Interest of the Ergo-Kit(®) for the clinical practice of the occupational physician. A study of 149 patients recruited in a rehabilitation program

Original article

Interest of the Ergo-Kit

¹

for the clinical practice of the occupational physician. A study of 149 patients recruited in a rehabilitation program

J. Caron

^a,c,

*, Y. Ronzi

^a,b

, J. Bodin

^a

, I. Richard

^a,b

, L. Bontoux

^a,b

, Y. Roquelaure

^a,c

, A. Petit

^a,c

aLUNAMuniversite´,universite´ d’Angers,laboratoired’ergonomieetd’e´pide´miologieensante´ autravail(LEEST),faculte´ deme´decined’Angers, rueHaute-de-Recule´e,49045Angerscedex01,France

bDe´partementdeme´decinephysiqueetdere´adaptation,CHUd’Angers,28,ruedesCapucins,49103Angerscedex02,France

cCentredeconsultationsdepathologieprofessionnelle,CHUd’Angers,me´decineE,4,rueLarrey,49933Angerscedex9,France

1. Introduction

Workcapacityevaluation (WCE)is dedicatedtoassesswork capacities of a person to perform a job. The WCE describes, analyzestasksaswellasworkplacedemands(WPD)accordingto differentstrategiesanddetermineshowtheworkercanfaceupto them [1]. Itis mostoften conductedin PhysicalMedicine and RehabilitationCenters(PM&R).Itcontributestotherehabilitation program organization, the return-to-work (RTW) prognosis, its implementation (safe and sustainable), even whennecessary it maycontribute tocareer change [2] and canhelp determinate eventualrightstoworkers’compensation[3,4].TherearetwoWCE categories:evaluation in theworkplaceenvironmentand Func- tionalCapacityEvaluation(FCE) [5].There arejob-specificFCEs thatincludereal-lifesituationsbysimulatingworktasks,aswellas generalFCEs.

Ergo-Kit¹(EK)marketedby‘‘Ergocontrol’’(Netherlands)isa validated tool [6,7] to conduct FCEs and WPD evaluations. It consistsinabatteryof55standardizedphysicaltestsmeasuringa worker’smaximumcapacitiesaccordingtocertainWPDssuchas manual handling of loads (MHL), manual dexterity, ability to maintaindemandingpostures,etc.Thisassessmentisconductedin a healthcareenvironmentandtherecommendationgivenafter- wardsisapresumptiononthecompatibilitybetweentheperson’s functionalstatusandgeneraljobtasks.Arecommendationonthe real-lifecompatibilitycan onlybeexpressedafterconductinga WCEintheworkplace[8,9].

In the literature, FCEperformance is influenced by physical factors(i.e.age,sex),typeanddurationofthedisability,presence ofassociatedpainanditsintensity,aswellaspsychologicalfactors (i.e.perceptionofthedisability,anxiety-depression,self-assess- mentoffunctionalcapacities)[10,11].

TheEK,marketedinTheNetherlandssince1993,isavailablein threeotherEuropeancountries(Belgium,LuxemburgandFrance).

Theuseofthis toolrequiresaspecifictrainingdeliveredbythe ARTICLE INFO

Articlehistory:

Received30October2014 Accepted12August2015

Keywords:

Functionalcapacityevaluation Ergo-Kit

Physicalworkload Workdemands Returntowork

ABSTRACT

Objective:Functionalcapacityevaluationiscommonlyusedtoassesstheabilitiesofpatientstoperform sometasks.Ergo-Kit¹isavalidatedtoolassessingbothfunctionalcapacitiesofpatientsandworkplace demands.TheobjectiveofthisstudywastoevaluatetherelevanceoftheErgo-Kit¹dataforoccupational physiciansduringthereturn-to-workprocess.

Methods: A retrospective and monocenter study was conducted on all patients included in a rehabilitation program and assessedwith theErgo-Kit¹ toolbetween 2005and 2014.Workplace demandsandpatients’functionalcapacitieswereevaluatedandconfronted.Self-beliefsandperceived disabilitywerealsoassessedandcomparedtothefunctionalcapacityevaluation.

Results:Onehundredandforty-nineworking-agepatients(85men,64women;3912years)suffering from musculoskeletal disorders or other diseases wereincluded. Main causes of mismatch between workplacedemandsandfunctionalcapacitiesweremanualhandlingofloads,postureswitharmsawayfrom thebodyandrepetitivemotionsatwork;sittingposturewascorrelatedwithalesserphysicalworkload;and OswestryscorewascorrelatedwithfunctionalcapacitiesevaluatedbytheErgo-Kit¹.

Conclusion:Ergo-Kit¹isarelevanttooltoassessthemultidimensionalaspectsofworkplacedemands andfunctionalcapacities.Itcouldbeveryhelpfulforoccupationalphysicianstomanagereturn-to-work.

ß2015ElsevierMassonSAS.Allrightsreserved.

* Correspondingauthor.Tel.:+33664186741.

E-mailaddress:[email protected](J.Caron).

