Development of a Physical Therapy System for Enhancement of Balance Ability Seunghoon Lee 1, Younggeun Choi 1, Hyewon Lee 1, Wonsup Lee 1, Taekho You 1, Myounghwan Ko 2, Jongkwan Park 2, Minjung You 2, Heecheon You 1 1 Department of Industrial and Management, Pohang 2 Department of Clinical Trial Center, Chonbuk National University Hospital, Jeonju ABSTRACT Objective: 본연구는노인이나편마비환자등의균형능력을평가하고균형장애를치료할수있는기능성게임기반물리치료시스템을개발하고자한다. Background: 기존물리치료방법은단순하고지루한동작을반복수행하는것으로서환자의재활의지를저하시킬여지가있으므로, 효과적인물리치료를위해치료동기및흥미를유발시키는방법이요구된다. 기존균형장애의평가는임상의의주관적판단에의하여이루어지고있으며정량적평가체계가미흡한실정이다. Method: 본연구는국내외선행연구조사, 기존제품조사, 그리고전문가자문을통해기존균형훈련물리치료시스템의문제를파악하고새로운아이디어를제안하였다. 제안된아이디어는실용성및임상효과측면에서평가되었으며, 최종제품 concept 이도출되었다. Results: 본연구를통해개발된기능성게임기반의균형훈련물리치료시스템아이디어는사용성, 만족도, 임상적활용성, 치료효과측면에서보다효과적인균형훈련방법을제공할것으로기대된다. Conclusion: 본연구에서개발될신체균형능력향상을위한기능성게임물리치료시스템은기존의물리치료장비들과비교하여치료의효율측면에서우수한효과가기대된다. 또한, 가정에서도치료사없이손쉽고재미있게자가치료를진행할수있어지속적치료가가능하다. Application: 제안된균형훈련물리치료시스템아이디어는재활의학센터, 요양원, 그리고가정등에서사용될수있도록상용장비로개발되고있으며, 시제품이개발되면균형장애환자를대상으로사용성및임상적활용성등이평가될예정이다. Keywords: Balance disorder, Balance therapy, Physical therapy, Serious game 1. Introduction 동적균형능력 (dynamic balancing) 은신체활동시균형을유지하고자세를제어 (postural control) 하는핵심적인역할을한다 (Hrysomallis, 2011). 특히, 동적균형능력은움직임을지속하는데필요한주요한요소이므로, 동적균형능력의감소는일상생활중낙상위험을크게증가시킬수있다 (Isles et al., 2002). 하지만균형능력은나이, 근골격계기능저하, 그리고감각기관기능저하등의다양한원인에의하여감퇴될수있다. 균형능력의감퇴는일상생활에서많은제약을동반하며, 이러한제약은개인의삶의질을현격하게떨어뜨릴수있다 (Legter, 2002). 따라서균형능력의회복을위하여물리치료사와운동처방사등에의해재활훈련이활발히시행되고있다. 균형능력향상을위한재활훈련에있어서재활동기는재활의효과를결정하는중요한요소로작용할수있다. 김이영 (2006) 은장애인의재활동기와재활성과의관계연구에서높은재활동기는임상적영역 ( 장애증상 ), 기능적영역 ( 기능과작업태도 ), 그리고주관적경험영 역 ( 삶의질 ) 에긍정적영향을미친다고밝혔다. 기존의균형훈련은불안정판을사용하여균형유지능력을향상시키는훈련과특정동작 (e.g., single-leg stance, single-leg hop) 을반복적으로수행함으로써균형능력을향상시키는운동치료등이있다. 이러한재활훈련은부분적으로균형능력및고유감각을회복시킬수있었지만 (Holmes & Delahunt, 2009), 단순한동작을반복적으로수행하므로치료대상자에게있어지루함을유발하고치료동기및흥미를떨어뜨릴수있다 (Gil-Gómez et al., 2011). 이러한치료동기및흥미의결여는치료의효율을저하시킬수있으므로노인이나환자의재활의지를지속적으로고취시킬수있는새로운균형훈련전략이필요하다. 최근재활치료를위한도구로서기능성게임 (serious games) 이대두되고있으며기능성게임을접목한균형훈련연구가활발히수행되고있다. 기능성게임은게임의본질적인순기능인재미요소와함께건강, 교육등과같은목적을동시에이루고공공과개인들에게도움을제공하는게임이다. Brumels et al. (2008) 은균형능력의향상과재활의지측면에서기능성게임기반균형훈련과기존재활훈련을비교평가하였다. 기존재
활훈련에비하여게임기반재활훈련은균형능력을향상시키는데더욱효과적이었으며, 이와더불어기능성게임기반균형훈련은훈련대상자로하여금재미있는균형훈련을수행하도록유도할수있음을밝혔다. Deustch et al. (2008) 은가정용비디오게임콘솔인 Wii Sports TM (Nintendo of America, Redmond, WA, USA) 을사용하여뇌성마비환자의재활치료효과를연구한결과, 뇌성마비환자의자세제어능력과기능적이동성 (functional mobility) 이동시에향상될수있음을밝혔다. 본연구는선행연구조사, 기존균형훈련제품조사, 그리고전문가자문을통해기존균형훈련물리치료시스템의문제를파악한다. 또한새로운균형훈련시스템아이디어제안을통해노인이나편마비환자등의균형능력을평가하고균형장애를치료할수있는기능성게임기반물리치료시스템을개발하고자한다. Figure 1. Research procedure 2. Method 3. Results 기능성게임기반균형훈련시스템개발을위한아이디어는균형훈련제품조사, 선행연구조사, 균형훈련시스템설계요소추출및균형훈련시스템아이디어개발을통해도출되었다 (Figure 1). 