In a never ending effort to find ways to help patients with low back pain, many different treatment approaches have been tried. In this report, researchers from Spain take a look at the effectiveness of shock wave therapy (also known as vibrotherapy) and ultrasound in the treatment of both acute and chronic back pain.
Both of these tools provide mechanical vibration to the spine in an effort to increase blood circulation, improve soft tissue stretch, reduce pain and stiffness, and speed up healing. Other potential effects of shock wave and ultrasound therapy may include enhanced cellular metabolism, muscle relaxation, and increased trunk/spinal motion.
They conducted the study as a systematic review. This means they searched all the currently published literature looking for studies on either of these two treatment methods. They found a total of 13 studies but only four randomly controlled trials.
The reported results then are based on the experiences of 252 patients. Various treatment methods were used and compared with ultrasound such as lumbar traction, low power laser, electrical stimulation, and spinal manipulation.
It was a bit difficult making clear comparisons since every study had its own duration (e.g., treatment three times a week for three weeks; treatment daily, five times a week for three weeks; treatment once or twice a week for a total of four sessions, etc). And results or final outcomes were measured using different tools (pain assessment, function, disability, walking distance, spinal motion, emotional functioning and coping).
The one constant in all the studies was that ultrasound was compared to a sham procedure. Sham treatments are a placebo created by using the machine (e.g., laser, electrical stem) but without actually turning it on. Here's a summary of the results:
- Patients with new (acute) back and leg pain had similar results with ultrasound, traction, and laser (see the next comment).
- None of these three treatments were effective for low back pain (with or without leg pain).
- It is possible that the "similar" results were nothing more than patients getting better through the natural healing process.
- Patients with chronic back pain (no leg pain) responded best to spinal manipulation.
Shock wave and electrical therapy had about the same (minimal) results.
- None of the studies looked at cost-effectiveness so there's no word on that.
Also none of the studies mentioned adverse effects for any of the treatments. There may have been some problems or complications but we don't know that on the basis of this review.
This is an important study because ultrasound especially is still a common modality used in the treatment of back pain. Primary care physicians and chiropractors recommend its use. Physical Therapists around the world still use it despite all the evidence (including the results of this study) that show it is not effective.
The authors of this systematic review repeat what has said before. Not only should shock wave therapy and ultrasound NOT be used to treat low back pain (acute, chronic, with or without leg pain) but studies using these modalities should not continue to be funded. With over 200 different treatments currently available, it would make more sense to find successful treatments that are also cost-effective. Future studies should be focused in this direction rather than re-studying something that has been disproven so thoroughly.
Reference: Jesús Seco, MD, PhD, et al. The Efficacy, Safety, Effectiveness, and Cost Effectiveness of Ultrasound and Shock Wave Therapies for Low Back Pain: A Systematic Review. In The Spine Journal. October 2011. Vol. 11. No. 10. Pp. 966-977.