Availableonlineat

ScienceDirect

www.sciencedirect.com

http://dx.doi.org/10.1016/j.rehab.2015.08.002

1877-0657/ß2015ElsevierMassonSAS.Allrightsreserved.

companymanufacturing the EK. To our knowledge, no French studyhasevaluatedtheresultsofFCEsusingtheEK.

The RTW issue consists in evaluating a worker’s functional capacities(FC)inordertoreturntoworktothesamepositionor anotheronewithnorisktotheworker’shealth.Themainobjective ofthisstudywastoconductasynthesisofallelementsyieldedby theEK useful to healthcare professionals involved in the RTW process,especiallytheoccupational physician(OP),about work conditionscompatiblewithasafeRTW.Thesecondobjectivewas toevaluateassociationsbetweenself-assesseddisabilityindicators andFCEresults,whichcanguidethedecisionsoftheOP.

2. Material

Thisdescriptive,retrospectivemonocenterstudywasconduc- tedonallthemedicalchartsofpatientsevaluatedinthePM&R department of the Angers University Hospital in France from March 2005 to April 2014. Over this time period, 209 EK evaluationswereconductedforatotalof185patients,including 149patientsinRTWorstay-at-worksituations(personswithjob difficultiesand/oron sickleave orout ofa job oron disability leave).Patientswereseeneitherasinpatientsoroutpatientsinthe AdultorPediatricunitsofthePM&Rdepartment.

Studyinclusioncriteriawere:beingbetween15and65yearsof age, having one of the following work statuses: employee, employerwitha salary,independent worker,apprentice,unem- ployedworkerorworkerondisabilityleave,beinginRTWorstay- at-worksituation,havingsignedthestudy’sparticipationconsent formaswellasparentalconsentformforminors.Exclusioncriteria were:beinga student,retiredorwithanunknownworkstatus, havinga contraindication toperformtheEK assessment (usual contraindicationsrelatedtointensiveefforts,seeAppendix1).

The various EK tests follow a standardized protocol[12]. A French adaptation of this protocol (Ergo-Kit¹ manual) was conductedby thePM&Rdepartmentandis usedasa reference andbasisfortheEKtrainingsoftheFrench-speakingteams;this protocolhasnotyetbeenvalidated.TwotypesofEKevaluations arepossible:

half-dayassessment:pre-assessmentinterviewandFCE;

full-dayassessment:pre-assessmentinterview,WPDevaluation andFCE.

TheWPDevaluationisconductedinthecontextofstay-at-work conditionsandwhenpatientsareabletodescribetheirjobtasks.

However,a WPDevaluation canbenecessarywhen thepatient doesnothaveajob(tohelpguideandpromotethechoiceofanew professional orientation). The reason for conducting a WPD evaluation has to be validated by the PM&R physician who prescribedtheevaluation.

Thesetwotypesofevaluationsgenerateawritingreportusing theErgoControlsoftware.Alltheseevaluationswereconductedby threeoccupationaltherapistsfromthePM&Rdepartmenttrained toconducttheEKprotocol.

2.1. Pre-assessmentinterview

Itconsistsincollectingthefollowingelements:

sociodemographicdata:age,sex,typeofevaluationanddateof theevaluation;

medicaldata:habits(tobaccoand/oralcoholuse),historyofthe disease, diagnosis, treatment, medical history and associated disorders,collectedbytheoccupationaltherapistbasedonthe information given by the patient as well as the evaluation requestformfilledoutbyprescribingphysician;

currentsportpractice;

clinicaldata:height,weight,dominanthand,bloodpressureand heartrate;

socialandoccupationaldata:educationalattainment,numberof professionalexperienceworkyears,position,lengthofservice, beingonsickleaveornot,durationofprofessionalinactivityand self-assessmentontheabilitytowork;

self-questionnaireonfunctionaldisability:theOswestrypain&

disabilityquestionnaire[13]translatedandvalidatedinFrench [14]withtheadditionofan11thquestion(‘‘Arethereanyother houseworkorleisureactivitiesyouarenotabletoperform?’’).

TheinitialobjectiveoftheOswestrylow-backpainquestionnaire was to measure the functional impact of low-back pain on activitiesofdailyleaving[13,14].Thisscorehasahighvalidity and reliability [15]. Results are expressed in disability per- centagesoutof100andareanalyzedassuch:0–20%:minimal disability;21–40%:moderatedisability;41–60%:severedisabil- ity; 61–100%: extremely severe disability. The 11th open questionwasaddedinordertocollecteventualmissingdata.

2.2. Functionalcapacityevaluation(FCE)

FCsarequantifiedaccordingtotheDepartmentofLabor(DOL) USA system, allowing the analysis of physicalcharacteristics of occupationalactivitiesgroupedintotheDictionaryofOccupational Titles1991(DOT)[16].TheEKevaluates27functionalabilitiesofthe DOLsystem:12MHLabilitiesand15otherabilities(Appendix2).

TheFCEisentirelyperformedwiththeEK,whichincludesa Purdue Peg Board Test (neuropsychological test of manual dexterityandbimanualcoordination),aJamarmanualdynamom- eter,adynamometerplatform,acolumnwithadjustableelements andastepplatformtoconduct55physicaltests(Figs.1and2).

