JKPT pissn Vol. 27, No. 4, August 2015 1229-0475 eissn 2287-156X Original Article http://dx.doi.org/10.18857/jkpt.2015.27.4.246 Effects of Closed Chain Exercise on Activities of Shoulder Girdle Muscles in 60 s Hye Jin Park 1, Tae Young Oh 2 1 Department of Physical Therapy, Rehabilitation Center, Seoho Hospital; 2 Department of Physical Therapy, Silla University, Busan, Korea Purpose: The purpose of this study was to compare activities of shoulder girdle muscles according to types of closed chain exercise in the sixties. Methods: The subjects consisted of 15 persons in their sixties. Muscle activity of the pectoralis major, deltoid middle, deltoid posterior, upper trapezius, lower trapezius, and serratus anterior were measured using electromyography according to shape of the support base and angle of shoulder flexion. According to types of closed chain exercises, muscles activities were compared by paired t-test. Significance level to verify statistical significance was.05. SPSS win (ver. 22.0) program was used for statistical analysis. Results: Muscle activities of the pectoralis major, middle deltoid, trapezius lower, and serratus anterior showed significant difference according to types of closed chain exercise (p<0.05). Conclusion: According to types of closed chain exercises of the shoulder girdle, muscle activities of the pectoralis major, deltoid middle, posterior and lower trapezius showed change of muscle activities. Keywords: Closed chain exercise, Muscle activities, Shoulder girdle muscle 서론관절와상완관절 (glenohumeral joint) 은구상관절로서인체의모든관절중활동범위가가장크고복잡한부위라고하였다. 1 견관절의정상적인기능과안정성은일상생활에서중요하며, 이것은견관절복합체를구성하는여러관절들의상호작용과균형에의존한다고하였다. 2,3 관절와상완관절은견관절복합체에서일어나는운동의중심이며, 어깨의지지, 안정성을유지하기위하여뼈나인대보다근육에의존하고있다고하였다. 4 견관절움직임의중심적역할을하는견갑골은견관절복합체와관련된근육의길이-장력관계를가장효과적이게하며, 5 관절와상완관절을안정화시키기위해상완골의움직임과함께협력해작용한다고하였다. 6 승모근, 견갑하근, 능형근, 소원근, 전거근등은견관절을위해일정하면서도효율적인길이장력관계를유지시켜줌으로써견관절의안정성에기여한다고하였다. 7 견관절은인대와근육의힘만으로팔의다양한운동과상지의무게를지지하고팔운동의조절과안정을제공하여손의많은기능을수행하게하는관절이며, 견관절주위의근육, 결합조직, 피부등의 운동성과유연성과함께관절가동성을정상적으로유지하는것이매우필요하다고사료된다. 