The Journal of Korean Society for Neurotherapy ISSN 1226-3826 http://www.jksnt.org 턱관절과넙다리뒤근고유수용성신경근촉진중재가능동입벌리기및넙다리뒤근유연성에미치는영향 윤삼원1, 손호희 *2 1부산가톨릭대학교보건과학대학물리치료학과대학원, 2 부산가톨릭대학교보건과학대학물리치료학과, The effects of proprioceptive neuromuscular facilitation(pnf) intervention for temporomandibular joints and hamstring on active mouth opening and hamstring flexibility Sam-Won Yun 1, Ho-Hee Son* 2 1Catholic University of Pusan, College of Health Sciences, Department of Physical Therapy 2Catholic University of Pusan, College of Health Sciences, Department of Physical Therapy A B S T R A C T Purpose : The purpose of this study was to investigate the effects of proprioceptive neuromuscular facilitation(pnf) intervention for temporomandibular joints and hamstring on active mouth opening and hamstring flexibility. Methods: 17 healthy adults were included in this randomized, single blind, crossover design study. the possibility of carry over effect could not be excluded. befor and after intervention, forward flexion distance, popliteal angle and active mouth opening were evaluated and results were analyzed. after first participating in the proprioceptive neuromuscular facilitation(pnf) intervention for temporomandibular joints, each subject visited again after a week to prevent the carry-over effect and then participate in the other intervention Results: Both proprioceptive neuromuscular facilitation(pnf) intervention improved significantly forward flexion distance, popliteal angle and active mouth opening. Comparing the two intervention, TM joint intervention improved significantly popliteal angle and Hamstring intervention improved significantly active mouth opening. No significant differences in forward flexion distance test were found between interventions. Conclusion: Although proprioceptive neuromuscular facilitation(pnf) intervention on Hamstring had a effect on indirect intervention of active mouth opening, it is considered that more study is needed for clinical application.
K E Y W O R D S : proprioceptive neuromuscular facilitation, active mouth opening, hamstring, direct, indirect A R T I C L E I N F O : Corresponding author : Son hohee E-mail address: sonhh@cup.ac.kr I. 서론 턱관절은지속적으로가장많이사용되는인체관절가운데하나로서씹기, 삼키기뿐만아니라말하는과정에서도사용되며하루 2,000회이상움직이며약 3.5톤의압력을치아조직에가하게된다 1). 국내에서는턱관절의장애로인하여병원을찾는평균환자수는전체인구의 0.15% 였고 3년간매년증가하는추세를보인다고하였다2). 그리고 Resche(1997) 3) 은전세계인구의약 12% 가턱관절의장애를앓고있다고보고하였다. 