Eachfunctionalabilityis assessedbytheoccupationaltherapist takingintoaccountoneormoreofitsrelatedphysicaltestsand

Fig.1.Testofmanualhandlingofloads.

followingareasoningandanalyticprotocol.TheFCsbelongingto theMHLcategoryareestimatedinmaximalweight(kg)thatcanbe liftedor movedforeach time-period (infrequency)oftheDOL system(Appendix2,example:occasionallylowering7.5kg=the patientisabletoliftaloadof7.5kg,loweringfromthefloortothe waist up to 32 times a day). The other FCs are estimated in percentages of an 8-hour workday (example: sitting down 90%=thepatientisabletositdownforupto90%oftheworkday).

TheFCsarecomparedtothenormsoftheDOLsystemand the WPDswhenavailable,withinananalyticdiagram(Fig.3).Afterthe evaluation,avalidityscorefrom1to5iscalculatedcomparingthe resultsofdifferentphysicaltestsmeasuringsimilarabilities(for example:studyonthecoherenceofthecurvesforthetwoJamar dynamometerreproducibilitytests).Thisscore isabletodeter- mineifonecantakeintoaccountalltheresultsoftheFCEfora givenpatient.Thehigherthescore,thehigherthetests’validity.

2.3. Workplacedemands(WPD)evaluation

AWPD evaluationis notsystematic and dependson theEK indication.Threedetailedself-questionnairesaremailed,priorto theevaluation,tothepatient’shome:

personal information questionnaire: sociodemographic data (usefulduringthepreliminaryinterview);

‘‘work’’ questionnaire: type of workcontract, work schedule, workrate,autonomy,opportunitiesforcareerdevelopment;

‘‘workactions’’questionnaire:foreachtaskthedifferentactions aredetailed.

The WPDevaluation corresponds to evaluating thephysical constraintsrelatedtothejobduringaninterviewwiththepatient, afterthepreliminaryinterviewandbeforetheFCE.Fromthedata in the‘‘work actions’’questionnaire,a totalarduousnessindex

scoreon100iscomputedfromthearduousnessindexesofeach action. A ‘‘work abilities’’ form filled out by the occupational therapisthelpsquantifytheWPDsaccordingtotheDOLsystem.

3. Methods

WPDswerecomparedto(Table1):

MHLthresholdvaluesoftheAFNORNFX35-109normtoliftand moveloads[17];

exposuredurationsdefiningarduoussituationsandconstraining posturesfromtheSummer2003study[18];

exposure durations described as specific risk factors for musculoskeletaldisorders(MSD)oftheupperlimb[19];

DOLstandardsusedintheEKprotocol.

Thesedifferentreferenceswereextrapolatedforabilitieswith nosetthresholdvalues(Table1).

Colorareasweredefinedusingthedifferentthresholdvalues listedabove.Foragivenability(example:reachinglow),thegreen area ‘‘acceptableconstraints’’includedjobsforwhichtheWPDs were below the lowest threshold value and the red area

‘‘unacceptable constraints’’ included jobs for which the WPDs were above the highest threshold value. The yellow area

‘‘acceptable constraints under certain conditions’’ is located in betweentheredandgreenareas.

Whenpossible,WPDandFCEdatawereconfrontedinorderto obtain a presumption rate of match or mismatch between the patient’sFCsandWPDsforeachability,usingthefollowingformula:

FCE–WPD.Whentheresultwas0,apresumptionofmatchwas noted.Iftheresultswas<0,apresumptionofmismatchwasnoted.

Forexample,ifapatientpresentedFCsfor‘‘sitting’’during90%ofhis/

her workday and WPDs at 33%, the presumption of match for

‘‘sitting’’wasnoted.Conversely,ifapatienthadFCsfor‘‘stooping’’at 10%andWPDsat50%,thepresumptionofmismatchfor‘‘stooping’’

wasnoted(Fig.3).Thismethodwasusedontheentirepopulation studied,regardlessofthepathology,andalsoonthesubgroupof patientswithMSDoftheupperlimb.

Avariable‘‘WPDrelativefunctionalcapacities’’(relativeFCs) wascreatedbydividingtheFCEdatabytheWPDdata(FCE/WPD) in order to confront sick-leave related variables. Jobs without WPDs for a given ability werenot analyzed. For example, ifa patienthadFCsfor‘‘stooping’’at10%andWPDsat50%,therelative FCsfor‘‘stooping’’were20%(10/50=0.20).

A ‘‘global FCEperformance index’’, previouslyused in other studies[20,21]wascreatedinordertoconfirmthevalidityofour resultsbycomparingthemtotheonesreportedinthesestudies.

Thisindexrepresentedthesumofallabilitieswithapresumption ofmismatchforagivenpatient,itcouldrangefrom0to27.The highertheindex,thelowertheglobalperformance.

