control of the trunk of the body is a necessary condition for humans to maintain their 
 balance against gravity1 .
however , 
 patients with stroke caused by brain damage experience a diminished ability to balance 
 because of the weakened muscle strength of the trunk2 .
training to control the trunk and maintain balance is essential for 
 functional improvement in chronic stroke patients3 .
improved trunk control enhances the ability to balance , which is a 
 necessary condition for the prevention of falling .
hence , the probability of falling is 
 decreased because the ability to maintain balance is enhanced4 .
proprioceptive neuromuscular facilitation ( pnf ) improves the functions of the muscles and 
 tendons by stimulating the proprioceptive sense , which enhances muscle strength , 
 flexibility , and balance5 .
neck pattern 
 exercises are known to increase the stability of the head and neck6 .
the resistance against the neck exercise causes irradiation 
 in the body - trunk muscle exercise7 . 

however , few studies have investigated the improvement in trunk control in chronic stroke 
 patients as a result of using the pnf neck pattern .
hence , the purpose of this study was to examine the effects of the pnf neck pattern 
 exercise on the ability to control the trunk and balance in chronic stroke patients .
the subjects of this study were patients who were diagnosed with stroke through ct or mri 
 at hospital f located in daegu , korea , between january and july 2015 ( table 1table 1.general characteristics of the subjects ( meansd)experiment group ( n=15)control group ( n=15)age ( years)59.49.155.99.8after onset ( months)11.23.610.93.5gender ( m / f)5 /107 /8side ( r / l)7 /89 /6 ) .
the subjects had a duration of illness of six months or longer , a mmse - k 
 score over 24 , manual muscle testing results for neck flexion and extension graded as better 
 than fair , and the ability to sit and stand independently .
those who were incapable of 
 training , including patients with high - risk heart disease or musculoskeletal disease , were 
 excluded from the sample .
prior to the experiment , the institutional review board ( irb ) at 
 daegu fatima hospital approved the study .
this research was conducted after signed 
 agreements to participate in the study were received from the patients and their 
 guardians .
after 30 research subjects were selected , they were divided randomly and evenly into an 
 experimental group in which the pnf neck pattern was applied and a control group in which 
 traditional rehabilitation therapy was applied .
traditional rehabilitation therapy was 
 applied daily for 30 minutes to both groups five times a week for six weeks .
the 
 experimental group received additional application of the pnf neck pattern , while the 
 control group received additional application of 30 minutes more traditional rehabilitation 
 therapy per day , three times a week for six weeks .
the patients sat on 
 a mat that was knee height with their feet placed shoulder width apart and their hands on 
 their knees .
for the neck pattern , both the flexion pattern and extension pattern were 
 performed .
the experimenter 
 stood behind the patient on the right side and put the tip of his right finger below the 
 chin of the patient .
the experimenter then put his left hand slightly left of the top of the 
 patient s head in a diagonal direction .
the experimenter pulled the patient s chin so that 
 it was lifted and the neck was extended .
hence , in the preparation position , the patient s 
 head was tilted and rotated towards the right side .
the preliminary exercise was performed 
 with sufficient explanation so that the patient could accurately recognize the exercise 
 direction .
hence , the patient s head , neck , and upper 
 thoracic spine had sufficient extension , left rotation , and left lateral flexion .
the 
 experimenter provided resistance against left rotation , flexion , and lateral flexion by 
 providing traction to the patient s chin .
the identical method was applied on the opposite 
 side . for the neck extension pattern ,
he put his right thumb on the 
 right side of the patient s chin and placed his left hand slightly right of the top of the 
 patient s head in a diagonal direction .
the patient assumed the preparation position in 
 which the chin was pulled , the neck was flexed , and the head was rotated and tilted to the 
 left .
lift your head to look above .  hence , the patient s head , neck , and upper thoracic 
 spine had complete extension , right rotation , and right lateral flexion .
resistance against 
 right rotation , extension , and lateral flexion was provided during the exercise in order to 
 induce strong muscle contractions . in this study , the trunk impairment scale ( tis ) was used to evaluate the ability to control 
 the trunk .
the tis consists of 17 subitems in three categories : static sitting balance , 
 dynamic sitting balance , and coordination .
because the tis has high reliability and 
 validity , it is used to evaluate the degree of motor damage to the trunk in stroke 
 patients8 . in the tis ,
static sitting 
 balance has a minimum score of zero and a maximum score of seven , dynamic sitting balance 
 has a minimum score of zero and a maximum score of 10 , and coordination has a minimum score 
 of zero and a maximum score of 6 ; the maximum tis score is 23 .
the berg balance scale ( bbs ) , 
 which has proven reliability and validity , was used to examine the ability of patients to 
 balance before and after the exercise9 . 

