功能性鞋墊被廣泛應用於下肢骨骼肌肉產生疼痛問題的病患如扁平足或膝關節炎。但是有關功能性鞋墊能使這些病人的症狀減輕的原因、步態改變的生物力學機轉都還不是很清楚且也未有定論，而在這些探討中，有許多的研究只針對足部結構做生物力學上的分析，卻未對整個下肢做整體的探討，而且大多數的相關研究報告都以正常人做為受測者，皆未針對病人做進一步的相關生物力學報告。所以本研究計畫希望透過三維的動作分析與測力板系統來瞭解功能性矯正鞋墊對扁平足與膝關節炎病人的影響並探討其機轉，以作為日後改進或研發的重要依據。
此外如何提出有效的估算矯正鞋墊的使用效果與舒適度，一直是生物力學與從事臨床醫療者極力尋找的目標，然而由於目前並無法直接量測肌肉骨骼內力，必須藉由其他的感測訊號推估，因此希望透過實驗的人體動作資料以及藉由生物力學肌肉骨骼系統模擬軟體，模擬推估各個肌肉骨骼系統受力，以更清楚地瞭解病人使用功能性鞋墊後，鞋墊與人體肌肉骨骼系統相互影響與作用。
因此，本研究的目的為：（一）探討病人在穿著功能性鞋墊前後在步態週期的生物力學，以瞭解在穿著功能性鞋墊後對人體的肌肉骨骼系統的影響機制。（二）發展建立人體的三維步態生物力學與功能性鞋墊模擬模型，模擬穿著功能性鞋墊前後的人體步態。（三）利用此模擬模型探討病人在穿著功能性鞋墊後，改變相關鞋墊設計的參數，對病人步態肌肉骨骼系統的影響。
本計劃由十一位先天性扁平足者及十二位雙膝皆為退化性膝關節炎患者參與研究。使用三度空間動態分析系統與力板系統分別收集三組：裸足組、穿鞋子組和穿鞋子與鞋墊組三種狀況的步態，再利用計算軟體(Orthotrak 6.0、Matlab)和統計軟體(SPSS 13.0)分析每位受測者步態週期中的時間空間參數、下肢關節的運動學與動力學資料。最後使用軟體 (ADAMS-LifeMOD )進行模擬。
有關扁平足患者的研究結果顯示在穿鞋子與鞋墊組和穿鞋子組踝關節背屈角度和力矩峰值增加，而踝關節蹠屈角度和力矩峰值減少。此外穿鞋子與鞋墊組穿鞋子組都增加膝內翻的力矩峰值。矯正鞋墊對膝關節和髖關節影響很小，比較穿鞋子與鞋墊組和穿鞋子組二種狀況的步態時，則無顯著差異。結果顯示，此研究中的矯正鞋墊鞋可能有益扁平足患者的踝關節。由於穿鞋子與鞋墊組和穿鞋子組二種狀況的步態之間並無顯著差異，所以需進一步研究足與矯正墊的相互作用與影響。
在退化性膝關節炎患者的研究結果顯示穿鞋子與鞋墊組膝關節屈曲角度峰值、踝關節背屈和外轉角度峰值增加，但踝關節內轉角度峰值減少。穿鞋子與鞋墊組和穿鞋子組二種狀況皆顯著減少趾外偏角(toe-out)。此外穿鞋子與鞋墊組踝關節內轉力矩峰值減少但膝內翻力矩峰值無顯著差異。由於結果顯示趾外偏角減少、膝內翻力矩峰值增加的趨勢，此種矯正鞋墊可能不適合退化性膝關節炎患者使用。
模擬模型的地面反作用力與實驗值(穿鞋子與鞋墊組)的變化趨勢類似。模擬結果顯示地面反作用力峰值易受接觸元素的硬度影響。模擬結果顯示當改變轉接器元素的黏彈性時地面反作用力峰值變異量大。鞋子高度是影響模擬模型的地面反作用力峰值主要因子。與實驗數據比較，模擬數據顯示在穿鞋子與鞋墊組和裸足組二種情況下，踝、膝和髖關節角度與實驗值非常類似，各關節角度的實驗峰值與模擬數據峰值之間的差異分別在5度內。比較模擬數值和實驗數值的踝和膝關節力矩峰值，其誤差百分比都在3~20%內。不過，髖關節力矩峰值的誤差百分比則高於30%。由於模擬與實驗數據趨勢一致，所以此模擬模型的建立方法是可行的。但此模擬模型準確度受限於鞋墊的特性和人體計測資料(例如髖關節中心)。本研究模型可以藉由改變矯正鞋墊的特性與進一步加入肌肉模型以便有效地建立發展或改善患者的矯正鞋墊。

Foot orthotics is widely prescribed for the patients with diseases in the lower extremity such as osteoarthritis and flatfoot. However, the biomechanical effects of the orthotics used in the clinical treatment are not yet fully understood. Furthermore, the published literature focuses principally on the effects of orthotic devices on the foot structure rather than on the lower limbs. Last but not least, the biomechanical investigations reported in the literature are invariably performed using healthy subjects rather than patients.