3.1. Datacollectionandstatisticalanalysis

DatacollectionfromtheEKreportsaswellasthedescriptive analysisofthesamplewereconductedwiththeMicrosoft¹Excel¹ forMac2011softwareversion14.0.0.Nonparametricstatistical tests(Fischer exacttest and,ifnecessarytheCochran-Armitage testtostudytheassociationbetweentwoqualitativevariables,the Wilcoxon–Mann Whitneytest tocompare thedistribution ofa quantitative variable according to a qualitative variable, the Spearman Rank-Order Correlation to study the correlation between two quantitative variables) were performed via the BiostaTGV website (http://marne.u707.jussieu.fr/biostatgv/) as wellastheSAS¹9.4forWindowsSoftware.Statisticaltestswere conductedforsamplesofatleast10patientsandthesignificance Fig.2.Reachingandhandlingtest.

threshold was set at 5%. Quantitative data were presented as meansandstandarddeviationsandqualitativedataasnumbers andpercentages.Thestatisticsinthisstudydidnotaccountfor missingdata.

Westudiedthefollowingvariablestoguidethedecisionofthe OP:beingon sick leave,durationof sickleave,Oswestryscore, performanceindex,feelingof‘‘beingabletowork’’,arduousness index, upper limb impairment, laterality of the upper limb impairment.Patientswithanapprenticestatuswerevoluntarily discardedfromtheWPDanalysesduetotheperiodicalnatureof their work. Unemployedworkerswho benefited froma double WPD+FCE assessment were also discarded from the analyses sincetheywerenotemployedatthetimeoftheevaluation.

Patients’ social and occupational categories were classified accordingtothe8categoriesofthe1stlevelofthenomenclaturedes professionsetcate´goriessocioprofessionnellesPCS2003 (InseePCS 2003 norms) [22] and the different sectors of activities were categorized according to the French nomenclature d’activite´s franc¸aises(NAF2008normfromInsee)[23].

3.2. Ethics

Allpatientssignedaconsentformforperformingthetestsand compiling their results in a database. For minors, a parental authorizationwascollected.Theinformationdeliveredtopatients aswellastheirauthorizationfordatacollectionforastudywere considered asaninformedand voluntaryconsent.Inregardsto nationaldataprotectionlaws,allpersonaldatawerehandledina confidentialmannerandusedexclusivelyforscientificmeans.Due to the retrospective nature of the study, no additional ethics considerationswererequested.

4. Results

Overall,92WPD+FCEcombinedevaluationsand57singleFCEs wereconducted.Themainindicationforevaluationswastheissue of stay-at-work with planned RTW(63%) and in 72% of cases, related toanaffectionof oneor bothupper limbs(47%on the dominantside,30%onthenon-dominantsideand23%bilateral).

Fig.3.ExampleofWPDandFCEanalysisdiagram(withoutmanualhandlingofloads).^*DH:dominanthand;NDH:non-dominanthand.

AlmosthalfthepatientswerereferredforMSDoftheupperlimbor thespine.Themeanvalidityscoreevaluationwas3.80.8;itwas inaveragelowerforMSDoftheupperlimbs(3.40.9),butnotfor spinalpathologies(4.20.5)(Table2).

4.1. Characteristicsofthepopulationstudied

Thepopulationofthisstudyconsistedin149patients(85men, meanage3512yearsand64women,meanage4310years), withameanBodyMassIndex(BMI)at25.75.7kg/m².Halfthemen andalmostathirdofthewomenweresmokers,halfthemenanda quarterofthewomenreportedalcoholconsumption,two-thirdofthe patientsweretakinganalgesicsorpsychotropicdrugs,athirdofthe menandhalfthewomenwereinvolved inasportactivity.Inall,

120 patients (80%) were working (as employees or independent workers), including 77.5% on sick leave with a mean sick leave durationatthetimeoftheevaluationof387332days(medianat 300days).Mostofthepopulationwasemployees(80%)(Table3)with aloweducationalattainment(34%withoutanydiplomaormiddle schooldiploma(Brevetdescolle`ges),44%hadanoccupationalhigh school diploma CAP/BEP, and 22% had a high school diploma (Baccalaureate)orhigher.Themostrepresentedsocialandoccupa- tional categories were: blue-collar workers (50%) and employees (33%),followedbywhite-collarworkers(12%),managersorhighlevel intellectual workers (3%)and farm workers(2%). Main sectorsof activitywerenon-retailtertiary(31%),industry(23%),retailtertiary (18%),construction work(15%)andagriculture(13%).The median lengthofservicewas6years(Range:1to33years).Accordingtothe Table1

ThresholdsforposturalandjointconstraintsandforMHL.