턱관절의장애가발생할시나타나는증상으로는아래턱의운동과관련된불쾌감, 관련근육들의통증과피로로인한씹기시장애, 턱관절운동시관절에서발생되는관절잡음그리고입벌리기의제한이있다. 이중에턱관절장애의 3대증상은턱관절의부조화, 아래턱운동시턱의통증그리고입벌리기제한이다 4). 입벌리기제한의치료로는악교정수술등의비가역적이며침습적인치료와약물요법과물리치료등의가역적이며비침습적치료방법이있다. 이중에서보존적이고가역적인치료가우선적으로시행되고있으며비가역적인치료는가급적최소로시행되고있다 5) 6). 보존적요법인약물요법중에서는진통제, 근육이완제, 삼환계항우울제등이턱관절장애의통증에효과가있다는연구가많이있으나이러한약물의유용함에도불구하고, 약물중독, 이전약들과의상충혹은부작용등과같은문제가발생할수도있다7). 그에비해물리치료요법은비침습적이며부작용도적을뿐만아니라비용도적게드는장점이있다. 입벌리기제한을치료하기위한물리치료로는물리적인자요법, 도수치료그리고고유수용성신경근촉진치료등이있다8) 9). 아래턱뼈의기능적움직임을회복하고디스크의위치를정상화시키기위하여도수치료가많이사용된다. 전위된디스크에어느정도영향을줄것인지에따라관절견인과활주움직임을연합해서적용한다. 그러나관절이불안정하고운동성이저하되어있을때에는내재성관절움직임을유발하기위한
도수치료의사용을삼가하여야한다. 과도한내재성관절움직임을유발하기위한도수치료는관절내의불안정성을증가시킬수있으므로우선고유감각과운동감각을향상시킬수있는고유수용성신경근촉진중재를점진적으로사용하는것이좋다 10). 고유수용성신경근촉진중재는신경생리학적인기전을통해관절의움직임까지크게향상될수있다고한다. 고유수용성신경근촉진중재에서주동근의수축은상호억제를거쳐길항근의이완을이끌어낸다. 그래서입벌리기동작의주동근에치료를적용하면길항근의이완이유발되어입벌리기범위가증가될수있다. 또한, 주동근의수축을 7~10초로지속할시움직임의범위가가장증가하였다는연구도있었다11). 위의물리적인자요법과도수치료그리고고유수용성신경근촉진중재는환부의직접적인적용이대부분이다. 그러나다른연구에서는환부와멀리떨어진부위에고유수용성신경근촉진중재를통해간접적인치료효과를얻을수있다고하였다. Luis(2016) 9) 는양측넙다리뒤근의고유수용성신경근촉진중재를적용시넙다리뒤근의유연성과능동입벌리기의범위가증가하였다고하였다. 환부의통증이극심하여직접적인중재를적용하기에어려움이따를경우환부가아닌떨어진부위의중재를통해원하는치료효과를얻을수있을것이다. 이처럼통증부위에직접적용하는중재가아닌원격부위의중재를통해치료효과를간접적으로얻을수있다면임상적으로많은가치가있을것이다. 비록선행연구에서넙다리뒤근과같이먼부위의고유수용성신경근촉진중재가어느정도효과가있다고하였지만턱관절에직접적으로고유수용성신경근촉진치료를적용한경우와의비교는부족한실정이라실제임상에적용하기에는어려움이남아있다. 이에본연구에서는턱관절과넙다리뒤근의고유수용성신경근촉진중재가능동입벌리기범위의변화량과넙다리뒤근유연성의변화량에미치는영향을알아보고자한다. II. 연구방법 1. 연구대상자본연구의대상자들은부산광역시에살고있는 20~30대성인남녀중에서연구의목적과방법을충분히이해하고자발적으로참여동의의사를밝힌 17명을대상으로하였다. 대상자는연구자의지시를따르는데문제가없으며, 연구의운동을진행하기에충분한근력을가지고있으며, 운동범위내에서관절범위의제한을가지지않는이들로선정하였다. 최근 6개월간급성요통을경험한자, 과거경추의채찍질손상을경험한자, 신경정신과적문제가있는자는본연구의선정과정에서제외되었다. 본연구는부산가톨릭대학교연구윤리위원회의심의를받아진행되었다. 2. 연구설계
본연구는교차설계 (cross-over trial) 연구방법을사용하였다. 초기평가후대상자들은두가지 중재방법에무작위로배치하였으며각중재에참여한다음이월효과를막기위해 1 주일이지난후 재방문하여두번째중재에참여하였다 11). 3. 측정방법모든대상자들은각중재의전과후에앞으로숙이기검사, 오금각검사그리고능동입벌리기검사를실시하였다. 1) 앞으로숙이기검사 (forward flexion distance test) 대상자는넙다리뒤근유연성측정박스위에바른자세로선다. 무릎관절은곧게편상태를유지하면서상체를앞으로최대한숙인다. 손가락을쫙편상태로두팔을최대한내린후지면과가운데손가락과의거리를 3회측정하여평균값을측정치로하였다. 2) 오금각검사 (popliteal angle test) 대상자는바로누운자세를취한다. 검사측하지의엉덩관절과무릎관절을 90도로위치시킨다. 이자세에서넙다리뼈의가쪽융기에각도기의축을일치시키고대상자에게무릎관절을최대한펴도록지시한후오금각을 3회측정하여평균값을측정치로하였다. 이때, 골반의움직임과엉덩관절의움직임이일어나지않도록한다. 3) 능동입벌리기검사 (active mouth opening) 대상자는목뼈를중립자세로위치시킨후바로누운자세를취한다. 무릎을살짝굽히고두팔은몸통옆에가지런히놓은자세에서통증이없는최대범위의능동입벌리기시윗니와아랫니의정중열사이의간격으로하여그거리를 1mm 민감도를가지고있는눈금자를이용하여최대입벌리기범위를 3회측정하였고, 그평균값을측정치로하였다. 4. 중재방법 1) 턱관절고유수용성신경근촉진중재치료사는대상자의아래턱에손바닥을촉지한후입벌리기에대하여등척성저항을 8초간가한다. 대상자들은치료사손의저항에대항하여 8초간등척성입벌리기운동을실시한다.
