Does manual therapy meaningfully change quantitative sensory testing and patient reported outcome measures in patients with musculoskeletal impairments related to the spine?: A ‘trustworthy’ systematic review and meta-analysis

ABSTRACT

Objectives

To perform a ‘trustworthy’ systematic review (SR) with meta-analysis on the potential mechanisms of manual therapy used to treat spinal impairments.

Design

SR with meta-analysis

Literature Search

Articles published between January 2010 and October 2022 from CENTRAL, CINAHL, MEDLINE, PubMed, ProQuest, and PEDro.

Methods

This SR included English-language randomized clinical trials (RCTs) involving manual therapy to treat spinal impairments in adults. The primary outcome was pressure pain thresholds (PPTs). To synthesize RCTs with high confidence in estimated effects using the GRADE, RCTs with questionable prospective, external, and internal validity, and high risk of bias (RoB) were excluded.

Results

Following title and abstract screening, 89 full-text RCTs were reviewed. Twenty-two studies included the criteria of interest. Sixteen were not prospectively registered, two contained discussion/conclusions judged to be inconsistent with the registry, and one was rated as having a high RoB. Three studies met the inclusion criteria; heterogeneous interventions and locations for PPT testing prevented synthesis into practice recommendations. The two studies with high confidence in estimated effects had small effect sizes, and one study had confidence intervals that crossed zero for the outcome measures of interest.

Discussion

Standardized PPT testing, as a potential measure of centrally mediated pain, could provide clues regarding the mechanisms of manual therapy or help identify/refine research questions.

Conclusion

High-quality RCTs could not be synthesized into strong conclusions secondary to the dissimilarity in research designs. Future research regarding quantitative sensory testing should develop RCTs with high confidence in estimated effects that can be translated into strong recommendations.

KEYWORDS:

• Central nervous system sensitization
• prospective studies
• manipulation
• pressure pain threshold
• spinal

Acknowledgements

We thank Nick Wharton, MLIS of the University of Hartford, for his assistance in developing the search strategy used to identify the systematic reviews that met the inclusion criteria for this study.

Disclosure statement

The primary author Sean P. Riley is a Deputy Editor at the Journal of Manual and Manipulative Therapy (JMMT). He also contributes to the Duke Center for Excellence in Manual and Manipulative Therapy. The authors’ otherwise report that there are no competing interests to declare.

Author contributions

The primary author, Sean Riley, coordinated the development of the research questions and protocol with his coauthors. Brian Swanson identified which search engines would be used and developed the search strategies for each with the assistance of a professional librarian. Margaret Hofbauer ensured that the full-text articles of interest were retrieved and uploaded into Covidence. Daniel Flowers and Stephen Shaffer screened the identified randomized clinical trials to determine if they met the inclusion and exclusion criteria. Richard Liebano was responsible for the interpretation of the data, recognizing gaps in knowledge, and identifying a potential path forward to answer the questions related to the mechanisms of manual therapy. All authors were involved in drafting and revising the protocol for important intellectual content and agreed to be accountable for the accuracy and integrity of the work.

Support

Sources

The resources for gathering and inputting the randomized clinical trials into Covidence were provided by the University of Hartford, College of Education, Nursing, and Health Care Professions.

Sponsor

The sponsors for this series of living systematic reviews are the Center of Excellence in Manual and Manipulative Therapy at Duke University and the University of Hartford.

Role of sponsor or funder

The funder, sponsor, and institutions were not involved in developing this systematic review.

SUPPLEMENTARY MATERIAL

Supplemental data for this article can be accessed online at https://doi.org/10.1080/10669817.2023.2247235

Additional information

Funding

The author(s) reported there is no funding associated with the work featured in this article

Notes on contributors

Sean P. Riley

Dr. Sean P. Riley is an Assistant Professor in the Doctor of Physical Therapy Program and a faculty member in the orthopaedic physical therapy residency at the University of Hartford. He is board certified in orthopaedics and a Fellow of the American Academy of Orthopaedic Manual Physical Therapists. Dr. Riley’s research interests include symptom modification approaches to evaluating and treating neuromusculoskeletal disorders, evidence-based practice, research methodology, and clinical reasoning.

Brian T. Swanson

Dr. Brian T. Swanson is an Associate Professor at the University of Hartford. He serves as Chair of the Department of Rehabilitation Sciences, Director of the Doctor of Physical Therapy Program, and co-director of the University of Hartford/HHCRN orthopedic physical therapy residency program. He is board certified in orthopaedics and a Fellow of the American Academy of Orthopaedic Manual Physical Therapists. Dr. Swanson’s research interests include validating tests and measures in orthopedic manual physical therapy, developing a further understanding of the mechanisms of manual physical therapy interventions, and evidence-based practice/research methodology.

Stephen M. Shaffer

Dr. Stephen M. Shaffer is a residency and fellowship-trained clinical specialist, educator, and scientist with nineteen years of experience in the physiotherapy profession. He has worked primarily in orthopaedic settings, is an Adjunct Professor at the University of Hartford, and is a Fellow of the American Academy of Orthopaedic Manual Physical Therapists and the Canadian Academy of Manipulative Physiotherapy. Dr. Shaffer has co-authored numerous peer-reviewed scientific papers and has presented at local, state, national, and international venues.

Daniel W. Flowers

Dr. Daniel W. Flowers is an Assistant Professor in the Doctor of Physical Therapy and PhD in Rehabilitation Sciences Programs at LSU Health Shreveport. He also serves as program director of the orthopaedic residency. He is board-certified in orthopaedic physical therapy. His research interests include modifying the gait impairments of patients with knee osteoarthritis, post-traumatic rehabilitation, and educational outcomes of physical therapy students.

Margaret A. Hofbauer

Margaret A. Hofbauer is a second-year physical therapy doctorate student at the University of Hartford. She is the class president and is actively involved within the program. She aids in the Scientific Inquiry class for the first year DPT students as a teaching assistant. Margaret completed her personal research investigating communication methods for individuals with Alzheimer’s Disease for the Honors Program in 2021. Her research interests include orthopaedics, neurologic degenerative disorders, and geriatrics.

Richard E. Liebano

Dr. Richard E. Liebano is an Associate Professor in the Department of Rehabilitation Sciences at the University of Hartford. He has published three books, 14 book chapters, and co-authored numerous peer-reviewed scientific papers. Dr. Liebano’s research interests include the mechanisms and effectiveness of biophysical agents and other physical therapy interventions to reduce pain and improve tissue healing.