균형훈련제품조사는균형훈련시스템개발에적용될수있는설계요소들을 benchmarking하기위해다양한균형훈련제품및시스템을분석하였다. 선행연구조사는균형능력향상에효과적인훈련시스템개발및기존균형훈련과의차별화방안을수립하기위하여다양한국내외논문을분석하였다. 균형훈련시스템설계요소추출은균형훈련시스템아이디어개발시필요한설계요소들을추출하기위해기존제품및선행연구의핵심가치를파악하고전문가자문을통해임상적효용성을확인하였다. 마지막으로균형훈련시스템아이디어는파악된제품설계요소들에기반하여개발될수있었다. 제품아이디어개발을위해서는 brainstorming과같은일반적인방법이사용되었다. 기능성게임기반균형훈련시스템개발을위하여 6 가 지균형훈련제품을선정하여장단점분석이수행되었다. 기존제품중무전력제품 (No. 1 ~ 3, Table 1) 들은가볍고 크기가작아설치가간편하고가격이저렴한장점이있다. 하지만단순한구조의균형훈련제품은수동적인균형유 Table 1. Existing balance therapy products No. Product Company Illustration 1 Balance pad Thera Gear 2 Balance beam Sammons Preston 3 Shuttle Balance Training System Contemporary design 4 Balance gym Rehab tech. 5 Balance System SD BIODEX 6 Wii Sports TM Nintendo
지훈련만수행할수있는단점이있다. 또한같은동작을반복적으로수행해야하므로환자가지루함을쉽게느껴재활의지를떨어뜨릴수있으며흥미유발을위한요소가부재하다. 반면, 전력을사용하는제품 (No. 4 ~ 6, Table 1) 들은다양한훈련프로그램, 음성및시각적피드백제공하며환자정보와훈련성과를정량적으로분석할수있는환자관리소프트웨어를제공한다. 하지만높은가격 ($1,000 ~ $4,500) 으로가정용으로적합하지않다. 특히동적균형능력에필수적인상지와하지의자세를고려하지않고단순히신체의압력분포중심 (center of pressure, COP) 유지능력을결과로나타내고이를사용하여균형상태를평가하므로효과적인균형훈련을수행할수없다. 선행연구조사를통하여효과적인균형능력향상을위한운동제어요소를파악하였다. 본연구는생체역학적측면 (Lord et al, 1991), 운동제어측면 (Yavuzer et al., 2006), 감각정보측면 (Manchester et al., 1989) 에서균형유지에필요한핵심요소를분석하였다 (Table 2). 그결과, 균형은체성감각정보 (somatosensory inputs), 시각정보 (vision inputs), 그리고운동제어 (motor control) 등의복합적인작용에의하여제어됨을확인할수있었으며이는 Horak et Figure 2. Schematic diagram of physical therapy system for balance ability Table 2. System components for balance assessment System components I. Biomechanical components A. Strength B. Range of motion C. Stiffness/compliance D. Alignment II. Motor coordination components A. Maintain stability for three types of postural perturbations a. External perturbation (nudge, surface, pull) b. Anticipatory with limb movement (arm, leg, head) c. Voluntary motion of COM (lean, sway, locomotion) B. Coordinated strategies for recovery of stability a. Temporal pattern (latency, sequence) b. Spatial pattern (scaling force based on sensory) C. Strategy selection for context a. Magnitude of perturbation b. Expectation c. Initial conditions D. Adaption of postural strategy a. Immediate for change in context b. Gradual, based on prior experience c. Long term motor learning III. Sensory organization components A. Stability in altered sensory condition a. Altered vision b. Altered surface somatosensory c. Altered vision and surface somatosensory B. Limits of stability C. Perception of vertical orientation D. Motion perception E. Attention to and suppression of sensory cues Figure 3. Flowchart of physical therapy system for balance ability al. (1997) 의연구결과와유사하다. 본연구에서개발된아이디어는효과적인신체균형능력향상을위한다양한요소가포함되어있다. 