R e s e a r c h A r t i c l e C o m p a r is o n o f G o n io m e t r ic M e a s u r e m e n t R e l ia b il it y o f H ip Jo in t F l e x io n a n d P r o x im a l In t e r p h a l a n g e a l Jo in t F l e x io n in H e a l t h y A d u l t s SU M M A R Y : B a ck g ro u n d F o r m a n y reasons p h ysio th era p ists m easure jo in t range o f m otion o f th e ir patients. There are u su a lly variations in m ea su rem en t values o f each m otion w hen m easured eith er by the sam e p e rso n o r b y different observers. A lso reliability stu d ies ha ve resulted in varying levels o f reliability coefficients. The p u rp o se o f this study w as to com pare the g o n io m etric m e a su re m en t reliability o f a co m p le x jo in t represented b y the hip jo in t a n d a sim ple j o in t represented by p ro x im a l interp h a la n g ea l (P IP ) fle x io n m o tio n s a n d to a ssess w h eth er the tw o jo in t m o tio n s co u ld be eq u a lly reliably m ea su red b y the sam e p e rso n u n d er the sa m e test a n d retest conditions. M e th o d T hirty-three h ea lth y su b jects betw een the a g es o f 23 a n d 34 y e a rs p a rticip a te d . In order to a ssess the repeatability o f m easurem ents in the tw o selec ted j o in t m otions, the r. level o f each j o i n t m e a su re m en t was d eterm in e d a n d th eir g o n io m etric m e a su re m en t reliability com pared. R e su lt R esu lts w ere b a sed on d ata co llec te d by m ea su rin g the fle x io n range o f m o tio n o f rig h t h ip s a n d rig h t m id d le fin g e r P IP jo in ts in n o rm a l adults. S ta tistica l a n a lyses in d ica ted th a t there were sig n ifica n t d ifferences betw een go n io m etric m e a su re m en t reliability in hip a n d P IP fle x io n m otions. C on clu sion Two jo in ts w ere gon io m etrica lly m ea su red b y the sa m e tester u n d er the sam e test c o n ­ dition. R elia b ility m easurem ents results w ere com pared in thirty-three adults. B a se d on the study, the researcher c o n c lu d e d th a t the g o n io m etric m ea su rem en t o f hip fle x io n m otion is m ore variable than th a t o f P IP fle x io n m otion. OKEKE H, MA, MCSP, PT Physical Therapy Department, Kuwait University K E Y W O R D S: JO IN T -M E A SU R E M E N T -R E L IA B ILITY , H IP -JO INT, PIP-JO IN T, G O N IO M ETRY. INTRODUCTION Joint motion m easurem ent is used as part of techniques for arriving at diagno­ sis, assessing progress o f treatm ent, clinical estim ation o f perm anent disabil­ ities as well as providing records in future com parison (Cole & Tobis, 1982). The im portance o f jo in t m easurem ent in legal determ ination o f disability and provision o f research data cannot be underestim ated (Gajdosik & Bohannor, 1987). Clinicians measure range o f mo­ tions o f their patients not only to deter­ mine baseline lim itations before actual treatm ent com m ences, but also to assess CORRESPONDENCE: HA Okeke Faculty o f Allied Health Sciences Physical Therapy D epartm ent School o f Allied Health Professions K uwait University P O Box 31470 90805 - Sulaibikhat KUWAIT Tel: (965) 482-4325 (H) (965) 483-3706 (W) Fax: (065) 483-0937 E-mail: Okeke@hsc.kuniv.edu.kw the efficacy o f intervention employed. Many different devices have been used generally for range o f motion m easure­ ments such as estim ation (Som ers et al, 1997), photography (Miller, 1985), xero­ graphy (Regenos & Chyatle, 1970). Also specific jo in t m easurem ent devices and methods have been used to assess range o f motion o f specific joints (Nwaobi, 1987). H am ilton and L achenbruch, (1969) com pared different types o f goniom eters - specific dorsal, pendulum and univer­ sal for assessm ent o f finger jo in t angles and found that the three goniom etric types were equally reliable. Rothstein et al, (1983) found no difference in relia­ bility o f large metal, large plastic and small universal goniometers. Goniometer is by for the most popular device for measuring jo in t range and com m only used goniometer by many clinicians is the Universal Goniom eter (UG) whose vali­ dity and reliability