‘Total Hip Replacement and
Musculoskeletal disorder research’
Tosan Okoro
NWORTH Seminar
May 2012
Outline
• WCAT Trainee Trauma and Orthopaedics
• PhD commenced August 2009
• Work supported by BCUHB Small Grants
Scheme
The Evidence
• THR Indications 1
– Pain
– Loss of mobility i.e. function
• Functional limitations that persist after THR 2
– Reduced muscle strength and postural stability
– Reduced walking speed
– Reduced stair climbing ability
1
2
Trudelle-Jackson E et al. Arch Phys Med Rehabil 2004. 85;1056-1062
Brander VA et al. Clin Orthop 1997;Dec(345):67-78.
The Evidence
Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) physical
function score over time after total joint replacement between low and high baseline
function groups
Fortin et al. Arthritis Rheum 2002; 46 (12): 3327-3330
The Evidence
• Effects of poor function
– At 2 years after THR patients with low function 5x
more likely to require assistance for activities of
daily living (ADLs) than patients with high function 1
1. Fortin et al. Arthritis Rheum 2002; 46 (12): 3327-3330
Aims of study
To assess early home-based progressive resistance
training (PRT) after total hip replacement (THR)
?improves muscle strength and patient
function
vs.
‘routine’ physiotherapy
But what is routine physiotherapy after ‘THR’
• Ethics committee approval
• Focus Group
– 4 physiotherapists; minimum 5 years experience
– Pre-, Post-operative and continuing rehabilitation
themes discussed
• Questionnaire development
• Online survey of physiotherapists in the UK
– CSP
– National Joint Registry
European College of Sports Science (ECSS) Annual Congress, Liverpool, July 2011
‘Routine’ Physiotherapy
• Progressive resistance training
– 73% aware of it
prescribed by only 32%
• 74% of respondents did not refer patients for
further treatment on discharge
• Resubmitted to ‘Physiotherapy’ April 2012
European College of Sports Science (ECSS) Annual Congress, Liverpool, July 2011
Aims of study
To assess early home-based progressive resistance
training (PRT) after total hip replacement (THR)
?improves muscle strength and patient
function
vs.
‘routine’ physiotherapy
Design
• Prospective single blinded RCT.
Ethical approval Jan 2010
• Stratification with age + gender
• Pilot Study
• NWORTH input
1 outcomes
• Maximal voluntary contraction of quadriceps
muscle
• Objective measures of physical function
– Timed up and go
– 6 minute walk
– Gait speed
– Stair climbing performance
– Sit to stand score
Objective measures
6 minute walk test
(6MWT)
Sit to stand
(ST)
Gait speed (GS)
Timed up and go
(TUG)
Stair Climb
performance
(SCP)
Sample size (n=10 per group)
• Maximal voluntary force in quadriceps muscle
• 10% improvement with exercise relative to
controls
• 80% power; alpha 0.05
• n=50 patients to recruit
Collaborations
Prof Clare Stewart, MMU,
Manchester
Muscle Physiology
Recruitment
So far…
Surgical
Experience
Gender
Living
Situation
? Influence Function and Perceived Control in Patients
awaiting Total Hip Replacement Surgery
European Health Psychology Society
Annual congress, Crete, 2011
European Health Psychology Society Annual
congress, Crete, 2011
Gender
Females > Males
RLOC INT (p=0.075)
Living alone > With Partner
History of previous
surgery
TPB PBC (p=0.085)
RLOC INT (p=0.073)
No effect
WOMAC PF (p=0.059)
Preoperative
Function
RLOC
TPB PBC
So what?
• ? Change locus of control to influence postoperative outcome
• Assess influence of control cognitions on
function post-operatively
So far…
6 minute walk test
(6MWT)
Sit to stand
(ST)
Gait speed (GS)
Timed up and go
(TUG)
Stair Climb
performance
(SCP)
British Hip Society 2012
British Hip Society 2012
Objec ve func on of cohort compared to normal
popula on
100
80
60
Func onal deficit
Expected
func on %
Observed objec ve
func on
40
20
0
TUG
KEY:
TUG(s)
ST
6MWT (m)
SCP(s)
GS (m/s)
6MWT
GS
ST
Timed up and Go in seconds
Number of sit to stand performed from a chair in 30 seconds
6 minute walk test in metres
Stair climb performance in seconds
Gait speed in metres/second
Oxford Hip Score Correla ons
1
0.345
0.247
0.264
6MWT
GS
R value 0
TUG *
ST *
-0.327
SCP *
-0.33
-1
KEY:
*
TUG(s)
ST
6MWT (m)
SCP(s)
GS (m/s)
P<0.05
Timed up and Go in seconds
Number of sit to stand performed from a chair in 30 seconds
6 minute walk test in metres
Stair climb performance in seconds
Gait speed in metres/second
rWOMAC PF Correla ons
1.0
0.51
0.47
ST *
6MWT *
0.49
R value 0.0
TUG *
-0.50
SCP *
GS *
-0.43
-1.0
KEY:
rWOMAC PF
*
TUG(s)
ST
6MWT (m)
SCP(s)
GS (m/s)
Reduced Western Ontario and McMasters University Osteoarthritis personal function scale
P<0.05
Timed up and Go in seconds
Number of sit to stand performed from a chair in 30 seconds
6 minute walk test in metres
Stair climb performance in seconds
Gait speed in metres/second
So what?
• rWOMAC PF better than OHS as a measure of
ADLs and objectively measured physical
disability
• Use of OHS as measure of impairment not
appropriate
So far…
• Mental Health- Distress and Risk Assessment
Method (DRAM)
Main CJ, Wood PL, Hollis S, Spanswick CC, Waddell G. The Distress and Risk Assessment Method.
A simple patient classification to identify distress and evaluate the risk of poor outcome.
Spine (Phila Pa 1976) 1992 Jan;17(1):42-52.
British Hip Society 2012
* p<0.05
Effect of DRAM on Oxford Hip Score
Effect of DRAM on reduced WOMAC
function scale (rWOMAC PF)
CONSORT
FLOWCHART
Data analysis in
progress
Acknowledgements
Supervisors
A Lemmey
P Maddison
J G Andrew
Musculoskeletal Research Group
Orthopaedic Department
Collaborators
Physiotherapists
• Thank you