the bbs consists of 14 items , each of which has a minimum score of zero and a maximum score 
 of four ; the maximum score is 56 .
the 
 nonparametric wilcoxon signed - rank test was performed to compare the tis and bbs scores 
 before and after the intervention .
statistically significant changes in all items of the tis , tis total score , and bbs were 
 observed in both the experimental group and the control group ( p<0.05 ) ( table 2table 2.comparison between before and after the interventionexperiment group ( n=15)control group ( n=15)beforeafterbeforeafterbbs41.84.247.63.342.04.344.64.3tisstatic sitting6.21.06.80.36.30.76.60.6dynamic sitting4.31.86.51.96.41.75.31.8coordination3.51.35.11.63.21.23.81.4total14.03.418.53.314.03.015.73.1*p<0.05 .
table 3table 3.comparison of effects between the groupsexperiment group ( n=15)control group ( n=15)bbs5.82.32.61.6tis static sitting0.60.90.20.4dynamic sitting2.21.40.90.8coordination1.60.70.50.5total4.41.81.71.0*p<0.05 .
bbs : berg balance scale ; tis : trunk impairment scale shows the comparison results according to the therapy method .
a significant 
 between - group difference was found in all items among the subitems of the tis except the 
 static sitting balance ( p<0.05 ) . *
selective control of the trunk affects breathing , speaking , balancing , walking , and the 
 functions of the hands and the upper limbs10 .
improvement in the ability to control the trunk is necessary to 
 enhance the ability to balance in chronic stroke patients11 .
hence , this study applied the pnf neck pattern to chronic stroke 
 patients in order to investigate the effects on their ability to control the trunk and to 
 maintain balance .
mobility and ability of the trunk to maintain balance are important factors in the 
 functional independence of stroke patients12 . moreover , improved motor control of the trunk is known to assist 
 independent performance of daily tasks in stroke patients13 .
both the experimental group and the control group showed a 
 significant difference in the bbs and tis after the intervention .
this implies that both 
 traditional rehabilitation therapy and pnf neck pattern exercises are effective in enhancing 
 the ability of chronic stroke patients to control the trunk and to maintain balance . using the tis
, park predicted falling among patients with subacute stroke , reporting that a 
 tis score between 14.5 and 15.5 corresponded to the range of risk for falling14 . in the present study
, both groups showed 
 average tis scores of 14.0 before the intervention , which was within the range of risk for 
 falling .
after the intervention , the average improved to 18.5 in the experimental group and 
 15.7 in the control group .
it is 
 possible that the pnf neck pattern exercise contributed to the ability to control the trunk 
 and maintain balance more than the traditional rehabilitation therapy did , eventually 
 decreasing the risk of falling .
moreover , park observed that better tis dynamic sitting 
 balance was connected to a lower risk of falling . in the present study ,
significant results 
 were found for all items except tis static sitting in the between - group comparison .
this 
 indicates that the pnf neck pattern exercise resulted in stronger improvement in tis dynamic 
 sitting balance , tis coordination , and bbs scores compared with the traditional 
 rehabilitation therapy .
in particular , the improvement in dynamic sitting balancing was 
 expected to contribute to the prevention of falling14 overall , the pnf neck pattern exercise was shown to have a positive effect on increasing 
 the ability to control the trunk and maintain balance in the chronic stroke patients in this 
 study . however , because of the small number of subjects , the results of the study can not be 
 generalized .
thus , in future research , studies should be conducted to apply the pnf neck 
 pattern exercise to a large sample of chronic stroke patients .
 [ purpose ] the aim of this study was to investigate the effects of proprioceptive 
 neuromuscular facilitation neck pattern exercise on the ability to control the trunk and 
 balance in chronic stroke patients . [ subjects and methods ] a total of 30 study subjects 
 were selected and randomly divided into an experimental group of 15 subjects , who received 
 the proprioceptive neuromuscular facilitation neck pattern exercise , and a control group 
 of 15 subjects , who received a traditional rehabilitation treatment . 
 [ results ] 
 statistically significant changes in all the items of the trunk impairment scale , the 
 trunk impairment scale total score , and the berg balance scale were observed in both the 
 experimental group and the control group . 
 significant between - group differences were found 
 in all items among the subitems of the trunk impairment scale except the static sitting 
 balance . 
 [ conclusion ] proprioceptive neuromuscular facilitation neck pattern exercise was 
 shown to have a positive effect on increasing the ability to control the trunk and 
 maintain balance in chronic stroke patients . 
INTRODUCTION
SUBJECTS AND METHODS
RESULTS
DISCUSSION