In order to propose effective estimation of the validity and comfort of the use of functional insoles, using the simulation software in development of computer models to emulate human gait would understand more about loads on the bone, joints and muscles. Not only the models can be used to better understand the physical properties of the shoes and insoles regarding the potential of correcting foot structure, but it can study the mechanics of interaction between the insoles and the body.
The purposes of this study are: (1) to evaluate the biomechanical effects of orthotic devices on the gait patterns of patients with flatfoot and osteoarthritis, (2) to develop and validate a three-dimensional simulation model of human walking with orthotic devices. (3) to investigate the effects to the users when alternating the parameters of the related orthotic devices.
Eleven adults with flatfoot deformities and twelve adults with knee osteoarthritis (OA) were recruited. For each participant, kinematic and kinetic data were measured under three test conditions, i.e. walking barefoot, walking with shoes, and walking with shoes and insoles. During each test, the participants’ gaits patterns were recorded and analyzed using a motion analysis system, two Kistler force plates and EVaRT software. And then, simulations were performed by ADAMS-LifeMOD.
The results of patients with flatfoot showed that walking with shoes and insoles and walking with shoes conditions increased the peak ankle dorsiflexion angle and moment, and also reduced the peak ankle plantarflexion angle and moment. Furthermore, walking with shoes and insoles and walking with shoes conditions increased the peak knee varus moment. The effects of the orthoese on knee and hip were minimal and no significant differences were observed between walking with shoes and insoles and walking with shoes. The results suggested that the foot insoles and shoes developed in this study might benefit the ankle joint in patients with flat feet. In view of the minimal changes between walking with shoes and insoles and walking with shoes, further studies may be required to clarify the interaction between the foot and the insole/shoe.
In the results of patients with osteoarthritis (OA), walking with shoes and insoles significantly increased peak knee flexion angle, and peak dorsiflexion and external rotation angles of the ankle, but reduced the peak ankle internal rotation angle. Both walking with shoes and insoles and walking with shoes conditions significantly reduced the toe-out angle. Furthermore, the peak ankle internal rotation moment was significantly reduced in walking with shoes and insoles. However, no significant difference was observed in the peak knee varus moment. In view of the significantly decreased toe-out angle of the foot and increasing trend existed in knee varus moment, the use of the shoes and insoles may be unsuitable for OA knee patients.
The peak ground reaction forces (GRF) of the simulation model were similar to the measured forces under the walking with shoes and insoles condition. Simulations showed that peak GRF was sensitive to stiffness of the contact element (between the ground and the shoes), although these changes were small. The results showed that the peak GRF were variable when the stiffness and damping properties of the bushing elements (between the insole and the foot) were changed. The increase in the shoes-height results in the most dominates reduction on peak GRF. Comparison with the experimental data, the simulated angular excursions in the three motion plane at the ankle, knee and hip joint were highly correlated with the measured values under walking with shoes and insoles condition. The differences of the values between the simulated and measured joint angle were below 5 degrees. The percentage errors of peak ankle and knee joint moments between simulated and measured values were within 3~20%. However, the percentage errors of peak hip joint moments between simulated and measured values were higher than 30%. Based on the reasonable agreement between simulated data and experimental values, it can be concluded that the modeling approach is viable. The accuracy of this approach is mainly limited by the characteristics of the shoes-insoles and anthropometry of the subjects (e.g. hip center). The current model allows alterations of the properties of the shoes-insoles and advances applications with muscle model to develop or improve orthoses for specific patients efficiently.

