Evidence Based Orthopaedic Surgery
Dr Paul Della Torre
Orthopaedic Registrar
Concord/Canterbury Hospitals
History of EBM
• 1747 James Lind
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Ships Surgeon, British Navy
First ever systematic clinical trial, basic principles
6 interventions for scurvy prevention
Citrus of proven benefit
Implemented in voyages of James Cook, and British
Navy 1795.
• Questions established systems
• Locate, evaluate, incorporate best
available research into clinical practice
Evidence Based Medicine
• Defined as “…the conscientious, explicit,
and judicious use of current best evidence
in making decisions about the care of
individual patients.” Sackett et al, BMJ
1996.
• Evidence based practice involves
integrating clinical expertise with:
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Best available evidence
Patient factors/preferences
Priorities
Resources etc.
Process of EBM
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Formulate clinical question
Locate evidence
Critical appraisal
Incorporate into clinical practice
Evaluate effect of change on performance
Review practice, modify as required
Levels of Evidence
• Oxford Centre for Evidence Based
Medicine (CEBM)
 www.cebm.net
• Study question types:
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I
Therapy / Prevention, Aetiology / Harm
Prognosis
Diagnosis
Differential diagnosis / symptom prevalence study
Economic and decision analyses
II
Quality
III
IV
Bias
V
Study Type
• Therapy
 RCT > Cohort > Case control > Case series
• Diagnosis
 Cross-sectional analytic study
• Aetiology/Harm
 Cohort > Case control > Case series
• Prognosis
 Cohort study > Case control > Case series
• Prevention
 RCT > Cohort > Case control > Case series
• NB: SYSTEMATIC REVIEWS (including Meta
Analysis) – Highest level evidence for each
study type/
Definitions
• Systematic Review
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Overview of scientific literature on a specific problem
Thorough, defined literature search
Appraisal of individual studies identified
Summary of studies
• Meta Analysis
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Statistical technique
Combination of data from similar studies
Quantitative summary
Weighted average of individual study effects.
Where to look?
• Cochrane Collaboration
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Founded 1993, named after Archie Cochrane
Not for profit
Independent
Updated
• Produce:
 Cochrane Database of Systematic Reviews
(Quarterly)
 Cochrane Library
• www.cochrane.org
How to Find…
• www.ciap.health.nsw.gov.au
 Librarian
 IT Support
 CIAP Representative
Cochrane Library
Cochrane Systematic Reviews
• Abstract
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Background
Search strategy
Selection criteria
Data collection, analysis
Main results
Authors' conclusions
• Plain language summary
• PDF download
 Summary
 Main review
Level 1 Evidence
Recommendations
A balanced approach
• Exercise for improving balance in older
people
 34 studies, 2883 participants
 Interventions involving gait; balance; co-ordination
and functional exercises; muscle strengthening; and
multiple exercise types have greatest impact on
balance.
 Limited evidence that effects were long-lasting.
 Overall, a lack of standardised outcome measures
limiting conclusions re. efficacy.
Defy gravity?
• Interventions for preventing falls in older
people living in the community
 ~30% of people over 65 years of age living in the
community fall each year
 111 trials, 55,303 participants
 Reduced rate of falls and risk of falling:
o Multiple-component group exercise
o Individually prescribed multiple-component home-based exercise
o Tai Chi
 Reduced rate of falls:
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Assessment and multifactorial intervention
Gradual withdrawal of psychotropic medication
First eye cataract surgery
Pacemakers in carotid sinus hypersensitivity
 Reduced risk of falls:
o Home safety interventions in patients with severe visual impairment
o Prescribing modification programme for primary care physicians
Does being hippy help?
• Hip protectors for preventing hip fractures
in older people
 15 studies, over 15,000 elderly rest or nursing home
residents or older adults living at home.
 No or marginal reduction in hip fracture, pelvic or
other fractures incidence
 No major adverse effects reported
 Compliance, particularly in the long term is poor due
to discomfort and practicality
To cement or not to cement…?
• Arthroplasties (with and without bone
cement) for proximal femoral fractures in
adults
 19 trials, 2115 patients
 No significant difference for unipolar vs bipolar
hemiarthroplasty.
 Tendancy for cemented hemiarthroplasty to reduce
postop pain and improved mobility at 1yr postop.
 No significant difference in surgical complications
between cemented and uncemented
 Significantly longer operative times, but better
functional outcome scores for THR.
To drain or not to drain…?
• Closed suction surgical wound drainage after
orthopaedic surgery
 36 studies, 5464 participants with 5697 surgical wounds
 Hip/knee replacement, shoulder surgery, hip fracture
surgery, spinal surgery, ACL reconstruction, open
meniscectomy and fracture fixation surgery
 No difference in wound infection, haematoma,
dehiscence or re-operation rate
 Blood transfusion required more frequently with drains
 Reinforcement of wound dressings and bruising more
common without drains
 Insufficient evidence from randomised trials to support
the routine use of closed suction drainage in
orthopaedic surgery.
To stop the clot
• Heparin, LMW heparin and physical
methods for preventing DVT and PE
following surgery for hip fractures
 31 trials, 2958 female and elderly patients
 Unfrac and LMW heparins protect against lower limb
DVT
 Foot and calf pumping devices appear to prevent
DVT, may protect against PE, and reduce mortality,
but compliance a problem
 Trial quality an issue
 Aspirin needs to be included
Running on bone
• Exercise for osteoarthritis of the knee
 32 studies, 3616 participants
 Outcome of improved physical function
 Dependant on provision of a supervised exercise
program
 Land-based therapeutic exercise has short term
benefit in reduction of knee pain and improved
physical function in knee OA
 Magnitude of the treatment effect comparable to
estimates reported for NSAID drugs
The ankle dilemma
• Immobilisation and functional treatment for
acute lateral ankle ligament injuries in
adults
 21 trials, 2184 participants
 Functional treatments compared with immobilisation
 No differences between varying types of
immobilisation, immobilisation and physiotherapy or
no treatment
 Functional treatment was found to improve:
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Number returning to sport in the long term
Time taken to return to sport
Return to work at short term follow-up
Time taken to return to work was shorter
Likelyhood of persistent swelling at short term follow-up
Numbers suffering from objective instability as tested by stress X-ray
Patient satisfaction
 Many low quality trials, most of differences not
significant when excluded
What to pop…
• Paracetamol for osteoarthritis
 15 studies, 5986 participants
 Compare efficacy and safety of paracetamol versus
placebo versus NSAIDs for treating OA
 NSAIDs are superior to paracetamol for improving
knee and hip pain due to OA.
 In OA with moderate-to-severe levels of pain,
NSAIDs are more effective than paracetamol.
Questions?