그리고나서대상자는근수축이일어나지않게눈을감고턱관절을 8초간이완시킨다13). 8초간등척성입벌리기운동과 8초간이완을 1세트로하여 3세트를총 48초정도간실시하였다 (8초수축 + 8초이완 + 8초수축 + 8초이완 + 8초수축 + 8초이완 ). Figure 1. Proprioceptive neuromuscular facilitation for temporomandibular joint 2) 넙다리뒤근고유수용성신경근촉진중재대상자는침대위에바로누운자세를취하고중재반대측하지에골반과허벅지부위를스트랩 (strap) 으로고정시킨다. 무릎을폄 (extension) 상태에서대상자의넙다리뒤근이신장될때통증을최대로참을수있는범위까지수동으로엉덩관절을굽힘시킨다 14)feitas. 이상태에서넙다리뒤근이수축할수있게무릎을굽히면서엉덩관절을 8초간폄시키며이때, 치료사는저항을가한다 15). 수축이완료되면처음자세로돌아와서 8초동안근수축이일어나지않게눈을감고이완한다. 8초간수축운동과 8초간이완을 1세트로하여 3세트를총 48초정도간실시하였다 (8초수축 + 8초이완 + 8초수축 + 8초이완 + 8초수축 + 8초이완 ). Figure 2. Proprioceptive neuromuscular facilitation for hamstring muscle 5. 분석방법본연구의자료는 SPSS 21.0 ver for windows를이용하여통계처리를하였고유의수준 (a) 은 0.05로설정하였다. 각중재전과후에따른능동입벌리기범위와넙다리뒤근유연성의변화량을알아보기위해대응표본 t검정 (paired t-test) 을실시하였으며, 두중재별변화량을비교하기위해독립표본 t검정 (independent t-test) 을실시하였다.
III. 결과 1. 대상자의일반적특성 본연구에참여한대상자는총 17 명 ( 남자 10 명, 여자 7 명 ) 의성인남녀이며, 평균연령은 22.35 세이며, 평균 키는 170.11cm, 평균몸무게는 64.52 이었다 <Table 1>. Table 1. Demographic characteristics of the subjects(n=17) Variable Total Gender(male/female) 10/7 Age(year) 22.35 Height(cm) 170.11 Weigh(kg) 64.52 Mean±standard deviation; *,p<.05; 2. 턱관절고유수용성신경근촉진중재 턱관절고유수용성신경근촉진중재시앞으로숙이기검사, 오금각검사그리고능동입벌리기검사에서 모두통계적으로유의한차이가있었다 (p<0.05)<table 2>. Table 2. Comparisons of forward flexion distance, popliteal angle, active mouth opening in TMJ group variables Pre Post T p Forward flexion distance test(cm) 2.69 0.35 6.97 0.00 Popliteal angle test( ) 65.82 68.05-4.88 0.00 Active mouth opening(cm) 4.39 4.73-9.11 0.00 Mean±standard deviation; *,p<.05; 3. 넙다리뒤근고유수용성신경근촉진중재 넙다리뒤근고유수용성신경근촉진중재시앞으로숙이기검사, 오금각검사그리고능동입벌리기 검사에서모두통계적으로유의한차이가있었다 (p<0.05)< 표 3>. Table 3. Comparisons of forward flexion distance, popliteal angle, active mouth opening in Hamstring group variables Pre Post F p Forward flexion distance test(cm) 2.47-0.35 8.14 0.00 Popliteal angle test( ) 65.47 70.82-6.15 0.00 Active mouth opening(cm) 4.42 4.6-3.46 0.001
