To determine the concurrent longitudinal and cross-sectional relationships of the mechanism of action of SM as seen in changes in CPM and clinical outcomes of pain, disability, and perceived recovery in adults with mechanical CNP.
Within a week of meeting flier QR-code eligibility criteria, 31 participants [median age (interquartile range) 28 (26, 38), median body mass index or BMI 24.9 (23.2, 26.9)] with CNP who remained eligible received one session of cervical SM. Blinded to all outcomes, the principal investigator provided SM totaling 10 minutes of posterior and anterior pressures [random order (www.randomizer.com) techniques application was revealed after opening a sealed envelope]. Before and after SM, research assistants assessed the CPM [testing stimulus: pain pressure threshold or PPT from averaged values of more/painful side C3/4 articular pillars, infraspinatus muscle, tibialis anterior (sequence per www.randomizer.com was revealed after opening a sealed envelope); conditioning stimulus: cold pressor test (CPT) of non-/less painful hand at 12 degrees Centigrade for 2 minutes]. CPM formula= (PPT post-CPT minus PPT pre-CPT)/PPT pre-CPT, X 100. (+) indicates normal CPM, (-) impaired CPM. CPM change were analyzed for their longitudinal association with three self-report measures - pain (Numeric Pain Rating Scale), function (Neck Disability Index), and global perceived recovery (GPR) at baseline (reference), two days, two weeks, and four weeks post-SM. Research assistants collected follow-up outcome measures remotely. Longitudinal analysis using mixed effect modeling was performed with each participant entered as a random factor, sex and time as fixed factors, CPM and demographic factors as covariates. Cross-sectional analysis using simple regressions were also performed.
In the cross-sectional regression analysis at the 2-week follow-up time point, the CPM changes were significantly associated with GPR during univariate and multivariate analyses (Holm-Bonferroni adjusted) [coefficient (SE)/p-value: 0.02 (0.01)/0.00 and 0.02 (0.01)/0.01, respectively], holding baseline GPR constant, adjusted for age, sex, and BMI.
However, the longitudinal mixed effect modeling ANOVA showed that CPM change, has no significant effects on improvements (2-days through 4-weeks) in NPRS, NDI and GPR, when adjusted for age, sex, and BMI.
Post-SM, CPM changes were associated with perceived recovery at the 2-week follow-up time point.
Post-SM, the immediate CPM changes underpinned/moderated the discharge outcome at 2-week.
spinal mobilization
mechanism of action
