Journal of the Korea Academia-Industrial cooperation Society Vol. 18, No. 7 pp. 476-482, 2017 https://doi.org/10.5762/kais.2017.18.7.476 ISSN 1975-4701 / eissn 2288-4688 이원휘전주비전대학교물리치료학과 Effect of seat height of chair on muscle activity of erector spinae and rectus abdominis Won-Hwee Lee Department of Physical Therapy, Jeonju Vision College 요약본연구는의자좌면높이가척추세움근과배곧은근의근활성도에어떠한영향을미치는지알아보고자실시하였다. 건강한남녀 30명을대상으로세가지높이의의자좌면에앉게하고양쪽척추세움근과배곧은근의근활성도를표면근전도장비를사용하여측정하였다. 반복측정된일요인분산분석을통해세가지높이의의자좌면에따른근활성도의차이를비교하였고유의수준 (a) 은 0.05로설정하였다. 연구결과의자좌면높이에따라양쪽배곧은근의근활성도는유의한차이를보였고양쪽척추세움근의근활성도는유의한차이가없었다. 양쪽배곧은근은낮은높이의의자좌면에서정상높이와높은높이의좌면에비해근활성도가유의하게증가하였다. 본연구결과를통해앉은자세에서의자좌면의높이는배곧은근의근활성도에영향을줄수있으며배곧은근의근활성도증가는요통과같은근골격계통증을일으킬수있으므로근골격계통증을예방하기위해바르게앉은자세와함께의자좌면높이는중요하다. Abstract This study examined the effects of the seat height of a chair on the muscle activity of the erector spinae and rectus abdominis. Thirty healthy subjects were asked to sit on chairs at three different seat heights. The muscle activities of both the erector spinae and rectus abdominis were measured by surface electromyography. The data were analyzed by repeated one way ANOVA and the muscle activity was compared according to the seat height. The alpha level was set to 0.05. The results showed that the muscle activities of the erector spinae were not significantly different among the three seat heights. The muscle activities of the rectus abdominis were significantly different among the three seat heights. Both the rectus abdominis muscle activities were significantly greater in the low seat height than the other seat heights. These results showed that the seat height of the chair affects the muscle activities of the rectus abdominis muscle, leading to musculoskeletal pain, such as low back pain. Therefore, the seat height of a chair with a correct sitting position is important for preventing musculoskeletal pain. Keywords : Chair, Electromyography, Low back pain, Seat height, Sitting position 1. 서론현대산업의발전으로공장의자동화와개인컴퓨터의생활화로현대인들은많은시간을앉은자세로보낸다 [1-3]. 앉은자세는서있는자세에비해상대적으로골 반이후방으로기울어지며허리뼈의곡선을반전시켜허리디스크에가해지는압력을증가시켜허리뼈에 3배이상의스트레스가가해지며누워있을때보다는 7배의스트레스가가해져허리뼈에부담이큰자세이다 [4, 5]. 그러므로앉은자세는허리뼈에스트레스가부가되는자세 * Corresponding Author : Won-Hwee Lee(Jeonju Vision College) Tel: +82-63-220-3932 email: whlee@jvision.ac.kr Received May 15, 2017 Accepted July 7, 2017 Revised (1st June 29, 2017, 2nd July 6, 2017) Published July 31, 2017 476
