應用田口法於單髁人工膝關節置換術參數選擇之研究

The study of the influence of parameter selections on unicompartmental knee arthroplasty using a Taguchi method

何治穎(Chih-Ying Ho)

指導教授 ： 黎文龍 ； 劉建緯

國立臺北科技大學/機電學院/製造科技研究所/碩士(2010年)

https://doi.org/10.6841/NTUT.2010.00058

摘要

觀察單髁人工膝關節置換術的歷史趨勢中，可發現隨著手術技術與觀念的不斷精進下，其成功率與存活率已有相當之提昇，但在臨床上仍可得知手術失敗的現象出現，此情形代表要使得單髁人工膝關節置換術有更佳的結果產生，必然須針對手術失敗之因素來做更進一步之追蹤與研究探討。另外在觀察眾多研究單髁人工膝關節置換術的報告中發現，大都是針對手術影響因素進行各別探討，卻較少有綜合各項影響因子作一統整規劃之研究出現，故如何整合此些影響參數來給予醫師做一多方面之手術建議，並找出對手術最具顯著影響之因子，相信會讓單髁人工膝關節置換術更加成熟與穩重。
　　本研究以不同幾何形狀與材質組合之聚乙烯脛骨元件，進行各種膝關節的對位分析，並應用田口實驗計劃法來模擬醫師針對膝內翻7.5°，並且脛骨後傾7.5°之患者進行手術時的情況，來探討脛骨植入物元件類別、膝內翻矯正角度與脛骨後傾角等因子水準數的混合搭配，並設定誤差因子，再以產生於脛骨元件上之最大蒙麥斯應力值做為評估手術的輸出回應，觀察作用於手術之影響，從中找出最佳的控制參數配合給予醫師做一有效建議與評估。
　　在田口法望小特性的分析結果中，從回應圖可顯示脛骨植入物類別與膝內翻角度為手術研究中最顯著的控制因子，其因子之改變確實會造成人工脛骨元件上應力之增減；而在脛骨後傾角部分則對手術之影響較不顯著。另外分析結果最後得到針對模擬病患的最佳手術因子組合，為使用微曲面接觸面的脛骨植入物加裝脛骨襯墊之類別，與膝內翻矯正為5°之過度矯正，並搭配脛骨後傾角5°之切角。
　　研究也依照最佳因子組合做一實驗分析確認，結果證實此組合確實能得到最佳之回應值。但分析結果產生之應力數據仍然超過PE塊本身的降伏強度，且在研究分析中，不論何種膝關節對位或接觸面型態，最大蒙麥斯應力值皆產生於內部，其也呼應了文獻所提及之聚乙烯元件是由內部開始損壞之推測。故在綜合以上之論點時，可發現當選用膝關節治療方式時，單髁人工膝關節是否適用值得深思。

關鍵字

單髁人工膝關節 ； 田口法 ； 脛骨元件 ； 蒙麥斯應力

並列摘要

In the tendency of the history of unicompartmental knee arthroplasty (UKA), we could find that the successful rate had been raised with the continuous advanced surgical operation. However, the surgical operation does not completely succeed during the clinical manifestation. In order to getting better performance of the UKA, we do more track and research to find the failure factor of the surgical operation. Beside, most research of the UKA is approached for the separated subject; And few for the integrate subject. Therefore, how to integrate these affected parameter to fine the marked one is the importance goal to mature the UKA.
This research of the polyethylene (PE) tibial component made up with the different geometric form and material is to analyze all kind of the knee joint location setting. Apply the Taguchi method to simulate the situation of the varus knee 7.5° and tibial plateau posterior slope 7.5° with the factors of PE type、varus knee、tibial plateau posterior slope and set the error factor. Make max von Mises stress which is produced from the tibial component to be the result of the evaluating surgical operation and survey the influence to find the best control parameter for the effective suggestion to the doctor.
From the analysis result of thesmall-is-better (SB), PE type and varus knee are the most marked control parameters which will result in the stress change of tibial component while the factor change and tibial plateau posterior slope has only less influence to it. More then that, the best composition of the operational factor to the simulation patient is to use Metal-Backing and overcorrection of varus knee 5°and to assort tibial plateau posterior slope 5°.
Analysis base on the best factor composition approves that the this composition could get the best result. But the stress data of the analysis result still exceed the yield stress of the PE. No matter what kind of the knee alignment or PE type, max von Mises stress is produced from inside and which match the conjecture that the PE is destroyed from inside. Integrate above opinions, it is worth to think deeply if the unicompartmental knee prosthesis (UKP) is suitable when choosing the cure way of the knee joint.

並列關鍵字

unicompartmental knee arthroplasty ； Taguchi method ； tibial component ； von Mises stress

參考文獻

[5] 林林晉、楊培銘、謝博生，單髁人工膝關節置換手術適應症之爭議，台灣醫學，第10卷，第5期，2006，第636-640頁。

[32] 劉建緯，單髁人工膝關節脛骨植入物之生物力學研究-有限元素分析，國立台北科技大學機電科技研究所博士論文，台北，2008。

[2] J.N. Insall and P. Aglietti, “A five to seven-year follow-up of unicondylar arthroplasty,” J Bone Joint Surg, vol. 62-A, 1980, pp. 1329-1337.

[3] B.D. Springer, R.D. Scott and T.S. Thornhill, “Conversion of failed unicompartmental knee arthroplasty to TKA.” Clin Orthop Rel Res 446, 2006, pp. 214-220.

[4] B. Saccomanni, “Unicompartmental knee arthroplasty: a review of literature,” Clin Rheumatol., Vol. 29, 2010, pp. 339-346.