have been accepted. For this study, a small metal universal goniom eter calibrated in degrees was used. M iller (1985) reported norm al values o f range of motion o f major joints o f the body from ten referenced-sources. The values for the elbow flexion ranged from 135°-160° (m ean 146.8°), hip flexion from 110°-130° (mean 119.7°) and hip abduction from 45°-55° (mean 46.1°). The standard deviations o f measurement errors for the three m otions were elbow 8.7°, hip flexion 7.6° and hip abduction 3.9°. Thus, there was evidence o f levels o f variations in m easurem ent errors in each o f the three jo in t motions. Those variations existed not only in the normal values o f each motion in the ten dif­ ferent studies but also in the level of dif­ ferences between one jo in t motion and the other. A lthough most joints o f the body have been shown both in patients and healthy subjects as being capable of being reli­ ably m easured, reliability studies have resulted in varying levels o f reliability coefficient (Babyar, 1996; Youdas et al, 1994). The purpose o f this study, there­ fore, was (1) to determ ine whether some jo in t motions could be more reliably measured than others, in particular (1.1) to assess the goniom etric m easurem ent re lia b ility o f the hip jo in t and p ro x i­ mal interphalangeal (PIP) jo in t flexion 24 SA J o u r n a l o f Ph y sio t h e r a p y 1999 V o l 55 No 4 R ep ro du ce d by S ab in et G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r (d at ed 2 01 3. ) mailto:Okeke@hsc.kuniv.edu.kw m otions in normal subjects and (1.2) to determ ine whether the two jo int motions could be measured with high levels of reliability by the same tester under the same test conditions using the UG. The study was considered important because as much as goniom etric relia­ bility o f joint measurements enable clini­ cians to detect variations in jo int range, variations may be consistently more in som e joints than in others. Prior know ­ ledge o f range o f motion characteristics o f jo int types would enable judicious decisions to be made regarding the nature o f interventions. The choice o f hip and PIP joints was based on the understand­ ing that the hip was more complex a jo in t than PIP joint. Flexion motions in the two join ts run through identical excursion o f 180°-0° using that system o f notation so that any difference in reli­ ability m easurements under the same type o f control in healthy subjects must not be due to m easurem ent errors. The researcher hypothesized that there was no difference between goniometric range o f motion m easurem ent reliability in the hip jo in t flexion and goniom etric range o f m otion m easurem ent reliability in the PIP jo in t flexion motion. Earlier studies based on goniometric jo in t m easurements repeated by the same person or by different observers found high levels o f goniom etric reliability in measurem ents. However, H ellebrandt et al, (1948) did not find wrist flexion or shoulder abduction m easurem ents reli­ able when repeatedly m easured. D eter­ mination o f goniometric reliability o f hip m easurem ents (G ajdosik et al, 1985) and that o f finger joints (Serup, 1983) have also been conducted. However, the studies encom passed only tester, instru­ ment and condition variables. Gajdosik & Bohannor, (1987) reviewed literature on reliability and validity o f goniom etric measurem ents o f extremities. Based on the conclusions o f earlier studies (Gajdo­ sik et al, 1985) they concluded that hip motions could be reliably m easured if m easurem ent procedures were properly controlled. The implication is that varia­ bility in range o f motion m easurem ent reliability could be eliminated in any joint provided the same procedural control was observed no matter the type o f joint. METHOD Subjects: Thirty-three healthy volunteer physical therapists, p hysical therapy interns and final year physical therapy students were selected from the P hysical T herapy Department o f University o f Nigeria Teaching Hospital, Enugu, N igeria to participate in the study. The participants, eighteen women and fifteen men were