, COP) 軌跡移動最大距離 76
4-1-6-1 脊髓損傷患者之壓力中心軌跡移動最大距離 76
4-1-6-2 健康受測試者之壓力中心軌跡移動最大距離 78
4-2 臀部有限元素分析結果 80
4-2-1 有限元素分析模型收斂測試 80
4-2-2 有限元素分析結果與實驗數值之驗證 82
4-2-3 壓力(Pressure) 84
4-2-3-1 臀部表層皮膚壓力 84
4-2-3-2 臀部深層組織壓力 87
4-2-4 最大剪應力(Maximum Shear Stress) 89
4-2-5 蒙麥斯應力(Von Mises Stress) 91
第五章 討論 93
5-1 臀部壓力量測實驗 93
5-1-1 實驗參數 93
5-1-2 脊髓損傷患者臀部壓力 94
5-1-3 脊髓損傷患者之發病時間差異 96
5-1-4 健康受測試者臀部壓力 98
5-1-5 脊髓損傷患者與健康受測試者臀部臀部壓力差異 100
5-1-6 脊髓損傷患者與健康受測試者臀部壓力中心差異 101
5-2 臀部有限元素分析 103
5-2-1 有限元素分析與臀部壓力量測實驗結果比較 104
5-2-2 臀部軟組織負載情形 106
5-2-3 臀部之生物力學探討 108
5-2-4 彈簧支撐之效益 109
第六章 結論 110
第七章 未來展望 111
參考文獻 112

圖索引
圖 2-1 骨盆 15
圖 2-2 右股骨 16
圖 2-3 下肢肌肉 17
圖 2-4 壓瘡常見的生長部位 18
圖 2-5 壓瘡形成的階段 21
圖 3-1 研究架構流程圖 26
圖 3-2 彈簧式動態減壓座墊實體設計圖 27
圖 3-3 彈簧式動態減壓座墊實體設計展開圖 27
圖 3-4 彈簧式動態減壓座墊擺動示意圖 28
圖 3-5 彈簧式動態減壓座墊實體成品 28
圖 3-6 NOVEL PLIANCE SYSTEM壓力量測設備 30
圖 3-7 氣壓壓力校正器 30
圖 3-8 臀部壓力量測流程 32
圖 3-9 臀部坐骨結節下方左右分區 33
圖 3-10 壓力中心左右與前後方向最大移動距離 33
圖 3-11 臀部MRI影像 35
圖 3-12 右邊臀部模型 35
圖 3-13 臀部坐姿有限元素模型 35
圖 3-14 臀部骨盆-股骨有限元素模型 36
圖 3-15 臀部肌肉層有限元素模型 36
圖 3-16 臀部脂肪層有限元素模型 36
圖 3-17 臀部皮膚層有限元素模型 37
圖 3-18 軟組織力量位移量測儀搭配超音波量測系統 38
圖 3-19 荷重元前端裝置超音波探頭 39
圖 3-20 軟組織應力-應變量測系統 39
圖 3-21 人體臀部軟組織應力-應變曲線圖 40
圖 3-22 豬肉組織 41
圖 3-23 量筒 41
圖 3-24 電子微量天平 41
圖 3-25 INSTRON 8511 型材料試驗機 42
圖 3-26 記憶泡棉標準尺寸 42
圖 3-27 記憶泡綿材料應力-應變曲線 43
圖 3-28 軟組織之平滑線段斜率 44
圖 3-29 泡綿之平滑線段斜率 45
圖 3-30 VICON 460三維動作擷取設備 46
圖 3-31 座墊擺動分析 46
圖 3-32 臀部有限元素動態分析之邊界條件 48
圖 4-1 脊髓損傷患者臀部左右邊最大平均壓力差異 54
圖 4-2 健康受測試者臀部左右邊最大平均壓力差異 57
圖 4-3 脊髓損傷患者臀部左右邊壓力峰值差異 60
圖 4-4 健康受測試者臀部左右邊壓力峰值差異 63
圖 4-5 脊髓損傷患者臀部壓力值變化之差異 66
圖 4-6 健康受測試者臀部壓力值變化之差異 68
圖 4-7 脊髓損傷患者臀部左右邊壓力-時間積分值差異 70
圖 4-8 健康受測試者臀部左右邊壓力-時間積分值差異 73
圖 4-9 脊髓損傷患者左右與前後方向之壓力中心軌跡最大距離 76
圖 4-10 健康受測試者左右與前後方向之壓力中心軌跡最大距離 78
圖 4-11 臀部有限元素模型網格之差異 80
圖 4-12 臀部收斂結果 81
圖 4-13 有限元素分析結果與先前研究臀部壓力量測實驗數值之驗證 82
圖 4-14 有限元素分析結果與本研究臀部壓力量測實驗數值之驗證 83
圖 4-15 臀部皮膚層壓力分佈情形 84
圖 4-16 臀部表層皮膚壓力 86
圖 4-17 臀部之壓力分佈情形 87
圖 4-18 臀部脂肪層壓力 88
圖 4-19 臀部肌肉層壓力 88
圖 4-20 臀部之最大剪應力分佈情形 89
圖 4-21 臀部軟組織之最大剪應力 89
圖 4-22 臀部之蒙麥斯應力分佈情形 89
圖 4-23 臀部軟組織之蒙麥斯應力 89
圖 5-1 脊髓損傷患者與健康受測試者人體計測參數 89
圖 5-2 脊髓損傷患者乘坐3種不同勁度彈簧座墊之臀部壓力差異 89
圖 5-3 脊髓損傷患者發病時間長短之臀部壓力差異 89
圖 5-4 坐姿限制造成壓力中心移動距離之差異 89
圖 5-5 脊髓損傷患者與健康受測試者壓力-時間積分值差異 89
圖 5-6 脊髓損傷患者與健康受測試者臀部壓力中心移動範圍 89
圖 5-7 臀部軟組織負載分佈 89

表索引
表 3-1 臀部模型元素及節點數 37
表 3-2 人體臀部軟組織應力-應變值 40
表 3-3 記憶泡綿材料之應力-應變值 43
表 3-4 臀部軟組織材料參數 45
表 3-5 臀部有限元素動態分析之邊界條件 48
表 4-1 脊髓損傷患者人體計測參數 51
表 4-2 健康受測試者人體計測參數 52
表 4-3 脊髓損傷與健康受測試者的人體計測數 53
表 4-4 人體計測數INDEPENDENT-SAMPLES T TEST 53
表 4-5 脊髓損傷患者之最大平均壓力 55
表 4-6 健康受測試者之最大平均壓力值 58
表 4-7 脊髓損傷患者之壓力峰值 61
表 4-8 健康受測試者之壓力峰值 64
表 4-9 脊髓損傷患者臀部壓力值之變化 67
表 4-10 健康受測試者臀部壓力值之變化 69
表 4-11 脊髓損傷患者之壓力-時間積分值 71
表 4-12 健康受測試者之壓力-時間積分值 74
表 4-13 脊髓損傷患者之壓力中心軌跡移動最大距離 77
表 4-14 健康受測試者之壓力中心軌跡移動最大距離 79
表 4-15 臀部網格細分模型元素及節點數 80
表 4-16 有限元素分析結果與先前研究臀部壓力量測實驗數值 82
表 4-17 有限元素分析結果與本研究臀部壓力量測實驗數值 83
表 4-18 臀部皮膚層壓力 85
表 4-19 臀部脂肪層壓力 88
表 4-20 臀部肌肉層壓力 88
表 4-21 臀部軟組織之最大剪應力 89
表 4-22 臀部軟組織之蒙麥斯應力 89

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