Mean±standard deviation; *,p<.05; 4. 그룹간각검사의변화량비교 그룹간각검사의변화량을비교한결과앞으로숙이기검사에서는유의한차이가없었 고오금각검사와능동입벌리기검사에서는유의한차이가있었다 <Table 4>. Table 4. Comparison of pre-post changes between groups variables TI HI T p Forward flexion distance test(cm) 2.34 2.83-1.02 0.31 Popliteal angle test( ) 2.23 5.35 3.17 0.003 Active mouth opening(c`m) 0.34 0.14-3.88 0.00 Mean±standard deviation; *,p<.05 tempromandibular joint intervention, TI; Hamstring intervention, HI Ⅳ. 고찰 본연구는턱관절고유수용성신경근촉진중재와넙다리뒤근고유수용성신경근촉진중재후능동입벌리기와앞으로숙이기그리고오금각범위에미치는영향을비교하고자 17명의건강한 20대성인남녀에게교차설계 (cross-over trial) 방법을이용하여연구하였다. 턱관절의고유수용성신경근촉진중재와넙다리뒤근고유수용성신경근촉진중재를적용한결과앞으로숙이기검사와오금각검사그리고능동입벌리기검사에서두군모두유의하게증가하였다. 각그룹간변화량의비교에서앞으로숙이기검사에서는두군간의유의한차이는없었고오금각검사와능동입벌리기검사에서는턱관절에직접중재를적용한그룹의변화량이유의하게크게나타났다. 본연구에서는고유수용성신경근촉진중재에서유지후이완 (Hold-Relax) 기법을적용하였다. 그이유로는많은넙다리뒤근신장기법중에서도유지후이완기법을사용한넙다리뒤근고유수용성신경근촉진중재가가장흔하게사용되고있으며뿐만아니라관련된연구도많이이루어져왔기때문이다 9)16)17). Youdas 등 (2010) 17) 은넙다리뒤근고유수용성신경근촉진중재가어떤넙다리뒤근신장기법보다더효과적이라고하였는데그이유는골지힘줄기관과근방추를통해이뤄지는신경생리학적인기전으로인해관절가동범위가증가되기때문이라고하였다. 위의신경생리학적인기전은전통적으로골지힘줄기관의장력수용기를거치는자가억제기전과근방추를거치는상호억제기전을포함한다. 넙다리뒤근의힘줄에위치하는골지힘줄기관의장력수용기가유지후이이완기법과정에서첫번째로활성화되는데이는자가억제기전을통한넙다리뒤근의억제를유발한다. 뿐만아니라 Lim 등 (2014) 15) 은고유수용성신경근촉진중재는근수축을유발하는반사활동을감소시키기위해신장전에자발적인 근수축을시행하여근이완을유발한다고하였으며이러한이유로 Espejo 등 (2016) 9) 의연구에서능동 입벌리기의간접적인치료로넙다리뒤근고유수용성신경근촉진중재를적용하였다.
턱관절의직접적인중재에해당하는턱관절고유수용성신경근촉진중재를적용한후앞으로숙이기검사와오금각검사그리고능동입벌리기범위에서유의하게증가하였다. 이는깨물근의근막통증유발점에의해야기된턱관절장애의치료인초음파치료와고유수용성신경근촉진중재효과에대해비교한 Gray 등 (2002) 18) 의연구에서턱관절에 5분간초음파치료를받은군에서는능동입벌리기에서유의한차이가없었으나, 턱관절에고유수용성신경근촉진중재를받은군에서는능동입벌리기에서유의하게증가한양상을보였다는결과와일치하는경향을보였다. 턱관절의간접적인중재에해당하는넙다리뒤근고유수용성신경근촉진중재의적용후앞으로숙이기검사와오금각검사그리고능동입벌리기범위가유의하게증가하였고이는턱관절장애가있는운동선수에게넙다리뒤근신장혹은깨물근의허혈성압박마사지와넙다리뒤근신장을결합하여중재하였을시넙다리뒤근유연성과능동입벌리기그리고통증의즉각적인변화를알아본 Espejo 등 (2016) 9) 의연구에서깨물근의허혈성압박마사지와넙다리뒤근신장을결합한대조군뿐만아니라넙다리뒤근신장만을적용한실험군모두에서능동입벌리기가유의하게증가하였다는결과와일치하는경향을보였다. 