E ffe ct of P o s te rior Le af S pring on S t anding B alanc e in P atie nt s W ith H em iple g ia

In t r o d u c t i o n

Balan ce can be explained either st at e or function . Balance as a st at e is defined as a body in the equilibrium or zer o sum of for ce (Johan sson and Magnu s son , 1991).

Balance as a function is defin ed as a function that continuou s mu scle activity and j oint motion ar e r equir ed t o m aint ain the cent er of m ass within the base of support (Iv er son et al, 1990). Balance is affect ed by som at osen sory dy sfunction ,

E ffe c t o f P o s t e rior Le af S prin g o n S t an din g B alan c e in P at ie nt s W ith H e m iple g i a

K im J o n g - m a n , P h .D., P .T . Dept . of Phy sical T her apy , S eonam Univ er sity

Y i Ch u n g - h w i, P h .D., P .T .

Dept . of Reh abilitation T her apy , College of Health S cience In stitut e of Health S cience, Yon sei Univ er sity

Y a n g H oi - so n g , M.Sc., P .T .

Dept . of Phy sical T her apy , S am sun g Medical Cent er Cy n n H e o n - se o ck , M.A ., R .P .T .

Dept . of Phy sical T h er apy , Han seo Univ er sity

국 문 요 약

P L S 착 용 이 편 마 비 환 자 의 동 적 균 형 에 미 치 는 영 향

김종만

서남대학교 물리치료학과 이충휘

연세대학교 보건과학대학 재활학과 및 보건과학연구소 양회송

삼성서울병원 물리치료실 신헌석

한서대학교 물리치료학과

이 연구는 성인 편마비 환자를 대상으로 PLS (Posterior Leaf Spring) 착용이 기립 균 형에 미치는 영향을 알아보는 것이었다. 신발만 착용하였을 때의 기립조건과 신발과 PLS 를 동시에 착용한 기립조건의 평균평형지수가 맨발로 서 있을 때의 기립조건에 비하여 높았다. 그러나 신발만 착용한 기립조건과 신발과 PLS를 함께 착용한 기립조건하에서의 평균평형지수의 차이는 없었다. 따라서 편마비 환자의 기립균형과 관련하여 PLS만을 착 용한 효과와 신발만을 착용한 효과를 비교하는 연구가 필요하다.

핵심단어 : 균형; 편마비 환자; Post erior Leaf Sprin g.

visual field deficit , mu scle w eakness, joint contr acture, spasticity, and abnormal postur e.

F unction al limit ation and fall occur s as an affect ed balan ce (S aladin , 1996). Phy sical ther apist should ev aluate and tr eat these fact or s that can affect balance.

Hemiplegic patient s from stroke, tr aum atic brain injury , and cer ebral palsy dem on str at e pr oblem s such a s asymm etrical postur e, abnormal postur al contr ol, asymmetrical w eight bearin g , sitting or st anding dy s - function s, disability t o r est or e a balance when balance is lost , disability to m aint ain balance when performin g a functional t ask (Carr and Shepher d, 1980; Lee et al, 1988;

Saladin , 1996). Decr em ent of v olunt ary sw ay while standin g , in appr opriat e mu scle selection t o pr oduce corr ect r eaction , decr em ent of r eaction for ce in hemipar etic side, incr ea sed lat en cy to postur al r eaction in hemiparetic side cause balance dy scontr ol in patient s with br ain dam age (Dettm ann et al, 1987).

Resear ches on balance of patient s with brain damage have been carried out r ecently with an influen ce of sy stem s theory that v ariou s sy st em s inv olv e t o achiev e a function al t ask s. Hor ak (1991) suggest ed that balance is affect ed by an int er action of musculoskeletal system, motor coor dination , per ception to dir ection , sensory or ganization , predictive central set, environmental adapt ation , perception, and motivation. Therefore, phy sical ther apist should det ermine the cau se of balance dy scontr ol an d solv e the pr oblem s t o impr ov e balance function .

