Is low-level laser therapy effective in the management of lateral epicondylitis?

The purpose of “Evidence in Practice” is to illustrate how evidence is gathered and used to guide clinical decision making. This article is not a case report. The examination, evaluation, and intervention sections are purposely abbreviated. A 55-year-old woman, who was right-hand dominant, was referred to my physical therapy clinic with a 6-month history of pain in her left lateral elbow. The patient was an assembly-line worker in an automotive factory. She worked 40 to 50 hours per week in a rotating 9-job “loop” manufacturing diesel engines. Each day she would perform a different job in the loop for the duration of her shift, until she had performed all 9 job functions, at which point the “loop” would repeat. The initial examination revealed normal active range of motion of the left elbow and wrist (using techniques described by Norkin and White1), with pain when moving into active wrist extension. The patient's grip strength was assessed using a Jamar hydraulic hand dynamometer.* Compared with her right upper extremity, the patient had decreased grip strength in her left upper extremity of approximately 40 lb. Passive range of motion was painful when moving into wrist flexion. Tenderness to palpation was noted in the lateral epicondyle and in the proximal one third of the extensor tendons. Joint play testing of the humeroradial and humeroulnar joints, using techniques described by Kaltenborn and Evjenth,2 was within normal limits. Varus and valgus stress tests, cervical screening, and neurological screens did not reproduce symptoms at the elbow. The patient reported that her pain developed during one specific job in her loop—lifting oil pans out of a cardboard box and placing them on the line. She demonstrated how she lifted the oil pans from their packaging. The patient performed a 2-handed lift, using her wrist extensors to pull the oil pans up and toward herself. Each oil pan weighed between 4.1 kg and 7.2 kg (9 lb–16 lb), depending on the size of the engine being assembled. I immediately taught the patient proper lifting techniques using her biceps brachii muscles instead of her wrist extensors to lift and pull the oil pans, and she was advised to use this technique whenever lifting objects toward herself. The patient continued to work without restrictions at her job, and she was provided with a lateral counter-force brace to redistribute muscular forces away from her lateral epicondyle. The brace consisted of an inelastic cuff worn against the forearm extensors to diminish tension along the tendons proximal to the brace placement. I had recently been contacted by a vendor about purchasing a low-level laser as a new intervention for musculoskeletal disorders. The vendor discussed common diagnoses, such as lateral epicondylitis, seen in the workers' compensation setting and provided literature in support of low-level laser therapy (LLLT) with these diagnoses. Lateral epicondylitis is a very common diagnosis at my clinic; at any time, as many as 25% to 40% of the patients are being treated for this condition. The repetitive nature of lifting engine parts, the use of power tools, and the force required to twist parts onto engines leads to the referral of numerous patients with this condition for physical therapy each month. I reviewed the vendor’s literature in an attempt to gain a better understanding about types of lasers and their effectiveness with patients commonly seen in my clinic. The laser being promoted was a combination laser package that included: pulse laser (900±50 nm), infrared radiation (740 nm–860 nm), and visible red light (600 nm–740 nm). The clinician could choose between 5 programs that had been preset by the manufacturer. The programs varied in the treatment time (from 3 to 5 minutes) and pulse frequency (between 50 Hz/s and 3,000 Hz/s). The preset programs were titled: “Pain Syndrome, “Chronic Pain Syndrome,” “Skin & Wound Care,” “Anti-Aging & Cosmetics,” and “Specific Treatment Programs.” In addition, a sixth program could be personalized by the clinician providing treatment. The company provided a document supporting LLLT titled “Clinical Data.” Twenty-seven abstracts were included in this document. My cursory look at these abstracts revealed that 13 were papers that were not published in a journal, and 4 were repeated twice in the document. For these reasons, my selection of abstracts was limited to 10 articles (Fig. 1). Of the remaining articles, I did not review 8 articles: 3 articles were published more than 10 years previously (Yamaya et al, Ceccherelli et al, Beckerman et al) and therefore were not likely to reflect current practice, 2 studies reported on articular cartilage repair in animals (Akai et al, Calatrava et al), 2 abstracts described the use of lasers in treating nerve pain (Hashimoto et al, Eckerdal and Bastian), and another study described general responses to treatment with low-level lasers (Navratil and Dylevsky). The remaining 2 articles (Logdberg-Anderssont et al, Wong et al) seemed to be pertinent to patient populations commonly seen in my workers’ compensation clinic. Abstracts in the vendor’s “Clinical Data” handout. Abstracts in the vendor’s “Clinical Data” handout. In order to locate the remaining 2 abstracts provided by the vendor, I chose to access several databases through FirstSearch† (http://www.oclc.org), which is available for free at my academic institution where I am a DScPT student. I began my search through the MEDLINE database. At the main screen, I typed in laser therapy, and selected source phrase from the pulldown menu. “Source phrase” is a method of locating articles by phrases seen in the title of the journal. For example, typing the words physical therapy and selecting source phrase from the pulldown menu retrieves a list of 4,364 references, all from the journal Physical Therapy. I chose “laser therapy” as my source phrase, because the 2 articles I was trying to locate (Logdberg-Anderssont