인데잘못된자세로장시간앉아있게되면허리뼈주변근육의근력및지구력약화, 체간연부조직의손상및디스크의퇴행성변화등으로요통이발생한다 [6]. 요통은일과관련된가장일반적인질환으로산업화된모든국가에서해결해야할중요한질환중하나이다 [7, 8]. 앉은자세에서일을하는사람은바른자세로앉아서일을해야요통을예방할수있다 [6]. 바르게앉은자세는선자세에비해골반이후방으로기울어지며허리뼈의전방커브가반전되어편평하게된자세이다 [4]. 머리를숙인자세나등을구부린자세로앉는자세는올바른자세에비해중력선이상대적으로더전방에위치하여허리뼈에더큰부하를제공하여요통이발생한다 [5]. 반대로허리를너무꼿꼿이세우고앉은자세도허리뼈의곡선을유지하기위해척추세움근과엉덩허리근이작용하여허리뼈에서는압박과전방전단력이나타나척추에부하를증가시켜요통이발생한다 [4, 9]. 또한한쪽으로치우쳐앉거나다리를꼰자세는허리뼈에서가쪽굽힘을일으키고이러한가쪽굽힘이허리뼈의하나또는두개의하위분절에서만국한되어일어나면허리뼈에더욱큰부하를초래하여요통을발생시키며다른하지관절에도영향을주어통증및정렬의변화를일으킬수있다 [4, 10, 11]. 그러므로앉은자세에서작업시요통을예방하려면바른자세로앉아서작업하는것이중요하다. 앉았을때요통에영향을줄수있는다른요소로는의자의형태가있다 [12, 13]. Kang 등의연구에서는의자형태에따라요통의차이가있다고보고하였으며등받이가없는스툴형의자를사용하는경우등받이가있는의자보다요통이많이생긴다고보고하였다 [12]. 등받이가있어서인체에적합한형태의의자는작업에따른사고나질환의방지, 피로방지의역할을하지만그렇지않은의자는근골격계에무리를주어신체골격의변형을초래하여요통을유발할수있다 [14]. 이렇게지금까지많은연구들이의자에앉아있는자세나의자의형태에따라요통에미치는영향들에대해알아보았다 [12, 15]. 하지만기존연구에서제시한대로바른자세와인체에적합한형태의의자에앉아있더라도의자좌면높이에의해서도허리뼈에영향을줄수있을것이다. 의자좌면높이는사용목적에따라다양한높이의의자가있으며좌면높이가조절되는의자도있고조절되지않는의자도있다 [16]. 적절한의자좌면높이는앉았을때엉덩관절의굽힘각도가 90도가되는높 이이다. 하지만의자좌면의높이가조절되지않는의자인경우일반성인평균신장보다신장이큰사람은의자에앉았을때의자좌면높이가낮아엉덩관절의굽힘각도가 90도이상이될것이고, 몸을앞으로구부리게되어허리뼈의곡선이반전되어구부러질것이다. 이와반대로평균신장보다신장이작은사람은의자에앉았을때좌면높이가높아발이지면에닿지않거나엉덩관절굽힘각도도 90도이하가되어엉덩허리근의근활성도가증가할것이다 [9]. 그러므로바르게앉은자세인엉덩관절굽힘각도가 90도이며허리뼈가편평한자세를취하고싶어도할수없는상황이되어요통에영향을줄수있을것이다. 허리를구성하는허리뼈는뼈의구조상불안정한구조이며이를보완하고안정성을유지하기위해서는체간근육들의적절한수축이필요하다 [17]. 척추의안정성에관여하는체간근육으로는뭇갈래근, 배가로근, 배속빗근의아래쪽섬유및척추세움근의심부근육등이있다. 척추의안정성보다는척추의움직임을일으키는체간근육으로는배곧은근과표층부의척추세움근이있으며배곧은근은허리뼈의굽힘을유도하고표층부의척추세움근은허리뼈의폄을유도한다. 척추의움직임을일으키는체간근육들의과도한활성화는척추를불안정하게하고요통을일으킬수있다 [8, 18-23]. 그러므로본연구에서는의자좌면높이에따라여러체간근육들중척추의움직임을유발하는표층부의척추세움근과배곧은근의근활성도를측정하여의자좌면높이가척추세움근과배곧은근에어떠한영향을미치는지알아보고이를통해의자좌면높이도요통에영향을줄수있는지알아보고자본연구를실시하였다. 2. 연구방법 2.1 연구대상자본연구는건강한 20대 30명 ( 남자 12명, 여자 18명 ) 을대상으로실시하였으며본연구의대상자는실험전에본연구의목적과방법에대해충분히설명을듣고연구의목적에동의하는연구동의서를작성하고연구에참여하였다. 연구대상자의선정기준은내과적질환이나허리통증및염좌등과같은근골격계관련질환을경험하지않고, 이로인한관절가동범위에제한이나근력 477
