functional weakness of the lower extremity due to stroke is caused not only by muscular 
 weakness , but also by decreases in muscular endurance , and stability of the joint , and loss 
 of proprioceptive sense .
clinically , proprioceptive sense is an important factor in the 
 evaluation and treatment of patients with neurologic problems ; and its weakness leads to 
 declines in postural control , protective reflex , joint movement , balance ability , and 
 gait1 .
due to weakness of dorsiflexors , mass flexor pattern , or mass extensor pattern , instead of 
 reciprocal innervations , stiffness of the ankle joint , and loss of proprioceptive sense , 
 permanent disabilities , such as foot drop , are common in stroke patients2 .
primary functions of the ankle joint are the provision of 
 balance control against postural disturbance , absorption of shock during gait , and movement 
 of the lower extremity . to provide these
, it is necessary to maintain a sufficient range of 
 motion of the ankle joint , muscular strength , and proprioceptive sense3 .
limitation of ankle dorsiflexion is a common gait problem 
 of hemiparetic stroke patients . due to abnormal increase of muscle tension in the triceps 
 surae ,
stroke patients can not actively control dorsiflexion , and the foot drop tends to 
 occur4 . a normal range of motion of the ankle joint in the standing position is essential for 
 normal gait5 .
muscle cooperation in the 
 ankle joint strategy puts the center of gravity on the ankle joint in the standing position . 

it requires a normal range 
 of motion of the ankle joint and muscular strength .
if the range of motion of the ankle 
 joint is limited , postural control provided by the ankle joint is also limited6 . compared with subjects without proprioceptive sense ,
subjects with proprioceptive sense 
 appear to show a greater increase of postural sway , and lowering of balance measure 
 scores7 , all of which have important 
 roles in gait pattern .
re - education of the ankle joint movement for control of balance is an 
 important factor in remedying gait or balance problems caused by abnormal muscular 
 contraction or proprioception deficit8 . 

therefore , this study investigated the effect of a proprioceptive exercise training program 
 for improvement on the muscular strength of the ankle joint , static balance , dynamic 
 balance , and gait of stroke patients .
, 
 patients met the following criteria : stroke onset of more than six months previously , in 
 order to minimize the effects of natural recovery ; ability to walk without use of a walking 
 aid for a minimum of 15 m ; a mini - mental state examination score greater than 24/30 ; and 
 ability to comprehend and follow simple instructions .
subjects participated in a general physical therapy program lasting 30 minutes per session , 
 two sessions per week , for a period of six weeks . in addition , all subjects practiced 
 additional ankle proprioceptive control training , consisting of 30 minutes per session , two 
 sessions per week , for a period of six weeks .
subjects ' general characteristics were : male 
 10 , female 3 ; mean  sd age 58.46  years  8.53 ; height 161.09  cm  7.28 ; weight 61.83  kg  
 10.15 ; stroke onset 53.15 months  7.28 , and modified ashworth scale ( mas ) scores of 01 
 ( n=10 ) , 1 + ( n=3 ) .
subjects performed not only a general physical therapy program but also the ankle 
 proprioceptive control training program .
the ankle proprioceptive control training program 
 consisted of a program for improvement of balance ability and gait by reinforcement of ankle 
 proprioceptive control .
the program consisted of three stages : mobility of the ankle joint 
 and muscular strength ( stage 1 ) ; weight bearing in a static standing position ( stage 2 ) ; and 
 a weight bearing and assignment training program ( stage 3)9 ( table 1 ) .
each program was 
 provided 2 times per week for 30  min each session for six weeks .
the muscular strength of the ankle joint was measured using a bte - primus ( bte technology , 
 usa , 2006 ) .
this equipment evaluates patient 's range of motion , muscular strength , 
 endurance , activities of daily living , and task performance .
we measured the patients ' ankle 
 dorsiflexion and plantar flexion in the sitting position with placement of the foot on a 
 foothold .
subjects performed the timed up and go test ( tug ) before and after six weeks of physical 
 therapy . tug has shown high intra - rater ( icc=0.99 ) and inter - rater ( icc=0.99 ) reliabilities 
 and is an evaluation of dynamic balance ability10 . the test was performed three times and the mean was used in the 
 analysis of this study .
the standard gaitrite walkway has six sensor pads encapsulated in a rolled - up carpet with an 
 active area of 3.66  m length and 0.61  m width . as a subject walks along the walkway , the 
 sensors capture each footfall as a function of time and transfer the gathered information to 
 a personal computer for processing into footfall patterns .
