vlaeyen et al jor 1995

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Journal o f Occupational Rehabilitation VoL 5 No. 4 1995

T h e R o l e o f F e a r o f M o v e m e n t / R e ) I n j u r y i n P a i n

Disa b i l i t y

J o h a n W . S . V l a e y e n 1 2 4 A n k M . J . K o l e -S n i j d e r s 1 A n n e m a r i e M .

R o t t e v e e l 1 R e n s k e R u e s i n k 3 a n d P e t e r H . T . G . H e u t s 3

It is now well established that in chronic low b ack pain, ther e is no direct relationship

between impairments, pain, and disability. From a cognitive-behavioral perspective,

pa in d i sab i l i t y i s no t on ly in f luen ced by the organ ic pa tho logy , bu t a l so by

cognitive-perceptual, psychophy siological, an d motoric-environm ental factors. This

pa pe r foc use s o n the role of specific beliefs that are associated w ith avoidance o f

activities. T hese beliefs are related to fea r o f m ov em en t an d physical activity, which is

wrongfully) assum ed to cause re)injury. Two studies are presented, o f which the first

examines the facto r structure o f the T am pa Scale fo r Kinesiophobia TSK), a recently

developed questionnaire that is aimed at quantifying fear of movement/ re)injury. In

the sec ond study, the value o f fea r o f movement/ re)injury in predicting disability levels

is analyzed, w hen the biomedical status o f the patien t an d current pa in intensity levels

are controlled for. In addition, the determinants o f fea r o f movement/ re)injury are

examined. The discussion focu ses o n the clinical relevance o f the fear-avoidance m od el

in relation to r isk assessment, assessme nt o f fun ctio na l capacity, a nd secondary

prevention.

KE Y W OR DS : chronic low back pa in; fear-avoidance; fear of move men t ; fear of re )injury; fear of pain;

kines ioph obia; behavioral as ses sment

INTRODUC~ON

Many people suffer from low back pain in the course of their lives, of which

not

a l l

seek health care. In the majority of the patients who seek care and refrain

from work, the pain problem resides within a few weeks. Data presented by the

Quebec Task Force on Spinal Disorders (1) show that 74 of the group of patients

1Ins t i tu te for Rehabi l i tat ion

Resea rch , Zandbe rgsweg 111 , 6432 CC Hoensbroek , The Ne t he r l ands .

2D epartm ent o f Medica l Psychology, Univers i ty of Limburg, P O Box 616, 64 00 M D Maastr icht, Th e

Nether lands .

3Lucas Found a t i on for R ehabi l it a ti on , Zandbe rgsweg 111 , 6432 CC Ho ensbroek , T he Ne t he r lands .

4Correspondence should be di rec ted to Dr. Johan W. S. Vlaeyen, Ins t i tute for Rehabi l i t a t ion Research,

P.O. Box 192, 6430 AD Ho ensb roek, T he N ether lands.

235

1053-0487/95/1200-0235507.50/0 9 1995 l e n u m u b l i s h i n g Corporation



236 Vlaeyen Kole -Sn ijders Rot teveel R ues in k an d H euts

t

7 d a ~ m 4 w k o

1 7 1 3 8

I I / 1

7 w k s 2 w k s 2 4 w k s

Fig. 1. The na tura l hi s tory of chronic back pa in. Percentage of s ick leave in re la t ion to pa in

dura t ion s ince onse t based o n Spi tzer e t a l . 1987).

with acute back pain resume their work within the period of 4 weeks after the

acute pain onset (Fig. 1). If a worker has not returned to work by 7 weeks, there

is a 50 probability that he/she will be off work at 6 months. About 8 of the

patients still is sick leaving 6 months after the acute pain onset. Similar findings

have been reported by Crook and Moldofsky (2): If a worker has not returned to

work by 3 months, there is a 50 probability that he/she will be off work at 15

months. The relatively small group of chronic back pain patients is responsible

for enormous health care and societal costs (75-90 of the costs) of back prob-

lems (3). What are the reasons for this group to become chronic pain sufferers?

One of possibilities would be that this group has more serious impairments than

the group of workers who resume their work earlier. However, there are no re-

search reports that support this assumption. On the contrary, numerous studies

have shown that there is no perfect relationship between impairments, pain and

disability and suggest that the behavioral or biopsychosocial approach offers the

foundations for a better insight in how pain can become a persistent problem (4-

8). The main assumption is that pain and pain disability are not only influenced

by organic pathology, if found, but also by psychological and social factors. For

example, from a biomedical view, return to work should only be encouraged when

the underlying pathology has healed. Otherwise, the risks of reinjury and repeated

failures would increase, subsequently leading to the promotion of chronicity. From

this biomedical perspective, staying off too long would be much safer than resum-

ing work activities too early. Results reported by Crook and Moldofsky (2), how-

ever, are in support of the conjecture that early return to work contributes to a

decrease in work disability in musculoskeletal pain patients. The arguments include

the recognition that musculoskeletal incidents are enhanced by the immediate con-

sequences such as diminished pain, increased attention from others, avoidance of

unpleasant and fearful situations, and the stabilization of the sick role. Moreover,

longstanding avoidance leads to disuse of the musculature which in turn augments

the deficits in the necessary motoric, social and vocational skills. In other words,

the pain disability is subject to a graded shift from structural/mechanical to cog-

nitive/environmental control. Studies by Deyo

e t a l

(9), Philips and Grant (10),

and Klenerman

e t a l

(11) suggest that this shift occurs quite rapidly, probably

within the period of 4-8 weeks after the acute pain onset.



Fear and Pain Disabil ity 237

Fro m a b eh av i o ra l p e r s p ec t i v e ( ch ro n i c ) p a i n can b es t b e s t u d i ed a s a h y p o -

the t i ca l cons t ruc t , w hich i s no t obse rvab le in i tse l f bu t which can be in fer red on ly

by i t s e f fec t s a t some observab le l eve l . Three observab le l eve l s o r response sys tems

of pa in have b ee n d escr ibe d repea ted ly : psycho-phys io log ica l reac tiv ity , the cogn i -

t ive-percep tua l sys tem, and the over t motor i c sys tem (12) .

P s y c h o P h y s i o l o g i c a l R e a c t iv i ty

When conf ron ted wi th a s t res sor , the ind iv idua l wi l l respond au tomat ica l ly

wi th an increase in symp athe t i c a rousa l. Ev idence ex is ts tha t pa t i en t s wi th low back

pain d i sp lay e leva t ions in parasp ina l e l ec t romyograph ic ac t iv i ty , and de layed re tu rn

to base l ine fo l lowing exposure to persona l ly re l evan t and no t jus t genera l s t res sors

(13). In crea sed sym pathe t i c a rousa l to pa in o r psychosoc ia l s t ressors may con t r ibu te

to a redu ced ab i li ty to to le ra te pa in , and subsequ en t ly to func t iona l limi ta tions and

pain disabi l i ty (14) .

C o g n i t i v e P e r c e p t u a l F a c t o r s

Co g n i t iv e -p e rcep t u a l r e s p o n s es r e f e r t o t h e w ay t h e p a t i en t p e r ce i v es an d i n-

t e rp re t s h i s /her env i ronm ent , and the ex ten t to which he / she th inks tha t con t ro l

can be ing exce r t ed ov er the s i tua t ion . O ne o f the poss ib le a t tr ibu t ions i s tha t pa in

i s a s ign o f a se r ious hea l th p ro b lem , and has been re fe r red to as i llness (o r di s-

ease ) conv ic t ion (15). Such an appra isa l m ay be based on a m is in te rp re ta t ion o f

prop r iocep t ive s ignal s (16) . A co m m on appra i sa l rep or ted b y chron ic pa in pa t i en t s

i s Catas t roph iz ing , re fe r r ing to an a t t en t iona l b ias toward nega tive aspec t s and

exaggera t ion o f the i r s i tua t ion . Catas t roph iz ing i s known to be assoc ia ted wi th in -

creas ing d i s t ress , which in tu rn can increase p a in by reduc ing pa in to le ra nce l eve l s

and by t r igger ing unnecessary sympathe t i c a rousa l (17) .