Ability SUMER2003study MSDthresholds Extrapolatedvalues DOLstandards

hpw % hpd % % %

Sitting 50

Standing 20 50

Walking 20 50

Climbing 25 33

Stairclimbing 25 33

Stooping 25 66

Kneeling 25 66

Crouching 25 66

Crawling 25 66

Reachinghigh 2 25 66

Reachinglow 2 25 66

HandlingDH 20 50 2 25

HandlingNDH 20 50 2 25

FingeringDH 4 50

FingeringNDH 4 50

Ability(correctioncoefficient) Maximumacceptablevalue(kg) Conditionalmaximumvalue(kg)

Loweringoccasionally0.4) 6 10

Loweringfrequently(0.4) 6 10

Loweringconstantly(0.4) 6 10

Raisingoccasionally(0.4) 6 10

Raisingfrequently(0.4) 6 10

Raisingconstantly(0.4) 6 10

Holdingoccasionally(1) 15 25

Holdingfrequently(1) 15 25

Holdingconstantly(1) 15 25

Carryingoccasionally(0.6) 9 15

Carryingfrequently(0.6) 9 15

Carryingconstantly(0.6) 9 15

MHL:manualhandlingofloads;kg:kilograms;MSD:musculoskeletaldisorders;DOL:U.S.DepartmentofLabor;hpw:hoursperweek;%:percentageonthebasisofaneight- hourworkday;hpd:hoursperday;DH:dominanthand;NDH:non-dominanthand.

Table2

Mainpathologyfortheindicationoftheevaluationandvalidityscores.

Disease n % Validityscore(/5)

(meanstandarddeviation)

Musculoskeletaldisorders(MSD)ofupperlimb 49 33.8 3.40.9

Rotatorcuffpathology 21 14.5 3.40.9

Entrapmentsyndromes(carpaltunnelsyndrome,ulnartunnelsyndrome,thoracicoutletsyndrome) 13 9.0 3.51.0

MSDwithoutprecisionormultipledisordersofupperlimb 11 7.6 3.50.8

Othertendonpathologies(medialepicondylitis,lateralepicondylitis) 4 2.8 3.00.8

Spinalpathology 19 13.1 4.20.5

Otherdiseases 77 53.1 3.90.7

Acquiredbraindamage(stroke,traumaticbraininjury,multiplesclerosis,tumors,abscess) 22 15.2 4.00.5

Trauma/multipletrauma 22 15.2 4.00.7

Peripheralneurologicalinjury(polyradiculoneuritis,Guillain-Barresyndrome) 12 8.3 3.71.0

Rheumatologyandsystemicdisease 10 6.9 3.90.6

Congenitalbraindamage(cerebralpalsy,geneticdisease,dyspraxia) 3 2.1 3.71.5

Spinalcordinjury(paraplegia,quadriplegia) 3 2.1 4.00.0

Other(Amputation,burnvictim,cardiology) 5 3.4 4.00.7

Total 145 100.0 3.80.8

Oswestryscore, 41% of patients hada minimal disability, 41% a moderatedisability,18%asevereorextremelyseveredisabilityand 80%reported‘‘notfeelingabletowork’’.

Among the 86 patients questioned on the workstation’s organizational demands (unemployed persons and apprentices excluded), most had an open-ended contract/official contract, wereworkingfulltime,duringthedaytime,andreportedhavinga lowautonomy(lowdecisionabilityand/orlowpossibilityofself- management)withveryfewopportunitiesforcareerdevelopment (Table4).

4.2. Functionalcapacityevaluation(FCE)andworkplacedemands (WPD)

Regarding WPDs, occasional MHL, abilities ‘‘reaching high’’,

‘‘reaching low’’,‘‘handlingwith thedominanthand’’, ‘‘handling with the non-dominant hand’’ and ‘‘stooping’’ were the most represented and the onesmost often exceedingthe maximum acceptablevalues(Fig.4).Themeantotalarduousnessindexfor thejobwas61.515.8/100.

ConfrontingtheresultsoftheFCsandWPDsunderlinedahigher rateofpresumptionofmismatchfortheabilities‘‘reachinghigh’’

(34%),‘‘reachinglow’’(64%),‘‘handlingwiththe dominanthand’’

(47%), ‘‘handlingwith the non-dominant hand’’ (34%) and MHL (aboutathird).Conversely,theability‘‘stooping’’whichfrequently went above the maximum acceptable values only led to a presumptionofmismatchin18%ofthecases.Forthesubpopulation ofpatients referredfor MSDofthe upper limb,themismatches concerned mostly the following abilities: ‘‘reaching high’’ and

‘‘reachinglow’’(47%and71%respectively)(Table5).

For stay-at-work, half the recommendations related to the resultsoftheevaluationwereinfavorofvalidatingthestay-at- workwithorwithoutjobaccommodations,onequarterledtoa definitelyunfitnessand 9%toa temporary unfitness.Aspartof careerchange,twothirdoftherecommendationswerelimitedto evaluating theresidual abilities and didnot proposea specific orientation,leavingthistasktotherecipientsoftheevaluationand physicianswhoprescribedtheevaluation.

4.3. Dataassociationandcorrelationanalyses

A linear association washighlighted between the Oswestry scoreand ‘‘not feelingabletowork’’ (P<0.0001).Thus, 59% of patientswithminimaldisabilitydidnot‘‘feelabletowork’’vs.96%

ofpatientswithaseveretoextremelyseveredisability.Theglobal FCEperformanceindexwasstatisticallydifferentaccordingtothe notionof‘‘feelingabletowork’’.Patientswho reported‘‘feeling abletowork’’hadameanscoreof42vs.64forpatientswho reported ‘‘not feeling able to work’’ (P=0.042). No significant associationwasreportedbetweenhavinganupperlimbimpairment oritslateralityandbeingonsickleaveorwiththeOswestryscore.

