Assessment of outcome after joint replacement Presentation 11 02 2015
1.
Measuring Outcome
after hip and knee
replacement
Mr Dipak Raj, FRCS
Consultant Orthopaedic Surgeon
Mr D Raj, Consultant Orthopaedic
Surgeon, Pilgrim Hospital, Boston
3. Ideal outcome tool
Validated
Reproducible
Comparable
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
4. Classification of outcome
measures
Subjective
Objective
Generic
Specific to
a joint
a disease
a specific patient group Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
5. Questionnaire based outcome
measures
Patient reported outcome measures (PROMs)
Objective
combined
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
6. Questionnaire based outcome
measures
Advantages
Self-administered
Simple
Cost effective
Reproducibility
Reliability
Internal consistency
Responsiveness to change
Terwee CB et al. J Clinical epidemiol 2007;60:34-42
Aaronson N et al. Qual Life Res 2002;11:193-205 Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
7. Questionnaire based outcome
measures
Flaws
‘floor’ and ‘ceiling’ effects Wamper KE et al.Acta Orthop 2010;81:703-7
Konan S et al.HSS J 2012;8:198-205
Misinterpretation Murray DW etal. JBJS(Br) 2007;89-B:1010-14
Cultural differences
Pain and function
Perception vs. true performance Fujita et al. Osteoarthrits Cartilage.2009;17:848-
55
Lavernia et al. J Arthroplasty;2012;27:1276-82 Clement ND et al.JBJS(Br);2011;93B:464-9
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
8. Questionnaire based outcome
measures
PROMs
Measure the patient’s perception of their abilities rather than
true performance. The former may not truly reflect function as it
is influenced by
Socioeconomic
Cultural and
Psychological factors
Fujita et al. Osteoarthrits Cartilage.2009;17:848-55
Lavernia et al. J Arthroplasty;2012;27:1276-82 Clement ND et al.JBJS(Br);2011;93B:464-9
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
10. Performance based outcome
measures
Performance based measure capture a different aspect of
function and used on their own or alongside PROMs, are more
likely to characterise fully a change in function than the use of
PROMs alone
Mizner RL et al. J Arthroplasty 2011;26:728-737
Stratford PW etal. Phy Ther;2006:86:1489-96
Startford PW et al. J Clin Epiodemiol.2009;62:347-52.
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
11. Other factors affecting the
outcomes
Confounders
Power
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
12. Discussion 1
PROMs have several advantages; they are easy to
administer and require no equipment and little
specialist training. However, they do not always
provide a true measure of culturally sensitive
function
Fazita et al. Osteoarthritis Cartilage.2009;17:848-55.
Uesugi Y et al. J Orthop Sci 2009;14:35-39.
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
13. Discussion 2
As a result of the ceiling effect, they have limitations when
the outcome is being studied in younger high demand
individuals
Wamper KE et al. Acta Orthop 2010;81703-7.
Tijssen M et al. BMC Musculoskeletal Disord 2011;12:117.
Beaupre LA et al. BMC Musculoskeletal Disord 2014;15:192
These disadvantages may hinder the usefulness of PROMs
for comparison of implants, procedures or surgical
approaches.
KonanS, Haddad FS Bone and Joint Journal 2014;96B:1431-5
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
14. Discussion 3
Performance based tasks address many of these disadvantages
which has proved difficult to identify with PROMs that are
currently available.
Haddad FS et al. AAOS annual meeting; San Francisco:2008
Cobb JP, Wilk AV, Lewis A, Amis A. AAOS aannual meeting: San
Francisco:2012
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
15. Discussion 4
There is a growing body of evidence that performance based
assessments can provide useful information over and above
that which is available from existing patient or physician
assessed questionnaires.
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
16. Discussion 5
Clinicians should be aware of the disadvantages
they offer and the limitations of commonly used
questionnaire bases tools.
Konan S, Haddad FS. Measuring function after hip and knee
surgery. Bone and joint Journal 2014;96B:1431-5.
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
18. Future direction
Compliance
50/60%
Can not validate the data
How to improve compliance ?
BOA
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
19. Patient satisfaction
In ULHT series - less than 10% not happy
Perception v/s Real outcome ( an issue with PROMs)
In TKR cases this figure can go up to 20%
Toms et al.Bone Joint J. 2014 Sep;96-B(9):1227-33)
Groin pain and activity related hip pain are problem in
small percentage of patintes (0.4 to 18.3%)
Swiss Med Wkly. 2014 Oct 8;144:w13974
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
20. PROMs data vs Quality
improvement
If you improve quality the data and outcome will be better
Ring fencing
Compliance
Hip school
Enhanced recovery programme
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
21. Revision rate high
Metal on metal
We should be using implant with long track record
For hip and knee replacement
Mr D Raj, Consultant Orthopaedic
Surgeon, Pilgrim Hospital, Boston
23. Fracture neck of femur: Implant
Cemented or uncemeted
hemiarthoplasty
Oxford
292/412
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
24. Outcome measures included: complications, re-operations
and mortality rates at two, seven, 30 and 365 days post-
operatively.
