Magnetic pulses may ease low back pain, on thin evidence

Low back pain is one of the most common reasons people seek treatment, and the menu of non-drug options keeps growing. Repetitive peripheral magnetic stimulation, or rPMS, delivers magnetic pulses to muscles and nerves in the body rather than the brain, and has been proposed as a painless, non-invasive way to reduce pain and restore function. Before a treatment like this earns a place in rehabilitation, the scattered trials testing it need to be pulled together to see whether the apparent benefits survive pooling.

The reviewers systematically searched PubMed, the Physiotherapy Evidence Database, Embase, the Cochrane Library and Web of Science from inception to November 25, 2022 for randomised controlled trials of rPMS in people with low back pain, compared against sham stimulation or other control treatments. From 733 studies identified, 6 randomised trials with 139 participants qualified. Two researchers independently screened, extracted and quality-checked the data, assessing methodological quality with the Physiotherapy Evidence Database score and grading the certainty of each outcome.

Compared with sham stimulation or other therapy, rPMS reduced pain intensity by 1.89 points on a visual analogue scale, a finding the reviewers graded as very low-quality evidence. Functional disability also improved, with scores on the Oswestry Disability Index falling by 8.39 points, graded low-quality evidence. Kinesiophobia, the fear of movement that often keeps people with back pain inactive, showed no statistically significant difference between groups. In short, two of the three outcomes favoured the treatment, but none of the evidence rose above low quality.

This is the familiar early-stage picture for a newer physical therapy: consistent-looking benefits across a tiny evidence base that cannot yet rule out bias or chance. The pooled sample of 139 people is small by any standard, and the trials varied in their protocols and comparators. The null result on fear of movement suggests any benefit works through the body rather than through reassurance, but that reading is speculative. Larger, better-designed trials will decide whether rPMS earns a routine place in back pain care.

If you deal with low back pain and encounter rPMS at a physiotherapy or rehabilitation clinic, this review gives a reason for cautious interest rather than confidence. The pooled data point towards less pain and better function, but the reviewers' own grading of very low to low quality means the true effect could be considerably smaller. Nothing here suggests harm, and nothing here suggests it addresses the fear of movement side of back pain.