gaitrite was used for the 
 measurement of spatiotemporal parameters , including gait velocity , cadence , step length , and 
 stride length11 . the spss 17.0 program ( spss inc . ,
the 
 shapiro - wilk test was used to test the distribution of the general characteristics and 
 outcome measures of the subjects .
repeated measures anova was used to compare pretest , 
 posttest , and retest results within groups .
at the end of the proprioceptive control training program , muscular strength of the ankle 
 dorsiflexor showed a statistically significant increases ( p<0.001 ) from 29.54 n before 
 training to 33.43 n at week 4 , and 36.84 n at week 6 .
tug , a functional balance ability test , showed significant improvements from 20.47  s before 
 training to , 17.94  s ( 4 wks ) , and 15.27  s ( 6 wks ) ( p<0.001 ) . in temporal gait ability ,
gait velocity showed significant increases from 50.35  cm / s before 
 training to , 60.45  cm / s ( 4 wks ) , and 67.55  cm / s ( 6 wks ) .
cadence showed significant 
 improvements from 76.78 steps / min before training to 81.42 steps / min ( 4 wks ) and 88.81 
 steps / min ( 6 wks ) . in spatial gait ability , step length on the paretic side significantly 
 increased from 38.88  cm before training to 44.12  cm ( 4 wks ) , and 45.16  cm ( 6 wks ) 
 ( p<0.001 ) , and significantly increased from 36.34  cm before training to 42.30  cm ( 4 wks ) , 
 and 43.79  cm ( 6 wks ) on the non - paretic side ( p<0.001 ) .
significant increases in stride 
 length from 72.84  cm before training to 86.63 cm ( 4 wks ) , and 88.92  cm ( 6 wks ) , were 
 observed on the paretic side ( p<0.001 ) , and from 75.85  cm before training to 86.70  cm ( 4 
 wks ) , and 88.90  cm ( 6 wks ) on the non - paretic side ( p<0.001 ) .
weakened muscle strength in post - stroke patients is one of the factors limiting functional 
 recovery .
as a psychological factor , in particular , patient 's self - confidence can lead to a 
 fall , due to self - limitation of activities weakened muscle strength .
balance maintenance of anteroposterior postural sway is dependent 
 on co - operative activities between the anterior tibial muscle and internal abdominal muscle . 

in other words , the activity of the internal abdominal muscle begins before the body falls 
 over a vertical line and the anterior tibial muscle activates before the body becomes 
 posturally erect13 .
andrews and bohannon2 studied the 
 recovery of stroke patients ' lower extremity muscle strengths over a short period of time . 

they reported a statistically significant improvement in ankle dorsiflexion on the paretic 
 side , from 75.6 n during hospitalization to 102.4 n after 
 intervention . in a study of lower extremity muscle torque in the movement of stroke 
 patients , kim and eng14 reported that 
 ankle dorsiflexion was weaker than ankle plantarflexion .
docherty et al.15 demonstrated there was a statistically 
 significant increase in dorsiflexor and eversion strength after an ankle joint movement 
 program lasting six weeks . in this study ,
ankle dorsiflexors showed statistically 
 significant increases on the paretic side from 29.54 n before training to , 
 33.43 n at week 4 , and 36.83 n at week 6 .
however , despite 
 the increase in ankle dorsiflexor strengths : 44.50 n ( 0 wk ) , 47.13 
 n ( 4 wks ) , and 49.39 n ( 6 wks ) , plantarflexors showed no 
 significant difference .
these results suggest that impairment of proprioceptive sense leads 
 to difficulty in maintaining balance and postural control due to loss of cognitive ability 
 of postural position in the environment16 , 17 ; however , proprioceptive sense was 
 improved by participation in the proprioceptive ankle movement program .
the increased static postural perturbation of stroke patients may be a result of balance 
 loss due to malfunction of proprioceptive sense or proper weight bearing .
the timed up and 
 go ( tug ) test , berg balance scale ( bbs ) , and functional reach test ( frt ) are standard 
 assessments of stroke patients ' dynamic balance ability . among them
, the reliability and the 
 validity of tug has been proven for the measurement of clinical changes in dynamic balance 
 ability and functional movement with time18 .
walker et al.19 
 reported that tug was 50.9 sec in the first stage of stroke and 24.9 sec after three 
 months .
in this study , after participation in an ankle proprioceptive control training program , tug 
 scores showed a significant improvements from 20.47 sec ( 0 wk ) , to 17.9 sec ( 4 wk ) , and 
 15.27 sec ( 6 wk ) . these results can be interpreted as suggesting that dynamic balance 
 ability was improved by increase of ankle sense of position through proprioceptive control , 
 and they are in agreement with the results of previous studies .
