Scholarly paperPulsed Electromagnetic Fields for Treating Osteo-arthritis
Introduction
Osteo-arthritis, the most common form of arthritis, is usually accompanied by focal destruction of the articular cartilage lining of synovial joints, plus extensive subchondral bone remodelling and possible bone necrosis. It affects men and women equally, particularly in later life, and may involve one or more large peripheral joints and/or joints of the spine. The primary signs and symptoms of osteo-arthritis include pain and stiffness, weakness, joint instability, joint inflam-mation, joint deformity and a decreased range of joint motion. A general decrease in the ability to function physically occurs over time and may lead to impaired psychological function and social isol-ation, in addition to economic hardships.
Because there is no cure for osteo-arthritis, individuals with this disease, particularly those who have little benefit from prescribed medications or cannot use these drugs without hazard, are sent to physiotherapists for treatment to alleviate their symptoms and to restore optimal functional capacity.
Physical therapies commonly advocated for treating the symptoms of osteo-arthritis include exercise and a wide variety of electrotherapeutic modalities. Each shows some promise in improving one or more osteo-arthritic signs and symptoms even though adequate research in this field is sorely lacking.
In this respect, one electromagnetic modality constituted by low-frequency low-energy pulsed electromagnetic fields of single or pulse burst quasi-rectangular or triangular waveforms, which originated in its application to bone and wound healing, has been found to have prom-ising applications in this respect.
How effective pulsed electromagnetic fields are for treatment of joint pain, inflammation, bone damage and healing of articular cartilage and soft tissue lesions, which may all occur in people with osteo-arthritic joint disease, is the subject of this literature review. In particular we examine:
- ▪
Existing rationale underlying the application of pulsed electromagnetic fields for treatment of painful osteo-arthritic joints.
- ▪
Clinical effectiveness of therapeutic pulsed electromagnetic fields for treatment of osteo-arthritis and related conditions.
- ▪
Possible mechanisms to explain how exposure of articular tissue to pulsed electromagnetic fields may yield beneficial clinical results for people with osteo-arthritic joint disease.
Section snippets
Articular Cartilage
Under normal conditions, articular cartilage – the joint structure most affected by osteo-arthritis – is constituted by cells known as chondrocytes, which account for less than 10% of its volume. These cells manufacture, secrete and maintain the organic component of the extracellular compartment, or cart-ilage matrix, composed of a dense col-lagen fibril network enmeshed in a concentrated solution of proteoglycans and water. The importance of these structural interactions is that they determine
Results
The present search method revealed 15 relevant articles, but one was not clearly related to the application of electro-magnetic therapy (Zizic et al, 1995). Another used an animal model (Ciombor and Aaron, 2001), one was not published as a full-length study (Perrot et al, 1998) and one was a retrospective study (Hershler and Sjaus, 1999). The remainder related to the use of pulsed electromagnetic fields for bone healing or relief of pain and inflammation. Only two randomised controlled trials
Discussion
In general, most clinical reports reviewed in this paper indicate that positive results, over and above a strong placebo effect, can occur in terms of pain reduction and bone healing by the application of pulsed electromagnetic fields to damaged or painful tissues and osteo-arthritic joints, regardless of method of stimulation. This was also the recent conclusion of Quittan et al (2000) who examined all categories of usage of pulsed electromagnetic field therapy that have been documented in the
References (53)
- et al.
‘Pulsed electromagnetic fields therapy of persistent rotator cuff tendinitis: A double blind controlled assessment’
Lancet
(1984) - et al.
‘Stimulation of skeletal-derived cell cultures by different electric field intensities is cell-specific’
Biochimica and Biophysica Acta
(1985) - et al.
‘Effect of electromagnetic fields on bone mineral density and biochemical markers of bone turnover in osteoporosis: A single blind, randomised pilot study,’
Current Therapeutic Research–Clinical and Experimental
(2001) - et al.
‘Pulsed magnetic and electromagnetic fields in experimental Achilles tendonitis in the rat: A prospective randomised study’
Archives of Physical Medicine and Rehabilitation
(1997) - et al.
‘Pulsed electromagnetic fields influence hyaline cartilage extracellular composition without affecting molecular structure’
Osteo-arthritis and Cartilage
(1996) - et al.
‘Pulsed electromagnetic fields preserve proteoglycan composition of extracellular matrix in embryonic chick cartilage’
Biochimica and Biophysica Acta
(1997) - et al.
‘Hypothesis: Joints can heal’
Seminars in Arthritis and Rheumatism
(1984) ‘Electromagnetic fields and magnets. Investigational treatment for musculoskeletal disorders’
Rheumatic Disease Clinics of North America
(2000)- et al.
‘Response of pain to static magnetic fields in postpolio patients: A double-blind pilot study,’
Archives of Physical Medicine and Rehabilitation
(1997) - et al.
‘Early effects of electrical stimulation on osteogenesis’
Bone
(1996)