Efficacy and safety of thread embedding acupuncture for chronic low back pain: a randomized controlled pilot trial

This randomized controlled pilot study investigated an innovative technique called thread embedding acupuncture (TEA) for the treatment of chronic low back pain. Chronic low back pain affects up to 85% of the population at some point in life and represents a significant therapeutic challenge, leading many patients to seek complementary therapies such as acupuncture. TEA is a variation of traditional acupuncture that uses absorbable threads (polydioxanone) inserted into specific points, where they remain for weeks, providing continuous stimulation. The study was conducted at the Korean Hospital of Daegu, South Korea, with 40 adult participants who had chronic low back pain for at least 6 months, diagnosed by imaging studies.

Participants were randomized into two groups: the TEA group received 4 treatment sessions (one every 2 weeks), with insertion of 39 absorbable threads at 17 specific locations on the back and abdomen; the control group received traditional acupuncture with electrical stimulation, totaling 16 sessions (twice per week) at 19 acupuncture points. The methodology followed rigorous standards with blinded assessors and adequate randomization. Outcomes were measured using the Visual Analog Scale (VAS) for pain, the Short-Form McGill Pain Questionnaire (SF-MPQ), and the Oswestry Disability Index (ODI). Assessments occurred at baseline and at 2, 4, 6, 8, and 10 weeks.

Both groups showed statistically significant improvements in all parameters over time. On the VAS pain scale, the TEA group decreased from 6.04 to 2.34 points, while the acupuncture group decreased from 5.91 to 2.79 points. An important difference was observed on the Disability Index (ODI), where there was a significant interaction between groups and time, suggesting that TEA may provide better functional improvement compared with traditional acupuncture at week 8. As for safety, no serious adverse events were recorded.

Only two participants in the acupuncture group reported mild itching in the lumbar region. Laboratory tests performed before and after treatment remained within normal limits, including specific tests to detect possible infection in the TEA group. The adherence rate was excellent (100% of participants who completed), and only 4 participants dropped out for reasons unrelated to the treatment. The clinical implications suggest that TEA may be an interesting alternative to traditional acupuncture, especially considering that it requires significantly fewer sessions (4 vs 16) while maintaining similar efficacy.

This could reduce costs and facilitate access to treatment. The proposed mechanism involves continuous stimulation of the core muscles and ligaments around the spine through the absorbable threads, which dissolve slowly, stimulating collagen fiber formation. As limitations, the study acknowledges the small sample size typical of pilot studies, the inability to blind patients and providers, and the need for further research on mechanisms of action and long-term safety.