By Rhonda Mostyn BSc DC Cert LT
By Rhonda Mostyn BSc DC Cert LT
Rehabilitation of soft tissue injuries involves integrating the best
possible therapeutic tools at the optimal phases of healing.
Rehabilitation of soft tissue injuries involves integrating the best possible therapeutic tools at the optimal phases of healing. It’s kind of like baking. Use the finest chocolate in your cake, mix all the ingredients properly and you’ll turn out a quality dessert. For the patient, the dessert is simply feeling and functioning better in the fastest time possible. With new therapeutic products promoted on a regular basis, practitioners must make informed decisions when choosing the most effective tools for their patient programs. Technological advances in health-care products have made coming to these decisions even more challenging as the practitioner is obligated to stay up to date with new technology. As well, patients are more likely to “shop around” for the best choices in therapy.
|Lateral epicondylitis cold laser treatment.
For rehabilitation practitioners, as well as patients, cold laser therapy, an emerging technology, has become a frequent therapeutic choice. In this article we’ll look at why cold lasers have gained popularity in the area of injury rehabilitation.
EFFECTS ON HEALING: INFLAMMATION
Healing of soft tissue injuries can be generalized into three key phases: (1) initial inflammatory phase, (2) tissue repair stage, and (3) remodelling phase.1 The goal of integrating laser into the patient’s rehabilitation program will be to hasten or re-activate the healing process by stimulating each of these phases of healing.
The initial inflammatory phase, characterized by pain, swelling, redness and warmth, is an important stage of healing. Monocytes and macrophages aid in clearing necrotic material and angiogenesis takes place. In the case of rehabilitation of chronic injuries, inflammation has often been prolonged and is interfering with the progress to subsequent phases of healing.
Initiating cold laser therapy in the early stages of healing reduces the incidence of chronic inflammatory conditions. One of the most important functions of cold laser therapy is that it stimulates the metabolism of cells in damaged tissue and leads to increased cellular byproducts, including ATP. This increase in ATP can then be used to fuel an array of reparative processes required for healing in the tissues. The formation of new blood vessels, lymphatic vessels and collagen fibres is stimulated. Laser therapy also produces temporary vasodilation of blood vessels and activation of lymphatic vessels. The increased blood flow in the area helps to clear away inflammatory products while the enhanced lymphatic drainage removes the interstitial fluid that builds up in the inflamed site.
COLD LASERS AND TISSUE REPAIR
In addition to clearing away inflammation, cold laser therapy plays an important role in tissue repair. When damaged tissue is irradiated by laser, the number of fibroblasts in the tissue increases. Fibroblasts actively create new collagen by synthesizing the collagen precursor procollagen and modifying the procollagen into tropocollagen. The tropocollagen assembles into collagen fibrils, which then assemble into collagen fibres. New collagen fibres are then used to repair damaged tissue in the area, including ligaments, tendons and muscles.
Research has shown that chronic overuse injuries such as tendinosis are associated with a failed healing response in which the body’s fibroblasts produce abnormal tendon and ligament collagen.2,3 The normal parallel bundled fibre structure is disturbed; the continuity of the collagen is lost, with disorganized fibre structure and evidence of both collagen repair and collagen degeneration. Laser therapy, on the other hand, has been shown to promote new tissue fibres that are well organized and have up to 30 per cent greater tensile strength.
IMPROVED STRENGTH OF LIGAMENTS AND TENDONS
Fung et al. studied the morphology of collagen fibrils in healing medial collateral ligaments (MCL) in rats. The MCLs were surgically transected and were divided into three groups: those receiving laser treatment at a higher power (63.2 J/cm2), those receiving laser treatment at a reduced power (31.6 J/cm2), and a control group receiving no laser treatment. When the MCLs were examined at three and six weeks post surgery by electron microscopy, the researchers discovered that both laser-treated groups showed an increase in collagen fibril size.4
In a separate study, Oliveira et al. looked at the effect of laser therapy on healing of transacted Achilles tendons in rats. The researchers used polarization microscopy to examine and compare the collagen fibres in healing tendons of rats irradiated with laser compared with those in a control group. Their results supported an improvement in collagen fibre organization in the laser-treated group over the controls.5
WHERE DOES LASER FIT IN?
Laser therapy should be initiated from the first phase of rehabilitation to decrease inflammation and promote tissue healing. Decreased inflammation will aid in pain reduction and tissue healing will limit atrophy and fibrosis in tissues. In this author’s experience, the number of sessions required is largely dependent on the chronicity of the injury. Treatment initiated early in an acute injury may only require two to three weeks of care, whereas laser therapy initiated at a later phase, or for a chronic injury, will require about four to six weeks of treatment.