screened for hand preference and history o f injury or illness that m ight affect range o f motions o f the joints o f interest. They were also told to report any patho­ logy which m ight affect the range o f motion between the initial m easurem ent and subsequent measurements. Written informed consent was obtained from all the participants before participation in the study. D em ographic information o f the subjects are sum m arised in Table 1. TABLE 1: CHARACTERISTICS OF SUBJECTS Number of subjects 33 Female 18 Male 15 Age(years) X 28.1 SD 3.4 Range 23-34 Instrument A small metal half-cycle protractor scales- type UG was used to measure the range o f m otions o f the joints o f interest in degrees. The stationary and movable arms were each 14.5 cm in length from the axis (Fig. 1). The choice o f UG was determ ined by its obvious advantages including that it could be used to m ea­ sure many types and sizes o f joints. It is considered to be com m only used clini­ cally being the sim plest, most portable and easily available. Moreover, UG hav­ ing been established as an instrum ent for m easurem ent o f range o f m otion in degrees, has frequently been used as criterion m easure for determ ining the v alidity o f new instrum ents designed for m easurem ent o f jo in t range. Procedure The procedure for m easurem ent o f hip flexion motion was a m odification on procedures em ployed by earlier w ork­ ers. The subject was supine with hip and knee o f the side to be m easured in exten­ sion on a flat surface. To determ ine the axis o f the right hip, a line joining the right anterior superior iliac spine and sym physis pubis was bisected by a line running laterally to the right greater tro­ chanter. The axis o f the goniom eter was then placed on the external point corre­ sponding to the axis o f the hip joint. The stationary arm was aligned with the lat­ eral side o f the pelvis while the m ovable arm was placed lateral to the long axis o f the femur. The subject was then asked to bend the left hip and knee as far as they could go. The m ovable arm o f the goniom eter was held against the thigh with which it moved as the right leg was being raised. At the limit o f flexion o f the hip, the reading on the goniom eter was recorded. To m easure the PIP jo in t w hose fle­ xion m otion is functionally dependent on the influence o f adjacent proximal and distal joints to it, a special stabilizing device was used to im m obilize other FIGURE 1: COMPARISON OF HIP AND PIP FLEXION MEASUREMENT RELIABILITY SA J o u r n a l o f Ph y s io t h e r a p y 1999 V o l 55 No 4 25 R ep ro du ce d by S ab in et G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r (d at ed 2 01 3. ) FIGURE 2: COMPARISON OF HIP AND PIP FLEXION MEASUREMENT RELIABILITY nearby jo in t movem ents from the wrist, hand and finger other than the desired flexion motion o f PIP jo int o f the right middle finger (Fig. 2). With the subject sitting, the right forearm was supinated and with the stabilizing device secured, the axis o f the goniom eter was placed at the ulnar side o f the axis o f rotation of the joint. The stationary arm was placed to run along the proxim al bone and m ov­ able arm along the digital bone. The subject was asked to bend the finger and at its limit o f flexion, the goniom eter reading was taken. Com m on to proce­ dures in the two join ts were: a) The range o f motions was active b )T h e two motions were carried out against gravity. c) Each m easurem ent was repeated three tim es and the average found and recorded as the score for that measure­ m ent session. d) Positioning was rigidly standardized during measurement. e) The 0 °-180° system o f notation was used. All m easurem ent data was collected betw een the second w eek o f July and second w eek o f A ugust, 1997. M easure­ m ent sequence was alternated between the two joints. Data Analysis Obtained data was analyzed by descrip­ tive statistical procedures relating to mean, standard deviation and coefficient of variation. Pearson product-m om ent correlation coefficient was em ployed to analyse the reliability o f measurements o f the tw