한국산학기술학회논문지제 18 권제 7 호, 2017 의감소등이없으며정형외과적또는기타수술의과거력, 팔다리의선천적기형이없는자로하였으며지난 6 개월동안허리통증이나허리골절, 관절염, 외상과같은정형외과적장애나통증을한번이라도경험했던대상자는연구대상자에서제외하였다. 2.2 측정장비및방법 2.2.1 경사계 (inclinometer) 경사계 (Baseline inclinometer, Fabrication Enterprises Inc, USA) 는 1 단위로측정할수있으며이경사계를이용하여의자좌면의높이를결정하기위한엉덩관절굽힘각도를측정하였다 (Figure 1). 경사계로엉덩관절굽힘각도를측정하는방법은앉은자세에서골반과척추의움직임을중립으로유지한상태에서대상자의넙다리위에경사계를위치하여측정하였다 [24]. Fig. 1. Measure the angle of hip flexion A. Inclinometer, B. Measure the angle of hip flexion using inclinometer 2.2.2 표면근전도시스템 (Surface electromyogram) 의자좌면높이에따라척추세움근과배곧은근의근활성도에미치는영향을알아보기위해표면근전도시스템은간편무선 EMG 시스템 (Wireless EMG System(100RT)) 의 AP1180을사용하였으며, 표면근전도시스템에서디지털처리된표면근전도신호의분석은 ( 주 ) 앞썬아이앤씨의간편무선 EMG 시스템 (Wireless EMG System(100RT) 을이용해처리하였다. 표면근전도신호의표본추출률 (sampling rate) 은 1,000Hz로설정하였다. 근육의근전도신호는제곱평균제곱근법 (Root Mean Square: RMS) 처리하여분석하였다. 표면전극의부착부위는피부저항을감소시키기위해털을제거하고, 가는사포로 3~4회문지른후알코올솜으로피부각질층을제거하고전극을부착하였다. 전극을부탁하는근육은양쪽척추세움근과배곧은근으로전극부착부위는 Criswell 등에의해제시된부위를참고하여최대근 수축이뚜렷이보이는힘살 (muscle belly) 에전극을부착하였다 [25]. 표면근전도신호의정규화 (normalization) 과정을위해자발적기준수축 (reference voluntary contraction: RVC) 을사용하였다. 자발적기준수축의측정자세는앞을보고팔은몸통옆에붙인채움직이지않고서있는자세로 1분동안이자세를유지하였다. 이때, 각근육의근전도신호를 3회씩반복측정하였으며 3회씩반복측정값에서각각처음 10초와마지막 10 초를제외한중간 40초동안의값을수집하여이값의평균값으로각각의의자좌면높이에서앉은자세에대한근활성도측정값을정규화 (%) 하였다. 2.2.3 의자의자는대상자가엉덩이를충분히지지할수있는가로 50cm, 세로 45cm의좌판을가진의자로등받이와팔걸이가있고바퀴로인한불안정성이결과에영향을줄수있으므로바퀴를고정할수있으며본연구의독립변수인의자좌면높이를조절하기위해좌면의높이조절이가능한의자를사용하였다. 좌면높이는대상자의신장이대상자마다다르기때문에절대적인좌면높이는대상자의신장에따라영향을줄수있으므로대상자의키를보정할수있도록대상자의엉덩관절굽힘각도를통해좌면높이를설정하였다. 의자좌면의정상높이 (normal height, NH) 는대상자가의자에앉았을때엉덩관절의굽힘각도가 90 가되는높이로하였고, 좌면의높은높이 (high height, HH) 는엉덩관절의굽힘각도가 80 가되는높이로하여의자의높이를설정하었으며좌면의낮은높이 (low height, LH) 는엉덩관절굽힘각도가 100 가되는높이로하여의자의높이를설정하였다 (Figure 2). 엉덩관절의굽힘각도는경사계를이용하여측정하였다. 2.3 실험방법본연구는먼저대상자의각근육에표면근전도전극을부착하고근육수축여부를확인한후근전도신호의정규화과정을위해자발적기준수축으로데이터를수집하였다. 각대상자는의자좌면의세가지높이에따라 1분간앉아있을때양쪽배곧은근과척추세움근의근활성도를측정하였다 [26]. 각각의좌면높이에서앉아있는시작자세는되도록골반과허리의위치를중립으로하였고의자의등받이에등을기대지않도록하였으며팔걸이에도팔을올려놓지 478
않게하고손은양무릎위에놓게하였으며엉덩관절의모음이나벌림또는회전이일어나지않도록중립을유지하고발은지면또는발판에닿은자세로하였다. 자세를유지하는동안골반이나허리의움직임은특별히통제하지않았다. 각대상자는앉은자세를각각의좌면높이에따라 1 분간유지하였으며각높이마다 3번씩측정하였고, 측정할때마다 5분간의휴식시간을주었고, 의자좌면의높이가바뀔때마다 10분간의휴식시간을주어근피로와같은영향을최소화하였다. 의자좌면높이에따른실험순서도무작위한순서로진행하여순서에따라미칠수있는영향을최소화하였다. Fig 2. Sitting position according to three different seat height A., B., C. 2.4 자료분석본연구는의자좌면높이에따라양쪽척추세움근과배곧은근의근활성도를비교하기위해반복측정된일요인분산분석 (repeated one way ANOVA) 을실시하였으며사후분석방법으로는 Bonferroni 검정을사용하였다. 통계적유의성을검증하기위한유의수준 (α) 은 0.05로하였고 SPSS 19.0 for Window 프로그램을사용하였다. Table 1. General characteristics of subjects Age(year) Height (cm) Weight (kg) a SD: standard deviation Mean ± SD a 22.3±2.4 165.8±8.2 59.7±10.2 (N=30) 3.1 의자좌면높이에따른척추세움근과배곧은근근활성도비교의자좌면높이에따라양쪽척추세움근은유의한차이가없었으나 (p>0.05) 양쪽배곧은근은유의한차이가있었다 (p<0.05)(table 2). 