Orthotic devices h av e been applied t o enhance balance function and gait perfor - m ance of hemipar etic patient s (Br an dst at er

et al., 1987; Diam ond an d Ott enbacher , 1990; Lehm ann , 1983). T wit chell (1951) suggested that ankle j oint deformity fr om spasticity an d contr actur e not only pr ev ent w eight bearin g but also r educe dur ation of w eight bearing int o hemiplegic low er extr emity . Kim an d Yi (1997) indicat ed that w earing ankle- foot - orthoses (AF O) w ould impr ov e balan ce. Lee and Kw on (1997) r eport ed that ankle r an ge of motion influenced equilibrium after the stu dy of equilibrium perform an ce ability of normal adolescent . T hese finding s sugg est ed that abnormal ankle joint dysfunction of hemiplegic per son s can delay r ecov ery pr ocess in r ehabilit ation period.

Ankle- foot - orthoses support , pr ot ect , and corr ect ankle j oint (Light an d Kam en et s , 1966). Sarno and Lehn eis (1971) pr escribed AF O for the patient s w ith un st able knee, m oder ate spasticity in low er ex tr emity , and no v olunt ary ankle joint mov em ent s.

Diamond an d Ott enbacher (1990) pr escribed dynamic AF O t o impr ov e alignm ent of ankle and foot and t o incr ease w eight distribution for effectiv e w eight tr an sfer .

It is ex pect ed fr om the fin ding s of pr eviou s studies that h emiplegic per son s w earing PLS will impr ov e balan ce an d ambulation capability by corr ecting j oint deformity fr om contr actur e an d spa sticity and enhancing w eight bearin g . T hough previous studies were performed to inv estigat e the effect of PLS on g ait char act eristics of hemiplegic per son s (Cor cor an et al, 1970;

Diamond an d Ott enbacher , 1990; Kim et al,

1996; Lehm ann et al, 1987), studies that

inv estigat e the effect of PLS on balance

w as not perform ed y et . T he purpose of

this r esear ch , ther efor e, w as to a ssess the st anding balan ce perform an ce of hemiplegic per son w earin g PLS by a comput erized dynamic postur ogr aphy device.

M e t h o d s

S ubje c t s

Subj ect s con sist ed of 15 patient s who were receiving phy sical therapy as inpatient s or out patient s at S eoul S am sung Medical Cent er affiliated w ith Sungkyunkw an Univ er sity Medical S chool (T able 1).

Inclu sion crit eria for subject s ar e as follow s : 1) hemiplegic patient s who w er e diagnosed w ith cer ebr ov ascular accident , tr aum atic br ain injury , or cer ebr al palsy , 2) hemiplegic patient s who w er e pr escribed t o w ear a PLS by a m edical doctor , 3)

hemiplegic patient who can un der st an d and follow investigators instructions, 4) hemiplegic patient s wh o w er e able t o st an d for 10 minut es w ith out as sist ance, 5) hemiplegic patient s without orthopedic diseases in lower extr emities, and 6) hemiplegic patient s who agr eed t o participated on th e study . Medical char acteristics of subj ect s w er e pr esent ed (T able 2).

In s trum e nt s an d pro c e dure s

EquiT est 5.02 ¹⁾ con sist ed of safety belt for patient s st ability , for ce plate (23 ㎝ × 46 ㎝), visual surr oun ding , m onit or which w as place par allel with visual surr oundin g , and soft w ar e (EquiT est Pr ogr am and Sen sory Or ganization T est ). T w o for ce

1. N euroCom Int ernation al Inc. USA

T able 1 . General char act eristics of t he subj ect s (N =15)

Char act eristics Mean±SD Fr equen cy

S ex Male

F em ale

10 5

Age (yr s ) 53.8±13.8

Body Wt . (㎏) 60.9±6.3

T able 2 . Medical char act eristics of t he subj ect s (N =15)

Char act eristics Mean±SD F r equ ency

Diagn osis

Hem orrh age 10

Infar ction 5

P ar aplegic side

Right 8

Left 7

Elapsed tim e fr om on set (w eek ) 153.5±513.2

plat es w er e positioned t og eth er so that subject can st an d along the longitudinal line dr aw n at each for ce plat e. T w o pr essur e sen sor s w er e embedded anterior - post erioly at each for ce plat e. Subj ect s w er e a sked t o stand without chan ging feet position with upper extr emities r elax ed.