O v e r t M o t o r i c F a c t o r s

T h e o v e r t -mo t o r i c s y s t em co v e r s o b s e rv ab l e g ro s s mo t o r b eh av i o r s , r e f e r r ed

t o i n p a in r e s ea rch a s p a in b eh av i o r s an d t h e av o i d an ce o f h ea l t h b eh av i o r s an d

ac t iv i ty (4 ) . Pa in can be assoc ia ted wi th verba l and nonverba l express ions , such as

gr imacing , ly ing dow n, the u se o f suppor t ive dev ices , which com m unica te su f fe r ing

t o t h e s o c ia l en v i ro n m en t . Fo rd y c e (4) n o t o n l y i n t ro d u ced t h e co n cep t o f p a i n

behav iors , he a l so app l i ed the operan t cond i t ion ing p r inc ip le to pa in . When pa in

behav ior i s expressed by a pa t i en t , des i rab le th ings can happen (pos i t ive re in fo rce-

m en t ) an d u n p l ea s an t s i tu a t io n s can b e av o i d ed ( av o i d an ce lea rni ng ) . B y m ean s o f

these e nv i ronm enta l in f luences , pa in d i sab i li ty can be m ain ta ined long a f t e r hea l ing

has occ ur red . In th i s paper , w e wi ll focus m ore spec if ica lly o n the m echan i sm of

avoidance learning on pain and disabi l i ty .



238 Vlaeyen Ko le-Sn ijders Rotteveel Ruesink and Heuts

voidance Learning

In 1982 , Fordyce

et al.

(5 ) d e s c r ib ed h o w p a i n b eh av i o r m ay r e s u lt f r o m av o i d -

an ce l earn in g . A v o i d an ce r e f e r s t o t h e p e r fo rm an ce o f a b eh av i o r w h i ch p o s t p o n e s

or aver t s the p resen ta t ion o f an aversive eve n t (18). Avoida nce learn ing has long

b ee n co n s i d e red to u n d e r l y t h e fo rma t i o n o f man y s o -ca l led n eu ro t i c s y m p t o m s

(19). In the case o f pa in , a pa t i en t m ay no longer per fo r m cer t a in ac t iv it ies bec aus e

he / she an t i c ipa tes tha t these ac t iv i t i es increase pa in and su f fe r ing .

In the acu te phase , avo idance behav io rs such as res t ing , l imping , o r the use

o f s u p p o r t iv e eq u i p m en t a r e e f f ec t iv e in r ed u c i n g s u f f e ri n g f ro m n o c i cep t io n . L a t e r

on , these p ro tec t ive pa in and il lness be hav io rs m ay pers is t in an t i c ipa t ion o f pa in ,

ins tead o f as a response to i t . Long las t ing avo idance o f motor i c ac t iv i t i es can have

det r imenta l consequences , bo th phys ica l ly ( loss o f mobi l i ty , musc le s t reng th , and

f i tness , poss ib ly resu l ting in the d i suse syndro m e ) (20) and psycho log ica lly ( loss

o f s e lf - e s te e m , d e p r i v a t i o n o f r e in f o r c e rs , d e p r e s s io n , s o m a t i c p r e o c c u p a t i o n ) .

Ph i l ips and Jaha nshah i (21) foun d tha t, i n a g roup o f hea dac he su f fe rers , avo idanc e

was the mo s t p ro m inen t be hav io r rep or te d by these ind iv iduals . In the i r s tudy ,

av o i d an ce w as n o t l i mi t ed t o av o i d an ce o f mo v emen t , b u t a l s o w i t h d raw a l f ro m

socia l s i tua t ions . Ph i l ips (22) a rgued in favor o f a cogn i t ive theory o f avo idance

behav ior , ra th er than the o pera n t theory . She t akes the v iew tha t a vo idan ce is in-

f luenced by the expec tancy tha t fu r ther exposure to cer t a in s t imul i wi l l p romote

pa in and su f fe r ing . Th i s expec tancy i s as sum ed to be bas ed on p rev ious avers ive

exper iences wi th the same or s imi la r s i tua t ions . She a l so po in ted to the s imi la r i t i es

b e t w een av o i d an ce b eh av i o r d i sp l ay ed b y p a i n p a t i en t s an d t h a t o f p a t i en t s w i th

ex cess iv e f ea r s an d p h o b i as , an d s u g g est s t h a t ch ro n i c p a i n an d ch ro n i c f ea r - -b o t h

av e rs iv e ex p e r ien ces w h ich r e s u lt i n av o i d an ce b eh av i o r - -m ay s h a re i m p o r t an t ch a r -

ac te r i s ti cs (22 , p . 277) . R ece n t s tud ies have focused on the re l a t ionsh ip be tw ee n

fear / anx ie ty and chron ic pa in , o f which the o b jec t o f fear has bee n

f e a r o f p a i n

(23-25) , f ear o f w ork - re l a t ed ac t i v i t i e s (26), and f e a r o f m o v e m e n t t h at is a s s u m e d t o

cause re ) i n j ury

(27-29) .

Fear of Pain

In an a t t em p t t o ex p la in h o w an d w h y s o me i n d iv i d ua l s d ev e l o p a ch ro n ic

p a i n s y n d r o m e , L e t h e m et al. (23) in t roduc ed a so -ca l led fear -av o idan ce m odel .

T h e cen t r a l co n ce p t o f t h e i r m o d e l is f ea r o f p a in . Co n f ro n t a t i o n an d av o i d an ce

a re p o s t u l a t ed a s t h e t w o ex t r eme r e s p o n s es t o th i s f ea r , o f w h i ch t h e fo rm er l ead s

t o t h e r ed u c t i o n o f f ea r o v e r t ime . T h e l a tt e r, h o w ev e r , l e ad s t o t h e m a i n t en an ce

or ex acerba t ion o f fear , poss ib ly l ead ing to a phob ic s t a t e . The avo ida nce resu l t s

in the redu c t ion o f bo th soc ia l and phys ica l ac tivit ies, which in tu rn l eads to a num -

be r o f phys ica l and psycho log ica l con sequ enc es augm ent ing th e d i sab il ity. R ose e t

al. (3 0 ) d em o n s t r a t ed t h e v a li d it y o f th e f ea r - av o id an ce m o d e l i n t h r ee d i f f e r en t

chron ic pa in po pu la t ions , regard less o f the k ind o f pa tho logy p resen t . In 1992 , the

Pa i n A n x i e t y Sy mp t o ms Sca l e (PA SS; 2 4 ) w as d ev e l o p ed t o meas u re co g n i t i v e ,



F e a r a n d P a i n D i s a b i l i ty 3 9

p h y s i o l o g i c , an d mo t o r i c a s p ec t s o f f ea r o f p a i n . T h e au t h o r s fo u n d co r r e l a t i o n s

wi th measures o f anx ie ty , cogn i t ive e r ro rs , depress ion , and d i sab i l i ty . In a second

s tudy (25), the a u thor s sho we d tha t , i n a g roup o f chron ic low-b ack pa in pa t i en t s ,

g rea te r p a in - re la t ed anx ie ty was assoc ia ted wi th h igher p red ic t ions o f pa in and l es s

range o f mot ion dur ing a p rocedure invo lv ing a pass ive bu t pa in fu l s t ra igh t l eg

ra is ing t es t. The y a l so show ed tha t d i f fe ren t types o f pa in -anx ie ty sym ptom s have

d i f f e r en t r e la t io n s w i th p a i n co p i n g r e s p o n s es a s meas u red w i t h t h e Co p i n g S t r a te -

g ies Qu es t ion nai re (CS Q; 31). Cogni t ive anx ie ty response s (e.g. , I f ind it hard to

co n cen t r a t e w h en I h u r t ) n eg a t i v e l y i n t e r f e r ed w i t h co p i n g s t r a t eg y u s e , w h e reas

phys io log ica l anx ie ty responses appeared to enhance cop ing (32) .

M cCra ck en an d G ro s s (2 5 ) al so fo u n d a s u b s tan t ia l o v e r lap b e t w ee n th e CS Q -

fac to r Ca tas t roph iz ing and anx ie ty symptom s . Th i s i s o f in te res t as p rev ious s tud-

i es fou nd s t rong cor re la t ions be tw een ca tas troph iz ing a t t r ibu t ions and d epress ion .

