160 patients with acute or exacerbations of chronic low back pain (LBP) presenting for chiropractic and rehabilitation care will be randomized to one of two conditions: an M-Stim pain relief belt device incorporating 8 patterns of vibration motors (and optional heat, cold, and pressure) delivered through a sculpted metal plate; or a 4-lead TENS unit with 8 channels of stimulation and adjustable intensity. Patients will be blinded to the hypothesis-driving intervention. They will be prompted daily by a Qualtrics text link to a secure data recording site collecting analgesic use and treatments, including opioid brand, dose, pill number, and source, and pain data, then weekly for 3 months (acute pain) or 6 months (chronic).