사후분석결과오른쪽배곧은근은좌면이낮은높이에서정상높이보다유의하게증가된근활성도를보였으며 (p=0.02), 높은높이와비교해도유의하게증가된근활성도를보였다 (p=0.03). 왼쪽배곧은근도오른쪽배곧은근과같이좌면이낮은높이에서정상높이보다유의하게증가된근활성도를보였고 (p=0.02), 높은높이와비교해도증가된근활성도를보였다 (p=0.03)(figure 3). Table 2. Comparison of muscle activities during sitting position according to three different seat heights Muscle Rectus abdominis (Right) Rectus abdominis (Left) Erector spinae (Right) Erector spinae (Left) Seat height a Mean±Standard deviation, * p<0.05 Muscle activity (%RVC) 0.79±0.27 a 0.87±0.35 0.79±0.27 0.82±0.27 0.91±0.31 0.83±0.26 1.30±0.94 1.43±1.01 1.28±0.87 1.15±0.52 1.19±0.49 1.14±0.52 F p 7.14 0.01 * 7.33 0.01 * 1.78 0.18 0.36 0.69 3. 연구결과 3.1 연구대상자의일반적특성전체대상자의연령은 20세 26세였으며, 평균연령은 22.3±2.4세였고, 신장은 155 180cm이었으며, 평균신장은 165.8±8.2cm이고, 체중은 46 75kg이며평균체중은 59.7±10.2kg 이었다. 연구대상자의남녀비율은 15명으로성별에따른연구결과의유의한차이는없었다. 모든대상자들의일반적인특성은 Table 1과같다. Fig. 3. Comparison of muscle activities during sitting position according to three different seat heights NH: normal height, LH: low height, HH: high height, RA: rectus abdominis, ES: erector spinae, *p<0.05 479
한국산학기술학회논문지제 18 권제 7 호, 2017 4. 논의본연구는의자좌면높이에따라여러체간근육들중척추의움직임을유발하는표층부의척추세움근과배곧은근의근활성도를측정하여의자좌면높이가척추세움근과배곧은근에어떠한영향을미치는지알아보았다. 연구결과의자좌면높이에따라양쪽배곧은근은유의한차이가있었고 (p<0.05), 양쪽척추세움근은유의한차이가없었다 (p>0.05). 사후분석결과양쪽배곧은근은의자좌면이낮은높이에서정상높이와높은높이보다유의하게증가된근활성도를보였다 (p<0.05). 배곧은근은두덩뼈능선과두덩결합에서기시하고수직으로복장뼈의칼돌기와갈비뼈위에정지하여허리뼈를굽힘하고골반을후방경사시키는근육으로배곧은근의단축또는뻣뻣함은허리뼈의굽힘과등뼈뒤굽음 (kyphosis) 에기여할수있으며배속빗근이나배바깥빗근보다배곧은근의활동성이우세하게되면몸통의회전을조절하는능력에문제를유발할수있다 [4, 27, 28]. 그러므로낮은높이의의자좌면에서유의하게증가된배곧은근의근활성도는정상높이와높은높이의의자좌면에서보다배곧은근의수축을유발하고이로인해올바른자세로앉을때보다중력선을상대적으로더전방으로위치시켜허리에더큰부하를주고디스크탈출과같은문제를일으킬수있다 [5]. Silfies 등은만성요통군과정상군의복부근육들의근활성도를비교하였는데만성요통군에서배곧은근의근활성도가정상군보다유의하게증가되었다고보고하였다 [29]. 그러므로배곧은근의증가된근활성도는요통을일으킬수있고요통의원인중하나인추간판탈출증이있는사람들은좌면높이가낮은의자에앉으면허리뼈의굽힘이증가하여요통등의증상들이더욱심해지므로좌면높이가낮은의자는피해야할것이다. 척추세움근은표층부와심부로나누어지며본연구에서는표면근전도를사용하여표층부에근활성도를알아보았는데표층부의척추세움근은엉덩갈비근, 가장긴근, 가시근으로이루어진근육으로골반에서머리까지척추와평행하게주행하여수축하면척추를폄과골반의전방경사를일으키는근육이다 [24]. 본연구결과양쪽척추세움근은의자좌면의높이에따라유의한차이가없었다. 양쪽척추세움근이의자좌면높이에따라유의한차이가없었던이유로는첫번째로본연구에서는 각좌면높이에따라 1분동안앉은자세를유지하였고유지하는동안중간 40초구간의영역의데이터를수집하였다. 이는각의자좌면높이에앉아있는동안골반이나척추의움직임은통제하지않아각각의좌면높이에적응하기위해골반과척추의보상적인움직임이일어나유의한차이가없었다고생각된다. 