Gareth Jones (Nyborg, May 2008).ppt [Kompatibilitetstilstand]Dr Gareth Jones Senior Lecturer in Epidemiology One-Month Prevalence Shoulder: 24% Low back: 28% Headache: 15% Abdomen:

1

Occupational exposures and rotator cuff disease / biceps tendinitis

Aberdeen Pain Research CollaborationEpidemiology Group, Department of Public Health

Dr Gareth JonesSenior Lecturer in Epidemiology

One-Month Prevalence

Shoulder: 24%

Low back: 28%

Headache: 15%

Abdomen: 8%

Foot: 13%

Low back: 28%

Thigh / Hip: 28%

Hand: 15%

Knee: 21%

Abdomen: 8%

Shoulder Pain Aetiological Studies

• Miranda et al 2001– Physical strenuousness – Working with flexed trunk– Working in twisted posture – Working with rotated neck – Working with elevated arms

• Palmer et al 2001a– Keyboard use

• Bergenudd et al 1988– Workplace dissatisfaction

• Palmer et al 2001b– Use of vibrating tools

2

Limitations of Aetiological Studies

• Cross-sectional / Case-control studies– Onset of shoulder pain– Temporal course of events

• Studies limited to one workforce– External validity – Particular combinations of exposures

• Healthy worker effect– Solution: Longitudinal studies– Limitation: Very resource intensive

Harkness et al 2003

• Prospective cohort

• 12 occupational groups

• 803 subjects free of shoulder pain

• Follow-up– 12 months – 24 months – New prevalence: 15% – New prevalence: 15%

Harkness et al 2003

10.0

Pai

n O

nset

10.0

Pai

n O

nset

0.1

1.0

OR

(95%

CI)

of S

houl

der P

YesNo

Lift heavyweights

0.1

1.0

OR

(95%

CI)

of S

houl

der P

Push / pullweights

Lift aboveshoulder

Work withelevated arms

Carry weighton shoulder

YesNo

Lift heavyweights

Fredriksson et al 1999

• Prospective study

• Range of occupations

• 485 subjects

• Predictors of shoulder pain onset– High mental load at work– Monotonous work– Low social support

3

Prognosis of Shoulder Pain

• Few studies in general population

• Patients in primary care– More severe symptoms than general populationy p g p p– Croft et al 1996

• 49% reported a complete recovery at 18 months

– van der Windt et al 1996• 59% fully recovered at 12 months

Rotator Cuff / Biceps Tendon

Shoulder Pain

• Pain can originate from many sites– Tendinitis– Bursitis– Referred painp

• Cervical or thoracic spine• Internal organs

• Lack of evidence as to what clinical conditions (with pain as a symptom) have distinct aetiological aspects

Rotator Cuff / Biceps Tendon

• Four muscles and their tendons– Subscapularis– Supraspinatus– Infraspinatusp– Teres minor

• Tendons form continuous cuff around humeral head

• Pathology– Inflammation– Damage (tear)

4

Case Ascertainment

• Presenting symptoms– Pain (antero-laterally)– Inhibition of movement

• Gold standard– Imaging

• Physical findings– Tenderness on palpation– Clinical examination

• Jobe• Gerber• Neer• Hawkins

• Clinical practice– Patient history– Clinical examination

Descriptive Epidemiology

• General population– Seldom recorded– Estimates

• ~10% of cases of persistent shoulder pain• ~85% of patients presenting to primary care with shoulder pain have a85% of patients presenting to primary care with shoulder pain have a

rotator cuff tear

• Working population– Rotator cuff syndrome: 6.8% (men) and 9.0% (women)– Rotator cuff tendinitis: 2.0%– Rotator cuff tendinitis: 3.8%– Biceps tendinitis: 0.5%

Descriptive Epidemiology

• Inconsistent evidence of gender differences

• Clear increase in prevalence with age– Longer cumulative exposure to risk factorsg p– Age-related degenerative changes in rotator cuff tendons– Disease of long duration

Occupation

• Supraspinatus tendinitis– House painters 4.4%– Fish processing workers 5.0%– Slaughterhouse workers 6.9%

W ld 27%– Welders 27%

• Infraspinatus tendinitis– Fish processing workers 12%

• Supraspinatus tendon pathology (MRI)– Machinists / Mechanics / Painters 38%

Occupationalaetiology?

