Systematic Review on the Benefits and Harms of Spinal Manipulative Therapy for Acute Low Back Pain

BACKGROUND:
Lifetime prevalence estimates of low back pain exceed 50%, but none of the therapies used for acute back pain has been established as superior to the others. Treatments include analgesics, muscle relaxants, exercises, physical therapy, heat, and spinal manipulative therapy (SMT), among others. There have been multiple systematic reviews on SMT, but with differing conclusions. As new trials continue to be published, and given the differences in findings among previous studies, this systematic review was conducted to provide updated estimates of the effectiveness and harms associated with SMT compared with other non-manipulative therapies for adults with acute low back pain. Investigators searched databases (i.e., MEDLINE, Cochrane Database of Systematic Reviews, EMBASE) from January 1, 2011 through February 6, 2017 for studies in which SMT was given alone or as part of a "package" of therapies for patients with lower back pain for six weeks or less. From this search, 26 articles met inclusion criteria for an analysis of SMT's effectiveness (primary outcomes were pain and functional status), while 8 articles were used in an analysis of adverse events. Many of these articles described randomized controlled trials (RCTs).

FINDINGS:

• Spinal manipulative therapy was associated with statistically significant benefits in both pain (15 RCTs with moderate quality evidence) and function (12 RCTs with moderate quality evidence) – of an average modest magnitude at up to six weeks.
• Minor transient adverse events (i.e., increased pain, muscle stiffness, and headache) were reported in more than half of the patients (67%) in the large case series.
• Heterogeneity in study results was not explained by type of clinician performing SMT, type of manipulation, study quality, or whether SMT was given alone or in conjunction with other therapies, although there was a limited ability to detect such associations.

IMPLICATIONS:

• The most advantageous area for further research is likely to be assessing the role of patient selection and type of SMT on explaining heterogeneity in treatment effects.

LIMITATIONS:

• More studies were classified as low quality than high quality, but high-quality studies tended to report larger benefits. The studies reporting the largest benefits were three studies that used clinical criteria to select patients as more likely to benefit from SMT.
• Some studies did not describe the manipulation in sufficient detail to allow application in practice.

AUTHOR/FUNDING INFORMATION:
This review is part of a larger review funded through VA HSR&D/QUERI's Evidence-based Synthesis Program (ESP). Drs. Paige, Miake-Lye, and Shekelle, and Ms. Beroes are part of HSR&D/QUERI's ESP Center, West Los Angeles, CA.

Paige N, Miake-Lye I, Booth M, Beroes J, Mardian A, Dougherty P, Branson R, Tang B, Morton S, and Shekelle P. Association of Spinal Manipulative Therapy with Clinical Benefit and Harm for Acute Low Back Pain. JAMA. April 11, 2017;317(14):1451-60.