Fea r o f W ork-Related Activities

CLBP pa t i en t s may no t on ly fear pa in , bu t a l so ac t iv i t i es tha t a re expec ted

to cause pa in . In th i s case , fear i s hypo thes ized to genera l i ze to o ther s i tua t ions

tha t a re c lose ly l inked to the feare d s timulus. Vlae yen (33) fou nd tha t a g roup o f

50 CLBP pa t i en t s had mean e leva ted scores tha t were c l in ica l ly s ign i f i can t on the

s o c ia l p h o b i a an d ag o rap h o b i a s ca le s o f t h e Fea r Su rv ey Sch ed u l e (FSS- I I I;

34, 35) . More speci f ical ly , Waddel l

e t a l

(2 6) d ev e l o p ed t h e Fea r -A v o i d an ce Be l i e f s

Q u es t i o n n a i r e (FA B Q ) , fo cu si n g o n t h e p a t i en t 's b e l i e f s ab o u t h o w w o rk an d p h y si -

ca l ac t iv i ty a f fec t h i s /her low back pa in . The FABQ cons i s t s o f two sca les , fear -

avo idance be l i e fs o f phys ica l ac t iv i ty , and fear -avo idance be l i e fs o f work , o f which

the l a t t e r was cons i s t en t ly the s t ronger in p red ic t ing work d i sab i l i ty . The au thors

found tha t fear -avo idance be l i e fs abou t work a re s t rong ly re l a t ed wi th d i sab i l i ty o f

da i ly l iv ing an d w ork los t in the p as t year , and m ore so than b iom edica l var i ab les

such as ana tom ica l pa t t e rn o f pa in , t ime pa t t e rn , and sever i ty o f pa in .

Fear of Movement/ Re)Injury

A m o re s p ec if ic k i n d o f f ea r- av o i d an ce co n ce rn s f ea r o f mo v e m en t an d p h y si -

ca l ac t iv i ty tha t i s (wrongfu l ly ) as sumed to cause ( re ) in ju ry . In accordance wi th

L e t h e m e t a l (2 3 ), C ro m b ez (2 9 ) emp i r ica ll y d e r i v ed a s u b g ro u p o f ' A v o i d e r s an d

Co n f ro n t e r s am o n g a s amp l e o f CL BP p a ti en ts u si n g s e l f- r ep o rt . A l t h o u g h t h e re

w ere n o d i f f e r en ces fo u n d i n g en d e r , ag e , n u mb er o f b ack s u rg er ie s , u s e o f med i -

ca t ion , and repo r ted pa in in tens ity , avo iders rep or ted a h igher f requ enc y o f pa in ,

p a i n o f l o n g e r d u ra t i o n , m o re f ea r o f p ai n , m o re f ea r o f in ju ry , an d m o re a t t en t io n

t o b ack s en s a t i o n s t h an t h e co n f ro n t e r s . W h en ex p o s ed t o a max i ma l p e r fo rman ce

tes t wi th min imal back musc le invo lvement ( f l ex ion and ex tens ion o f the knee) ,

conf ron ters showed a s ign i f i can t ly be t t e r per fo rmance than the avo iders . Regress ion

an a l y se s r ev ea l ed t h a t w h en v a r i an ce d u e t o g en d e r , ag e , an d b o d y w e i g h t w as co r -



240 Vlaeyen Kole-Sn i jders Rot teveel Rue sink an d Heu ts

rected for, behavioral performance was significantly predicted by both reported fear

of pain and reported fear of injury.

Kori et al . (27) introduced the term kinesiophobia (kinesis = movement)

for the condition in which a patient has

a n e x ce s siv e , i r ra t io n a l , a n d d e b i l i t a t i n g f e a r

o f p h y s i c a l m o v e m e n t a n d a c ti v it y r e su l ti n g f r o m a f e e l in g o f v u ln e r a b il it y t o p a i n f u l

i n j u r y o r r e i n j u r y . These authors also developed the Tampa Scale for Kinesiophobia

(TSK) as a measure for fear of movement/(re)injury. The TSK consists of 17 items,

each of which are provided with a 4-point Likert scale. In a previous study using

a Dutch version of the TSK (36), we found that fear of movement/(re)injury appears

to be related to gender and compensation status, when variance due to current

pain intensity was corrected for. However, even stronger associations were found

with catastrophizing and depression, rather than with pain intensity and pain coping.

Furthermore, subjects who report a high degree of fear of movement/(re)injury

showed more fear and escape/avoidance when exposed to a simple movement con-

sisting of lifting a 5.5-kg bag. They also quit lifting the bag significantly sooner than

the less fearful patients. This study also supports the validity of the TSK-DV in

distinguishing CLBP patients suffering from high and low fear of movement/(re)in-

jury. However, as also noted by Crombez (29), one of the problems is that it remains

difficult to disentangle whether the bad performance is caused by fear or by physical

limitations due to mechanical back problems, or by current pain intensity levels.

In this paper, two studies will be presented. The first study examines the factor

structure of the Tampa Scale for Kinesiophobia (TSK-DV), and the validity of the

factors found. In the second study, an experiment was set up to analyse the value

of fear-avoidance beliefs in predicting disability levels, when biomedical status of

the patient and current pain intensity levels are taken into account. Second, prin-

cipal determinants of fear-avoidance beliefs were looked for.

STUDY

:

FACTOR STRUCTURE OF THE TSK-DV

M e t h o d

S u b j e c t s

One hundred and twenty-nine CLBP patients that were admitted to the

Hoensbroek Rehabilitation Center for an inpatient behavioral rehabilitation pro-

gram were included in this study. The sample consisted of 50 men and 79 women

with a mean age of 40.1 years (SD = 9.0). The duration of pain complaints was

9.9 years (SD = 8.8). Of the total sample, 63.9% received financial disability com-

pensation for at least 1 year, with a mean duration of 3.7 years (SD = 4.7), 38%

had received one or more back surgeries, and 24.8% used supportive equipment

for ambulation. All patients had minimal organic findings or displayed pain com-

plaints that were disproportionate to the demonstrable organic basis of their pain.



F e a r a n d P a i n i s a b i l it y

24

Measures

Pain Intensity. The Pa i n Ra t i n g In d ex (PRI - t o t a l ) s co re o f t h e D u t ch v e r s i o n

o f t h e M cG i l l Pa i n Q u es t i o n n a i r e (MP Q -D V ; 3 7 , 3 8 ) a w i d e l y u s ed m eas u re o f

pa in exper ience , i s used in th i s s tudy .

Pain Cogni t ions . The Pain Cogni t ion L i s t (PCL-e ; 39) i s a 77- i t em ques t ion-

n a i r e a i med a t t h e a s s e s s men t o f d i s to r t ed p a i n co g n i t io n s an d ex p e r i en ced s e lf -

con t ro l . F ive sca les a re fac to r -ana ly t i ca l ly der ived : Pa in Impact , Ca tas t roph iz ing ,

O u t co me-E f f i cacy , A cq u i e s cen ce , an d Re l i an ce o n H ea l t h ca r e . Fo r t h i s s t u d y o n l y

the subsca les Pa in impac t and Catas t roph iz ing we re se lec ted . Pa in imp act re f l ec t s

the ex ten t to which the pa in in te r fe res wi th da i ly ac tivit ies. Catas t roph iz ing re fe rs

to an a t t en t iona l fo cus on nega t ive aspec t s o f the pa t i en t ' s s i tua t ion .

Fear o f M ovement / Re) In jury . A D u t ch v e r s i o n o f t h e T amp a Sca l e fo r K i n e -

s iophobia (27 , 36) i s a ques t ionnai re tha t i s a imed a t the assessment o f fear o f

( r e ) in j u ry d u e t o m o v em en t . T h e o r ig in a l 1 7- item T S K w as tr an s l a ted i n to D u t ch

(T SK -D V ) b y t h e au t h o r s an d s u b s eq u en t l y co r r ec t ed b y a p ro fe s s i o n a l t r an s l a t e r .

