Impact of Intramuscular Electrical Stimulation on Multifidus Muscle Function in Chronic Low Back Pain: A Randomized Controlled Trial.

Researchers investigated whether inserting acupuncture needles into the multifidus muscle (a deep back stabilizer) and applying electrical stimulation could improve chronic low back pain better than standard physical therapy. In this 6-week study, 29 adults with chronic low back pain were divided into two groups. The control group received standard care including TENS (surface electrical stimulation), trigger point therapy, and exercise. The experimental group received the same treatments but with intramuscular electrical stimulation (IMES) through acupuncture needles guided by ultrasound instead of TENS. The needles delivered electrical current directly into the multifidus muscle to activate it more effectively.

The IMES group showed significantly better results in several areas: reduced muscle tension, improved blood flow to the muscle, higher pain thresholds, lower pain ratings, better range of motion, and improved balance. These improvements were maintained four weeks after treatment ended. Interestingly, muscle stiffness and maximum strength didn't change in either group, suggesting the benefits came from improved muscle function rather than simply building strength.

For patients considering acupuncture for chronic low back pain, this study suggests that combining needle insertion with electrical stimulation may offer additional benefits beyond traditional physical therapy approaches. The technique appears particularly helpful for improving pain levels, movement quality, and stability. However, since participants received multiple therapies simultaneously, it's difficult to determine exactly how much the needle-based electrical stimulation contributed versus the other treatments. If you're interested in this approach, seek a qualified acupuncturist with training in electroacupuncture and experience treating musculoskeletal conditions.

This RCT (n=29, mean age 39.2±10.9 years) compared 6-week multimodal protocols for chronic low back pain, with the experimental group receiving intramuscular electrical stimulation (IMES) via acupuncture needles under ultrasound guidance targeting the multifidus, versus controls receiving TENS. Both groups received concurrent myofascial trigger point therapy and exercise. The IMES group demonstrated statistically significant improvements in muscle tension (right), tissue perfusion (bilateral), pressure pain threshold (left), NRS pain scores, ROM, and postural stability both immediately post-treatment and at 4-week follow-up (P<0.001 to 0.006). Muscle stiffness and maximal voluntary contraction showed no significant changes in either group. Clinical takeaway: IMES applied to multifidus via needle electrode appears superior to surface TENS for improving neuromuscular function, perfusion, and pain outcomes in chronic low back pain when integrated into multimodal care, though the multimodal design limits attribution of specific effects to the needle-based electrical stimulation intervention alone.