노화는상 하지의근력감소와관련되며, 8 이는관절가동범위와근육의유연성이동시에감소하게된다고하였다. 9,10 Barnes 등 11 은연령이증가함에따라견관절의내회전을제외한전방거상, 신전, 외전, 90도외전에서의내회전, 외회전과내전상태에서의외회전에서견관절의가동범위가감소함을보고하였다. 연령이증가함에따라 65세이상의건강한노인의 30% 정도가견관절의장애를가지고있는것으로보고하고있으며, 12,13 60대이상인구에서 60% 까지나타난다고하였다. 14 또한노화는관절의결합조직이뼈의선운동이나회전운동을방해하며, 이는관절의가동범위를제한하기도하고, 근육의능동근력과관절의안정성을제한하기도한다고하였다. 14 최근노인들의체력즉근, 신경, 신체구성등에관한연구가활발하게이루어지고있으나상지보다는하지에관한연구들이많이이루어져온것이사실이다. 이는하지의근력이나기능이균형과낙상에깊이관련이있는것으로사료되나, 상지의기능또한매우중요하다. 상지는머리를빗거나지퍼를올리는것, 옷을머리위로입을때와 Received Jul 23, 2015 Revised Aug 20, 2015 Accepted Aug 21, 2015 Corresponding author Tae Young Oh E-mail ohtaeyoung@silla.ac.kr Copylight 2015 The Korea Society of Physical Therapy This is an Open Access article distribute under the terms of the Creative Commons Attribution Non-commercial License (Http:// creativecommons.org/license/by-nc/3.0.) which permits unrestricted non-commercial use, distribution,and reproduction in any medium, provided the original work is properly cited. 246 www.kptjournal.org
Closed Chain Exercise for Shoulder Girdle Muscles JKPT 등뒤로손을뻗는등의기능적동작을수행하는데필요하며, 노인들의삶의질을평가하는데매우중요한요소가된다. 15 관절의안정성을증진시키는운동에는열린사슬운동과닫힌사슬운동이있는데, 열린사슬운동은관절가동범위가제한된환자의근력강화를위해중요한역할을한다고하였다. 16 닫힌사슬운동은사지의원위부는고정되어있는상태에서근위부와원위부에서저항을동시에적용할때일어나는운동으로, 17 근력강화, 지구력증진뿐만아니라관절면의기계적인압박을통해여러근육의협응수축을일으키며, 관절부위의고유수용성감각을제공하므로관절의동적안정성과자세유지를위해운동치료프로그램에서자주이용하고있다고하였다. 18,38 견갑골안정화를위한닫힌사슬운동에는푸쉬업 (push up exercise), 푸쉬업플러스 (push up plus exercise), 월푸쉬업플러스 (wall push up exercise), 등척성볼운동 (isometric ball exercise) 등이있으며, 19-21 닫힌사슬운동이부하없는열린사슬운동보다통증이있거나불안정한견관절재활프로그램에생체역학적으로안전하고기능적이라고하였다. 22 Weon 등 23 은전방머리자세를중립머리자세와비교하여앉은자세로등척성상완굴곡을각 30, 60, 90, 120 에서실시하였을때전거근, 승모근상부, 하부섬유의근활성도를연구하였다. Hardwick 등 24 은벽슬라이드운동 (wall slide exercise) 을실시하였을때벽을마주하고선자세에서견관절의굴곡 90, 120, 140 각도에서전완을벽에붙인상태로슬라이드운동을실시한후전거근의활성도를다른운동과비교하였다. 견관절안정화를위한열린사슬, 닫힌사슬운동형태에서의근활성도비교, 상완굴곡각도에따른근활성도를비교한연구는있었으나닫힌사슬운동에서지지면의변화와함께상완굴곡각도에따른견관절주위근들의근활성도를비교하는연구가주로 20대를대상으로이루어졌으며, 60세이상의노인을대상으로하는연구는매우부족하였다. 