RESUMEN
OBJECTIVE: The objective of the present study was to assess the degree of pain relief obtained by applying infrared (IR) energy to the low back in patients with chronic, intractable low back pain. METHODS: Forty patients with chronic low back pain of over six years' duration were recruited from patients attending the Rothbart Pain Management Clinic, North York, Ontario. They came from the patient lists of three physicians at the clinic, and were randomly assigned to IR therapy or placebo treatment. One patient dropped out of the placebo group; as a result, 21 patients received IR therapy and 18 received placebo therapy. The IR therapy was provided by two small, portable units in a sturdy waistband powered by small, rechargeable batteries made by MSCT Infrared Wraps Inc (Canada). These units met safety standards for Food and Drug Administration portability, and are registered with the Food and Drug Administration as a therapeutic device. The unit converted electricity to IR energy at 800 nm to 1200 nm wavelength. The treated group received IR therapy. The placebo group had identical units, but the power was not connected to the circuit-board within the IR pad. Patients attended seven weekly sessions. One baseline and six weekly sets of values were recorded. The principle measure of outcome was pain rated on the numerical rating scale (NRS). The pain was assessed overall, then rotating and bending in different directions. RESULTS: The mean NRS scores in the treatment group fell from 6.9 of 10 to 3 of 10 at the end of the study. The mean NRS in the placebo group fell from 7.4 of 10 to 6 of 10. CONCLUSION: The IR therapy unit used was demonstrated to be effective in reducing chronic low back pain, and no adverse effects were observed.