두번째이유로는본연구에서의자좌면높이를각대상자마다다른신장의차이를보정하기위해엉덩관절굽힘각도를통해의자좌면높이를설정하였는데실제엉덩관절굽힘범위의 10도차이가척추세움근의근활성도에차이가날만큼충분한높이가되지않아유의한차이가없었다고생각된다. 비록척추세움근의유의한차이는없었으나낮은높이에서근활성도가다른높이보다약간높은결과를보였다. 선자세에서체간을앞쪽으로숙일때허리의굽힘과골반의후방경사가일어나면서척추세움근의근활성도가증가하는데이러한현상을굽힘- 이완현상이라고한다 [30]. 체간을앞쪽으로숙일때척추세움근은체간이앞쪽으로숙이는움직임을조절하기위해편심성으로수축하고완전히굽힘이일어나면척추세움근은비활성화된다 [30]. O Sullivan 등의연구에서는척추를곧게세워서앉은자세에서허리를앞쪽으로숙이고앉은자세로자세를취하는동안척추세움근의근활성도는증가하는대상자도있고, 감소하는대상자도있어매우다양하게나타났다고하였다 [31]. 그러므로본연구결과에서도의자높이가낮을때척추세움근의근활성도가약간증가를보인이유는척추의굽힘과골반의후방경사가일어나면서이를과도하게일어나지않게하기위해편심성으로수축한것으로생각되고대상자마다근활성도가증가하기도하고감소하기도하여유의한차이가없었다고생각된다. 본연구결과를통해좌면높이가낮은의자에 1분간앉아있어도체간근육의근활성도에영향을준다는것을알수있었다. 현재인간공학적디자인을통한의자의환경개선으로의자로인한요통과같은근골격계통증발생률을감소시키기위해많은노력이이루어지고있지만적절한의자좌면높이도근골격계통증을일으킬수있는요소로서적절한좌면높이의의자에서바른자세가유지된다면더욱효과적으로근골격계통증을예방할수있을것이다. 이연구의제한점은첫번째로연구대상자가 20대의젊은남녀로만구성되어있어결과를일반화하기어 480
렵다. 또한정상인만을대상으로연구하여요통이실제로있는사람에게적용할수가없다. 두번째로의자좌면의높이에따라척추및골반의움직임을측정하지않아실제로어떠한움직임이일어나는지확인할수없었다. 세번째로표면에있는체간근육들의근활성도만알아보고실제허리의안정성에영향을주는심부근육들의근활성도를측정하지않아좌면의높이가체간심부근육들에는어떠한영향을주는지는확인할수없었다. 그러므로추후연구로는다양한연령대를대상으로한연구나좌면높이에따라척추및골반의어떠한움직임이일어나는지, 심부근육에는어떠한영향을주는지알아보는연구가필요할것이다. 5. 결론 현대사회에서는앉아서생활하는시간이길어지면서요통이발생하는사람들도함께늘어나고있는추세이다. 본연구에서는의자좌면의높이가체간근육들중척추의움직임을유발하는배곧은근과척추세움근의근활성도에어떠한영향을미치는지알아보았다. 연구결과의자좌면높이에따라양쪽척추세움근은유의한차이가없었고 (p>0.05), 양쪽배곧은근은유의한차이를보였다 (p<0.05). 사후분석결과양쪽배곧은근은낮은높이의의자좌면에서정상높이와높은높이보다유의하게증가된근활성도를보였다 (p<0.05). 본연구결과를통해좌면높이가낮은의자에 1분간앉아있어도체간근육의근활성도에영향을준다는것을알수있었다. 그러므로적절한좌면높이의의자에서올바른자세가유지된다면더욱효과적으로요통과같은근골격계통증을예방할수있을것이고, 추후다양한연령대를대상으로좌면높이에따라척추및골반의움직임과심부근육에미치는영향에대한연구가필요할것이다. References [1] A. R. Katz, "Letter by Katz regarding article, Television viewing time and mortality: the Australian Diabetes, Obesity and Lifestyle Study (AusDiab)", Circulation, vol. 122, no. 13, pp. e471, Sep. 2010. DOI: https://doi.org/10.1161/circulationaha.110.940916 [2] M. T. Hamilton, G. N. Healy, D. W. Dunstan, T. W. Zderic, N. Owen, "Too little exercise and too much sitting: Inactivity physiology and the need for new recommendations on sedentary behavior", Current Cardiovascular Risk Reports, vol. 2, no. 4, pp. 292-298, Jul. 2008. DOI: https://doi.org/10.1007/s12170-008-0054-8 [3] J. A. Levine, S. J. Schleusner, M. D. Jensen, "Energy expenditure of nonexercise activity", The American Journal of Clinical Nutrition, vol. 72, no. 6, pp. 1451-1455, Dec. 2000. [4] S. A. Sahrmann, "Diagnosis and Treatment of Movement Impairment