Eventhoughtheglobalperformanceindexwasnotassociatedwith beingonsickleave(93patients),WPDrelativeFCs‘‘handlingwiththe dominanthand’’wereassociatedwithbeingonsickleave(89%vs.

Table3

TypeofErgo-Kitassessmentaccordingtothesocialandoccupationalstatusandits indication.

TypeofEKassessment WPD+FCE FCEonly

n % n %

Socialandoccupationalstatus

Employee(n=116) 82 70.7 34 29.3

Unemployedperson(n=16) 4 25.0 12 75.0

Apprentice(n=11) 2 18.2 9 81.8

Self-employedperson(n=4) 4 100.0 0 0.0

Disability(n=2) 0 0.0 2 100.0

Indication

Stay-at-work,RTW^*(n=94) 84 89.4 10 10.6

Vocationalguidance,careerchange(n=36) 3 8.3 33 91.7 Occupationalrehabilitation(n=12) 3 25.0 9 75.0

Otherreason(n=2) 0 0.0 2 100.0

Withoutreason(n=5) 2 40.0 3 60.0

EK:Ergo-Kit;WPD:workplacedemands;FCE:functionalcapacityevaluation;RTW:

returntowork.

Table4

Workstation’sorganizationaldemands.

n %

Typeofcontract

Open-endedcontract/official 69 84.1

Fixed-termcontract 7 8.6

Interim 4 4.9

Employeeofprivateemployer 1 1.2

Other 1 1.2

Workschedule

Full-time 69 84.1

Part-time 13 15.9

Workrate

Daywork 40 48.2

Two-shiftsystem 18 21.7

Three-shiftsystem 7 8.4

Nightwork 3 3.6

Other 15 18.1

Autonomyatwork

Low 49 59.0

Medium 20 24.1

High 14 16.9

Opportunitiesforcareerdevelopment

Verylow 40 46.5

Low 13 15.1

Medium 21 24.4

High 5 5.8

Veryhigh 2 2.2

Table5

PresumptionsofmismatchbetweenWPDsandFCs.

FCE–WPD Totalsample

(n=84)

MSDsample (n=38)

n % n %

Loweringoccasionally 27 32.1 10 26.3

Loweringfrequently 29 34.5 15 39.5

Loweringconstantly 17 20.2 7 18.4

Raisingoccasionally 29 34.5 16 42.1

Raisingfrequently 25 29.8 12 31.6

Raisingconstantly 13 15.5 7 18.4

Holdingoccasionally 26 31.0 13 34.2

Holdingfrequently 31 36.9 16 42.1

Holdingconstantly 18 21.4 8 21.1

Carryingoccasionally 21 25.0 6 15.8

Carryingfrequently 6 7.1 3 7.9

Carryingconstantly 3 3.6 1 2.6

Sitting 5 6.0 0 0.0

Standing 5 6.0 3 7.9

Walking 6 7.2 1 2.6

Climbing 13 15.7 4 10.5

Stairclimbing 3 3.6 0 0.0

Stooping 15 18.1 7 18.4

Kneeling 2 2.4 0 0.0

Crouching 5 6.0 1 2.6

Crawling 1 1.2 1 2.6

Reachinghigh 28 33.7 18 47.4

Reachinglow 53 63.9 27 71.1

HandlingDH 39 47.0 18 47.4

HandlingNDH 28 33.7 11 28.9

FingeringDH 6 7.2 3 7.9

FingeringNDH 6 7.2 2 5.3

WPDs:workplacedemands;FCs:functionalcapacities;FCE:functionalcapacity evaluation; n:number; %: percentageof mismatches; MSD: musculoskeletal disorders;DH:dominanthand;NDH:non-dominanthand.

191%;P=0.006).WhentheserelativeFCswerelow,patientstended to be onsick leave. Furthermore, there were moderateto strong correlationsbetweenrelativeFCsandthedurationofsickleavefor the abilities ‘‘holding constantly’’ (

r

= 0.753) and ‘‘stooping’’

(

r

= 0.386).ThelowertheserelativeFCs,thelongertheduration ofthesickleaveswas(Table6).Finally,lowtomoderatecorrelations werealsohighlighted betweentheOswestryscoreandtheglobal performanceindex (

r

=0.239)aswellasformost abilitiestested duringtheFCE(22outof27).Thestrongercorrelationcoefficients were observed for ‘‘lowering occasionally’’ (

r

= 0.412), ‘‘sitting’’

(

r

= 0.553), ‘‘standing’’ (

r

= 0.578) and ‘‘handling with the dominanthand’’(

r

= 0.403)(Table6).Lowtomoderatecorrelations were underlined between the arduousness of the job and the Oswestryscore(

r

=0.402)aswellasbetweenthearduousnessindex andtheglobalperformanceindex(

r

=0.305).Patientsreporting‘‘not feelingabletowork’’hadahigherarduousnessindex(64.614.8vs.