5

Occupation

• Only a marker for aetiological factor

• Provides no task-specific information

• Need to study specific work exposures

Aims and Objectives

Aims and Objectives

• To summarise the existing epidemiological evidence with respect to the associations between occupational-related exposures and rotator cuff disease and / or biceps tendinitis

• Specific objectives– To present exposure-response patterns, where present– To assess any impact of gender– To evaluate the evidence with respect to prognosis

Outcome Definition

• Rotator cuff disease and / or biceps tendinitis

• Standard definitions– No diagnostic guidelines for physical diseases in ICD-10g g p y– No consensus reached re: diagnostic criteria for shoulder

disorders

• Outcome:– Exception:

Pain plus objective physical findingsShoulder pain plus tenderness on palpation alone

6

Methods

Methods: Literature Search

• Electronic bibliographic databases– Medine (from 1966)– Embase (from 1980)

• Search date– February 7th, 2007

• Three searches– Outcomes of interest– Epidemiological search terms– Exposures of interest


‘Shoulder’search

shoulderrotator cuff

i t

‘Epidemiology’search

epidemiolo$aetiolo$

ti l $

‘Occupational’search

occupation$employment$j b$ “OR”supraspinatus

infraspinatusteres minorsubscapularisbiceps tend$glenohumeralimpingement

“OR”

etiolo$risk factor$predictive factor$risk marker$odds ratio$hazard ratio$risk ratio$rate ratio$prevalence ratio$relative risk$

“OR”

job$work$task

“OR”


‘Shoulder’search

‘Epidemiology’search

‘Occupational’search

Combination(‘AND’)

Titlesfor review

Removeduplicates

Limit to EnglishLimit to Human

7

Methods: Review Strategy

Reviewer 2Reviewer 1

Titlesfor review

Reviewer 3

ReviewabstractsDiscard

Agree to reject Agree to acceptDisagree

Methods: Assessing Study Quality

• Combination– Objective characteristics– Subjective assessment

T i• Two reviewers

• Ten areas of methodology– Study design – Confounding– Sample size – Blinding– Sampling method – Objective exposure– Participation / follow-up – Exposure-response data– Bias – Outcome measurement

Methods: Contributory Evidence

• Very stringent outcome criteria– Anticipated few studies

• Many studies with self-reported shoulder painy p p

• Contributory evidence– Studies identified from literature search– Subjectively measured outcome– High quality prospective cohort studies

Methods: Grading of Evidence

Evidence of causal relationshipGrade

Strong evidence (causal relationship is very likely)+++

Moderate evidence (causal relationship is likely)++

Weak evidence (causal relationship is possible)+

Insufficient evidence of a causal association0

Evidence suggesting lack of causal association–

8

Main Findings

Results: Literature Search

‘Outcome’n = 56,174

‘Epidemiology’n = 1,456,900

‘Occupational’n = 1,305,486

Boolean ‘AND’n = 1062

Titles for reviewn = 651

Duplicatesn = 301

English / Humann = 110

Inclusion / Exclusion Criteria

• Review of titles– Suggestion that outcome included pain / disability in the

shoulder / neck / upper limb

• Review of abstracts– Explicit mention that outcome was assessed by self-report– Explicit mention that only non-occupational exposures were

assessed

Inclusion / Exclusion Criteria

• Review of full papers – Outcome– Study used solely a self-reported outcome– Outcome was pain plus tenderness alone

• Review of full papers – Exposure– Study examined only non-occupational exposures

• Review of full papers – Risk Effects– No data on the magnitude of any risk effects– No data from which risk effects were calculable