A ssessm ent w as performed in six con dition s : (1) eyes - open condition ; (2) eyes - closed condition ; (3) ey es - open , fix ed for ce plat e, and sw aying visual surr ound pr oportional t o subject s ant erior - post erior sw ay ; (4) eyes - open and sw ayin g surr ound pr oportional t o subject s ant erior - post erior sw ay ; (5) eye- closed and m ovin g surr ound pr oportional t o subject s ant erior - post erior sw ay ; and (6) ey es - open an d for ce plate and visual surr ound sw aying pr oportional to subject s ant erior - posterior sway . A sses s - m ent w as perform ed for 20 seconds thr ee times w ith 10 seconds of r estin g period per each condition . T he equilibrium scor e w as determined by each condition and ex pr essed as a per cent age fr om 0% t o 100%, 100%

equilibrium scor e in dicated subj ect s m ain - t aining balance without any sw ay , and 0%

equilibrium scor e in dicated a subject s falling because of in st ability . T he composit e equilibrium scor e w as calculat ed by m ean of six equilibrium scor es.

E x pe rim ent pro c e dure s

1) T h e w eight bearing distribution in st anding w as m easur ed u sin g EquiT est pr ogr am in bar e- foot st anding , standin g in shoes , and st anding in shoes with PLS con dition s. A subj ect w as not allow ed t o hav e any visu al input fr om comput er m onit or by placing comput er m onitor aw ay

fr om a subject s visual field. A subject w as asked t o st an d on for ce plat e in r elax ed position . T he body w eight of a subject w as m easur ed. T h e m easur em ent or der w as r an domly select ed by a subj ect t o contr ol the or der effect .

2) T he balance in standing was m easur ed u sing EquiT est sen sory or ganization t est (S OT ) pr ogr am in bar e- foot standin g , st anding in shoes, and st anding in shoes with PLS condition s.

D at a an aly s i s

Kolm ogor ov - Smirnov t est w as u sed t o det ermine th at collect ed data w er e n orm ally distribut ed. Repeat ed m easur es ANOVA w as u sed t o compar e composit e equilibrium scor es of thr ee condition s : bar e- foot st anding , standin g in shoes, and st anding in shoes with PLS . Bonferr oni corr ection t est w as u sed a s a multiple comparison t est . SAS w as u sed an d significance lev el w as 0.05.

R e s u l t s

Kolm ogor ov - Smirnov test in dicat ed th at collect ed dat a w er e n orm ally distributed.

Composite equilibrium scor es were calculat ed (T able 3).

T able 3 . Av erage equilibrium in dex by st andin g condition s (Unit : %)

Condition s Mean±SD

Bar efoot 65.20±9.22

With shoe 68.40±7.44

With shoe and PLS

68.73±8.85

*

PLS : Post erior Leaf Spring

T her e w as a st atistically significant difference among composite equilibrium scor es (T able 4).

Bonferr oni corr ection t est in dicated that composit e equilibrium scor es of st anding - in - shoes condition w er e high er than those in bar e- foot - st anding con dition ; composit e equilibrium scor e of st an din g - in - shoes with PLS condition w as higher th an th ose of bar e- foot st an ding con dition . T her e w a s no significant differ en ce bet w een composit e equilibrium scor es of standin g - in - shoes con dition and scor es of st anding - in - shoes with PLS condition .

D i s c u s s i o n

PLS has been pr escribed to impr ov e st anding balan ce and ambulation in clinical setting s. How ev er , ther e ar e disadv ant ages of w earing PLS as an orthotic device such as decr ea sed adapt ability and not pr oviding functional recovery at ankle joint mu sculatur e by limiting j oint m ov em ent . T her e ar e only a few studies that show ed the effect of PLS . T his r esear ch w as perform ed t o inv estigat e the effect of PLS on st anding balance of hemiplegic per son s.

Balan ce can be classified int o static balance and dyn amic balan ce. St atic balance r efer s t o th e ability t o st an d without perturbation on st abilized base, an d dynamic balance r efer s t o the ability t o m aint ain equilibrium with ext ernal pertur -

bation or with self - g ener at ed m ov ement . T her efor e, balance as sessm ent t ool can be classified int o st atic, dyn amic, or functional balance as sessm ent t ool (Ragnar sdottir , 1996).