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
25. Comparable outcomes for the two stems were seen. There
were more intra-operative complications in
the uncemented group (13% vs 0%), but the cemented group
had a greater mortality in the early post-operative period (n
= 6). There was no overall difference in the rate of re-
operation (5%) or death (365 days: 26%) between the two
groups at any time post-operatively. This study therefore
supports the use of both cemented and uncemented stems of
proven design, with an ODEP rating of 10A, in patients
with an intracapsular fracture of the neck of the femur.
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
26. This study therefore supports the use of
both cemented and uncemented stems of proven design,
with an ODEP rating of 10A, in patients with an
intracapsular fracture of the neck of the femur.
Bone Joint J 2015;97-B:94-9. Oxford
(Exeter vs Corail)
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
27. There was no difference in the mortality rate between the
groups. There were significantly fewer complications in
the uncemented group, suggesting that the use of this stem
would result in a decreased rate of morbidity in these frail
patients. Whether this relates to an improved functional
outcome remains unknown
Bone Joint J. 2014 Mar;96-B(3):299-305
(Exeter / Corail)Keating, Edinburgh
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
29. Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
30. Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
31. Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
32. Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
33. sharon
Sharon – Participation rate –Compliance 80%
Pre op 80%
Pt response rate 66%
met the national average
Information, Expectation
Risk and benefit
CQC – risk Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
34. Rapid recovery programme
Ring fencing
Younger age group validity of PROMS COMPARISON
(14%)
Anxiety / depression
Mr D Raj, Consultant Orthopaedic
Surgeon Pilgrim Hospital, Boston
Editor's Notes
Good afternoon.
The extent and depth of health care data are growing at an ever increasing rate. These can answer a vast array of questions. However, an understanding of the purpose of the dataset used and the quality of the data collected are paramount to determine the reliability of the result obtained.
This afternoon session is dedicated to PROMS. I am going to give you a broader perspective about assessment and interpretation of the data obtained.
The accurate measure of outcome after hip and knee surgery is essential for both clinicians and researchers.
Surgeon reported outcome is valuable but lacks comparability which limits its usefulness.
Studies of interventions, prostheses or rehabilitation protocols need
Validated
Reproducible
And comparable
Outcome tools which can detect subtle changes in function and thereby gain international acceptance.
Broadly the outcome measures can be classified into
Subjective - which measures the patient’s own perception of outcome
Objective – measures may be assessment of function by another individual or measurement taken by an automated system or device ( i.e. a treadmill) or a radiological assessment.
A large number of questionnaire based outcome measures have been devised in recent years.
These may be subjective, objective or both.
Such questionnaires have a number of advantages. They may be
Self administered
Simple
And Cost effective
Many have well described properties including
Reproducibility
Reliability etc. as show on the slide.
However, these systems have inherent flaws. Most outcome scores have ‘floor’ and ‘ceiling’ effects. Cultural differences may limit their capacity to be applied worldwide, consequently, they have to be validated separately for use in different languages. This is important as 8% of English population have main language other than English and this is increasing. More so, in Boston, which is the East European capital of UK, as per the latest census report, it has more than 10% of east European population and this is ever so increasing
Some questions may be open to misinterpretation.
Most scoring system categories pain as a single category. However, it is often difficult to differentiate between pain and function, as they may influence each other; and this is specially true when two are not concordant
PROMS measure the patient’s perception of their abilities rather than true performance. The former may not truly reflect function as it is influenced by
Socioeconomic
Cultural and
Psychological factors
An alternative to PROMS and to the direct monitoring of performance is the assessment of the ability of a patient to complete directly observed tasks. These tools, known as performance based outcome measures, are observer assessed tasks that are qualified on the basis of timing, counting or distance.
They assess the individual’s true performance. Unlike measures of muscle strength or range of motion, they are not specific to body structure,, function or specific impairment.
There is increasing evidence that performance based measure capture a different aspect of function and used on their own or alongside PROMs, are more likely to characterise fully a change in function than the use of PROMs alone
When trying to link outcome to a unit, it is easy to arrive to a conclusin but if secondary factors are not looked at the data set, then the aseement may be wrong
Confounders: PROMs do not look into many confounders
1. Comorbiditeis – ASA garde, BMI of the patient, other joint involvement rheumatoid arthritis etc.
2. Age of the patient, socio economic status
3. Somewhat unintuitively, the statistical power of the data may be unduly great, such that even a minute clinical difference may become statistically significant.
4. It is also established that in those unit where there is a very effective rapid recovery programme, ring fencing, post op rehab protocol extended physo program, the PROMs outcome is better.
Take home message
Performance based tasks address many of these disadvantages which has proved difficult to identify with PROMs that are currently available
For instance, they have been used to show a difference between resurfacing and replacement in hip surgery ( better walking speed, stride length, stair negotiation and single leg stance
Despite a number of studies by which performance based functional tasks have been validated, their use has been limited by several factors.
In general, patient satisfaction remains the key determinant of success after an Hip or knee replacement: questionnaire based studies effectively represent the patients perception of their own outcome.
Performance based tasks need an observer, equipment and a dedicated assessment area, and may be difficult to incorporate into routine clinical follow up: they are also more time consuming to administer than PROMs.