48.413.5;P <0.001).Furthermore,there werelowcorrelations betweentheWPDsandarduousnessindexfortheabilities‘‘lowering frequently’’ (

r

=0.301) and very low correlations for ‘‘raising

frequently’’ (

r

=0.214), ‘‘stooping’’ (

r

=0.254) and ‘‘crouching’’

(

r

=0.232). Conversely,thearduousness scoredecreasedwiththe ability‘‘sitting’’(

r

= 0.254)(Table6).Nosignificantassociationwas evidencedbetweenthearduousnessindexandbeingonsickleave.

Howeverthemeandurationofsickleavesincreasedalongthesame pathasthearduousnessindex(

r

=0.265).

5. Discussion

MHL and in particular the less frequent ones (<32/day, generally corresponding to the heaviest tasks), postures with armsaway fromthebody,and repetitive motionsoftheupper limbswereamongthemostfrequentWPDs,theonesgoingabove exposure thresholdvaluesand triggeringmostpresumptions of mismatchbetweentheFCsofapersonandtheWPDsinourstudy.

The‘‘stooping’’ posture,even thoughquitefrequent and,inour study,frequentlyabovesetthresholdvalues[17–19],ledtoless presumptionsofmismatch.Thesesituationshadalowtomoderate correlationwithindicatorsofsickleaveandarduousness.Thework Fig.4.Distributionofthephysicalworkplacedemands.^*DH:dominant-hand;NDH:non-dominanthand.

arduousnessindexwascorrelatedtotheOswestryscoreaswellas theglobalFCEperformanceindex.Patientsreporting‘‘notfeeling abletowork’’hadahigherarduousnessindexandthelongerthe durationofthesickleave,thehigherthearduousnessindexwas.

Toourknowledge,thestudyofthe‘‘WPDrelativefunctional capacities’’ has never previously been evaluated. Most studies conductedonFCEswereconductedinpopulationsofpatientswith MSD,whichisnotthecaseofourstudywerenoselectionwasdone according to the pathology. The mean BMI of the studied population (25.75.7kg/m²) showeda tendencyto being over- weightwhich could have an impact inseveral situations andon occupationalmotionsandthusonFCEresults,yetthisimpactwasnot evaluatedinourstudy.Theredoesnotseemtobeanyselectionbias relatedtothepatients’recruitment,noranyinterpretationbiasfor FCEresultsthanksto thestrictfollow-upoftheEK methodology.

Therecouldneverthelessexistamemorybias(orrecallbias:apatient probably remembers more past exposures related to his or her pathology) of occupational exposures that might influence WPD results.TherecouldalsobeaninterpretationbiasfortheWPDsdueto thefactthatdatacollectionrelatedtothejobareonlybasedonan interviewbetweenthepatientandtheoccupationaltherapistand doesnotincludeotheractorssuchastheOPoranergonomistviaan objectiveobservationoftheworkstation.WPDsreportedbypatients havealowvaliditywhenpatientsareaskedtoquantifytheduration orfrequencyofexposure[24].ThisiswhytheassessmentofWPDs andarduousnessindexbytheoccupationaltherapistbasedontasks andactionsdescribedsubjectivelybythepatientallowsaquantifi- cation closer to the real job, but requires for the occupational therapisttohaveagoodrepresentationofallthedifferenttypesof jobs.Ourstudyisbasedonunivariateanalysesnotallowingtobring ananswerontheindependentnatureofthehighlightedrelationships.

Thecorrelationcoefficientsinourstudyarecomparabletothoseof similarstudies[10,11]inspiteofsmallersamples.MostFCEmethods, includingtheEK,arebasedonabatteryoftestsreferringtothelistof

requirementsfromtheDictionaryofOccupationalTitles(DOT)[16]

listingWPDsandphysicalcapacitiesthataworkermusthaveinorder tomeettheseWPDs.ThevalidityandreliabilityoftheDOTarenot scientificallyvalidated[25]andinmostcasesDOTstandardsarewell above the threshold values commonly set, which limits their relevancefortheOP’spractice.

Even though initially used as part of PM&R, the EK brings relevant information for occupational healthcare professionals, especiallyforMHL.Thus,MHLtestsoftheEKhaveasatisfactory reliability (reproducibility)[6,7] and these tests have a low to moderate predictive value on the work disability risk and sustainableRTW[26,27].However,theEKevaluatestheFCsofa person,butonlypartiallyevaluateshisorherworkparticipation anddoesnotassesstheotherdimensionsofaperson’sfunctioning atwork,mainlyworkperformance[9,28].TheEKiscloseronthe onehandtojob-specificFCEssinceit allowstheanalysisofthe organizationalcontextand avery precisedescription ofthejob tasks.However,itdoesnotpermittosimulateworktasksandin thissenseisclosertogeneralFCEsbyitsstandardizedapproach and its quantitative evaluation strategy [29]. The EK is at the borderofthesetwoapproaches.Themostqualitativeapproaches offeredbyWCEsinaworkenvironmentareprobablymorelikelyto graspallaspectsofaperson’sfunctioningatwork,whichisquite complex,multidimensionalandevolvinginnature[9,30].Further- more,theEKcanhelpwiththenotionsofmismatchbetweenWPDs andFCs,whichisquitedifferentfromthenotionofmedicalfitness fordutyusedbytheOP.