신체균형능력향상을위한기능성게임물리치료시스템은 Figure 2와같은형태로개발될예정이다. 본연구를통해개발될시스템은동작분석시스템, motion platform, 압력중심측정시스템, 착용형하니스시스템, 그리고게임 contents의 5가지항목으로구분할수있다. 먼저동작분석시스템은치료대상자의움직임을검출하고화면에나타내어정확한균형과자세를유도하여훈련 의효과를높이고자한다. Motion platform은외란 (perturbation) 을발생시켜운동제어능력을높일수있으며, 외란의크기는환자의균형능력상태에따라조절될수있다. Motion platform에부착된로드셀은무게중심의이동을측정하여균형이동및균형유지정도를정량적으로확인할수있도록한다. 또한본시스템은균형능력이떨어진치료대상자의낙상방지를위하여착용형하니스시스템 (wearable harness system) 을포함한다. 기능성게임 contents는균형훈련과
SPEC(social, physical, emotional, cognitive) 측면을동시에고려한다양한게임을제공하여재활의동기를부여하고사회, 신체, 감성, 그리고인지능력을함께향상시킬수있다. 본시스템의균형훈련진행흐름도는다음 Figure 3와같다. 측정된동작분석결과와압력중심은기능성게임의입력정보로활용된다. 또한게임중균형유지능력을지속적으로평가하고평가된결과는체계적인데이터베이스로구축되어치료의효과를정량적으로나타낼수있다. 이러한결과는향후치료의방향을제시할수있는지표로활용가능하다. 본연구에서발명될신체균형능력향상을위한기능성게임물리치료시스템은기존의물리치료장비들과비교하여치료의효율측면에서우수한효과가기대된다. 개발될시스템은기존의장비에서활용하는무게중심의이동뿐만아니라신체의자세까지고려하므로더욱효과적인균형훈련을수행할수있도록유도할수있다. 또한, 적은비용으로가정에서도치료사없이손쉽고재미있게자가치료를진행할수있어지속적치료를가능토록할수있다. 따라서, 환자의자발적치료동기의고취와함께언제어디서나쉽고재미있게균형훈련을수행할수있다. 이결과환자의빠른사회활동복귀및사회적비용발생을크게감소시킬수있을것으로기대된다. 4. Discussion 본연구는효과적인균형훈련을위한기능성게임기반물리치료시스템개발을위하여 4단계절차 ( 균형훈련제품조사, 선행연구및국내외특허분석, 균형훈련시스템설계요소추출, 균형훈련시스템아이디어개발 ) 를통해제품 concept를제안하였다. 개발된균형훈련물리치료시스템아이디어는추후사용성, 만족도, 임상적활용성, 치료효과측면에서보다효과적인균형훈련방법을제공할것으로기대된다. 또한기존의물리치료장비들과비교하여치료의효율측면에서우수한효과가기대되며가정에서도치료사없이손쉽고재미있게자가치료를진행할수있어지속적치료가가능하므로경제적, 사회적파급효과가클것으로예상된다. Acknowledgements The present research was supported by Chonbuk National University Hospital References 김이영 (2006). 정신장애인의재활동기와재활성과에관한연구, 한국심리학회지임상, 25(3), 623-637. Brumels, K.A., Basius, T., Cortright, T., Oumedian, D., and Brent, S., Comparison of Efficacy between Traditional and Video Game Based Balance Programs. Clinical Kinesiology, 62(4), 26-31, 2008. Deutsch, J.E., Borbely, M., Filler, J., Karen, H., and Guarrera-Bowlby P., Use of a low-cost, commercially available gaming console (Wii) for rehabilitation of an adolescent with cerebral palsy. Physical Therapy, 88(10), 1196-1207, 2008. Gil-Gómez, J.A., Lloréns, R., Alcañiz, M., and Colomer, C., Effectiveness of a wii balance board-based system (ebavir) for balance rehabilitation: A pilot randomized clinical trial in patients with acquired brain injury. Journal of Neuroengineering and Rehabilitation, 8, 30, 2011. Holmes, A., and Delahunt, E., Treatment of common deficits associated with chronic ankle instability. Sports Medicine, 39(3), 207-224, 2009. Horak, F.B., Clinical assessment of balance disorders. Gait Posture, 6, 76-84, 1997. Hrysomallis, C., Balance ability and athletic performance. Sports Medicine, 41(3), 221-232, 2011. Isles, R.C., LowChoy, N.L., Steer, M., and Nitz, J.C., Normal values of balance tests in women aged 20 80. Journal of the American Geriatrics Society, 52, 1367-1372, 2002. Legter, K., Fear of falling. Physical