足部與膝部矯具對內側膝部退化性關節炎患者步態和肌肉作動之影響

Abstract

研究目的: 本篇研究之目的，在於探討外側楔型墊和膝部矯具對於內側退化性關節炎患者在生物力學和步態方面的效益。除了研究一般健康年長者和退化性關節炎患者步態之動力學和運動學的差異外，也同時探索這兩者間表面肌電圖的表現。本實驗利用程式模擬步態的表現來計算步態的各個關節之角度、運動振動幅度、關節受力、關節力矩等重要參數，和肌肉作動的表徵，希望得到的結果可供臨床人員作為了解退化性關節炎病理變化和病態步態的呈現之用，也可以作為臨床決斷時重要的參考資料。 實驗方法和設計: 本實驗收集三十位受測者的資料，依據症狀、理學檢查和醫學影像檢查分為健康控制組 (平均年紀63.3 ± 3.5 歲; 平均身體組成指數, 23.4 ± 1.9) 和關節退化實驗組 (平均年紀67.5± 7.2 歲; 平均身體組成指數, 24.7 ±3.4)。這兩組人員分別先利用動作分析系統，收集基礎的步態參數 (步長、步距、步頻和步寬等)，再收集運動學和動力學參數和肌電圖的數值; 實驗組除了基礎資料外，還必須就使用外側楔型墊和膝部矯具收集自選步行速度時各參數的差異。另外關節角度的評估和本體感覺的測試也一併於實驗中收集並進行分析。 結果: 在此篇研究中發現下列參數有顯著性的差異(1)實驗組和控制組在步態擺盪期的呈現較小的最大膝關節彎曲角度和步態站立期較小的關節振動幅度。而實驗組在使用膝部矯具的情況下，呈現較小的最大膝關節彎曲角度和膝關節運動振幅。(2) 實驗組和控制組在膝部內收力矩和髖部伸展力矩的表現上，有顯著的組間差異。(3)在共同收縮指數上的表現，實驗組在外側部分(VLLH and VLLG)比內側部分得到較大的數值.(4)最後在步態參數的表現上，實驗組和控制組間有明顯較慢的步行速度、較低的步頻和較長的步行滯留時間的差距; 而在本體感覺的測試中，膝部矯具組也表現出和其他組別不同的顯著差異。 結論: 當我們比較運動學、動力學甚至是表面肌電圖的表現後，從結果可以確認使用矯具當作退化性關節炎患者的介入治療，確實對這一類患者有相當程度的幫助。使用足部或膝部矯具不僅可以改善疾病對於步態的影響，也提供膝關節力學環境的改善和保護。因此，足部或膝部矯具或許可以為退化性關節炎患者提供一種非侵入性、低風險而具療效的治療。但臨床人員也必須注意矯具使用時所產生的不適和依賴性，以達到更好的治療成果。

Abstract: Objective: The purpose of this study was to determine the possible biomechanical mechanisms resulting in effectiveness of the lateral wedge foot orthoses and valgus knee orthoses for patients with medial compartment knee osteoarthritis. And sEMG data were also investigated to clarify subtle muscle activation pattern in patients. A multi-segment model was developed to investigate kinematic and kinetic changes that contribute to knee osteoarthritis. To provide comprehensive information included joint mechanics, muscle activation pattern and proprioception of the patients among orthotics interventions. Design and setting: All participants were separated into two groups depending on symptoms and physical examinations. Fifteen elders with medial compartment knee OA (7 males and 8 females) and fifteen matched controls (3 males and 12 females) were recruited in this research to collect the kinetic, kinematic and surface EMG data to analyze the biomechanical alterations in different orthotic conditions. The Orthotic group was tested the effects of 4° and 8° lateral wedges and valgus knee orthosis during the gait cycle. Symptoms, functional assessment and proprioception test were also assessed in the gait laboratory. Main outcome measurement: (1) Gait parameters: stride length, width, gait speed, gait cycle time (2) Kinematics variables: peak knee flexion angle and excursion; static knee valgus angle and knee valgus excursion (3) Kinetics variables: ankle, knee and hip joint moment, COP deviation (∆COP) (4) Muscle activation pattern: % of the MVIC, co-contraction index (CI) Results: the average age of Knee OA group was 67.5 years (±7.2) and the mean BMI was 24.7 ±3.4. The average age of the subjects in age-matched group was 63.3 years (±3.5) and the mean BMI was 23.4 ± 1.9. The OA knee group showed (1) significant lower walking speed, lower cadence, and longer stride time were found while compared to the control group. And there was a statistically significant difference between the KO and the shoes-only condition in proprioception test. (2) The OA group revealed significant smaller peak knee flexion angle during swing phase and knee flexion excursion during stance phase compared to the controls. The KO condition also revealed smaller peak knee flexion angle during swing phase and smaller flexion excursion during stance phase. (3) The significant differences were found in knee adduction and hip extension moment. The peak knee adduction moment decreased 14.7 % in the W4 condition, 24.4 % in the W8 and 17.1 % in the KO condition. (4) The OA group generally had larger values in lateral co-contraction index (VLLH and VLLG) than medial side significantly. Conclusion: When the kinematics and kinetics data as well as muscle activities in patients with knee OA were assessed in this study, the results showed that they can benefit from orthotic interventions. With the use of lateral wedge orthoses or valgus knee orthoses, patients can improve joint mechanical environment and provide appropriate protection to those who suffer from medial compartment knee OA. The results support the hypotheses and indicate orthoses as a non-surgical, low-risk and less expensive treatments for patients. There are still unanticipated effects and problems among orthotic treatments needed to solve. And the long-term effects of the orthoses await further study.