1. Proximal muscle rehabilitation in patellofemoral pain: a systematic review and meta analysis
Simon Lack1, Christian Barton1-4, Oliver Graham Sohan1, Kay Crossley5, Dylan Morrissey1
1Centre for Sports and Exercise Medicine, Queen Mary University of London, United Kingdom
2Complete Sports Care, Melbourne, Australia
3Pure Sports Medicine, London, United Kingdom
4Lower Extremity Gait Studies, Health Sciences, La Trobe University, Bundoora, Australia
5School of Health and Rehabilitation Sciences, University of Queensland, Australia

2. Background
Patellofemoral pain (PFP) is common - prevalence of 3-20% in active populations
In individuals with PFP, impaired
hip muscle strength
hip function
lateral trunk strength
Interventions to target proximal deficits have been investigated exploring effect on pain, function and mechanisms
Boling et al. 2010; Thijis et al. 2011; Noehren et al. 2013; Prins et al. 2009;
Lankhorst et al. 2013; Rathleff et al. 2014; Barton et al. 2013; Cowan et al. 2008

3. Aims
Evaluate the effects of proximal muscle rehabilitation for patients with PFP
Compare the effects of various rehabilitation protocols
Identify the potential mechanism of action

4. Methods Search of 4 databases for PEDRO scale with SMDs categorised as
Randomised clinical trials and cohort studies
evaluating proximal muscle rehabilitation programmes
Hip ± lumbopelvic musculature exercise programme
PEDRO scale with SMDs categorised as
small (≤0.59)
medium (0.60–1.19)
large (≥1.20)
*Hume et al. 2008; van Tulder et al. 2003

5. Why change the title?
Concerns that ‘strengthening’ being used generically
Divided in to
Strength (≥70% 1 RM)
Strength Endurance (30-70% 1RM)
Neuromuscular (≥20 repetitions, <30% 1RM)
Power (85-100% 1RM or 0-60% 1RM at explosive velocity)
Limiting clinical applicability of findings
All included studies assessed “Reviewers interpretation of actual exercise aim”

6. Results – Exercise analysis
14 studies met the inclusion criteria – 7 HQ and 7 LQ, 11 RCT, 3 cohort

7. Author
Stated Exercise Aim (Title)
Method Exercise Aim (Within Text)
Reviewers Interpretation of Actual Exercise Prescription
Nakagawa et al.
Strength NM
Ismail et al.
Strength/Endurance
Fukuda et al.
Razeghi et al.
Dolak et al.
Ferber et al.
Khayambashi et al.
Baldon et al.
NM/Strength
Avraham et al.
Unclear
Tyler et al.
Not Stated
Str/End/NM/Power
Earl & Hoch

8. Results – Pain & Function
Proximal rehabilitation compared with Control
Short Term
Pain
SMD 2.80
95% CI:
Very limited evidence of large effect
Function
SMD 2.88
95% CI:
Very limited evidence

9. Results – Pain & Function
Proximal rehabilitation compared with Quadriceps rehabilitation
Short Term
Pain
SMD 0.36
95% CI:
Moderate evidence of small effect
Function
SMD 0.18
95% CI:
No difference
Medium Term
SMD 1.07
95% CI:
Strong evidence of medium effect
SMD 0.87
95% CI:
Hypothesis of no effect for short term function – quad deficits identified in PFP – correction of any deficit proximal or quads results in improvement

10. Results – Pain & Function
Proximal + Quadriceps compared with Quadriceps rehabilitation
Short Term
Pain
SMD 0.55
95% CI:
Strong evidence of small effect
Function
SMD 0.42
CI 95%: 0.03 to 0.81
Medium Term
SMD 1.36
95% CI:
Moderate evidence of large effect
SMD 1.32
95% CI: 0.75 to 1.89
Longer Term
SMD 2.99
95% CI: 2.16 to 3.83
Limited evidence of large effect
SMD 2.65
95% CI: 1.86 to 3.43

11. Results - Mechanisms
Proximal rehabilitation - compared with – Controls
Isometric hip abduction strength (limited evidence of large effect)
Knee valgum variability (very limited evidence of large effect)

12. Results - Mechanisms
Proximal rehabilitation – compared with – Quadriceps rehabilitation
No difference in all measures of isometric hip strength (moderate evidence)
trunk endurance and hip abductor & knee extensor torque (limited evidence of large to medium effect)

13. Results - Mechanisms
Proximal + Quadriceps rehabilitation - compared with - Quadriceps rehabilitation
No difference in all measures of isokinetic and isometric hip strength (limited to very limited evidence)

14. Conclusions Strong-moderate evidence - reduce pain + improve function
proximal rehabilitation in isolation
in combination with quadriceps rehabilitation
Incorporate proximal exercise in management of PFP
Clarity regarding exercise programme design needed
Further work is required to identify the most effective rehabilitation protocol