o jo in ts flex io n m otions. Finally, analysis o f variance (ANOVA) was used to test the hypothesis that there was no difference betw een the goniom etric range o f m otion m easure­ m ent reliability in the hip jo in t flexion and goniom etric range o f m otion m ea­ surem en t reliab ility in the PIP jo in t flexion motion. RESULTS The average o f three m easurem ents was com puted to represent the score for each session. Table 2 sum m arizes the high­ lights o f d e sc rip tiv e statistical data obtained from the test and the retest sessions for each joint. To com pare the test and retest m ea­ surem ents o f each o f the tw o joints, P earson P ro d u ct-m o m en t correlation c o efficien t fo r in tratester reliability y ielded r=0.93 fo r h ip flexion and r=0.99 for PIP jo in t flexion. Coefficient o f variation (CV) for hip was 11.8% and for PIP 8.8%. Finally ANOVA indi­ cated that there was a difference between goniom etric m easurem ent reliability in hip and PIP flexion motions. The results suggested that PIP joint flexion m otion was m ore reliably m ea­ sured than the hip jo in t flexion motion in normal adults. DISCUSSION The study was designed to determ ine the com parative reliab ility o f goniom etric m easurem ents o f a com plex jo int - the hip, and a sim ple hinge jo in t - PIP joint flexion motions. The results obtained from statistical analysis allow for rejec­ tion o f null hypothesis. The researcher obtained high correla­ tion coefficients for both hip and PIP jo in t flexion m otions viz r=0.93 and r=0.99 (p < 0.001) respectively. Although the design of the study was not intended prim arily to test m easurem ent precision, the high correlation values in each jo int had two im plications. Firstly, the coef­ ficient values form part o f the data on which com parisons o f the two jo in t m otions could be based. Secondly, high correlation coefficient values gave fur­ ther assurance that m easurem ent error was m inim ized indicating that the com ­ ponents o f the test e n v iro n m en t and m ethods w ere properly controlled. The C oefficient o f Variation o f hip flexion m otion was higher than that o f PIP flexion motion. The differences in the coefficient o f variation indicated the relative variation o f hip flexion motion 26 SA J o u r n a l o f Physiotherapy 1999 V o l 55 No 4 R ep ro du ce d by S ab in et G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r (d at ed 2 01 3. ) TABLE 2: GONIOMETRIC MEASUREMENT IN THE HIP AND PIP ACTIVE FLEXION MOTION HIP MEAN SD Measurement 1 105.76 12.76 Measurement 2 104.38 12.02 PIP Measurement 1 117.76 10.39 Measurement 2 118.48 10.49 and PIP flexion motion measurements. These differences helped to rem ove any doubt that might have existed in inter­ pretation o f the differences in their m eans and standard deviations. Finally, based on ANOVA conducted on the two jo in t m easurem ent data, the hip jo int flexion motion was significantly less reliably m easured than that o f PIP. T his study co n trasted w ith other reported studies relating to goniometric reliability m easurem ents done in the past. The use o f present methodology to com pare the reliability o f goniom etric measurem ents o f two anatom ically dis­ similar joints has not previously appeared in the literature. The shoulder and hip as com plex joints have three degrees free­ dom o f movement. In contrast, the el­ bow, knee and PIP joints are classified as hinge joints with one degree freedom o f movement. Difficulties in determining m easu rem en t relia b ility o f com plex join ts have been recognized (Gajdosik & Bohannor, 1987). M any reasons have been suggested for difficulty in measure­ ment o f com plex joints. These include presen ce o f two jo in t m uscles whose actions varied according to situations (Rothstein et al, 1983), bulk o f muscles around them w hich often lim ited full m ovem ent excursion and concurrent m ovem ent o f adjacent joints (Gajdosik et al, 1985). However, Boone et al, (1978) com ­ pared goniom etric reliability o f three joints o f the upper extrem ity with three join ts o f low er extremity. Their findings