Physical Therapy Modalities
According to a recent study by Feine and Lund (1) of McGill University, there is little evidence that physical therapy and physical therapy modalities provide any long-term efficacy greater than placebo. The therapies which were examined included exercise, ultrasound, thermal agents, acupuncture, low-intensity laser therapy, electrical stimulation, and combination therapies for a variety of musculoskeletal pain conditions including chronic back pain. Patients receiving either therapy or placebo seemed to do better during either. It was concluded that giving a patient attention has a powerful effect, regardless of treatment.
The authors wrote, “We are not pleased to have to report that…our results suggest that none of the therapies under review cause improvements in symptoms of chronic musculoskeletal pain or in quality of life that outlast the therapy…including placebo.”
van den Hoogen et al (2) published the results of a study involving 269 patients. The objective of these investigators was to identify prognostic indicators of the duration of low back pain in general practice, and the occurrence of a relapse. It was concluded that receiving physical therapy was associated with a longer duration of low back pain. The authors reported, “at every moment in time, patients receiving physical therapy had a 51% less chance to recover in the following week than patients not receiving physical therapy.”
Clinical Guidelines for the Management of Acute Low Back Pain (3), produced by the Royal College of General Practitioners in Great Britain, address the appropriateness of physical agents and modalities. The Guidelines state that, “Although commonly used for symptomatic relief, these passive modalities do not appear to have any effect on clinical outcomes.” The modalities listed in the Guidelines include ice, heat, short wave diathermy, massage, and ultrasound. How about bed rest and traction? Bad news. “Traction does not appear to be effective for low back pain or radiculopathy…The evidence shows that bed rest with traction is ineffective. It adds the complications of immobilsation to the deleterious effects of bed rest.” Regarding manipulation under anesthesia: “There is no evidence that manipulation under general anesthesia is effective. It is associated with an increased risk of neurological damage.”
The AHCPR Guideline for Acute Low Back Problems in Adults (4) concurs: “The use of physical agents and modalities in the treatment of acute low back problems is of insufficiently proven benefit to justify their cost…Only two studies evaluated physical agents and modalities in patients with acute low back pain. Neither found significant differences in self-rated pain relief or other outcome measures between patient groups receiving physical agents and modalities (including diathermy, ultrasound, flexion/extension exercises, massage, and electrotherapy) and groups receiving a placebo.”
A study of 324 patients found no differences in outcomes in those receiving three different types of TENS and those given a sham TENS unit with indicator lights but no output (5).
Is ultrasound effective? Gam and Johannsen (6) reviewed 293 papers published since 1950 to assess the evidence of effect of ultrasound for musculoskeletal disorders. Serious methodological problems existed in many of the papers. However, in 13 cases data were presented in a way that made pooling possible. The conclusion: “None of the methods gave evidence that pain relief could be achieved by ultrasound treatment.”
Another meta-analysis looked at 400 randomized clinical trials. Meta-analyses were performed for disorders of the back, neck, shoulder and knee. Results indicated that “In general, the methodological quality of the studies appeared to be low, and the efficacy of physiotherapy was shown to be convincing for only a few indications and treatments (7).”
A controlled study was performed comparing osteopathic manipulation and short-wave diathermy in the treatment of non-specific low back pain (8). The placebo group, which received detuned diathermy, did about as well as those receiving real diathermy or osteopathy. The authors stated, “Benefits obtained with osteopathy and short-wave diathermy in this study may have been achieved through a placebo effect.”
In a study comparing drug therapy, conservative physiotherapy and manipulative physiotherapy, “Serial assessments of pain and spinal mobility showed similar response rates in all three treatment groups and no significant difference between therapies (9).”
Skargren et al (10) reported the results of a study involving 323 patients who were assigned to care by a physiotherapist or a chiropractor. A visual analog scale and the Oswestry pain disability questionnaire were used to evaluate the results. Those receiving chiropractic “treatment” received primarily “manipulation.” Those in the physiotherapy group received a variety of treatment modalities. The mean number of chiropractic visits was 7. The mean number of PT visits was 7.9. The conclusion: “Both chiropractic and physiotherapy as primary treatment reduced the symptoms. No difference in outcome as primary treatment reduced the symptoms. No difference in outcome or direct or indirect costs between the two groups could be seen, nor in subgroups defined as duration, history, or severity.” However, this study did not address the correction of vertebral subluxation.
We must differentiate manipulation for the treatment of musculoskeletal pain from adjustment for the correction of vertebral subluxation the unique service provided by doctors of chiropractic.
Skargren’s team found that chiropractic “manipulation” was as good as physiotherapy at symptom relief, and according to Feine and Lund, PT is as good as a placebo.
The framers of the Mercy document, chose to produce “consensus” guidelines rather than “evidence based” guidelines. As a consequence, physical therapy modalities received an “established” rating, the highest rating possible.
1. Feine JS, Lund JP: An assessment of the efficacy of physical therapy and physical modalities for the control of chronic musculoskeletal pain. Pain 1997;71:5.
2. van den Hoogen HJM, Koes BW, Deville W, et al: The prognosis of low back pain in general practice. Spine 1997;22(13):1515.
3. Clinical Guidelines for the Management of Acute Low Back Pain. Royal College of General Practitioners. September, 1996. Available at http://www.rcgp.org.uk
4. Clinical Practice Guideline Number 14. Acute Low Back Problems in Adults. Agency for Health Care Policy and Research. December 1994.
5. No better than placebo. Another look at TENS units for low back pain. Spine Letter 1997;4(5):2.
6. Gam AN, Johannsen F: Ultrasound therapy in musculoskeletal disorders: a meta-analysis. Pain 1995;63(1):85.
7. Beckerman H, Boulter LM, van der Heijden GJ, et al: Efficacy of physiotherapy for musculoskeletal disorders: what can we learn from the research? Br J Gen Pract 1993;43(367):73.
8. Gibson T, Grahame R, Harkness J, et al: Controlled comparison of short-wave diathermy treatment with osteopathic treatment in non-specific low back pain. Lancet 1985;1(8440):1258.
9. Waterworth RF, Hunter IA: An open study of diflunisal, conservative and manipulative therapy in the management of acute mechanical low back pain. N Z Med J 1985:98(779):372.
10. Skargren EI, Oberg BE, Carlsson PG, Gade M: Cost and effectiveness analysis of chiropractic and physiotherapy treatment for low back and neck pain. Spine 1997;22:2167.