9

ABSTRACTS

Discardn = 324

Results: Literature Review

TITLESn = 651

Includen = 13

Discardn = 99

FULL PAPERSn = 112

Discardn = 215

n = 327

Included Studies: Overview

• 13 original articles – Andersen & Gaardboe 1993 – Svendsen et al 2004a– Chiang et al 1993 – Svendsen et al 2004b– Stenlund et al 1993 – Miranda et al 2005

F t & A d 1999 W t l 2005– Frost & Andersen 1999 – Werner et al 2005– Kaergaard & Andersen 2000 – Melchior et al 2006– Punnett et al 2000 – Walker-Bone et al 2006– Frost et al 2002

• 12 studies– Kaergaard & Andersen 2000 – Frost et al 2002


• Different study designs– Cross-sectional n = 10– Case-control n = 1– Cohort n = 2

• Location– Northern Europe n = 8– Europe other n = 2– USA n = 2– Elsewhere n = 1


• Different populations– Sewing machine operators – Automobile industry– Fish processing – Machinists– Construction – House painters

Sl ht h Offi k– Slaughterhouse – Office workers– Chemical factory – General population

10

Included Studies: Outcomes

• Shoulder pain with physical findings

• Rotator cuff syndrome / Rotator cuff disorder

• Shoulder tendinitis / Chronic rotator cuff tendinitis• Shoulder tendinitis / Chronic rotator cuff tendinitis

• Shoulder impingement syndrome

• Rotator cuff tendinitis and / or myofascial pain syndrome

• Supraspinatus tendinitis

Included Studies: Exposures

• Exposures– Binary– Cumulative exposure

• Months / Years

Proportion– Proportion• Job cycle• Maximum voluntary contraction

• Exposure measurement– Questionnaire / Interview– Sub-group measurement– Sub-group observation / video

Contributory Evidence

• High quality cohort studies, self-report outcome

• Papers: n = 7

• Reported outcomes– Shoulder pain alone– Shoulder pain with or without neck / upper limb pain

Occupational Exposures

• Physical exposures– Position of upper limb– Manual handling / force– Repetitive tasks

Oth h i l– Other physical exposures

• Psychosocial exposures

11

Position of Upper Limb

• Papers: n = 6

• Conclusion– Moderate [++] to Strong [+++] evidence to suggest a causal [ ] g [ ] gg

relationship between working with arms in an elevated position and rotator cuff disease / biceps tendinitis


10.0

r Dis

orde

r

Walker-Boneet al 2006

10.0

r Dis

orde

r


Svendsen et al 2004b10.0

r Dis

orde

r

Svendsen et al 2004b Miranda et al 2005Walker-Boneet al 2006

0.1

1.0

OR

(95%

CI)

of S

houl

der

1hr

Work with handsabove shoulders

0.1

1.0

OR

(95%

CI)

of S

houl

der

1hr


90o (months)

>24

0.1

1.0

OR

(95%

CI)

of S

houl

der

90o (months)

>24 None 1-3 4-13 14-23 >23

Duration (yrs) working with handabove shoulder >1hr per day

1hr



• Provides evidence to support association

• Miranda et al 2001– Working with arms above shoulderg

• Harkness et al 2003– Working with hands above shoulder level– Lifting heavy weights above shoulder level


• Evidence to suggest a causal relationship– Moderate [++] to Strong [+++]– Consistent evidence across a number of studies in a number

of different occupational environmentsSupported by high quality cohorts with subjective outcomes– Supported by high quality cohorts with subjective outcomes

• Insufficient studies presenting robust exposure-response data– Not possible to inform exposure standards

• Degrees of elevation• Time with arms elevated

– Not possible to identify ‘safe’ limits of exposure

12





Manual Handling / Force

• Papers: n = 8

• Conclusion– Moderate evidence [++] to suggest a causal relationship [ ] gg p

between manual handling / occupational force requirements and rotator cuff disease / biceps tendinitis


