“Low Back Pain Remains Public Health Crisis!”
According to the Bone and Joint initiative, musculoskeletal (MSK) disorders are the leading cause of physical disability in the world. A 2018 Gallup study found that over 60% of US adults report having experienced back or neck pain severe enough to require care from a healthcare provider at some point in their lives, with 25% seeking such care within the past year. The most common musculoskeletal condition reported is low back pain. Low back pain is also one of the most frequent reasons that active duty military personnel seek medical care. The burden of low back pain is made worse by the fact that many treatments included under the umbrella of usual medical care, such as NSAIDs, steroid injections, spinal surgery, and opioids, do not significantly decrease pain and may result in serious side effects. Spurred on primarily by the resultant opioid crisis, many government and private organizations, including the FDA, the Joint Commission, and the American College of Physicians are now recommending the use of non-drug, non-surgical therapies for chronic pain, including low back pain. Chiropractic care and/or spinal manipulation delivered by doctors of chiropractic (DCs) is one of these recommendations.
DCs are licensed in all 50 states as autonomous clinicians with specific training and expertise in the treatment of musculoskeletal disorders, including low back pain. Chiropractors do not prescribe drugs or perform invasive interventions. Primary interventions delivered by DCs include spinal manipulation, physiotherapy treatments, exercise, patient education, and other lifestyle management approaches. Gallup studies show that over half of US adults have received chiropractic care, with approximately 15% reporting a visit within the past year.
Systematic reviews have evaluated the effectiveness of spinal manipulation over the past two years. In general, findings from these studies indicate a low to moderate treatment effect. However, the state of the evidence is often rated as low, with authors calling for larger studies of higher quality. In addition, few clinical trials have been conducted on chiropractic in the military. The clinical trial “Effect of Usual Medical Care Plus Chiropractic Care vs Usual Medical Care Alone on Pain and Disability Among US Service Members with Low Back Pain,” recently published in the JAMA Network Open,1 was designed to address these gaps.
This multi-site, pragmatic, comparative effectiveness study with adaptive allocation took place at: Walter Reed National Military Medical Center, Bethesda, Maryland; Naval Hospital Pensacola, Florida; and Naval Medical Center, San Diego, California. A total of 806 active duty military personnel with low back pain, aged 18 to 50 years, were assessed for eligibility in the study. Of these, 750 participants, 250 at each military site were subsequently allocated to receive either usual medical care (UMC) alone (n = 375) or usual medical care plus chiropractic care (UMC+CC; n = 375).
Because this was a pragmatic study design, investigators did not specify treatment protocols in either group, allowing the treating clinicians to determine procedures and the number of healthcare visits required. UMC involved therapies prescribed or recommended by medical providers for the participant’s low back pain, including prescription medications, physical therapy, or specialist referral. Chiropractic care included some combination of spinal manipulation, manipulation to other joints of the body, physical therapy modalities, and self-care recommendations.
Patient-reported outcomes were assessed at baseline, and 2, 4, 6 (primary endpoint) and 12 weeks using online self-report questionnaires. Primary outcomes included average LBP intensity during the prior week as reported via a 0- to 10-point numerical rating scale (NRS and LBP-related functional disability using the Roland Morris Disability Questionnaire). Secondary outcomes included a responder analysis, pain medication use, global LBP improvement, and patient satisfaction.
Details of the statistical analysis plan are included in the published paper.1 Briefly, an intention-to-treat model was used and, as stated in the paper, “all observed data were used in the analyses and regression models included terms for time, site, group, site-by-group, time-by-group and site-by-time-by-group interactions, adjusted for sex, age, pain duration and worst pain during the past 24 hours.”1
Overall, researchers found mild to moderate short-term treatment benefits in LBP intensity (mean difference: -1.1; 95% CI, -1.4 to – 0.7) and physical disability (mean difference: 2.2; 95% CI, -3.1 to -1.2) in favor of those receiving chiropractic care in addition to usual medical care. These findings were statistically significant and met established thresholds for moderate clinical effects based on American College of Physicians and American Pain Society guidelines. Site-specific results varied somewhat but were consistent with overall study results. Secondary outcomes followed a similar pattern. No related serious adverse events were reported in either group. Side effects attributed to chiropractic care consisted primarily of transient muscle and/or joint stiffness.
Discussion: In Practice
These findings have the potential to impact clinical practice by strengthening the scientific literature regarding the use of chiropractic care in patients with LBP in the military and beyond. Issues such as small sample sizes and heterogeneity in terms of participant populations, outcome measures, treatment protocols, and study findings have been identified in previous systematic reviews. As a result, the state of the evidence for standard treatment has been consistently rated as low for both acute and chronic LBP. This study sample of 750 participants is the largest trial evaluating UMC+CC versus UMC alone using a standardized protocol. The inclusion of 250 participants at each site allowed investigators to address heterogeneity in both research methods and patient characteristics.
As is common among all studies of this non-specific condition, LBP diagnoses in this trial were not confirmed against a gold standard, creating a potential opportunity for bias. Further, because this was a pragmatic trial of a hands-on manual therapy, participants were not masked to their treatment group, eligibility criteria were broad, and a range of interventions was used. However, these attributes also contribute to the generalizability of study results.
This large multi-site pragmatic comparative effectiveness study found that adding chiropractic care to usual medical care resulted in better participant outcomes. By addressing weaknesses inherent in previous studies and providing further evidence to support LBP management that includes the integration of chiropractic care within a multidisciplinary health setting, these findings provide additional support for the use of chiropractic care as part of a multidisciplinary approach for patients suffering from low back pain.