Syndrome", Mosby, USA, pp. 54-57, 2002. [5] H. Y. Jung, J. K. Ji, S. D. Min, "Real-time Sitting Posture Monitoring System using Pressure Sensor, The Transactions of the Korean Institute of Electrical Engineers, vol. 64, no. 6, pp. 940-947, 2015. DOI: https://doi.org/10.5370/kiee.2015.64.6.940 [6] K. P. Gill, M. J. Callaghan, "The measurement of lumbar proprioception in individuals with and without low back pain", Spine, vol. 23, no. 3, pp. 371-377, Feb. 1998. DOI: https://doi.org/10.1097/00007632-199802010-00017 [7] L. Ghamkhar, M. Emami, M. A. Mohseni-Bandpei, H. Behtash, "Application of rehabilitative ultrasound in the assessment of low back pain: A literature review", Journal of Bodywork and Movement Therapies, vol. 15, no. 4, pp. 465-477, Oct. 2011. DOI: https://doi.org/10.1016/j.jbmt.2010.07.003 [8] C. Demoulin, V. Distree, M. Tomasella, J. M. Crielaard, M. Vanderthommen, "Lumbar functional instability: a critical appraisal of the literature", Annales De Readaptation Et De Medecine Physique, vol. 50, no. 8, pp. 677-684, Nov. 2007. DOI: https://doi.org/10.1016/j.annrmp.2007.05.007 [9] N. Bogduk, J. E. Macintosh, M. J. Pearcy, "A universal model of the lumbar back muscles in the upright position", Spine, vol. 17, no. 8, pp. 897-913, Aug. 1992. DOI: https://doi.org/10.1097/00007632-199208000-00007 [10] J. H. Lee, S. Y. Park, W. G. Yoo, "Changes in craniocervical and trunk flexion angles and gluteal pressure during VDT work with continuous cross-legged sitting", Journal of Occupational Health, vol. 53, no. 5, pp. 350-355, 2011. DOI: https://doi.org/10.1539/joh.11-0050-oa [11] S. Watanabe, K. Kobara, Y. Yoshimura, H. Osaka, H. Ishida, "Influence of trunk muscle co-contraction on spinal curvature during sitting", Journal of Back and Musculoskeletal Rehabilitation, vol. 27, no. 1, pp. 55-61, 2014. DOI: https://doi.org/10.3233/bmr-130419 [12] Y. J. Kang, M. H. Lee, H. Y. Yeum, "Study on musculoskeletal pain by posture and types of used chairs", The Journal of Korean Society of Assistive Technology, vol. 6, no. 1, pp. 7-14, 2014. [13] S. J. Shin, S. H. Lee, M. Y. Jung, "The Effect of Computer Work Position and Workstation on Musculoskeletal Pain", Journal of Korean Society of Occupational Therapy, vol. 12, no. 2, pp. 83-90, 2004. [14] S. H. Yoon, S. R. Park, H. J. An, "Study on Physical Symptoms by Postures and Conditions of Used Chairs 481