이처럼원격부위의중재를적용하여턱관절에간접적인효과를알아보는연구는꾸준히있어왔다. 깨물근의통증유발점이있다고진단받은성인남녀에게넙다리뒤근신장기법적용후즉각적인효과에대하여알아본 Cesar 등 (2005) 19) 의연구에서넙다리뒤근근에너지기법을적용하였을시깨물근의통증이줄어들며능동입벌리기가증가한다고하였고, 건강한성인남, 녀에게넙다리뒤근신장기법적용후즉각적인효과에대하여알아본 Christina 등 (2009) 20) 의연구에서는양쪽넙다리뒤근혹은우세발의넙다리뒤근에정적신장을적용하였을시위등세모근과깨물근에서통증이감소하였고능동입벌리기가증가하였다는연구내용으로미루어보아고유수용성신경근촉진중재를통한넙다리뒤근의신장과능동입벌리기상호간에밀접한관계가있음을알수있었다. 그러나턱관절과넙다리뒤근고유수용성신경근촉진중재후각각의넙다리뒤근유연성과능동입벌리기변화량을비교한결과앞으로숙이기검사에서는두중재군모두효과는있었지만서로간의유의한차이가없었고, 오금각검사에서는두중재군모두효과는있었지만직접적인중재에해당하는넙다리뒤근고유수용성신경근촉진중재군이더유의하게증가하였다. 능동입벌리기검사에서도두중재군모두효과는있었지만직접적인중재에해당하는턱관절고유수용성신경근촉진중재군이더유의하게증가하였다. 능동입벌리기검사를보면직접적인중재에해당하는턱관절고유수용성신경근촉진중재에서유의하게증가하였는데턱관절의좌상-역좌상기법과신경근테크닉에따른능동입벌리기의변화에관하여연구한 Jordi 등 (2008) 21) 에따르면각각능동입벌리기가 0.4cm만큼유의하게증가하였고, 턱관절고유수용성신경근촉진중재를적용한 Gray 등 (2002) 17) 의연구에서는 2번째방문에서능동입벌리기가 0.28cm증가하였고, 4번째방문에서는 0.66cm까지증가하였다. 이에반해건강한성인을대상으로넙다리뒤근신장기법을적용한 Christina 등 (2009) 20) 의연구에서는우세쪽넙다리뒤근신장기법적용후
능동입벌리기가 0.08cm 증가하였고, Espejo 등 (2016) 9) 의연구에서는넙다리뒤근고유수용성신경근촉진중재적용후 0.34cm 증가하였다. 본연구결과에서도넙다리뒤근고유수용성신경근촉진중재시능동입벌리기가 0.14cm 증가하였는데반해턱관절고유수용성신경근촉진중재시 0.34cm 증가한것으로나타나넙다리뒤근의고유수용성신경근촉진중재를포함한간접적인신장중재에비해직접적인턱관절중재그룹에서능동입벌리기증가량이크게나타났다. 본연구의결과를통해턱관절과넙다리뒤근고유수용성신경근촉진중재가능동입벌리기와넙다리뒤근유연성에간접적인영향을미치는것을알수있었다. 그이유는아마도턱관절과위경추그리고넙다리뒤근간의밀접한관계가있기때문인것으로사료된다. Natalia 등 (2010) 22) 의연구에따르면위경추와턱관절상호간생체역학적인관련성이있다고하였고, Drew 등 (2003) 23) 은위경추의등척성수축후이완시경막이신장되어넙다리뒤근과같은다른부위에원격치료의효과를이끌어낼수있다고하였다. 뿐만아니라조성학등 (2014) 24) 은뒤통수밑근의이완으로인해표면후방선이이완되어넙다리뒤근유연성에영향을미칠수도있다하였고, 뒤통수밑근은머리자세의조정에상당히기여하며, 인체에서가장많은근방추를가지고있는고유수용성감각감지기라고하였다. Pollard 등 (1997) 25) 은경추는하지와상지의기능과자세조절에중요한역할을한다고하였다. 그들은뒤통수밑근에고유수용성신경근촉진중재를적용시그결과로활성화된고유수용성감각정보가자세긴장도 (posture tone) 를바꿀수있다고하였다. 자세긴장도를포함한경추부의고유수용성감각정보는대뇌겉질과위둔덕, 전정핵, 그물체그리고소뇌겉질을거쳐전정척수로, 그물척수로그리고대뇌척수로를통해하지까지도달한다는연구내용으로미루어보아턱관절과넙다리뒤근상호간에긍정적인영향을미친것으로사료된다. 앞서언급한 Espejo 등 (2016) 9) 이제시한넙다리뒤근의고유수용성신경근촉진중재는비록턱관절의통증이경감되며능동입벌리기가증가된다는등의연구가일부있어왔으나턱관절부위의직접적인치료와의비교를통한간접적인치료의효과정도에대한연구는미비한실정이라임상적용을위한근거가부족하였다. 