Altman, R.D., Hochberg, M.C., Moskowitz, R.W. and Schnitzer, T.J., Recommendations for the medical management of osteoarthritis of the hip and knee: 2000 update. Arthritis Rheum. 43, 1905-1915, 2000.
Barry R.J., Scranton P.E., Flatfoot in children. Clin. Orthop. 181:68-75, 1983.
Bertani, A., Cappello, A., Benedetti, M.G., Simoncini, L., Catani, F., Flat foot functional evaluation using pattern recognition of ground reaction data. Clinical Biomechanics 14, 484–493, 1999.
Branthwaite, H.R., Payton, C.J., Chockalingam, N., The effect of simple insoles on three-dimensional foot motion during normal walking. Clinical Biomechanics 19, 972–977, 2004.
Broch, N.L., Wyller, T., and Steen, H., Effects of heel height and shape on the compressive load between Foot and Base-A graphic analysis of principle. Journal of the American Podiatric Medical Association. 94, 461-469,2004.
Brown, G.P., Donatelli, R., Catlin, P.A., Wooden, M.J., The effect of two types of foot orthoses on rearfoot mechanics. The Journal of Orthopaedic and Sports Physical Therapy 21, 258, 1995.
Butler, R.J., Marchesi, S., Royer, T. and Davis, I.S., The effect of a subject-specific amount of lateral wedge on knee mechanics in patients with medial knee osteoarthritis. Journal of Orthopaedic Research. 25, 1121-1127, 2007.
Cheung, J.T. and Zhang, M., A 3-dimensional finite element model of the human foot and ankle for insole design. Archives of Physical Medicine and Rehabilitation. 86, 353-358, 2005.
Clarke, T. E., Frederick, E. C. and Cooper, L. B. , The effects of shoe cushioning upon ground reaction forces in running. International Journal of Sports Medcine 4, 247-251, 1983.
Crenshaw, S.J., Pollo, F.E. and Calton, E.F., Effects of lateral-wedged insoles on kinetics at the knee. Clinical orthopaedics and related research. 375, 185-192, 2000.
Clement, D.B., Taunton, J.E., Smart, G.W., Achilles tendinitis and peritendinitis: etiology and treatment. The American Journal of Sports Medicine 12, 179, 1984.
Davis, M.A., Ettinger, W.H., Neuhaus, J.M. and Mallon, K.P., Knee osteoarthritis and physical functioning: evidence from the NHANES I Epidemiologic Followup Study. The Journal of rheumatology. 18, 591-598, 1991.
Degoede, K. M., Ashton-Miller, J. A., Biomechanical simulations of forward fall arrests: effects of upper extremity arrest strategy, gender and aging-related declines in muscle. Journal of Biomechanics 36, 413–420, 2003.
Eng, J.J., Pierrynowski, M.R., The effect of soft foot orthotics on threedimensional lower-limb kinematics during walking and running. Physical Therapy 74, 836–844, 1994.
Even-Tzur, N., Weisz, E., Hirsch-Falk ,Y., Role of EVA viscoelastic properties in the protective performance of a sport shoe:Computational studies.Bio-Medical Materials and Engineering 16,289–299, 2006.
Ferciot C.F., The etiology of developmental flatfoot. Clin Orthop 85:7–10, 1972.
Felson, D.T. and Zhang, Y., An update on the epidemiology of knee and hip osteoarthritis with a view to prevention. Arthritis & rheumatism 41, 1343-1355, 1998.
Franco, A.H., Pes cavus and pes planus: analyses and treatment. Physical Therapy 67, 688, 1987.
Franz, J.R., Dicharry, J., Riley, P.O., Jackson, K., Wilder, R.P. and Kerrigan, D.C., The influence of arch supports on knee torques relevant to knee osteoarthritis. Medicine & Science in Sports & Exercise. 40, 913-917, 2008.