OurresultssuggestthattheOswestryscorecouldbea good generalindicatorofFCEresultsanditsuseintheworkplacecould be useful for a quick evaluation of the worker’s capacities.

However,thismethodremainslimited,mainlyduetotheimpact of a person’s subjectivity and the fact that this score is only validatedin chroniclow backpain.Thepotentialinfluenceofa person’s subjectivity on the EK results suggests that before Table6

Spearmanrankcorrelationcoefficients.

Ability WPDrelativefunctional

capacityanddurationofsick leave

Oswestryscoreandfunctional capacityevaluation

Workarduousnessindexand workplacedemands

n r n r n r

Loweringoccasionally 50 0.313 136 0.412 82 0.061

Loweringfrequently 28 0.214 107 0.266 82 0.301

Loweringconstantly 12 0.204 107 0.219 82 0.14

Raisingoccasionally 41 0.0009 133 0.331 82 0.121

Raisingfrequently 22 0.021 102 0.153 82 0.214

Raisingconstantly 7 NC 102 0.068 82 0.025

Holdingoccasionally 47 0.109 141 0.32 82 0.08

Holdingfrequently 33 0.111 118 0.28 82 0.125

Holdingconstantly 10 0.753 118 0.222 82 0.036

Carryingoccasionally 39 0.104 141 0.32 82 0.039

Carryingfrequently 8 NC 118 0.291 82 0.105

Carryingconstantly 2 NC 118 0.222 82 0.009

Sitting 56 0.254 143 0.553 82 0.254

Standing 57 0.184 143 0.578 82 0.11

Walking 62 0.311 143 0.355 82 0.076

Climbing 30 0.183 143 0.126 82 0.02

Stairclimbing 44 0.06 143 0.146 82 0.172

Stooping 61 0.386 142 0.329 82 0.254

Kneeling 36 0.287 141 0.386 82 0.022

Crouching 46 0.078 142 0.272 82 0.232

Crawling 6 NC 143 0.223 82 0.035

Reachinghigh 62 0.238 142 0.306 82 0.067

Reachinglow 63 0.039 142 0.358 82 0.064

HandlingDH 63 0.122 143 0.403 82 0.026

HandlingNDH 63 0.074 142 0.229 82 0.038

FingeringDH 48 0.069 143 0.284 82 0.097

FingeringNDH 37 0.199 142 0.138 82 0.044

WPD:workplacedemands;n:numberofpeoplewithavailabledata;r:Spearman’srho;NC:notcalculated;DH:dominanthand;NDH:non-dominanthand.

interpretingtheresultsoneshouldverifytheir validityscore.A validityscorebelow4/5discardstheresultsand challengesthe initialindication(cognitivedisordersforexample).

Studieshaveshownthatthecorrelationbetweenself-percep- tion of disability (disability self-questionnaire, ‘‘feeling able to work’’) and performances to FCEs was low to moderate but significant;theability‘‘lowering’’wasmoderatelycorrelatedtothe disabilityscore;andthedisabilityscorewascorrelatedto‘‘feeling able towork’’, which is in accordance withour study’s results [10,11].Thesevariables reflectthemultifactordimension ofthe feelingsoftheworker-patienttowardstheperceivedarduousness ofthejob(postureconstraints,heavylifting,workorganization, support at work, etc.), the perceived health status, but also variablesrelatedtothemeaningofthejobperformed.Allthese elementsinfluenceandinteractwiththefeelingofbeingableto workand theRTWprocess. Thisis closer tothe‘‘self-efficacy’’

theorydevelopedbyateamfromQuebec[31].

6. Conclusion

FunctionalcapacityevaluationsaremostlyconductedinPM&R centersupontherequestofPM&Rphysicians.Theyarepartofthe patient’sglobalcaremanagement,infullpartnershipifnecessary, withtheOPinordertopromoteRTW.TheEKisanevaluationtool, itsresults canhelp guide thephysician’s decision and thought process,butitisnotatoolforanOPtodeterminetheworker’s medicalfitnessforduty.ThemainelementsprovidedbytheEK includeworkconditionsand their potentialmismatchwiththe patient’sFCsaswellasacertainnumberofelementsrelatedtothe worker’s self-perception of functional disability and ability to returntowork.

Disclosureofinterest

The authors declare that they have no conflicts of interest concerningthisarticle.

Acknowledgements

TheauthorswouldliketothankA.Molleand A.Bouchezfor theirhelpandavailability.

Appendices1&2. Supplementarydata

Supplementarydataassociatedwiththisarticlecanbefound,in the online version, at http://dx.doi.org/10.1016/j.rehab.2015.08.

002.

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