이와같은간접적인치료의효과는턱관절의통증이극심하거나염증, 종양그리고부종등으로인해직접적인치료의어려움이있을경우유용하다는점에서그의의가있기때문에본연구는능동입벌리기에대한넙다리뒤근고유수용성신경근촉진중재의임상적용을위한근거를제시하기위하여능동입벌리기의직접적인중재에해당하는턱관절고유수용성신경근촉진중재와간접적인중재에해당하는넙다리뒤근고유수용성신경근촉진중재를비교하는연구를시행하였다. 비록직접적인중재에해당하는턱관절고유수용성신경근촉진중재의효과가더크게나타났으나간접적인중재에해당하는넙다리뒤근고유수용성신경근촉진중재도유의한효과가있음을알수있었다. 이러한결과를토대로아직까지는넙다리뒤근고유수용성신경근촉진중재를능동입벌리기의중재로임상에서적용하기에는더많은연구가필요하지만다른부위의중재를통해간접적인치료효과를얻을수있다는점에그의의가있다고사료된다.
본연구의대상자들은모두건강한성인들로구성되어있어서연구결과를환자들을대상으로하는임상에바로일반화시키기에는어려움이있을것이다. 그리고턱관절과넙다리뒤근고유수용성신경근촉진중재의즉각적인효과만을보았기에앞으로의연구에서는더많은피험자를대상으로혹은턱관절장애나특정질환을가진환자들을대상으로장기적인중재효과를증명할수있는연구가필요할것으로사료된다. 또한본연구에서는한다리만의고유수용성신경근촉진중재를적용하였지만앞으로두다리의고유수용성신경근촉진중재를다룬연구들이필요하다고사료된다. Christina 등 (2009) 20) 의연구에서는양쪽의넙다리뒤근고유수용성신경근촉진중재시우세쪽의넙다리뒤근고유수용성신경근촉진중재보다능동입벌리기가 1.75배증가하였다. 이처럼양쪽의넙다리뒤근고유수용성신경근촉진중재가능동입벌리기에직접적인중재만큼의효과가있다면큰의의가있을것으로보이며향후이와관련된연구들이필요할것으로생각된다. Ⅴ. 결론 본연구는겅강한성인남녀 17명을대상으로턱관절고유수용성신경근촉진중재와넙다리뒤근고유수용성신경근촉진중재시앞으로숙이기, 오금각그리고능동입벌리기에미치는영향을알아보았다. 연구결과턱관절고유수용성신경근촉진중재시앞으로숙이기, 오금각그리고능동입벌리기검사에서유의한변화가있었고, 넙다리뒤근고유수용성신경근촉진중재에서도앞으로숙이기, 오금각그리고능동입벌리기검사에서유의한변화가있었다. 두중재를비교한결과앞으로숙이기검사에서는서로간의유의한차이는없었다. 오금각검사에서는넙다리뒤근고유수용성신경근촉진중재군이더유의하게증가하였고, 능동입벌리기검사에서는턱관절고유수용성신경근촉진중재군이더유의하게증가하였다. 이러한결과를토대로비록능동입벌리기에있어서간접적인중재에해당하는넙다리뒤근고유수용성신경근촉진중재가직접적인중재에해당하는턱관절고유수용성신경근촉진중재만큼의효과는아니지만다른부위의중재를통해서간접적인치료효과를얻을수있다는점에그의의가있다고사료된다. References 1. Kim JS, Kim DE, Jung DH, et al. A Review of Recent Studies for Treatment of TMD Using CNKI Database. Journal of Korean Medicine Rehabilitation. 2016;26(2):61-74. 2. Cho MS, Kim CS, Cheon SH. Association between self-esteem and temporomandibular disorder in the high school students. Journal of Korean society of Dental Hygiene. 2016;16(1):111-120. 3. LeResche L. Epidemiology of Temporomandibular Disorders: Implications for the Investigation of Etiologic Factors. Critical Reviews in Oral Biology & Medicine. 1997;8(3):291-305.
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