T he r ole of orthosis is t o pr ovide the affect ed low er extr emity with equal w eight bearing and t o affect st anding balance positively by compensating for lost function , supporting and pr ot ecting the joint , and producing normal movement with st abilization (Lehm ann et al, 1983; P erry , 1974). Condie and Condie (1995) adv ocat ed that PLS w as u sed to impr ov e balan ce and pr oprioceptiv e feedback by encour aging w eight bearing on low er extr emity . T hey also indicat ed th at the u se of PLS w ould pr ev ent joint contr actur e and inhibit primitiv e r eflex patt ern s.

Kim et al (1997) studied the effect of PLS on low er ex tr emity w eight bearin g in patient s with h emiplegia an d r eport ed that w eight bearing on affect ed extr emity without PLS (42.7%) w a s m or e than that with PLS (40.1%). It w as suggest ed w hen the PLS w as applied, decr eased som at o- sen sory feedback fr om plantar surface and pr oprioceptiv e feedback fr om mu scles and joint ar oun d ankle influ enced negativ ely on st anding balance. How ev er , it w as contr o- v er sial that 1.6% differ ence in w eight bearing is m eaningful clinically . In pr esent study , composit e equilibrium scor es of st anding - in - shoes con dition w er e higher T able 4 . Repeat ed one- w ay ANOVA result s by st an ding condit ions

Sum of S qar es DF Mean S quar e F p

Condition 114.2 2 57.1 4.4 .02

Err or 364.5 28 13.0

than those in bar e- foot - st anding condition . How ev er , composite equilibrium scor es of st anding - in - shoes with PLS condition w as not higher than those of st anding - in - shoes con dition . T h er e w a s a possibility that the effect of PLS w as ov er shadow ed by w earing sh oes in st anding - in - shoes w ith PLS condition. T her e was another possibility that ankle str at egy can not be efficiently u sed when PLS w as applied t o ankle j oint ; this possibility can n ot be t estified in pr esent study becau se st an din g balance w as not m easur ed with PLS condition .

F utur e study is r equir ed to inv estigat e the effect of PLS by comparin g standin g with PLS only condition and st anding - in - shoes condition . How ev er , gait tr aining in standin g - in - shoes with PLS condition is m or e appr opriat e than that in st anding with PLS only condition in clinical setting . T her efor e, it is suggest ed that balance in st anding - in - shoes with PLS condition pr ovides clinician s with critical and m eaningful inform ation . Under the Kor ean cu st om s, shoes ar e u sually t aken off indoor s. Furth er r esear ch is needed t o benefit h emiplegic patient w hen they ar e w earing PLS without shoes indoor s.

F in ding s of this study should be gener alized cautiou sly becau se only the patient s gr oup who satisfied the inclu sion crit eria at Sam sung Medical Cent er partici- pat ed in the study . It cannot be conclu ded that applying PLS impr ov es the st anding balance in patient s with hemiplegia becau se st anding balance w a s n ot mea sur ed with PLS con dition . How ev er , it is con cluded that in st anding - in - shoes with PLS con dition impr ov ed st anding balance in

patient s with hemiplegia.

C o n c l u s i o n

T he purpose of this r esear ch w as to inv estigat e the imm ediate effect of PLS on the st anding balance in hemiplegic patient s.

T he r esult s in dicat ed that composit e equilibrium scor es of standin g - in - shoes con dition an d st anding - in - shoes with PLS con dition w er e higher than that in bar e- foot - standing condition . However , there w as no significant differ ence betw een composit e equilibrium scor e of st an din g - in - shoes con dition an d st anding - in - shoes with PLS con dition . F utur e study is needed t o compar e st an ding with PLS only condition and st anding - in - shoes con dition in r elation t o st anding balance in patient s with hemiplegia.

R e f e r e n c e s

Br andst at er ME, Bruin H , Gowlan d C, et al. Hemiplegic gait : Analy sis of t empor al v ariables. Ar ch Phy s Med Rehabil. 1987;64:583- 587.

Carr JH , Sheph er d RB. Phy sioth er apy in Disor der s of the Br ain . Lon don , Heinem ann , 1980.

Con die E , Con die D. Orthotic m an agem ent of str oke patient s. In : Harrison MA , ed. Phy sioth er apy in Str oke Man age- m ent , Chur chill Living stone, 1995.

Cor cor an PJ , Jeb sen RH , Br en gelm ann GL, et al. Effect s of plastic and met al leg br aces on speed an d ener gy cost of hemipar etic ambulation . Ar ch Phy s Med Rehabil. 1970;51:69- 77.

Dettm ann MA , Linder MT , S epic SB.

Relation ships am on g w alking perfor - m ance, postur al st ability , and fun ction - al assessment s of the hemiplegic patient . Am J Phy s Med Reh abil.

1987;66:77- 90.

Diamond MF , Ottenbacher KJ . Effect of a tone- inhibiting dynamic ankle- foot orth o- sis on stride char act eristics of an adult with hemipar esis. Phy s T her . 1990;70:

423- 430.

Hor ack F B. A ssumption s un derlying m ot or contr ol for n eur ological r ehabilit ation . In : List er MJ , ed. Cont empor ary Man - agem ent of Mot or Contr ol Pr oblem s : Pr oceeding s of the Ⅱ ST EP Con - fer ence. Alex an dria, VA : APT A , 1991.

Iv er son BD, Gos sm an MR, Shaddeau SA , et al. Balance perform ance, for ce pr oduction , and activity lev els in n on - in stitutionalized men 60 t o 90 y ear s of age. Phy s T her . 1990;70:348- 355.

Johan sson R, Magnusson M. Human postur al dyn amics. Biom ed Eng . 1991;18:413- 437.

Kim JM , Lee JW , Yi CH , et al. T he r elation ship bet w een sen sory or g aniza - tion an d balance in patient s w ith hemiplegia. Journ al of the Kor ean Academy of Univer sity T r ained Phy sical T her apist s. 1997;4:61- 69.

Kim T H , Curr ent M , Kim JM . A study on the imm ediate effect s of w eight distribution and gait pattern s of hemiplegic patient s thr ough PLS on an d off. Journal of th e Kor ean Academy of Univer sity T r ained Phy sical T her apist s. 1996;3:55- 76.

Kim JM , Yi CH . Neur ological Phy sical T her apy . Kor ea, Chungdam Co., 1997.

Lee WA , Deming L, S ahgal V . Quantit ativ e and clinical measures of static st an ding

balan ce in h emipar etic and norm al subj ect s. Phy s T her . 1988;68:970- 976.

Lee HS , Kw on HC. T he influen ce of foot an gle on st anding balan ce upon the un st able platform . Journal of the Kor ean Academy of Univer sity T r ained Phy sical T her apist s. 1997;4:34- 44.

Lehm ann JF , Con don SM , Price R, et al.

Gait abnormalities in h emiplegia : T h eir corr ection by ankle- foot orthoses. Ar ch Phy s Med Reh abil. 1987;68:763- 771.

Lehm ann JF , E sselm an P C, Ko MJ, et al.

Plastic ankle- foot orthoses : Ev alu ation of fun ction . Ar ch Phy s Med Rehabil.

1983;64:402- 407.

Light S , Kam enet z H . Orthotics Et cet er a.

New Hav en , Elizabeth Licht , 1966.

P erry J . Kinesiology of low er extr emity br acin g . Clin Orthop. 1974;102:18- 31.

Ragnar sdottir M . T h e concept of balance.

Phy siother apy . 1996;82:368- 375.

Saladin LK. Cer ebr ov ascular disease. In : F r ederick s CM , Saladin LK , eds.

P athophy siology of the Mot or Sy stem s : Principles an d clinical pr esent ation s, Philadelphia, F A Davis Co., 1996.

Sarno JE, Lehneis HR. Pr escription con sider ation for plastic below - kn ee orthoses. Ar ch Phy s Med Rehabil.

1971;52:503- 510.

T wit ch ell T E . Rest or ation of m ot or

function followin g hemiplegia in man .

Br ain . 1951;74:443- 480.