이에본연구에서는정상노인들에게견관절의안정성에작용하는근육들을닫힌사슬운동을통하여알아보고자하였으며, 닫힌사슬운동의형태에따라근활성도가어떻게변화되는지확인하고자견관절굴곡각도와지지면에변화를주어노인들의견관절주위근활성도에미치는영향을알아보고자하였다. 연구방법 1. 연구대상본연구는연구목적과방법에대하여충분한설명을들은후자발적으로본실험에참여할것을서면동의한건강한 60대 15명 ( 남자 : 8 명, 여자 : 7명 ) 으로구성되었으며, 평균 59.7세, 평균신장 165.7 cm, 평균체중 64.93 kg이며, 어깨근육의위축, 기형정형외과적혹은신경학적증상을호소하는자는제외하였으며정기적으로어깨관련근력운동을하는자도제외하였다. 2. 실험방법 1) 근전도본연구에서는표면근전도 (surface EMG, KEYPOINT R, Medtronic, USA) 를사용하였다. 근전도신호의표본추출률 (Sampling rate) 은 1,024 Hz로설정하였고, 근전도의주파수대역폭 (bandwidth) 은 20-450 Hz를사용하였다. 실험전견갑골안정화에기여하는대흉근, 중앙삼각근, 후면삼각근, 상부승모근, 하부승모근, 전거근을대상으로하였으며, 2 근전도신호량측정을위해 Boettcher 25, Gawk 26 등의연구를참조하여각근육의전극부착위치를결정하였다. 근전도신호에대한피부저항을줄이기위해, 측정부위의털을제거하여알코올솜으로부착부위를깨끗하게하였다. 전극은표면근전도측정을위한도자를이용하였다. 근전도전극부착후각근육의신호를점검한후본실험을실시하였다. 실험을통해얻어진각근육의근활성도를표준화하기위해서도수근력검사자세에서최대등척성수축 (Maximal voluntary isometric contraction, MVIC) 시각근육의근활성도를측정하였다. 5초동안의자료값을 root mean square (RMS) 로수집한후중간 3초간의 RMS값을 %MVIC로사용하였다. MVIC 측정자세는 Kelly, 27 McCabe 28 등의연구를참고하였다. 2) 압력생체되먹임장치본실험에사용된압력생체되먹임장치는 pressure biofeedback unit (Stabilizer, Chattanooga Group Inc., Hixson, USA) 으로안정화근육들의재교육을위해물리치료사들에의해개발된치료도구이다. 치료를하는동안압력센서는환자들에게유용한시각되먹임정보를제공해준다. 경추와요추안정화근육들의재교육과각관절들의안정성증진을위해자주사용되어진다고하였다. 29 3. 실험절차실험전대상자들에게실험에대해충분히설명한후진행하였다. 닫힌사슬운동을이용한실험을위해실험대상자는벽을마주하고선자세에서실험하였다. 닫힌사슬운동에서견관절굴곡각도와지지면변화에따른견관절주위근활성도를보기위하여견관절굴곡각도는 90 와 135 로구분하여진행하였고, 지지면은종이와압력생체되먹임장치 (Stabilizer) 로구분하여진행하였다 (Figure 1). 모든대상자 www.kptjournal.org 247
JKPT The Journal of Korean Physical Therapy Hye Jin Park, et al. A B C D Figure 1. (A) Shoulder 90 flexion on paper. (B) Shoulder 135 flexion on paper. (C) Shoulder 90 flexion on stabilizer. (D) Shoulder 135 flexion on stabilizer. 들은무작위순서로운동을실시하였다. 각각의조건을 3회씩측정하였으며, 조건간 1분의휴식을주었다. 근전도신호는견관절을 90 와 135 굴곡을유지한상태에서 5초간최대한힘을주어벽을밀면서지지면을유지하도록하여획득하였으며, 실험절차는다음과같았다. 1) 대상자들은무작위순서로각각의지지면에서왼쪽상완을각각 90 와 135 굴곡하였다. 2) 종이를이용하여닫힌사슬운동을할때에는대상자에게종이가떨어지지않게유지하도록하여실험을진행하였다. 3) 압력생체되먹임장치를이용하여닫힌사슬운동을할때에는초기압력을 20 mmhg로설정한후, 대상자에게압력값을 40 mmhg 로유지하도록하여실험을진행하였다. 4. 분석방법바로선자세에서견관절굴곡각도와지지면에따른따른견관절주위근의활성도를비교하기위하여대응표본 t-검정 (paired t-test) 를실시하였다. 