Genova, J.M., Gross, M.T., Effect of foot orthotics on calcaneal eversion during standing and treadmill walking for subjects with abnormal pronation. The Journal of orthopaedic and sports. 30(11), 664-75, 2000.
Gerritsen, K.G. M., van den Bogert, A.J. and. Nigg, B. M. J., Direct dynamics simulation of the impact phase in heel-toe running. Journal of Biomechomcs.28, 661 -668, 1995.
Gilchrist, L. A. and Winter, D. A., A two-part, viscoelastic foot model for use in gait simulations. Journal of Biomechanics. 29, 795-798, 1996.
Gok, H., Ergin, S., Yavuzer, G., Kinetic and kinematic characteristics of gait in patients with medial knee arthrosis. Acta Orthopaedica Scandinavica. 73, 647– 652, 2002.
Gross, M.L., Davlin, L.B., Evanski, P.M., Effectiveness of orthotic shoe inserts in the long-distance runner. The American Journal of Sports Medicine 19, 409, 1991.
Guccione, A.A., Felson, D.T. and Anderson, J.J., Defining arthritis and measuring functional status in elders: methodological issues in the study of disease and physical disability. American Journal of Public Health. 80, 945-949, 1990.
Hibbeler, R.C., Engineering Mechanics: Dynamics. :Prentice Hall, 2002.
Hong , X., Masami, A., Shuichi, K., Kazuhiko, Y., Hideo, K., Effect of shoe Mmodifications on center of pressureand in-shoe plantar pressures. American Journal of Physical Medicine & Rehabilitation 78 , 516-524, 1999.
Hunt, A.E., Smith, R.M., Mechanics and control of the flat versus normal foot during the stance phase of walking. Clinical Biomechanics 19, 391–397, 2004.
Hurwitz, D.E., Ryals, A.B., Case, J.P., Block, J.A., Andriacchi, T.P.,. The knee adduction moment during gait in subjects with knee osteoarthritis is moreclosely correlated with static alignment than radiographic disease severity; toe out angle and pain. Journal of Orthopaedic Research 20, 2002.
Ilahi, O.A., Kohl Iii, H.W., Lower extremity morphology and alignment and risk of overuse injury. Clinical Journal of Sport Medicine 8, 38, 1998.
Kane, T. and Levinson, D., Dynamics: Theory and pplications. :McGraw-Hill , 1985.
Kaufman, K.R., Brodine, S.K., Shaffer, R.A., Johnson, C.W., Cullison, T.R., The effect of foot structure and range of motion on musculoskeletal overuse injuries. The American Journal of Sports Medicine 27, 585, 1999.
Khodadadeh, S, Welton E. A., Gait studies of patients with flat foot. The Foot 3, 189-193, 1993.
Kitaoka, H.B., Luo, Z.P., Kura, H., An, K.N., Effect of foot orthoses on 3-dimensional kinematics of flatfoot: a cadaveric study. Archives of Physical Medicine and Rehabilitation 83, 876–879, 2002.
Kakihana, W., Akai, M., Nakazawa, K., Takashima, T., Naito, K. and Torii, S., Effects of laterally wedged insoles on knee and subtalar joint moments. Archives of physical medicine and rehabilitation. 86, 1465-1471, 2005.
Kerrigan, D.C., Lelas, J.L., Goggins, J., Merriman, G.J., Kaplan, R.J. and Felson, D.T., Effectiveness of a lateral-wedge insole on knee varus torque in patients with knee osteoarthritis 1. Archives of physical medicine and rehabilitation. 83, 889-893, 2002.
Kirkley, A., Webster-Bogaert, S., Litchfield, R., Amendola, A., MacDonald, S., McCalden, R.et al., The effect of bracing on varus gonarthrosis. The Journal of Bone and Joint Surgery. 81, 539-548, 1999.
Ledoux W.R., Hillstrom H.J., Acceleration of the calcaneus at heel strike in neutrally aligned and pes planus feet. Clinical Biomechanics Vol. 16 (7), 608-13, 2001.