T h e s am e s co r in g fo rma t an d k ey s w ere m a i n ta i n ed . E ac h i tem is p ro v i d ed w i th a

4-po in t L iker t sca le wi th scor ing a l t e rna tives rang ing f rom s t rong ly d i sagree to

s t rong ly agree . A to ta l score i s ca lcu la ted a f t e r invers ion o f the ind iv idua l scores

of i tem s 4, 8 , 12 , and 16 . Ba sed on the d a ta o f the c ur ren t p a t i en t sam ple , fo llowing

i n fo rma t i o n u n d e r s co re s t h e r e li abi li ty o f t h e T SK -D V . A cco rd i n g t o t h e K o l m o g o -

ro v -Smi rn o v g o o d n es s -o f - f i t t e s t , t h e s co re s o n t h e T SK w ere n o rma l l y d i s t r i b u t ed

(K-S, z = .820, p = 0 .512) . C ron ba ch 's a lpha w as 0 .77, wh ich is fair . Th ese da ta

are cons i s t en t wi th an ear l i e r s tudy us ing a d i f fe ren t ch ron ic pa in sample (28) .

Fear . T he D u t ch v e r s i o n o f t h e Fea r Su rv ey Sch ed u l e (FSS- I I I -R ; 3 4 , 3 5 ) i s

used . The FSS-I I I -R i s a 76- i t em ques t ionnai re cons i s t ing o f c lus te rs o f phob ic com-

p la in t s : Soc ia l Pho b ia , Ag orap hobia , Fe ar o f Bodi ly In ju ry , Il lness and D eath , Fe ar

of Sex and Agg ress ion , and Fe ar o f L iving O rgan i sms . Fo r th is s tudy on ly the c lus te r

fear o f Bod i ly In ju ry , Il lness , and D eath i s se l ec ted .

P a i n Co n t r o l Th e Pa i n Co n t ro l s ca le o f a D u t ch v e r s io n o f t h e Co p i n g S t r a t e -

g ies Q ues t ion nai re (31), dev e lop ed by Sp inhoven a nd L inssen (40) wa s se lec ted fo r

this s tudy.

r o c e d u r e s

T h e 1 7 T S K i t ems w e re s u b j ec t ed t o a p r in c i p a l co m p o n en t an a l y si s w i t h

ob l iqu e ro ta t ion . I t em s wi th a fac to r load ing < .40 on a l l fac to rs w ere exc luded .

Fo r t h o s e i t ems h av i n g h i g h f ac t o r l o ad i n g s o n mo re t h an o n e f ac t o r , t h e i t em w as

ass igned to one o f the fac to rs based on i t s con ten t s . For each fac to r , i n t e rna l con-

s i s t ency (Cronbach ' s a lpha) i s ca lcu la ted . In o rder to as sess the va l id i ty o f the TSK

s u b s ca l e s d e r i v ed , co r r e l a t i o n s a r e ca l cu l a t ed amo n g t h e s u b s ca l e s an d a n u mb er

of con cur re n t m easu res inc lud ing ca tas troph iz ing , p a in impact , pa in con t ro l, pa in

intensi ty , and fear .



24 2 Vlaeyen Kole -Sn ijders Rot teveel Ru es ink an d H euts

T a b l e I . Comp onent S t ruc ture of the TSK-DV: Component s, In t e rna l Consis tency (C ronbach ' s

Alpha), Correlation with TSK Total Score (r'rSK-TOT),and Component Label with Respective

I t ems

Component Alpha rTSK.TOTLabel

I .71 .72* TSK -H:

11.

II .63 .56*

Il l .53 .38*

IV .61 .57*

H arm

I wouldn't have this m uch pa in i f there were n' t something

potentially dangerous going on in my body.

3. M y body is tell ing me I have something dangerously wrong.

6. M y accident has pu t my body at risk for the rest of my life.

TSK-F: F ear o f (re)injury

9. I am afraid that I might injure myself accidentally.

1. I am afraid that I might injure myself if I exercise

TSK-E: Importance of exercise

14. It 's really not safe for a person with a condition like mine

to be physically active.

4.a M y pain would probably be relieved if I were to exercise.

12.a Although my condition is painful, I would be be tter off if I

were physically active.

TSK-A: Avoidance of activity

2. If I were to try to overcome it, my pain would increase.

13. Pain lets me kn ow when to stop exercising so that I do n't

injure myself.

15. I can ' t do all the things normal peo ple do because i t 's too

easy for me to get injured.

10. Simply being careful that I do not make any unnecessary

movements is the safest thing I can do to prevent my pain

from worsening.

aFor these i tems, scores are inversed.

*p _< .001 (on e-tailed ).

R e s u l t s

B a s e d o n t h e ~ 2 - te s t f o r th e s u f f i c i en t n u m b e r o f fa c t o r s e x t r a c t e d a n d t h e

i n t e r p r e t a b i l i t y o f t h e f a c t o r s , t h e s o l u t i o n o f f o u r f a c t o r s w a s c h o s e n ( T a b l e I ) w h i c h

c u m u l a t iv e l y a c c o u n t e d f o r 3 6 . 2 o f t h e t o t a l v a r i a n c e (1 5 .5 , 5 . 6 , 8 . 6 , a n d

6 . 5 , r e s p e c ti v e ly ) . F a c t o r s w e r e l a b e l e d fo l lo w i n g t h e c o m m o n p r o c e d u r e o f g i v in g

t h e g r e a t e s t c o n s i d e r a t i o n t o i t e m s w i t h h i g h l o a d i n g s o n e a c h f a c to r .

T h e f o l lo w i n g l a b e ls w e r e a s s ig n e d :

Harm

( T S K - H ) ,

Fear o f re)injury

( T S K - F ) ,

Impo rtance o f exercise

( T S K - E ) , a n d

Avoida nce o f activity

( T S K - A ) . T h e i n t e r n a l c o n -

s i s te n c y o f t h e f a c t o r s r a n g e s f r o m .5 3 (T S K - E ) t o .7 1 ( T S K - H ) a n d a r e l o w e r t h a n

a l p h a o f t h e T S K - t o t a l s c o r e ( .7 7 ). I n t e r c o r r e l a t i o n s a m o n g t h e T S K - D V f a c t o r s

r a n g e f r o m .0 2 to ( - ) .3 1 ( T a b l e I I ) , w h i c h s u g g e s t s th a t t h e f a c t o r s a r e n o t t o t a l l y

i n d e p e n d e n t . T h e p a t t e r n o f c o r r e l a t io n s w i th c o n c u r r e n t m e a s u r e s ( T a bl e I I I ) s u g -

g e s t s t h a t t h e T S K - H a n d T S K - F f a c to r s a r e m o s t r e f l e c ti v e o f th e c o n s t r u c t o f f e a r

o f m o v e m e n t / ( r e ) i n j u r y . A l t h o u g h t h e y a r e n o t s t r o n g l y c o r r e l a t e d ( r = . 2 3 ) t h e i r

p a t t e r n o f c o r r e l a t io n s w i t h th e c o n c u r r e n t m e a s u r e s a r e q u i t e s i m i la r . T h e c o r r e -

l a t i o n s p r e s e n t e d i n T a b le I I I f u r t h e r s u g g e s t s t h a t f a c t o r s T S K - E a n d T S K - A s e e m

t o m e a s u r e d i f f e r e n t c o n s t r u c t s . A n o t h e r i n t e r e s t i n g f i n d i n g is t h a t n o s i g n i f i c a n t



F e a r a n d P a i n D i s a b i l i t y

T a b l e

IL Intercorrelations Am ong T SK-D V Subscales

T SK -F T S K - E T S K - A

TS K-ha rm -.23 .30 .21

TS K-fear of (re)injury -.15 -.31

TSK-exercise .02

4 3

Table IlL Correlations Am ong TSK Subscales and Pain Impact (PC L-e), Catastrophizing (PCL-e),

Outcome-Efficacy (PCL-e), Acquiescence (PCL -e), Reliance on Health Ca re (PCLoe), Pain Control

(CSQ), Pa in Intensity (MPQ ), and Fear of Bodily Injury, Illness and Death (FSS-III-R)

T SK -H T SK -F T SK -E T S K - A T S K - T O T

Pa in im pact .23* .38** .01 .13 .27*

Cata stroph izing .47 * .52 * .06 .35 ** .54**

Pa in inten sity .24* .25* .11 .16 .21

Pain con trol .02 .09 -.03 -.16 -.10

Fe ar of blo od , inju ry .32** .37** -.15 .14 .32**

*p < .01.