이연구에서통계학적유의성을검정하기위해유의수준 α = 0.05로정하였다. 자료의통계처리는 SPSS (Win ver. 22.0) 프로그램을이용하였다. 결과 1. 견관절굴곡각도와지지면에따른대흉근의활성도비교대흉근의근활성도를분석한결과, 상완 135 굴곡상태에서지지면변화에는근활성도에유의한차이가있었으며 (p < 0.05), 종이지지면에서상완굴곡각도변화에따라근활성도에유의한차이가있었다 (p< 0.05) (Table 1). 2. 견관절굴곡각도와지지면에따른중앙삼각근의활성도비교중앙삼각근은상완 90, 135 굴곡상태에서지지면변화에따라근활성도에유의한차이가있었다 (p < 0.05) (Table 1). 3. 견관절굴곡각도와지지면에따른하부승모근의활성도비교하부승모근은압력생체되먹임장치지지면에서상완굴곡상태에따라유의한차이가나타났다 (p < 0.05) (Table 1). 4. 견관절굴곡각도와지지면에따른전거근의활성도비교전거근은상완 90 굴곡상태에서지지면변화에따라근활성도에유의한차이가있었다 (p < 0.05) (Table 1). 고찰본연구에서는 60세이상노인들을대상으로닫힌사슬운동형태와견관절의굴곡각도를변화시켜견관절주위의활성화되는근육의변화를확인하고자하였다. Davies 등 34 의견관절복합체의신경근재활에관한연구에서, 닫힌사슬자세에서의견관절강화운동은관절낭의부하를줄여주고역동적인안정화구조의동시수축을촉진시킨다고하였다. Khademi Kalantari 35 의연구에서는 20대대상자에게지지면의변화에따라상부및하부승모근, 전거근, 이두근장두, 후면삼각근, 대원근의활성도를근전도로측정한결과엎드린자세에서워블보드 (wobble board) 와스위스볼 (swiss ball) 작은공등을이용한불안정한지지면의닫힌사슬운동이안정된지지면의닫힌사슬운동과비교하였을때근활성도를증가시키지못한다고하였다. 본연구에서는 60대대상자에게바로선자세에서견관절 90 굴곡상태로압력생체되먹임장치를지지하였을때대흉근, 중앙삼각근에서근활성도가의미있게증가하였다. 상부승모근은견관절굴곡각도와상관없이압력생체되먹임장치보다종이를지지하였을때근활성도가의미있게증가한것을볼수있었다. 이는 Khademi Kalantari의연구에서실시한엎드린자세는견관절 90 굴곡상태에서체중지지를하는상태로볼수있으며, 본연구에서는선자세에서견관절 90 굴곡상태에서불안정한압력생체되먹 248 www.kptjournal.org
Closed Chain Exercise for Shoulder Girdle Muscles JKPT Table 1. Comparison of muscle activities of each muscles according angle and surface (Unit: %MVIC) Muscle Angle Paper Stabilizer t p Pectoralis major Shoulder 90 35.73± 19.55 a 43.23± 24.19-1.203 0.249 Shoulder 135 27.33±17.95 42.49±22.28-4.452 0.001 t 2.477 0.109 p 0.027 0.915 Deltoid middle Shoulder 90 25.55± 11.19 a 55.27± 20.19-6.732 0.000 Shoulder 135 25.51±10.64 63.50±19.77-8.536 0.000 t 0.049-1.961 p 0.962 0.070 Deltoid posterior Shoulder 90 16.72± 20.43 a 15.84± 11.15 0.251 0.805 Shoulder 135 17.30±17.41 13.77±14.49 0.749 0.466 t -0.399 0.574 p 0.696 0.575 Trapezius upper Shoulder 90 27.53± 15.55 a 24.38± 16.80 0.865 0.402 Shoulder 135 25.94±14.65 21.16±17.30 0.948 0.359 t 0.978 0.743 p 0.345 0.470 Trapezius lower Shoulder 90 28.03± 21.35 a 27.25± 17.26 0.136 0.894 Shoulder 135 25.11±15.46 17.42±11.43 2.143 0.050 t 0.999 2.273 p 0.335 0.039 Serratus anterior Shoulder 90 56.35± 26.10 a 37.10± 21.61 2.123 0.052 Shoulder 135 47.62±19.37 37.29±22.90 1.266 0.226 t 3.204-0.037 p 0.006 0.971 a Mean±SD. 