implied, am ongst others, that two com ­ plex joints - shoulder and hip motions were more reliably m easured (r=0.96 and 0.76 respectively) than those o f two sim ple hinge joints - elbow and knee (r= 0.94 and 0.74 respectively). The results may have been influenced by the fact that the researchers focused atten­ tion on com parison between the upper and low er extrem ity joints rather than with the types and behaviors o f indivi­ dual joints m aking up the groups. Ekstrand et al, (1982) in a study to determ ine the reliability o f goniometric measurements o f the joints o f the lower extrem ity found m easurem ent o f hip joint flexion more variable than that of knee jo int flexion. Rothstein et al, (1983) assessed intratester reliability o f gonio­ metric m easurem ents o f passive elbow and knee jo int flexions using three types of goniometers. Pearson Product moment correlation coefficient values in the two joints were high and showed r o f 0.96 and r=0.98 for elbow and knee respec­ tively. The findings o f the above two stu­ dies were in line with those o f the pre­ sent study. Also, Miller, (1985) reported the raw data o f hip flexion m easurem ents from ten referenced-sources and based on the data, the present researcher calculated the CV o f flexion motions for the shoul­ der and hip as com plex joints as well as for the elbow and knee as simple hinge joints. The results showed more varia­ bility in the shoulder and hip (CV 18.1% and 7.3% respectively) com pared with variability in the elbow and knee (CV 5.2% and 5.3% respectively). These find­ ings derived from M iller’s report were also in agreem ent with the outcom e of the present study. The choice o f hip flexion motion has been considered apt by the researcher because o f com m on occurrences o f hip flexion contractures in neurologic, ortho­ paedic and other situations o f inactivity as often seen in the elderly population. The need for clinicians to appreciate the limits o f variability in hip flexion motion cannot, therefore, be overstressed. Little has been reported on P IP jo in t of the hand. N everthless, it is an important functional jo int o f the hand whose pre­ dictive range clinicians ought to be con­ versant with. O edem a and pain tend to place the PIP in flexion w hich often makes flexion deform ity o f the jo in t a very com m on feature. Its interm ediate position in a segm ented lever (finger) makes it possible for objects to be firmly gripped. W hen the range o f m otion of P IP jo in t is limited such as in swan neck deformity, boutonniere deform ity or as a result o f adhesion o f soft tissues around the jo in t following trauma, smooth and relay buckling o f the finger into the palm becom es com prom ised and crippling. A ctive range o f motion of joints is prim arily related to the degree to which ligam ents and muscles function. In case o f hip and PIP joints, superim position o f pathologies make their functions diffi­ cult to assess. Understanding the pecu­ liarities o f m easurem ent behaviours o f each jo in t o f the body, is important, because the clinician is in a position to discern betw een restrictions im posed by pathology and lim itations due to inhe­ rent idiosyncracy of the joint. However, this study should serve as a spring-board for further studies to determ ine w hether such differences in reliability m easure­ m ents o f many other anatom ically dis­ sim ilar join ts exist. Also many more subjects both patients and healthy sub­ jects under varying environm ental con­ ditions should be involved. CONCLUSION Two joints were goniom etrically m ea­ sured by the same tester under the same test condition. Reliability measurements results w ere com pared in 33 healthy adults. Based on the study, the researcher concluded that the goniom etric m ea­ surem ent o f hip flexion motion is more variable than that o f the PIP flexion motion. In research and clinical settings w here reliable m easurem ents are essen­ tial, this study provides further under­ standing o f goniom etric m easurements applied to two particular joints by a sin­ gle therapist. The results can only be generalized