**p < .001 (one-tailed).

c o r r e l a ti o n s a r e f o u n d b e t w e e n P a i n C o n t r o l a n d a n y T S K s u b s ca le , w h i c h s u g g e st s

t h a t t h e T S K t a p s a p a r t i c u l a r a s p e c t o f b e l i e fs t h a t i s m o r e r e l a t e d t o t h e i n t e r -

p r e t a t i o n , a t t r i b u t i o n o r a p p r a i s a l o f t h e s i tu a t i o n , r a t h e r t h a n t o e x p e c t a n c i e s a b o u t

s e l f - ef f i c ac y a n d p a i n c o n t r o l . D e s p i t e t h e f o u r - f a c t o r s o l u t io n , a r g u m e n t s c a n b e

f o r m u l t a t e d i n fa v o r o f t h e u s e o f th e T S K t o t a l sc o r e, r a t h e r t h a n t h e f a c to r s .

T h e s e a r e: t h e r e la t iv e l y h i g h i n te r c o r r e la t i o n s a m o n g s o m e o f th e f a c to r s , th e m o r e

f a v o r a b l e i n t e r n a l c o n s i s t e n c y o f t h e t o t a l s c o r e , a n d t h e g o o d c o n s t r u c t v a l i d it y o f

t h e t o t a l s c o r e a s d i s p l ay e d b y t h e p a t t e r n o f c o r r e l a t i o n s w i t h c o n c u r r e n t m e a s u r e s .

S T U D Y 2 : D E T E R M I N A N T S O F P A IN D I S A B I L IT Y A N D F E A R O F

M O V E M E N T / ( R E ) I N J U R Y

T h i s s t u d y w a s fi rs t a im e d a t e x a m i n i n g w h e t h e r f e a r o f m o v e m e n t / ( r e ) i n j u r y

is a m a j o r p r e d i c t o r o f p a i n d i sa b il it y , as c o m p a r e d w i t h c u r r e n t p a i n i n t e n s i t y le v e ls ,

c a t a t s tr o p h i z i n g a n d l ev e ls o f i m p a i r m e n t , a f t e r c o n t r o ll in g f o r d e m o g r a p h i c v a r i-

a b le s . T h e s e c o n d a i m o f th i s s tu d y w a s to e x a m i n e w h e t h e r c a t as t ro p h i z in g , r a t h e r

t h a n c u r r e n t - p a i n i n te n s i ty a n d l ev e ls o f i m p a i r m e n t , is p r e d i ct i v e o f f e a r o f m o v e -

m e n t / ( r e ) i n j u r y .

M e t h o d

ubjec ts

T h i r t y - t h r e e c h r o n i c l o w b a c k p a i n p a t i e n t s w h o w e r e o n a w a i t i n g l i s t f o r a

b e h a v i o r a l r e h a b i l i t a t i o n p r o g r a m a g r e e d t o p a r t i c i p a t e i n t h e e x p e r i m e n t . T h e



244 Vlaeyen Kole-Snijders Rotteveel Ruesink and Heuts

g ro u p co n s i s t ed o f 1 7 f ema l e an d 1 6 ma l e p a t i en t s w i t h a mean ag e o f 3 7 .4 y ea r s

(S D = 9 .2, ran ge = 22-53) .

The mean dura t ion o f the i r pa in compla in t s was 7 .6 years (SD - - - 8 .2 ; range

= 0.7-29) . As is s tudy 1 , a l l pat ients had minimal demonstrable organic f indings .

Measures

L e v e l o f I m p a i rm e n t

T h e M e d i c a l E v a l u a t i o n a n d D i a g n o s t i c I n f o r m a t i o n

Co d i n g s y s t em (ME D ICS; 4 1 ) w as u s ed b y a r eh ab i l i t a t i o n p h y s i c i an t o q u an t i fy

t h e b i o m ed i ca l s ig ns an d s y mp t o ms th a t m ay b e r e l a t ed t o t h e p a t i en t s ' r ep o r t s o f

p a i n. M E D IC S w as co m p l e t ed a f t e r ex ami n a ti o n o f t h e m ed i ca l ch a r t o f th e p a t i en t .

For th i s s tudy , the to ta l pa tho logy score us ing the medica l concensus weigh t s re -

p o r t e d b y R u d y

et al

(41) i s used.

Pa in In tens it y T he

Visua l An alog Sca le (VAS; 42), a wide ly used m eas ure o f

pa in exper ience , i s used in th i s s tudy . Pa t i en t s were asked to ra t e the mean pa in

in tens ity over the l as t we ek . A 10 cen t ime ter l ine was p rov ide d wi th wr i t t en ancho rs

a t the two ex t remes : no pa in a t a l l and the wo rs t pa in eve r expe r i enced .

Pain Cogni t ions

Fo r th is s tudy , the sub sca le Catas t roph iz ing o f the Pa in Cog -

n i t ion L i s t (PCL-e ; 39) i s se l ec ted .

Fear

A Dutch vers ion o f the Tampa Sca le fo r Kines iophobia (TSK-DV; 36) i s

a q u es t i o n n a i r e t h a t i s u s ed fo r t h e a s s e s smen t o f f ea r o f ( re ) i n ju ry d u e t o m o v e -

men t .

Le ve l o f Disabil it y O n e o f t h e b es t d ev e l o p ed s e l f - r ep o r t m eas u re s o f d i sab i li ty

in ac t iv i t i es o f da i ly l iv ing , the Roland Disab i l i ty Ques t ionnai re (RDQ; 43) i s used

in this study.

P r o c e d u r e

W he n en ter ing the l abora to ry , all pa t i en t s were g iven b r i e f in fo rm at ion a bo u t

t h e ex p e r imen t . Su b s eq u en t l y t h ey w ere r e q u es t ed t o co m p l e t e t h e q u es t i o n n a i re s .

T h e n t h e s u b j ec t s w e re a s k ed t o p e r fo rm s ev en act iv i ti e s t h a t w e re p a r t o f an o t h e r

s t u d y ex ami ni n g t h e i n fl u en ce o f p r io r ex p ec t a t i o n s o n b eh av i o ra l p e r fo rma n ce (4 4 ).

T h e ex p e r i men t e n d ed w i th t h e co mp l e t i o n o f a n u m b er o f q u es t i o n s r eg a rd i n g

t h e i r p e r fo rman ce , an d t h e i r b e l ie f s ab o u t f ea r o f mo v em en t / (r e ) in j u ry .

S t a t i s t i c s

Pea r s o n co r r e la t io n co e f fi c ien t s amo n g T SK -D V , R D Q , an d o t h e r v a r i ab l e s

are ca lcu la ted . T- t es t s fo r the d i f fe rences be tween low-d i sab led and h igh-d i sab led

s u b j ec ts (R D Q ) , an d b e t w ee n l o w - fea r an d h i g h - f ea r su b j ec ts (T SK -D V ) b as ed o n

a med i an s p li t f o r RD Q , an d a cu t -o f f s co re o f 3 7 fo r T SK -D V (3 6 ) a r e ca r r i ed

o u t fo r t h e i n d ep en d en t v a r i ab l e s .