임장치를지지하였을때대흉근, 중앙삼각근에서활성도가높았다는결과와서로상반된결과를보이고있으며, 이에반해상부승모근은견관절각도와상관없이벽에위치한안정된종이를선자세에서밀때높은활성도를나타낸것은일부일치하는결과라고할수있을것이다. 대흉근의쇄골부분은쇄골의흉골쪽에서기시하여상완골의대결절능에부착되어견관절을굴곡시키고수평내전시킨다. 흉늑골부분은흉골의전면, 6-7번째늑골, 연골그리고외복사근건막에서기시하여상완골의대결절능으로부착되어견갑골을하강시킨다고하였다. 30 삼각근은쇄골의외측, 견봉, 견갑극에서기시하여상완골삼각근조면에정지하는근육으로서, 견관절메커니즘의가장큰생리학적단면적근육이며, 상완관절의외전에서가장중요한역할을한다고하였다. 30 외전을하는동안중앙삼각근은가장활성화된다. 전면삼각근은상완의굴곡에영향을미치며, 후면삼각근은신전에영향을미친다. 상완골의축회전과함께결합된측면회전을통해서후면삼각근의모멘트팔은더작아진다. 후면삼각근은전방굴곡 90 이상이되면큰모멘트팔이되며, 활성화된다. 증가하는후면삼각근의활동 으로인해중앙삼각근은전방굴곡 60 에서가장크게활성화된다고하였다. 5 Lehman 등 21 은 10명의젊은남성을대상으로한연구에서안정한지지면과불안정한지지면에서푸쉬업 (push up) 과푸쉬업플러스 (push up plus) 운동을한후상부승모근, 하부승모근, 전거근, 상완이두근등의모든근육에서지지면안정에따른근활성도는통계적으로유의한차이가없었으나, 지지면안정도와관계없이손과발의위치변화에서는상부승모근과전거근의활성도가유의한차이가있었다고보고하였다. 본연구에서는벽에위치한종이를밀때를안정된지지면, 생체압력되먹임장치를불안정한지지면으로볼때, 견관절을 90 로굴곡과불안정한면에서의닫힌사슬운동이대흉근과중앙삼각근의근활성도를높였던것으로나타나일부일치하는면이있으며, 상부승모근의근활성도가지지면에상관없이견관절각도에따라유의하게높게나타나역시일부일치하는면이있는것으로사료된다. 이는견관절안정성에관여하는근육들중지지면의안정성에따라서는근활성도의차이가크게나타나지않지만, 견관절의굴곡각도의변화에따라서는근활성도의차이가크게나타난다는것을의 www.kptjournal.org 249
JKPT The Journal of Korean Physical Therapy Hye Jin Park, et al. 미하고있으며, 이는건강한 20대와건강한 60대의결과가전혀상반되지않는것으로사료된다. Moon 36 의연구에서건강한성인남성 16명 ( 평균연령 20.7세 ) 을대상으로열린사슬운동과닫힌사슬운동에서상완굴곡각도에따른상부승모근, 대흉근, 전거근등의활성도를견관절 70, 90, 110 에서측정한결과상부승모근, 대흉근의근활성도는견관절굴곡각도와운동형태에따라유의한차이가없었으나, 전거근의근활성도는굴곡각도의변화에따라유의한차이가있었다고보고하였다. Moon 36 의연구는선자세에서닫힌사슬운동을위하여벽에기계식저울을밀도록하였으며열린사슬운동을위해서는뒤쪽벽에있는밴드를앞으로팔을뻗으면서내밀도록하여본연구에서이용한방법과는다소다른방법을선택하였다. 본연구에서는상완을종이에지지하여굴곡각도가증가함에따라대흉근, 전거근의근활성도는유의한차이를나타냈다. 압력생체되먹임장치에지지하여굴곡각도가증가함에따라하부승모근의근활성도는유의한차이를나타냈으며, 중앙삼각근과전거근의근활성도가통계적으로유의하지는않았지만증가하는것을볼수있었다. Moon 36 연구결과에서전거근의결과는견관절굴곡각도에따라변화를보여준본연구와일부일치하는면을보이고있으며, 상부승모근의결과는서로다른양상을보이는것으로나타났다. 승모근의일반적인기능은상부승모근의견갑골상방회전과거상, 중간승모근의후인, 하부승모근의상방회전과하강을포함한다. 또한하부승모근의내측하부방향의섬유들은팔을굴곡시키는동안에견갑골의외회전과후방경사에기여한다. 31 상부승모근의높은활성도와관련된활동은숄더쉬러그 (shoulder shrug), 엎드린자세에서팔끌어올리기 (prone rowing), 엎드린자세에서내 외회전이동반된외전에서 90 와 135 수평외전이다. 