to healthy and relatively young subjects. SA J o u r n a l o f Ph y sio t h e r a p y 1999 V o l 55 No 4 27 R ep ro du ce d by S ab in et G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r (d at ed 2 01 3. ) REFERENCES 1. B ab yar S R 1996 R elia b ility o f student p h y sic a l th e ra p ists in p e r fo r m in g tw o te c h ­ n iq u e s fo r g o n io m e tr ic m easu rem en t o f p as­ siv e sh o u ld er p o sitio n in the horizontal plane. J o u r n a l o f P h y s i c a l T h e r a p y E d u c a tio n 1 0 :8 5 -8 9 2. B o o n e D C , A z e n S P 1979 N orm al range o f m otion o f jo in t in m a le su b jects. J o u r n a l o f B o n e a n d J o in t S u rg e r y 6 1: 1 5 6 - 15 9 3. C o le T M , T ob is JS 198 2 M ea su rem en t o f m u sc u lo sk e le ta l fu n ctio n . In K ottke FJ, S till­ w ell G K , Lehann JF (ed s). K r u s e n ’s H a n d b o o k o f P h y s i c a l M e d ic in e a n d R e h a b ilita tio n . P h ila d e lp h ia . W .B . Saunders C o ., P hilad elp h ia 4. Ekstrand J, W ik to r sso n M , O berg B 1892 L o w e r ex trem ity g o n io m e tr ic m easurem ents: A study to d eterm in e their reliability. A r c h iv e s o f P h y s ic a l M e d ic in e a n d R e h a b ilita tio n 6 3 :1 7 1 -1 7 5 5. G ajdosik R L, B o h a n n o n R W 1 987 C lin ica l m ea su rem en t o f ran ge o f m otion: R e v ie w o f g o n io m e tr y em p h a siz in g relia b ility and v a li­ dity. P h y s ic a l T h e r a p y 6 7 :1 8 6 7 -1 8 7 2 6 . G a jd o sik R L , S im p s o n R, S m ith R, D a n tio n y R 198 5 P e lv ic tilt: Intratester relia­ b ility o f m easu rin g the standing p o sitio n and range o f m o tio n . P h y s ic a l T h e ra p y 6 5 :1 6 9 - 174 7 . H a m ilto n G F, L a c h e n b r u c h PA 1 969 R elia b ility o f g o n io m e te r s in a ss e s s in g finger jo in t a n g le. P h y s ic a l T h e ra p y 4 9 : 4 6 5 -4 6 9 8. H ellebrandt FA, D u vall E N , M oore M L 1948 T h e m easu rem en t o f jo in t m o tio n part III: R elia b ility o f g o n iom etry. P h y s ic a l T h e ra p y R e v ie w 2 9 :3 0 2 -3 0 7 9 . M iller PJ 1 985 A s se s s m e n t o f jo in t m o tio n . In R oth stein (e d ) M ea su rem en t in P h y sica l T herapy. C hurchill L iv in g s to n e , N e w York 10. N w a o b i O M 1987 G o n io m e te r sy ste m for m easu rin g bilateral hip ab d u ction in cerebral palsy: S u g g e stio n from the field . P h y s ic a l T h e ra p y 6 7 : 9 5 3 -9 5 4 11. R e g e n o s E M , C h y a tle S B 1970 Join t range and d e fo r m ity re c o r d e d b y x ero g ra p h y . P h y s ic a l T h e ra p y 5 0 :1 9 0 12. R oth stein JM , M ille r PJ, R o ettg e r R F 1983 E lb o w and k n e e m e a su r e m e n ts. P h y s ic a l T h e r a p y 6 3 :1 6 1 1 -1 6 1 5 13. Serup J 19 8 3 M ea su rem en t o f contractures o f d ig its in sy s te m ic sc le r o sis. D e r m a to lo g ia 1 6 7 :2 5 0 -2 5 5 14. S o m e rs D L , H a n so n JA , K ed ziersk i CM , N e sto r K L , Q u in liv a n K Y 1997 T h e in flu en ce o f e x p e r ie n c e on the relia b ility o f g o n io m e tric and v isu a l m ea su rem en t o f fo r e fo o t p osition . J o u r n a l o f O r t h o p a e d i c S p o r t s P h y s i c a l T h e r a p y 25: 1 9 2 -3 0 2 15. Y oudas JW, C arey JR, Garrett T R , Sum an VJ 1 994 R e lia b ility o f g o n io m e tr ic m easu re­ m en ts o f a c tiv e arm e le v a tio n in the scapular p lane o b ta in ed in a c lin ic a l se ttin g . A r c h iv e s o f P h y s i c a l M e d ic in e a n d R e h a b ilita tio n 75: 1 1 3 7 -1 1 4 4 THE SOUTH AFRICAN SOCIETY OF PHYSIOTHERAPY would like to congratulate Prof. Sielie Eales on her appointment as Editor of the S.A. Journal of Physiotherapy. We know she will bring a wealth of experience in various sectors, to the position. ♦♦♦ ♦♦♦ ♦♦♦ We would also like to thank Prof. Muriel Goodman, outgoing Editor, for her achievements since being at the helm and wish her much peace and happiness in her retirement. 28 SA J o u r n a l o f Ph y s io t h e r a p y 1999 V o l 55 No 4 R ep ro du ce d by S ab in et G at ew ay u nd er li ce nc e gr an te d by th e P ub lis he r (d at ed 2 01 3. )