A COMMON PRESENTATION: LATERAL EPICONDYLITIS
There have been many studies reporting the efficacy of cold laser therapy treatment for lateral epicondylitis.6,7,8 Oken, et al. compared the effects of cold laser therapy to bracing or ultrasound in a prospective, randomized controlled trial. They divided 58 patients into three groups: bracing plus exercise, ultrasound plus exercise, and CLT plus exercise. Results from this study showed that bracing had a shorter beneficial effect than did ultrasound and laser therapy in reducing pain, and that laser was more effective than bracing and ultrasound in improving grip strength after treatment.9 In another study, Stergioulas compared treatment with a combination of laser and plyometric exercises to sham laser and plyometric exercises in 50 patients. Patients were treated for eight weeks, one to two times per week. The laser plus exercise group had a significant decrease in pain, increase in wrist range of motion and in grip strength and improved weight test results compared to the exercise only group at eight weeks of treatments and at eight weeks followup.10
Laser treatment for rehabilitation of this injury should be focused on repairing damage and minimizing fibrosis at the point of attachment of extensor carpi radialis brevis at the lateral elbow. Treatment can also be performed over the forearm extensor muscles to increase microcirculation and relax the muscles. Laser light is well absorbed by chromophore-rich blood, which is abundant in most tissues. However, relatively avascular structures such as tendons require relatively higher doses of laser light. A typical course of laser treatments for chronic lateral epicondylitis would require three to six weeks of treatments, scheduled a minimum of twice weekly.
CHOOSING A LASER FOR YOUR FACILITY
Once a rehabilitation practitioner has decided that a cold laser device will be an efficacious addition to their patient programs, they should spend time investigating and comparing laser systems. It’s important to choose a system that will best fit with their facility. For instance, if a large proportion of patients present with lower back pain or myofascial syndromes, a system with multiple lasers would be best to cover these large treatment areas. Short treatment times are very valuable in high-volume clinics in keeping pace with patient demand. Portability of the laser may be important in large facilities with several practitioners and treatment rooms. For any facility, a system that is easy to learn and operate is always best. The practitioner should also ensure that extensive training and support materials are included to minimize time out of their busy schedule for training new staff.
Although all cold lasers are not created equal, research supports this technology as an effective tool for healing musculoskeletal injuries. This research is valuable but it is not the key to the rising popularity of lasers in rehabilitation. Satisfied patients and practitioners drive this trend. An increase in high-quality laser products accommodates the needs of various facilities and thus supports this trend. In fact, the question is whether cold laser therapy is, in fact, a trend at all, as it establishes a solid reputation as treatment of choice in facilities nationwide.
- Tendon Injury and Tendinopathy: Healing and Repair, Sharma, P, Maffulli, N., The Journal of Bone and Joint Surgery (American). 2005; 87:187-202.
- Chronic Achilles tendinopathy. A survey of surgical and histopathological findings. Astrom M, Rausing A. Clin Orthop Jul; (316):151-64, 1995.
- Trauma modifies strength and composition of retrodiscal tissues of goat temporomandibular joint. Cooper B, Oberdorfer ML, Rumpf D, Malakhova OE, Rudman RA, Mariotti A. Oral Diseases 5:329-336, 1999.
- Effects of a Therapeutic Laser on the Ultrastructural Morphology of Repairing Medial Collateral Ligament in a Rat Model. Fung DT, Ng GY, Leung MC, Tay DK. Lasers Surg Med. 2003; 32(4):286-93.
- Effect of Low Level Laser Therapy With Different Therapy Regimes on The Process of Tissue Repair in Partial Lesion Calcaneous Tendon. Oliveira et al. Lasers Surg Med 2009 Apr; 41(4):271-6.
- A Systematic Review with Procedural Assessments and Meta-Analysis of Low Level Laser Therapy in Lateral Elbow Tendinopathy. Bjordal JM, Lopes-Martins RA, et al. BMC Musculoskeletal Disord. 2008 May 29; 9:75
- Effects of 904 nm Low Level Laser Therapy in the Management of Lateral Epicondylitis: a Randomized Controlled Trial. Lam LK, Cheing GL. Photomed Laser Surg. 2007 Apr; 25(2):65-71.
- Treatment of Medial and Lateral Epicondylitis with Low Level Laser Therapy: A Multicenter Double Blind, Placebo-Controlled Clinical Study on 324 Patients. Simunovic Z, Trobonjaca T, Trobonjaca Z. J Clin Laser Med Surg 1998 Jun; 16(3):145-51.
- The Short Term Effect of Laser, Brace, and Ultrasound Treatment in Lateral Epicondylitis: a Prospective, Randomized, Controlled Trial. Oken, O, Kahraman, Y, et al. J Hand Ther. 2008 Jan-Mar; 21:63-7.
- Effects of Low Level Laser and Plyometric Exercises in the Treatment of Lateral Epicondylitis. Stergioulas A, Photomed Laser Surg. 2007 Jun; 25(3):205-13.
Dr. Rhonda Mostyn, a chiropractor and certified laser technician, is the clinic director at Theralase, a leading Canadian manufacturer and distributor of cold lasers. As director, she oversees all aspects of patient laser treatment programs, clinical trials, training, and practitioner education. She has lectured extensively and published numerous articles on the topic of laser therapy. Prior to joining Theralase, Dr. Mostyn was the director of a multidisciplinary wellness clinic in Toronto from 1996-2006.