하부승모근의높은활성도와관련된활동은엎드린자세에서팔끌어올리기 (prone rowing), 엎드린자세에서내 외회전이동반된외전에서 90 와 135 수평외전, 90 외전에서외회전이다. 하부승모근의활성도는 90 이하에서의 scaption, 외전, 굴곡에서점차적으로낮아지는경향이있으며, 90 에서 180 까지기하급수적으로증가한다고하였다. 32 전거근은소흉근과함께견갑골을외전시키며, 상 하부승모근과함께견갑골을상방회전시킨다. 전거근은상지를굴곡시키는동안에상방회전, 후방경사, 외회전같은정상적인견갑골움직임의모든요소에기여하는중요한근육이다. 또한견갑골의내회전과전방경사를막기위하여견갑골의내측면과하각을안정화시키는데도움을준다고하였다. 31,33 Jang 37 의연구에서는 20대 15명의남자를대상으로열린사슬운동과닫힌사슬운동을하는동안상완을 0, 45, 90, 135 로굴곡한상 태에서외회전을하여극하근, 전면삼각근, 중앙삼각근, 후면삼각근, 상부승모근, 원회내근의근활성도를비교한결과전면삼각근, 중앙 삼각근, 상부승모근, 원회내근은운동방법과상완굴곡각도의변화 에따라유의한차이가나타났으나, 후면삼각근은운동방법과상완 굴곡각도의변화에따른유의한차이가나타나지않았다고보고하 였다. 본연구의결과와비교하였을때운동방법과견관절굴곡각도에 따라일부일치하는결과를나타내었다. Kim 등 39 은뇌졸중환자 30 명을대상으로압력생체되먹임장치 를이용한어깨안정화운동이대상자들의견갑골거리, 동적균형등 에서유의한개선을보였다고하여뇌졸중환자들의견갑대안정화 를위해안정화운동, 즉닫힌사슬운동이필요할것으로사료된다. 결론적으로본연구는 60 대의닫힌사슬운동형태가견관절주위 근활성도에미치는영향에대해알아보았으며, 대흉근, 중앙삼각근, 하부승모근, 전거근은지지면의변화보다는견관절따라더큰근활 성도의차이가있었다고할수있다. 따라서본연구를통하여젊은대상자가아닌 60 대이상의노인들 에게견관절주위근의안정화를위하여견관절굴곡각도, 지지면상 태등을변화시킴으로써다양한근활성도의변화를확인할수있었 으며, 이는견관절안정화운동, 편마비환자의견관절안정성향상 등을위해임상적으로널리이용될수있는기전을확인한결과로서 그의미가크다고할수있을것이다. 또한선행연구가거의 20 대대상 자를연구한결과이므로향후같은실험방법을통하여 20 대와 60 대 의견관절안정성에관여하는근육들의활성도를비교하는연구가 필요할것으로사료된다. 본연구의제한점은일반인을대상으로실험을하였으므로다양 한환자에게일반화하기에는무리가있을것으로사료되며, 노화에 따른근활성도의차이를임상적으로해결할수있는다양한관리가 이루어져야할것으로사료된다. REFERENCES 1. Curl LA, Warren RF. Glenohumeral joint stability. Selective cutting studies on the static capsular restraints. Clin Orthop Relat Res. 1996;330:54-65. 2. Decker MJ, Hintermeister RA, Faber KJ et al. Serratus anterior muscle activity during selected rehabilitation exercise. Am J Sports Med. 1999;27(6):784-91. 3. Hess SA. Functional stability of the glenohumeral joint. Man Ther. 2000; 5(2):63-71. 4. James AP, Carl D. Mechanical shoulder disorder: Perspectives in functional anatomy. Philadelphia, Elsevier Saunders. 2004;91-125. 5. Van del Helm FC. Analysis of the kinematics and dynamic behavior of the shoulder mechanism. J Biomech. 1994;27(5):527-50. 250 www.kptjournal.org
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