Ledoux W.R., Hillstrom H.J., The distributed plantar vertical force of neutrally aligned and pes planus feet. Gait & Posture Vol. 15 (1), pp. 1-9, 2002.
Lemmon, D.,Shiang, T.Y., Hashmi, A., Ulbrecht, J.S. and Cavanagh, P.R., The effect of insoles in therapeutic foot wear a finite element approach. Journal of Biomechanics 30, 615–620, 1997.
Lin, C.J., Lai, K.A., Kuan, T.S. and Chou, Y.L., Correlating factors and clinical significance of flexible flatfoot in preschool children. Journal of Pediatric Orthopaedics. 21, 378, 2001.
Lindenfdd, T.N., Hewett, T.E. and Andriacchi, T.P., Joint loading with valgus bracing in patients with varus gonarthrosis. Clinical orthopaedics and related research. 344, 290-297, 1997.
Maly, M.R., Culham, E.G. and Costigan, P.A., Static and dynamic biomechanics of foot orthoses in people with medial compartment knee osteoarthritis. Clinical Biomechanics. 17, 603-610, 2002.
McClay, I., Manal, K., Three-dimensional kinetic analysis of running: significance of secondary planes of motion. Medicine & Science in Sports & Exercise 31, 1629, 1999.
McCulloch, M.U., Brunt, D., Vander Linden, D., The effect of foot orthotics and gait velocity on lower limb kinematics and temporal events of stance. Journal of Orthopaedic & Sports Physical Therapy 17, 2–10, 1993.
Messier, S.P., Pittala, K.A., Etiologic factors associated with selected running injuries. Medicine & Science in Sports & Exercise 20, 501, 1988.
Morley, A.M., Knock-kcee in children. Br. Med. J. 26:976-979, 1957.
Mundermann, A., Nigg, B.M., Humble, R.N., Stefanyshyn, D.J., Foot orthotics affect lower extremity kinematics and kinetics during running. Clinical Biomechanics 18, 254–262, 2003.
Mündermann A, Nigg BM, Humble RN, Stefanyshyn DJ, Orthotic comfort is related to kinematics, kinetics, and EMG in recreational runners. Medicine and science in sports and exercise. 35, 1710-9, 2003.
Nawoczenski, D.A., Cook, T.M., Saltzman, C.L., The effect of foot orthotics on three-dimensional kinematics of the leg and rearfoot during running. The Journal of Orthopaedic and Sports Physical Therapy 21, 317, 1995.
Nester, C.J., Van Der Linden, M.L., Bowker, P., Effect of foot orthoses on the kinematics and kinetics of normal walking gait. Gait & Posture 17, 180–187, 2003.
Nigg, B.M., Herzog, W., Read, L.J., Effect of viscoelastic shoe insoles on vertical impact forces in heel-toe running. The American Journal of Sports Medicine 16, 70, 1988.
Nigg, B. M., Bahlsen, H. A., Luethi, S. M. and Stokes, S., The influence of running velocity and midsole hardness on external impact forces in heel-toe running. Journal of Biomechanics 20, 951-959, 1987.
Nigg, B. M., Liu, W., The effect of muscle stiffness and damping on simulated impact force peaks during running. Journal of Biomechanics 32, 849-856, 1999.
Noll, K.H., The use of orthotic devices in adult acquired flatfoot deformity. Foot and Ankle Clinics of North America 6, 25–36, 2001.
Ogata, K., Yasunaga, M. and Nomiyama, H., The effect of wedged insoles on the thrust of osteoarthritic knees. International orthopaedics. 21, 308-312, 1997.
Olsen, T.R., Saidei, M.R., The evolutionary basis of some clinical disorders of the human foot: a comparative survey of the living primates. Foot Ankle Int. 3, 322–341, 1983.
Oliveria, S.A., Felson, D.T., Reed, J.I., Cirillo, P.A., Walker, A.M., Incidence of symptomatic hand, hip, and knee osteoarthritis among patients in a health maintenance organization. Arthritis Rheum;38:1134-41, 1995.
Rattanaprasert, U., Smith, R., Sullivan, M., Gilleard, W., Three-dimensional kinematics of the forefoot, rearfoot, and leg without the function of tibialis posterior in comparison with normals during stance phase of walking. Clinical Biomechanics 14, 14–23, 1999.