10.0

r Dis

orde

r

Chiang et al 199310.0

r Dis

orde

r

Miranda et al 2005Chiang et al 199310.0

r Dis

orde

r

Miranda et al 2005Chiang et al 1993 Frost et al 2002

0.1

1.0

OR

(95%

CI)

of S

houl

der

No Yes

Upper limb force-ful movements

0.1

1.0

OR

(95%

CI)

of S

houl

der

None 1-3 4-13 14-23 >23

Duration (yrs) of frequent lifting:>5kg, >2 time / min, >2hrs / day

No Yes


0.1

1.0

OR

(95%

CI)

of S

houl

der

None 1-3 4-13 14-23 >23

Duration (yrs) of frequent lifting:>5kg, >2 times / min, >2hrs / day

No Yes


Ref 10%


• Evidence not consistent

• Werner et al 2005– No difference in peak force requirement between cases

(persons with incident shoulder tendinitis) and controls

• Svendsen et al 2004a– Supraspinatus tendinopathy– Lifetime shoulder force requirements

• Low OR: 1.0• Medium 1.2 (0.5-3.2)• High 0.7 (0.3-1.7)

13


• Provides evidence to support association

• Harkness et al 2003– Lifting weightsg g– Carrying weights on one shoulder

• Andersen et al 2003– Force requirements


• Evidence to suggest a causal relationship– Moderate [++]– A number of studies have observed a positive relationship

between this exposure and outcomeSupportive contributory evidence– Supportive contributory evidence

• Not all studies have provided consistent evidence





Repetitive Tasks

• Papers: n = 5

• Conclusion– Weak evidence [+] to suggest a causal relationship between [ ] gg p

repetitive tasks and rotator cuff disease / biceps tendinitis

14

Repetitive Tasks

10.0

r Dis

orde

r


r Dis

orde

r

Chiang et al 1993 Frost et al 200210.0

r Dis

orde

r

Frost et al 2002 Frost et al 2002Chiang et al 1993

0.1

1.0

OR

(95%

CI)

of S

houl

der

No Yes

Repetitive movements of arm

0.1

1.0

OR

(95%

CI)

of S

houl

der

No Yes


No Yes

Repetitive manualhandling

0.1

1.0

OR

(95%

CI)

of S

houl

der

No Yes

Repetitive manualhandling

None 15No Yes



• Inconsistent

• Andersen et al 2003– Shoulder movements (per minute)(p )– Increase in likelihood of shoulder pain

• Harkness et al 2003– Repetitive arm / wrist movements– No increase in likelihood of shoulder pain

Repetitive Tasks

• Evidence to suggest a causal relationship– Weak [+]– Evidence across a number of studies suggesting a positive

relationshipInconsistent supporting evidence using subjective outcomes– Inconsistent supporting evidence using subjective outcomes

– Cannot rule out bias or confounding – particularly by manual handing / force requirements

• Insufficient studies examining repetition and force requirements independently

Combination: Force & Repetition

10.0

r Dis

orde

r

Frost et al 2002

0.1

1.0

OR

(95%

CI)

of S

houl

der

High freq,Low force

Low freq,High force

High freq,High force

Referencegroup

Low freq,Low force

15

Interaction: Force * Repetition

10.0

r Dis

orde

r


r Dis

orde

r


r Dis

orde

r


r Dis

orde

r

Chiang et al 1993

0.1

1.0

OR

(95%

CI)

of S

houl

der

Forceful movementsof upper arm

No Yes No Yes

Repetitive movementsof upper arm

0.1

1.0

OR

(95%

CI)

of S

houl

der


No Yes No Yes


Yes

Interaction offorce * repetition

0.1

1.0

OR

(95%

CI)

of S

houl

der


No Yes No Yes


Yes


Expected

0.1

1.0

OR

(95%

CI)

of S

houl

der


No Yes No Yes


Yes


Expected Actual

Interaction: Force * Repetition

• Evidence to suggest a causal relationship– Insufficient [0]– Data is sparse– No contributory evidence