한국산학기술학회논문지제 18 권제 7 호, 2017 and Desks in an Elementary School Pupils", Journal of Korean Society for Hygienic Science, vol. 4, no. 1, pp. 41-54, 1998. [15] M. S. Choi, Y. J. Chung, H. W. Jeon, "The Effect of Sitting Postures on Spinal Pelvic Curvature and Trunk Muscle Activation in Low Back Pain", Korean Research Society of Physical Therapy, vol. 16, no. 2, pp. 31-40, 2009. [16] H. G. Jeong, Y. M. Roh, H. W. Yim, C. Y. Park, C. H. Jeong, "A relationship between cumulative trauma disorder and the type of workstation and chairs in workers with repetitive motion tasks", Korean Journal of Occupation Environment Medicine, vol. 13, no. 2, pp. 152-163, 2001. [17] P. Hodges, A. K. Holm, S. Holm, L. Ekstrom, A. Cresswell, T. Hansson, A. Thorstensson, "Intervertebral stiffness of the spine is increased by evoked contraction of transversus abdominis and the diaphragm: In vivo porcine studies", Spine, vol. 28, no. 23, pp. 2594-2601, Dec. 2003. DOI: https://doi.org/10.1097/01.brs.0000096676.14323.25 [18] P. W. Hodges, A. G. Cresswell, K. Daggfeldt, A. Thorstensson, "Three dimensional preparatory trunk motion precedes asymmetrical upper limb movement", Gait & Posture, vol. 11, no. 2 pp. 92-101, Apr. 2000. DOI: https://doi.org/10.1016/s0966-6362(99)00055-7 [19] S. L. Koppenhaver, J. J. Herbert, J. M. Fritz, E. C. Parent, D. S Teyhen, J. S. Magel, "Reliability of rehabilitative ultrasound imaging of the transversus abdominis and lumbar multifidus muscles", Archives of Physical Medicine and Rehabilitation, vol. 90, no. 1, pp. 87-94, Jan. 2009. DOI: https://doi.org/10.1016/j.apmr.2008.06.022 [20] P. W. Marshall, B. A. Murphy, "Core stability exercises on and off a Swiss ball", Archives of Physical Medicine and Rehabilitation, vol. 86, no. 2, pp. 242-249, Feb. 2005. DOI: https://doi.org/10.1016/j.apmr.2004.05.004 [21] J. M. McMeeken, I. D. Beith, D. J. Newham, P. Mulligan, D. J. Critchley, "The relationship between EMG and change in thickness of transversus abdominis", Clinical Biomechanics, vol. 19, no. 4, pp. 337-342, May. 2004. [22] D. M. Urquhart, P. J. Barker, P. W. Hodges, I. H. Story, C. A. Briggs, "Regional morphology of the transversus