Rao, U.D., Joseph, B., The influence of footwear on the prevalence of flatfoot: a survey of 2300 children. Journal of Bone and Joint Surgery. Vol 74-B(4), 525-527, 1992.
Roche, C., Mattingly, B., Vishwas Talwalkar, M.D., Tylkowski, C., Stevens, D.B., Hardy, P.A., Pienkowski, D., Three-Dimensional hindfoot motion in adolescents with surgically treated unilateral clubfoot. Journal of Pediatric Orthopaedics 25, 630, 2005.
Rodgers, M.M., Dynamic foot biomechanics. Journal of Orthopaedic & Sports Physical Therapy 21, 306–316, 1995.
Rodrigues, P.T., Ferreira, A.F., Pereira, R.M.R., Bonfa, E., Borba, E.F. and Fuller, R., Effectiveness of medial-wedge insole treatment for valgus knee osteoarthritis. Arthritis Care & Research. 59, 603-608, 2008.
Rose, G.K., Pes planus. In: Jahss, M.H. (Ed.), Disorder of the Foot and Ankle. WB Saunders, Philadelphia, pp. 892–919, 1991.
Sasaki, T. and Yasuda, K., Clinical evaluation of the treatment of osteoarthritic knees using a newly designed wedged insole. Clinical orthopaedics and related research. 221, 181-187, 1987.
Sachithanandam V. and Joseph B., The influence of footwear on the prevalence of flat foot: A survey of 1846 skeletally mature persons. The Journal of Bone and Joint Surgery 77(2), 254-257, 1995.
Schipplein, O.D. and Andriacchi, T.P., Interaction between active and passive knee stabilizers during level walking. Journal of orthopaedic research. 9, 113-119, 1991.
Sharma, L., Hurwitz, D.E., Thonar, E. J-M. A., Sum, J.A., Lenz, M.E., Dunlop, D.D.et al., Knee adduction moment, serum hyaluronan level, and disease severity in medial tibiofemoral osteoarthritis. Arthritis & Rheumatism. 41, 1233-1240, 1998.
Shimada, S., Kobayashi, S., Wada, M., Uchida, K., Sasaki, S., Kawahara, H.et al., Effects of disease severity on response to lateral wedged shoe insole for medial compartment knee osteoarthritis. Archives of physical medicine and rehabilitation. 87, 1436-1441, 2006.
Stacoff, A., Reinschmidt, C., Nigg, B.M., Van Den Bogert, A.J., Lundberg, A., Denoth, J., Stussi, E., Effects of foot orthoses on skeletal motion during running. Clinical Biomechanics 15, 54–64, 2000.
Stell, J.F., Buckley, J.G., Controlling excessive pronation: a comparison of casted and non-casted orthoses. The Foot 8, 210–214, 1998.
Thomas, R.H., Resnick, D., Compartment evaluation of osteoarthritis of the knee: a comparative study of available diagnostic modalities. Radiology. 116, 585-594, 1975.
Tohyama, H., Yasuda, K. and Kaneda, K., Treatment of osteoarthritis of the knee with heel wedges. International orthopaedics. 15, 31-33, 1991.
Toda, Y. and Tsukimura, N., A six-month followup of a randomized trial comparing the efficacy of a lateral-wedge insole with subtalar strapping and an in-shoe lateral-wedge insole in patients with varus deformity osteoarthritis of the knee. Arthritis & Rheumatism. 50, 3129-3136, 2004.
Verdejo, R. and Mills, N.J., Heel–shoe interactions and the durability of EVA foam running-shoe midsoles. Journal of Biomechanics 37 , 50–53, 2004.
Williams, D.S., McClay, I.S., Measurements used to characterize the foot and the medial longitudinal arch: reliability and validity. Physical Therapy 80, 864, 2000.
Lu, T.W., 「傾斜地面特性對滑倒之影響評估」，勞工安全衛生研究所 91 年度研究報告 IOSH91-H344。2002.
Lou, S.Z., 「向前跌倒時上肢的生物力學分析與模擬」，國科會報告93-2213-E-324-009。2004.