Occupational Vibration

• Papers: n = 2

• Miranda et al 2005– Working with vibrating tool,

>2hrs /day

• Stenlund et al 1993– Per tertile increase in work-

life exposure

• Conclusion– Insufficient evidence [0] to suggest a causal relationship

between occupational vibration and rotator cuff disease / biceps tendinitis

• None OR: 1.0• 1-3yrs 0.6 (0.1-4.6)• 4-13yrs 2.5 (1.0-5.9)• 14-23yrs 3.5 (1.5-7.8)• >23yrs 1.4 (0.5-4.4)

• Right shoulder 1.9 (1.0-3.4)• Left shoulder 2.5 (1.1-5.9)

16

Occupational Driving

• Papers: n = 1

• Miranda et al 2005– Driving >4hrs / day, >3

months / year

• Conclusion– Insufficient evidence [0] to suggest a causal relationship

between occupational driving and rotator cuff disease / biceps tendinitis

• None OR: 1.0• 1-3yrs 2.6 (0.9-7.2)• 4-13yrs 1.4 (0.6-3.5)• 14-23yrs 2.7 (1.1-6.4)• >23yrs 1.1 (0.4-3.0)





Work Demands

10.0

r Dis

orde

r

Miranda et al 200510.0

r Dis

orde

r

Miranda et al 2005 Svendsen et al 2004b10.0

r Dis

orde

r

Miranda et al 2005 Svendsen et al 2004b Walker-Boneet al 2006

0.1

1.0

OR

(95%

CI)

of S

houl

der

Low High

0.1

1.0

OR

(95%

CI)

of S

houl

der

Low High Low High

0.1

1.0

OR

(95%

CI)

of S

houl

der

Low High Low High No Yes

Control over Work / Job Strain

10.0

r Dis

orde

r

Svendsen et al 2004b10.0

r Dis

orde

r

Svendsen et al 2004b Walker-Boneet al 2006

10.0

r Dis

orde

r

Kaergaard andAndersen 2000

Svendsen et al 2004b Walker-Boneet al 2006

0.1

1.0

OR

(95%

CI)

of S

houl

der

High Low

Control

0.1

1.0

OR

(95%

CI)

of S

houl

der

High Low

Control

Yes No

Control

0.1

1.0

OR

(95%

CI)

of S

houl

der

High Low

Strain

High Low

Control

Yes No

Control

17

Perceived Support

10.0

r Dis

orde

r


10.0

r Dis

orde

r



10.0

r Dis

orde

r



Svendsen et al 2004b

0.1

1.0

OR

(95%

CI)

of S

houl

der

High Low

0.1

1.0

OR

(95%

CI)

of S

houl

der

High Low Yes No

0.1

1.0

OR

(95%

CI)

of S

houl

der

High Low Yes No High Low


• Inconsistent findings– Work demands– Control over work

• Evidence

• Perceived (lack of) support– Work not entirely consistent– Overall suggestion of

positive association– Small effect• Evidence

– No effect– Effect of modest and

non-significant magnitude

• Conclusion– Insufficient [0] evidence to suggest a causal relationship between

most psychosocial exposures and rotator cuff disease / biceps tendinitis

– Perceived lack of support: weak evidence [+]

Other Issues

Other Issues

• Sensitivity analysis

• Gender

• Prognosis

18

Sensitivity Analysis

• Stringent outcome criteria

• Six of 13 studies may have included – Neck or upper arm pain onlypp p y– Pain on palpation alone– Myofascial pain syndrome– Adhesive capsulitis

• One study may have identified persons with pathology, but without pain

Query impacton findings ?


• Diagnostic inaccuracy – bias towards the null?

• Where an exposure is a risk factor for a disorder other than those of specific interestother than those of specific interest– Risk estimates may be augmented by the inclusion of

persons with competing diagnoses

• Exclusion of studies


++ / +++Upper arm elevation

Sensitivity analysis

Main findingsExposure

+ / 0Psychosocial factors

0Other physical / mechanical

+Repetitive tasks

++Manual handling / force

.