values are   mean ( sd ) . tug : timed up and go test , p : paretic side , np : 
 non - paretic side , * p<0.05 , * * p<0.01 , * * * p<0.001 improvement of gait ability during a stroke patient 's functional recovery process is the 
 main goal of both the patient and the therapist , because it is an important factor for the 
 accomplishment of functional independence20 . in a study of stroke patients ' walking patterns , edwards1 reported that cadence was 89131 steps / min 
 and stride length was 1.081.63 m. in a walking step analysis using gaitrite of 62 healthy 
 subjects , step lengths were 74.3 cm on the right side and 73.9 cm on the left side .
stride 
 lengths were 148.6 cm on the right side and 149.1 cm on the left side .
walking velocity was 
 149.5 cm / s21 . in this study , during participation in an ankle proprioceptive control program , subjects 
 gait velocities increased from , 50.35 cm / s ( 0 wk ) , to 60.45 cm / s ( 4 wk ) , and 67.55 cm / s ( 6 
 wk ) , and cadence improved from 76.78 steps / min ( 0 wk ) , to 81.42 steps / min ( 4 wk ) , and 88.81 
 steps / min ( 6 wk ) .
step length increased from 38.88 cm ( 0 wk ) , to 44.12 cm ( 4 wk ) , and 45.16 
 cm ( 6 wk ) on the paretic side , and statistically significant increases from 36.34 cm ( 0 wk ) , 
 to 42.30 cm ( 4 wk ) , and 43.79 cm ( 6 wk ) were also observed on the non - paretic side .
stride 
 length increased from 72.84 cm ( 0 wk ) , to 86.63 cm ( 4 wk ) , and 88.92 cm ( 6 wk ) on the 
 paretic side , and statistically significant increases from 75.85 cm ( 0 wk ) , to 86.70 cm ( 4 
 wk ) , and 88.90  cm ( 6 wk ) were also observed on the non - paretic side . in this study , after 
 participation in an ankle proprioceptive control program , subjects ' gait velocities 
 increased .
cadence and step length increased on the paretic side , and statistically 
 significant increases were observed on the non - paretic side as well .
stride length were 
 increased on the paretic side , and statistically significant increases were also observed on 
 the non - paretic side ( table 2 ) . in this study ,
the ankle proprioceptive control program improved the spatial - temporal 
 walking pattern of patients with stroke and the results agree with those of previous 
 studies .
we consider the ankle proprioceptive control program strengthened the ankle 
 dorsiflexors , which led to improvement in gait ability , due to prevention of foot drop in 
 the swing phase and the provision of lower extremity stability at initial contact . in 
 addition
, a more stable walking pattern might have been achieved through improvement of 
 static - dynamic balance ability leading to decreased postural perturbation .
this study 
 investigated the effect of an ankle proprioceptive control program on the recovery of 
 balance and gait abilities of hemiparetic patients stroke .
the ankle proprioceptive control 
 program focusing on somatosensory sense for the recovery of stroke patients ' balance and 
 walking abilities proved effective .
this study used an ankle proprioceptive control program 
 that consisted of three stages : mobility of the ankle joint and muscular strength ( stage 1 ) ; 
 weight bearing in a static standing position ( stage 2 ) ; weight bearing and assignment 
 training program ( stage 3 ) .
however , we did not compare the three stages to determine which 
 is the most effective for balance , gait ability , or muscle strength .
a follow - up study 
 should compare them , to determine which stages are most effective at improving patients ' 
 balance , gait ability and muscle strength .
   [ purpose ] balance and gait ability determine to a large degree the level of independence 
 of daily living which is an important goal of rehabilitation . 
 this study was conducted in 
 order to examine the effectiveness of an ankle proprioceptive control program on ankle 
 muscle strength , balance , and gait of chronic stroke patients . 
 [ methods ] thirteen chronic 
 stroke patients more than six months post - stroke were recruited . 
 all subjects received 
 ankle proprioceptive control training for 30 minutes per session , two days per week , over 
 a period of six weeks . 
 outcome measures were ankle strength ( bte - primus ) , the timed up and 
 go test ( tug ) , and spatiotemporal parameters measured by a gaitrite instrument . 
 [ results ] 
 significant improvements in ankle dorsiflexor strength , tug , gait speed and cadence , step 
 length , and stride length were observed on the paretic side . 
 [ conclusion ] the results of 
 this study provide evidence in support of incorporation of an ankle proprioceptive control 
 program for effective improvement of both balance and gait ability of chronic stroke 
 patients . 
 the findings of this study suggest the feasibility and suitability of an ankle 
 proprioceptive control program for chronic stroke patients . 
INTRODUCTION
SUBJECTS AND METHODS
RESULTS
DISCUSSION