Therapy, 82, 264-272, 2002. Lord, S.R., Clark, R.D., and Webster, I.W., Postural stability and associated physiological factors in a population of aged persons. Journal of Gerontol Medical Science, 46, M69-76, 1991. Manchester, D., Woollacott, M.H., Zederbauer-Hylton, N., and Oscar, M., Visual, vestibular and somatosensory contributions to balance control in older adult. Journal of Gerontol Medical Science, 44, M118-127, 1989. Yavuzer, G., Eser, F., Karakus, D., Karaoglan, B., and Stam H.J., The effects of balance training on gait late after stroke: a randomized controlled trial. Clinical Rehabilitation, 20(11), 960 969, 2006. Author listings Seunghoon Lee: shooonlee@postech.ac.kr Highest degree: M.S, Mechanical Engineering, Sogang University, 2013 Position title: Ph.D. candidate, Department of Industrial and Management Areas of interest: Digital human modeling & simulation, User-centered product design & development, Anthropometric and biomechanical methods for product development
Younggeun Choi: sidek@postech.ac.kr Highest degree: M.S., Department of Industrial and Management Position title: Ph.D. candidate, Department of Industrial and Management Areas of interest: Digital human modeling & simulation, User-centered product design & development, Anthropometric and biomechanical methods for product development, Universal design, Hyewon Lee: lhwon76@postech.ac.kr Highest degree: B.S, Industrial Design Engineering, Korea University of Technology and Education, 2012 Position title: M.S. candidate, Department of Industrial and Management Areas of interest: Ergonomic product design & development, Universal design Wonsup Lee: mcury@postech.ac.kr Highest degree: BS, Industrial and Media Design, Handong University Position title: PhD, Department of Industrial & Management Areas of interest: Ergonomic product design, Product shape design based on 3D scanning, 3D human modeling, Engineering design Taekho You: noelfly@postech.ac.kr Highest degree: B.S., Department of Industrial and Management Position title: M.S. candidate, Department of Industrial and Management Areas of interest: Ergonomic Product Design & Development, Digital Human Modeling & Simulation, Ergonomic User Interface System Heecheon You: hcyou@postech.ac.kr Highest degree: Ph.D., Industrial Engineering, Pennsylvania State University Position title: Associate Professor, Department of Industrial & Management Areas of interest: Ergonomic product design & development, User interface design & evaluation, Digital human modeling & simulation, Human performance & workload assessment, Work-related musculoskeletal disorders (WMSDs) prevention, Usability testing