Hierarc h ica l m ul t ip le regress ion ana lyses wi th a s t epwise fo rwa rd inc lus ion

m e t h o d w i th T SK -T o ta l s co re an d R D Q as d ep en d en t v a r i ab l e s w e re u s ed . Pa i n



F ea r a nd P a i n D i s a b i l ity 4 5

dura t ion and gender were en te red in to the equa t ion f i r s t , t o t e s t whe the r one o f

the o th e r ind epe nd en t va r i ab les (M ed ics, Pa in in tens ity , Ca tas troph iz ing ) wou ld

con tr ibute s ignificantly to th e var iance in the d ep en de nt var iable af ter contro l l ing

for these socio-de m ograp hic variables.

esul t s

Question

As displaye d in Table IV, R D Q corr elate s s ignificantly only with TSK-DV. Co r-

r e la tions w i th gend er and com pensa t ion s ta tus were low ( r= - .17 and .13 , r e spec -

t ively) . Th e only s ignif icant differe nce s be tw ee n the high an d low disabil ity subjec ts

was on T SK-DV and Catas t rophiz ing (Table V) . Con sequent ly , Table VI shows that

among the va r i ab les en te red in the r eg res s ion mode l , f ea r o f movemen t / ( r e ) in ju ry

is the bes t pre dic to r of pain d isabil ity as mea sure d by the RD Q . O f in teres t i s tha t

catas t rophiz ing , which is predic t ive for fear , does not d i rec t ly predic t pain d isabil ity.

How ever , the pe rcen tage o f exp la ined va r i ance is r a the r mo des t (13 ) . On the

other hand, pain in tens i ty and b iomedical f indings were not predic t ive of pain d is -

ability.

Ta bl e IV. Means, SD for Age, Du ra t ion of Pa in Years) , C urrent Pa in Intensity VAS),

Catas trophiz ing PCL -e) , Level of Imp ai rmen t Medics) , Fea r of M ove me nt / Re)In jury

TSK -DV ), and Pain Disabi li ty RD Q) , and Pearson C orre la t ion Coeff ic ients r wi th

T S K - D V an d R D Q

M e a n S D r w ith T S K - D V r w i th R D Q

A ge years) 37.4 9.2 -.26 .03

Pain dura t ion years) 7.6 8.2 - .45* - .33

Pain intensi ty VA S) 51.6 22.2 .00 .23

Catas troph izing PC L-e) 48.2 13.1 .49* .29

Imp ai rm ent medics) - .70 .78 .15 .04

Fea r o f mo vem ent TSK -DV ) 40 .4 6 .6 - - .49*

Pain disabil ity R D Q ) 13.8 4.2 .49* --

*p < 0.01 one-ta i led) .

Ta bl e V. t -Tests for the D i fferences Betw een Low-Disabled Subjec ts RD Q _< 15) and H igh-Disabled

Subjec ts R D Q > 15)

Low -disability subjects High-d isability subjects

n = 1 8 ) n = 1 5 )

M e a n S D M e a n S D p

A ge years) 36.7

Pain dur a t ion years) 7.4

Pain intensi ty V A S) 45.4

Catas t roph iz ing PCL -e) 44.1

Imp a i rment medic s) - . 59

F e a r o f m o v e m e n t T S K - D V ) 3 8.1

Pain disabil ity R D Q ) 10.7

9.5 38.2 9.1 NS

7.0 7.9 9.7 NS

20.7 59.0 22.4 N S

14.3 53.0 9.9 .050

.67 - .82 .88 NS

7.0 43.3 4.9 .022

3.0 17.5 1.4 .000



246 Vlaeyen Kole -Sn ijders Rot teveel Ru es ink an d He uts

T a b l e VI. Summary o f Stepwise Hierarchical Regression Analysis of P ain Disabil ity (RD Q), with

Pain Duration and Gend er Entered in the First Step and Variables Fear o f M ovem ent/(Re)Injury

(TSK -TOT ), Catastrophizing (PCL -e), Pa in Intensity (VAS), and Biom edical Findings (MED ICS)

Tested with a Forward Inclusion Methoda

A d . l l

Step Independent variables R 2 R2 Beta

1. Pain duration .04 .12 -.37

Gender .07

2. Pain duration .17 .27 -.19

Gender .12

Fear of mo vemen t/(re)injury (TSK -TOT ) .44*

Depen dent v ariable: Level of pain disability (RD Q). Variables not in the equation: pain intensity (VA S),

catastrophizing (PC L-e), biomed ical findings (ME DIC S).

*p _< 0.0 5.

T a b l e VII. t-Tests for the Differences Between L ow-Fear Sub jects (TSK -DV _< 37) and High-Fear

Subjects (TSK-DV > 37)

Low -fear subjects High-fear subjects

(n = 11) (n = 22)

Mean SD Mean SD

Ag e (years) 39.2 10.1 36.5 8.9 NS

Pain duration (years) 9.6 8.2 6.6 8.2 NS

Pain intensity (VA S) 44.4 16.0 55.2 24.3 NS

Catastro phizing (PC L-e) 41.5 11.9 51.5 12.6 .038

Imp airme nt (med ics) -.84 .55 -.64 .86 NS

Fea r of mo vemen t (TSK -DV ) 33.3 3.4 44.0 4.6 .000

Pain disability (R D Q ) 10.7 3.8 15.3 3.5 .002

Question

A s d i s p l a y e d i n T a b le IV , a n d c o n s i s t e n t w i t h p r e v i o u s f i n d in g s , T S K - D V c o r -

r e l a t e s s i g n if i c an t l y w i t h c a t a s t r o p h i z i n g a n d p a i n d i sa b il it y , a n d n e g a t i v e l y w i t h p a i n

d u r a t i o n . T h e r e w a s a m o d e s t c o r r e l a t io n w i t h g e n d e r ( r = . 2 0 ) b u t , in c o n t r a s t t o

p r e v i o u s f in d i n g s ( 36 ) , n o t w i th c o m p e n s a t i o n s t a t u s ( r = . 0 8 ) . D i f f e r e n c e s b e t w e e n

h i g h a n d l o w f e a r fu l s u b je c t s a r e f o u n d f o r m e a s u r e s o f c a t a s t r o p h i z i n g a n d p a i n

d is a bi li ty ( T ab le V I I ) . A s s h o w n i n Ta b le V I I I , f e a r o f m o v e m e n t / ( r e ) i n j u r y c a n b e s t

b e p r e d i c t e d b y ca t a s tr o p h i z in g , w h i c h a c c o u n t e d f o r a n a d d i t io n a l 1 7 % o f t h e v a r i-

a n c e , b e y o n d t h e 1 5 % p r e d i c t i o n b y g e n d e r a n d p a i n d u r a t i o n s i m u l t a n e o u s ly . P a i n

i n te n s i ty a n d b i o m e d i c a l f in d i n g s d id n o t a d d a n y p r e d ic t iv e v a l u e t o t h e j u s t - m e n -

t i o n e d v a r i a b l e s .

D I S C U S S I O N

A v o i d a n c e b e h a v i o r i s p o s t u l a t e d t o b e o n e o f th e m e c h a n i s m s i n s u s t a in i n g

c h r o n i c p a i n d i sa b il it y . I n t h e a c u t e p a i n s i tu a t i o n , a v o i d a n c e o f d a i ly a c ti v it ie s t h a t



F ea r a nd P a i n D i s a b i li ty 4 7

T a b l e

VIII. Sum mary of S tepwise Hierarchical Regression Analysis of Fear of Movem ent

(TSK-TOT), w ith Pain D uration and G ende r En tered in the First Step and V ariables

Catastrophizing (PCL -e), Pain Intensity (VAS), and Biomedical Findings (MED ICS)

Tested w ith a Forw ard Inclusion Method

m d . l l

Step Independentvariables Rg R2 Beta

1. Paindu ration .15 .21 -.40

Gender -.11

2 . Pa induration .32 .40 -.28

Gender -.19

Catastrophizing (PC L-e) .45*

aDependent variable: Fear of movement/(re)injury(TSK-DV ). Variables not in the equa tion: pain

intensity (V AS), biomedical findings (ME DICS).