.

.

Other Issues


• Gender

• Prognosis

19

Gender Differences

Physical exposures

• Papers: n = 2

• Effect of similar magnitude in men and women– Working in a manual occupation– Working with hands above shoulder level– Working with hands away from body / behind trunk

Gender Differences

Psychosocial exposures

• Papers: n = 1

• Effect of similar magnitude in men and women– Work demands– Threat of being bullied or mentally abused

• Burnout– Men: Doubling in odds of symptoms (non-significant)– Women: Halving of odds of symptoms (non-significant)

Other Issues


• Gender

• Prognosis

Prognosis

• Parallel identification and review of literature– Bibliographic databases– Outcome and exposure information– Additional key-words

Prognosis / disability / recovery / sickness absence / consequences• Prognosis / disability / recovery / sickness absence / consequences

• Papers: n = 3

• Conclusion– Insufficient evidence [0] to suggest any causal relationships– Favourable outcome in large proportion of patients– Duration of treatment varies between individuals

20

Summary

Summary

EvidenceExposure

++ / +++Working with arms in an elevated position *

++Manual handling / occupational force requirement

+Repetitive tasks (independent of force)

0Other physical / mechanical exposures

* Robust to exclusion of studies with potential diagnostic inaccuracy

*

Summary

EvidenceExposure

+Perceived (lack of) support at work

0Perceived occupational demands

0Perceived (lack of) control at work

0Other psychosocial factors

0Factors relating to prognosis

Limitations of Current Research

• Paucity of high quality prospective cohort studies

• Few studies presenting robust exposure-response data– Not possible to inform exposure standards– Not possible to identify ‘safe’ limits of exposure

• Insufficient evidence to be able to distinguish– Exposures that lead to pathological changes– Exposures that aggravate symptoms that originate from pre-

existing shoulder pathology

21

Acknowledgements

• University of Aberdeen– Dr Nirupa Pallawatte– Dr Ashraf El-Metwally– Dr Finlay Dick– Professor Gary Macfarlane

• SC-DSOEM– Dr Susanne Svendsen– Dr Johan Andersen– Dr Sigurd Mikkelsen

y– Professor David Reid • External Review

– Dr Alex Burdoff– Mr Jens Ivar Brox


High ScoreLow ScoreRatingCriteria

Cohort study; long follow-up

Cross-sectional study

Range: 0 – 3 ObjectiveStudy design

>1000 participants85% participation

22


High ScoreLow ScoreRatingCriteria

Adjustment for 4+ key confounders

No adjustment for key confounders

Range: 0 – 3 ObjectiveConfounding

Blinding; robust methodsNo blinding

Range: 0 – 2 SubjectiveBlinding

Objective / 2+ observers / video

Subjective assessment

Range: 0 – 3 Subjective

Exposure measurement

Exposures on quantitative scale

Dichotomous exposures

Range: 0 – 3 Objective

Exposure-response data

Full clinical examPoor quality measurementRange: 0 – 3 Subjective

Outcome measurement


TITLESn = 651

Review of Titles

Reviewer 3(added n = 80)

Review abstractsn = 327

Discardn = 324

Agree to rejectn = 241

Agree to acceptn = 247

Disagreen = 163


ABSTRACTSn = 327

Review of Abstracts


Review full papersn = 112

Discardn = 215



Disagreen = 52


FULL PAPERSn = 112

Review of Full Papers


Includen = 13

Discardn = 99



Disagreen = 22

23

Results: Study Quality

• Maximum quality rating in all areas n = 0

• High quality n = 7– Maximum or maximum-1– At least five criteria

• Recent studies– Higher quality

Documents

Gareth Jones (Nyborg, May 2008).ppt [Kompatibilitetstilstand]Dr Gareth Jones Senior Lecturer in Epidemiology One-Month Prevalence Shoulder: 24% Low back: 28% Headache: 15% Abdomen: