PainSci summary of Rathleff 2014?This page is one of thousands in the PainScience.com bibliography. It is not a general article: it is focused on a single scientific paper, and it may provide only just enough context for the summary to make sense. Links to other papers and more general information are provided at the bottom of the page, as often as possible. ★★★★☆4-star ratings are for bigger/better studies and reviews published in more prestigious journals, with only quibbles. Ratings are a highly subjective opinion, and subject to revision at any time. If you think this paper has been incorrectly rated, please let me know.
This review of 24 of the highest quality studies available found that patellofemoral pain and hip weakness are certainly associated, but weakness is not the cause of the pain — indeed, it’s probably the other way around. Correlations are easy to find, but causality can be tricky to nail down: you have to study runners before they develop pain (a prospective study design), and then wait and see who develops it. Experiments of that kind (Thijs 2011) andhave shown that hip strength was the same in runners regardless of whether or not they eventually ended up in pain.
(Was isometric strength too “simplistic” a measure to be meaningful? Maybe. But isometric strength usually doesn’t develop in isolation except in people who train isometrically, and when measured in study subjects like these I imagine it correlates reasonably well with dynamic strength.)
original abstract†Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
OBJECTIVE: To evaluate and synthesise the literature on hip strength among patients with patellofemoral pain (PFP) to address the following:
- differentiate between hip strength as a risk factor and associated deficit in PFP;
- describe hip strength in men and women with PFP across different age ranges;
- investigate the effects of hip strengthening on biomechanical knee variables associated with PFP development.
METHODS: MEDLINE, CINAHL, Web of Science, SportDiscus and Google Scholar were searched in November 2013 for studies investigating hip strength among patients with PFP. Two reviewers independently assessed papers for inclusion and quality. Means and SDs were extracted from each included study to allow effect size calculations and comparisons of results.
RESULTS: Moderate-to-strong evidence from prospective studies indicates no association between isometric hip strength and risk of developing PFP. Moderate evidence from cross-sectional studies indicates that men and women with PFP have lower isometric hip musculature strength compared to pain-free individuals. Limited evidence indicates that adolescents with PFP do not have the same strength deficits as adults with PFP.
CONCLUSIONS: This review highlights a possible discrepancy between prospective and cross-sectional research. Cross-sectional studies indicate that adult men and women with PFP appear to have lower hip strength compared to pain-free individuals. Contrary to this, a limited number of prospective studies indicate that there may be no association between isometric hip strength and risk of developing PFP. Therefore, reduced hip strength may be a result of PFP rather than the cause.
- PS Does Hip Strengthening Work for IT Band Syndrome? — The popular “weak hips” theory is itself weak
- “Is hip muscle weakness a predisposing factor for patellofemoral pain in female novice runners? A prospective study,” Youri Thijs, Els Pattyn, Damien Van Tiggelen, Lies Rombaut, and Erik Witvrouw, American Journal of Sports Medicine, 2011.
One article on PainScience.com cites Rathleff 2014 as a source:
- PS Save Yourself from Patellofemoral Pain Syndrome! — Patellofemoral pain syndrome (aka runner’s knee) explained and discussed in great detail, including every imaginable self-treatment option and all the available scientific evidence
This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:
- A Bayesian model-averaged meta-analysis of the power pose effect with informed and default priors: the case of felt power. Gronau 2017 Comprehensive Results in Social Psychology.
- The neck and headaches. Bogduk 2014 Neurol Clin.
- Agreement of self-reported items and clinically assessed nerve root involvement (or sciatica) in a primary care setting. Konstantinou 2012 Eur Spine J.
- Effect of NSAIDs on Recovery From Acute Skeletal Muscle Injury: A Systematic Review and Meta-analysis. Morelli 2017 Am J Sports Med.
- Association of Spinal Manipulative Therapy With Clinical Benefit and Harm for Acute Low Back Pain: Systematic Review and Meta-analysis. Paige 2017 JAMA.