*p _< 0.05.

i n c rea s e p a i n i s a s p o n t an eo u s an d a d ap t i v e r eac t i o n o f th e i n d i v i d u a l (4 5 ) ; it u s u a l l y

a l l o ws t h e h ea l i n g p ro ces s t o o ccu r . In ch ro n i c p a i n p a t i en t s , h o wev e r , av o i d an ce

b e h a v i o r a p p e a r s t o p e r s is t b e y o n d t h e e x p e c t e d h e a l i n g ti m e . O n e o f t h e r e a s o n s

t h a t a v o i d a n c e b e h a v i o r s p e r si s t is n o t o n l y t h e s h o r t - t e r m e f f e c t s o f r e d u c e d s u f-

f e r i n g , b u t a l s o t h e i n f l u en ce o f ce r t a i n b e l i e f s an d ex p ec t a t i o n s (2 2 ) . I f t h e i n d i -

v i d u a l b e l i e v e s t h a t f u r t h e r e x p o s u r e t o c e r t a i n s t i m u l i w i ll i n c r e a s e p a i n a n d

s u f fe r i n g , av o i d an ce o r e s cap e wi ll b e l i k el y t o o ccu r . So f a r , l i t tl e s c ien t i fi c a t t en t i o n

h as b e en d raw n t o t h e s p ec i f i c b e l i e f s t h a t a r e r e l a t ed t o a v o i d an ce . In t h i s a rt ic l e ,

a p a r t i c u l a r b e l i e f is p u t f o r w a r d t h a t i s h y p o t h e s i z e d t o e n h a n c e a v o i d a n c e , n a m e l y

t h e e x p e c t a t i o n t h a t m o v e m e n t c a n c a u s e ( r e ) i n j u r y , a n d t h u s i n c r e a s e d s u f f e r i n g .

T h e f ir s t s t u d y sh o w s t h a t t h e T S K - D V i s c o m p o s e d o f f o u r fa c t o rs : H a r m ,

F e a r o f i n j ur y , I m p o r t a n c e o f e x e rc is e , a n d A v o i d a n c e , w h i c h a r e n o t t o ta l l y i n d e -

p e n d e n t . B a s e d o n b o t h t h e i n t e r c o r r e l a t io n s a m o n g t h e f o u r f a ct o rs , th e r e l i ab i li ty

c o e f f ic i e n ts , a n d t h e v a l i d it y d a t a i t c a n b e c o n c l u d e d t h a t t h e T S K - D V c a n b e u s e d

a s a s i n g le f a c t o r a s w e ll . T h e s e c o n d s t u d y r e v e a l e d t h a t f e a r o f m o v e m e n t / ( r e ) i n -

j u ry i s t h e b e s t p re d i c t o r fo r s e l f - r ep o r t ed d i s ab i li ty l eve l s, r a t h e r t h an b i o m ed i ca l

f i n d in g s , p a i n i n t e n s i t y le v e ls , a n d c a t a s t ro p h i z i n g . T h e s e c o n d f i n d i n g w a s t h a t

c a t a s t ro p h i z i n g , r a t h e r t h a n p a i n i n t e n s it y r a t in g s a n d b i o m e d i c a l f i n d in g s is p r e -

d i c ti v e o f f e a r o f m o v e m e n t / ( r e ) in j u r y . A n u n e x p e c t e d f i n d i n g is t h e n e g a t i v e c o r -

r e l a t i o n b e t w e e n f e a r o f m o v e m e n t / ( r e ) i n j u r y a n d p a i n d u r a t i o n , a n d w o u l d s u g g e s t

t h a t t h is p a r t i c u l a r f e a r e x t in g u i s he s w i t h t i m e , o r t h a t m o r e c h r o n i c al l y d i s a b l e d

p a t i e n t s a r e l e ss l ik e l y t o ack n o w l ed g e f ea r . Fu t u re s t u d i e s n ee d t o c l a r i fy t h i s is s u e .

B e c a u s e o f t h e r e l at i v el y s m a l l s a m p l e s i z e, t h e u n e x p e c t e d a s s o c ia t io n m a y b e c o -

i n c i d en t a l a s we l l .

A l t h o u g h p o s i t iv e c o r r e l a t i o n s m a y n o t b e c o n f u s e d w i t h c a u s a l e f fe c t s, b o t h

f i n d i n g s u n d e r s co re p a r t s o f a co g n i t i v e -b eh av i o ra l m o d e l d i s p l ay ed i n F i g . 2 . Th i s

m o d e l r e p r e s e n t s t h e m e c h a n i s m h o w f e a r o f m o v e m e n t / ( r e ) i n j u r y p o s si b ly c o n t r ib -

u t e s t o t h e m a i n t e n a n c e o f c h r o n i c p a i n d i s a b il it y i n c h r o n i c l ow b a c k p a i n , s t a r t in g

w i t h t h e i n j u r y o c c u r i n g d u r i n g t h e a c u t e p h a s e . T h e p a i n f u l e x p e r i e n c e s , t h a t a r e

i n t en s i f i ed d u r i n g m o v e m en t , w i ll e li c it c a t a s t ro p h i z i n g co g n i t i o n s i n s o m e i n d i v i d u -

a l s a n d m o r e a d a p t i v e c o g n i t io n s i n o t h e r s.



248 Vlaeyen Kole .Sn ijders Rot teveel Ru es ink and H euts

A s d emo n s t r a t ed i n s t u d y 2 , c a t a s t ro p h i z i n g ap p ea r s t o b e a p o t en t p r ed i c t o r

o f fear o f movement / ( re ) in ju ry . S t i l l unknown i s whether cas tas t roph iz ing i s a t ra i t -

l ike d i spos i t ion tha t t riggers fear o f m ovem ent / ( re ) in ju ry when the ind iv idua l en -

co u n t e r s an acu t e p a i n ep i s o d e , o r w h e t h e r ca t a s t ro p h i z i n g i s mere l y p a r t o f t h e

cogn i t ive responses assoc ia ted wi th fear o f movement / ( re ) in ju ry . In the f i r s t case ,

ca tas t roph iz ing ind iv idua l s may focus more on the nega t ive aspec t s o f the acu te

pain s i tuat ion, and are more l ikely to in terpret physical arousal as pain s ignals . As

a resu l t o f th i s a t t en t iona l focus , in t e rocep t ive in fo rmat ion tha t o f t en i s as soc ia ted

w i t h m o v em en t is m o re ea si ly n o t i ced an d p e rh ap s i n t e rp re t ed a s d an g e ro u s o r

s ignal ing ( re ) in ju ry . Th e op pos i t e migh t be t rue as well . As Turk and Ho lzm an

(46) have sugges ted , fear -avo idance be l i e fs may espec ia l ly be the case when the

or ig ina l acu te pa in p rob lem resu l t ed f rom t raumat ic in ju ry . Indeed , when the sub-

j ec t s f ro m s t u d y 2 w ere a s k ed ab o u t t h e c i r cu ms t an ces o f t h e acu t e p a i n , p a t i en t s

w h o r ep o r t ed t r au ma t i c p a i n o n s e t ( s u d d en o n s e t a s s o c i a t ed w i t h b e i n g f r i g h t en ed )

scored h igher on ca tas t roph iz ing (bu t no t s ign i f i can t ly ) and on the TSK-DV (s ig -

n i f ican t ly ) t h an s u b j ec t s w h o r e t ro s p ec t iv e l y r ep o r t ed t h a t t h e p a i n co m p l a i n t s

s t a r t ed g radual ly . The recen t p rospec t ive s tudy by Bur ton e t a l (47) , searching for

p red ic to rs o f ch ron ic i ty a t 1 yea r is wo r th m ent ion ing in th is con tex t . These re -

s ea rch e r s fo u n d t h a t c a ta s tro p h iz i n g, a s meas u red b y t h e C SQ , w as t h e m o s t p o w -

er fu l p red ic to r , and a lmos t 7 t imes more impor tan t than the bes t o f the c l in ica l

and h i s to r i ca l var i ab les fo r the acu te back pa in pa t i en t s .

Fea r o f mo v emen t / ( r e ) i n j u ry s u b s eq u en t l y l e ad s t o i n c r ea s ed av o i d an ce ( a s

d e m o n s t r a te d b y C r o m b e z ( 2 9 ) a n d V l a e y e n e t a l (36) ) , and in the long run to

d i suse , depress ion and increased d i sab il ity (22 , 48). B o th d epress ion and d i suse a re

known to be assoc ia ted wi th decreas ing pa in to le rance l eve l s (49 , 50) , and hence

promot ing the pa in fu l exper i ences . In pa t i en t s wi th adap t ive cogn i t ions , conf ron ta-

t ion ra ther than avo idance i s l ike ly to occur , p romot ing hea l th behav io rs and ear ly

recovery .