abdominis and obliquus internus and externus abdominis muscles", Clinical Biomechanics, vol. 20, no. 3, pp. 233-241, Mar. 2004. DOI: https://doi.org/10.1016/j.clinbiomech.2004.11.007 [23] J. E. Muscolino, "Know the body: Muscle, Bone and Palpation Essentials", Mosby, Elsevier, USA, pp. 250-255, 2012. [24] S. M. Bierma-Zeinstra, A. M. Bohnen, R. Ramlal, J. Ridderikhoff, J. A. Verhaar, A. Prins, "Comparison between two devices for measuring hip joint motions", Clinical Rehabilitation, vol. 12, no. 6, pp. 497-505, Dec. 1998. DOI: https://doi.org/10.1191/026921598677459668 [25] E. Criswell, "Cram's introduction to surface electromyography second edition", Jones and Bartlett Publishers, USA, pp. 342-349, 2011. [26] Y. G. Jung. "Effects of leg crossed sitting on the trunk muscle activities during the computer work", Dissertation of Master degree, Yonsei University, 2005. [27] J. P. Callaghan, J. L. Gunning, S. M. McGill, "The relationship between lumbar spine load and muscle activity during extensor exercises", Physical Therapy, vol. 78, no. 1, pp. 8-18, Jan. 1998. DOI: https://doi.org/10.1093/ptj/78.1.8 [28] F. P. Kendall, E. K. McCreary, P. Provance, "Muscle testing and function with posture and pain", 4th ed. Baltimore, Williams & Wilkins, pp. 147-150, 2007. [29] S. P. Silfies, D. Squillante, P. Maurer, S. Westcott, A. R. Karduna, Trunk muscle recruitment patterns in specific chronic low back pain populations, Clinical Biomechanics, vol. 20, no. 5, pp. 465-473, Jun. 2005. DOI: https://doi.org/10.1016/j.clinbiomech.2005.01.007 [30] O. Shirado, T. Ito, K. Kaneda, T. E. Strax, "Flexion-relaxation phenomenon in the back muscles. A comparative study between healthy subjects and patients with chronic low back pain", American Journal of Physical Medicine & Rehabilitation, vol. 74, no. 2, pp. 139-144, Mar-Apr. 1995. [31] P. O Sullivan, W. Dankaerts, A. Burnett, D. Chen, R. Booth, C. Carlsen, A. Schultz, Evaluation of the flexion relaxation phenomenon of the trunk muscles in sitting, Spine, vol. 31, no. 17, pp. 2009-2016, Aug. 2006. DOI: https://doi.org/10.1097/01.brs.0000228845.27561.e0 이원휘 (Won-Hwee Lee) [ 정회원 ] < 관심분야 > 근골격계물리치료, 물리치료진단평가 2009 년 8 월 : 연세대학교일반대학원재활학과 ( 이학석사 ) 2012 년 2 월 : 연세대학교일반대학원재활학과 ( 이학박사 ) 2012 년 3 월 ~ 현재 : 전주비전대학교물리치료학과교수 482