Th i s s tudy , as the s tud ies by Rose e t a l (30) and Waddel l e t a l . (26) , p rov ides

s u p p o r t f o r t h e v a l id i ty o f t h e f ea r - av o i d an ce co n cep t . I t s h o u l d b e n o t ed , h o w ev e r ,

tha t the se a re c ross -sec t iona l in na tu re , l eav ing the que s t ion w heth er fear o f m ove-

ment / ( re ) in ju ry i s secondary to the exper i ence o f low back pa in , o r tha t i t i s one

o f th e d e t e rm i n an t s o f b eco m i n g a ch ro n ic p a i n p a t ien t . R o l an d an d M o r r i s (4 3 )

and Gamsa (51) , fo r example , have sugges ted tha t emot iona l d i s t res s in pa in pa-

t ien t s is mo re l ik e ly t o b e a co n s eq u en ce , r a t h e r t h an an an t eced en t o f th e ch ro n i c

p a i n p ro b l em. In a r ecen t p ro s p ec t i v e s t u d y , K l en e rman e t a l (1 1 ) fo u n d t h e o p -

p o s i t e t o b e t r u e . T h ey co l l ec t ed b o t h p s y ch o l o g i ca l an d b i o med i ca l meas u re s f ro m

a s am p l e o f 3 00 acu t e l o w b ack p a i n p a t i en ts w i t hi n o n e w eek o f p r e s en t a ti o n , an d

a t 2 mo n t h s , a s to p r ed i c t 1 2 -mo n t h o u t co me . T h e d a t a s h o w ed t h a t s u b j ec t s w h o

h ad n o t r ec o v e red b y 2 mo n t h s (7 .3 % ) b ecam e ch ro n i c lo w b ack p a i n p a t i en t s.

M o reo v e r , f ea r o f p a i n t u rn ed o u t t o b e o n e o f t h e m o s t p o w er fu l p r ed i c t o r s o f

chron ic i ty . Th i s recen t s tudy , as wel l as the s tudy o f Bur ton e t a l (4 7 ) s u p p o r t t h e

cogn i t ive-behav io ra l mo del o u t l ined in F ig . 2 , suggest ing tha t psycho log ica l var i ab les

can ac t b o t h a s an t eced en t s an d co n s eq u en ces , r e i n fo rc i n g t h e p a i n p ro b l em i n a

co m p l ex ch a in o f ev en t s w i th f eed b ac k l o o p s.



F e a r a n d P a i n i s a b i li t y 49

n j u r y

o i l i l y I

D is u s e I Recovery

/ D e p r e ~ l ~ _ ~ . _ l l

voidance PeJnful expeden oes Confron ta lJon

+ / -

C , 4 ~ l T o p h l z l n g

]F ig ,2 . C o g n i tiv e - b e h a v io r a lo d e l f fe a ro f m o v e m e n t/ r e )in ju r y .

Fea r o f mo v em en t / r e ) i n ju ry m ay a ls o in f l uen ce p a t t e rn s o f p e r fo rm an ce o f

w ork ers wi th low ba ck pa in in an oc cup at iona l se t t ing . Cl in ic ians a re o f t e n re -

q u es t ed t o mak e j u d g men t s ab o u t t h e p r e s en t an d fu t u re fu n c t i o n a l cap ac i t y o f

p a t i en t s o n t h e b as i s o f d y n amo m et ry . T h e a s s u mp t i o n h e reb y is t h a t l u mb ar i so k -

i n e t ic ) d y n am o m et ry p ro v i d es o b j ec t iv e an d u n b i a s ed m eas u re s an d t h a t i t c an

quan t i fy maximal func t iona l capac i ty . Menard

e t a l

52) , fo r example , found a d i f -

f e r en ce i n t h e p a t t e rn o f d y n amo m et ry i n tw o g ro u p s o f lo w b ack p a i n p a t i en t s

w ho d i f fe red on ly in the p rop ens i ty o f abno rm al i llness behav io r as ind ica ted by

t h e W ad d e l l s co re ) , an d p ro p o s ed t h a t f ea r o f p a i n o f m o v em en t mi g h t b e o n e o f

the poss ib le exp lana t ions . The p lausab i l i ty o f th i s exp lana t ion i s co r robora ted by

ear l i e r s tud ies 29 , 36) in which a re l a tion be twe en fear o f m ovem ent / re ) in ju ry

an d b eh av i o ra l p e r fo rman ce i s d emo n s t r a t ed . T h i s mean s t h a t a v a l i d a s s e s s men t

o f fu n c t i o n a l cap ac i t y can n o t b e ca r r ied o u t w i t h o u t co n t ro ll in g fo r f ea r - av o id an ce

bel iefs .

In o ccup at iona l reh ab i l it a t ion , ear ly iden t if i ca tion o f ca tas troph iz ing and fear

o f mo v e m en t / r e ) i n ju ry ap p ea r s t o b e i m p o r t an t i n p rev en t in g ch ro n i c b ack d i s ab i l-

i t y . T h e T SK -D V h as t h e p o t en t i a l t o i d en t i fy a s u b g ro u p o f CL BP p a t i en t s w h o s e

d i sab i l i ty i s main ly de te rmined by the spec i f i c fear o f movement / re ) in ju ry and no t

by cur ren t pa in in tens i ty , the under ly ing o rgan ic pa tho logy , o r noc ieep t ion . For th i s

subgroup , a spec i f i c t rea tment migh t be app l i ed . Al though cogn i t ive-percep tua l fac-

to rs, and ca tas t roph iz ing in par t i cu la r , a re as soc ia ted wi th fear o f m ove m ent , d i -

dac t i c l ec tu res , educa t ion , o r ra t iona l a rgument wi l l no t be as e f fec t ive as more

beha v iora l fo rms o f in te rven t ion . A s Ba ndu ra 53) po in t s ou t, symbo l ic ev idence is

no t near ly as c red ib le as f i r s t -hand ev idence . For a fear fu l pa t i en t , i t i s fa r more

conv inc ing to ac tua l ly see h im/herse l f behav ing d i f fe ren t ly than i t i s to be to ld tha t

he / she i s capab le o f behav ing d i f fe ren t ly . For ind iv idua l s su f fe r ing f rom phobias ,

g r ad ed ex p o s u re t o t h e f ea r ed s t i mu l u s h as p ro v en t o b e a mo s t e f f ec ti v e t r ea t men t

5 4 ) . Co n s eq u en t l y , f o r t h i s CL BP s u b g ro u p , a mo re s y s t ema t i c ap p l i ca t i o n o f

g rad ed ex p o s u re t o m o v em en t , s u ch a s d e s c r i b ed b y Fo rd y ce e t a l 5) and L ind-



25 0 Vlaeyen Kole -Sn ijders Rot teveel Ru es ink an d H euts

str6m e t a l . (55), is warranted. The movements that are chosen for such an exposure

can best be matched with the work-related activities that are needed to resume

the job responsibilities after the sick leave period. Randomized prospective re-

search studies including cost-effectiveness analyses demonstrating the impact of

such a customized approach are likely to be promising, and badly needed. The

available knowledge gained both in the predictors of disability and in developing

behavioral rehabilitation programs should be applied to the field of secondary pre-

vention (56). Waiting until pain problems have fully developed into chronic and

almost irreversable situations is ethically and economical ly unjustifiable.

ACKNOWLEDGMENTS

The authors wish to thank the staff of the department of Pain Rehabilitation

and Rheumatology of the Lucas Foundation for Rehabilitation, Hoensbroek, who

contributed considerably to the clinical management of the patients included in this

study. We also wish to acknowledge the assitance of Nienke Haga of the Rehabili-

tation Center Blixembosch at Eindhoven, Robert Miihlig of the De Wever Hos-

pital at Heeden, and Huub Vonken and Wil Sillen of the outpatient clinic of the

Lucas Foundation for Rehabilitation for the referrals of patients that were included

in the second study. Thanks are also extended to Arnoud Arntz and Wip Bakx for

their advice at various stages of the study, and to Geert Crombez, Jolanda van

Haastregt, and an anonymous reviewer for their useful comments on an earlier

version of this article. This research was partly supported by Grant OG 91-088 of

the Dutch Insurance Council.

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