et al and Wong et al) were found in a journal titled Laser Therapy. My search produced no results. I believed that I was unable to retrieve these citations because Laser Therapy was not indexed in MEDLINE. To verify that this was the case, I went to the PubMed Web site (http://www.ncbi.nih.gov/PubMed) and clicked on Journals Database. In the next screen, I typed laser therapy in the query box. Two journals were retrieved, but neither was titled Laser Therapy. I next decided to try to locate this journal in the Cumulative Index to Nursing and Allied Health Literature (CINAHL) database, which includes journals not indexed through MEDLINE. Using “laser therapy” as my source phrase and CINAHL as my database, I once again attempted to retrieve citations for Logdberg-Anderssont et al and Wong et al. This search also produced no results. Although the vendor had provided literature in support of their product, I was not able to access the articles I had selected for critical analysis through 2 of the most common databases available to clinicians. Other databases that might contain citations to Laser Therapy, such as Allied and Complementary Medicine Database or Biological Abstracts, were not available through my institution’s FirstSearch subscription. I decided to conduct my own search of the literature to determine whether there was evidence, not provided by a vendor, to support the use of a low-level laser in the treatment of lateral epicondylitis. ■ Database used for search: MEDLINE I decided to access MEDLINE, because this database contains more than 11 million citations from more than 4,800 journals. I accessed MEDLINE through FirstSearch and performed the search on March 19, 2006. ■ Initial keywords: laser therapy and lateral elbow I started this search with 2 keywords: laser therapy and lateral elbow. I chose “laser therapy” because it was the primary intervention I was exploring. I chose the term “lateral elbow” because it reflected the location of the patient’s pain. I wanted the term to be broad enough to include a multitude of terms used to name this condition, including lateral epicondylitis, tennis elbow, and so on. ■ Limits: English language and the past 10 years I chose to limit my search to those studies written in English, and only articles published from 1996 to 2006. I felt that older studies might not reflect the most current practices regarding low-level laser as an intervention. With technology changing so rapidly, I wanted articles that reflected “state of the art” laser treatment. If my search did not produce enough studies, I could always go back and change my search parameters to include older articles. ■ Selection of articles for review: This search retrieved 9 citations (Fig. 2). I decided not to review 5 of the articles: 1 study (which was identified as a “pilot study”) included only 25 patients and had no control group (Stasinopoulos), 2 studies made only brief mention of laser as a new treatment modality (Sevier and Wilson, Green et al), 1 study discussed laser as an examination technique comparable to Doppler ultrasound (Ferrell et al), and the other study did not include an abstract and may have been a “Journal Club” article that was not a description of original research (Hoens). I deemed the remaining studies appropriate to include in my review because they described controlled trials (Simunovic et al, Basford et al) or systematic reviews (Trudel et al, Stasinopoulos and Johnson). Abstracts obtained from MEDLINE search. Abstracts obtained from MEDLINE search. Although systematic reviews are treated as higher levels of evidence,3 I chose to start my search with the controlled trials. Because I had no exposure to laser as an intervention, I wanted to gain a better understanding of treatment parameters, dosing levels, and so on when using LLLT. I thought the methods section of the controlled trials would contain this information, whereas such specific information might not be present in the systematic reviews. Simunovic Z, Trobonjaca T, Trobonjaca Z. Treatment of medial and lateral epicondylitis—tennis and golfer’s elbow—with low lever laser therapy: a multicenter, double blind, placebo-controlled clinical study on 324 patients. J Clin Laser Med Surg. 1998;16:145–151. This study included a brief introduction to laser therapy, providing an explanation of effects mediated by low-level laser. Three distinct lasers were used in the study, and 3 different treatment parameters were compared. The first laser was an infrared, gallium-aluminum-arsenide (GaAlAs), continuous-wave laser with a wavelength of 830 nm (0.830 µm). The output power was 120 mW, with a dosage of 10 J/cm2. The GaAlAs laser used direct skin contact, irradiating previously identified trigger points (TPs) specific to each patient. The second laser used in the study was a helium-neon (HeNe) continuous-wave laser. Its wavelength was 632.8 nm (0.632 µm), with output power of 10 mW. This laser has most often been used to treat wounds and mucous membranes.4 The HeNe laser was coupled with a second infrared laser, which had a wavelength of 904 nm (0.904 µm) and an output power of 30 mW. Together, these lasers were combined to create a scanning method of treatment. This second treatment involved irradiating the skin with a probe held 5 cm above the skin. The probe emitted beams containing light particles from both the HeNe laser and the infrared diode. The maximum dosage for this treatment was determined to be 12 J/cm2. The third and final treatment method involved a combination of direct skin contact and the scanning technique, using all of the aforementioned lasers. The study was conducted at 2 independent laser centers in Croatia and Switzerland. Subjects were required to have a definitive diagnosis of epicondylitis made by an orthopedist. The subjects ranged in age from 16 to 70 years old and represented a variety of occupational and socioeconomic groups (eg, athletes, butchers, drivers, hairdressers, painters, musicians, tailors, typists). The number of female and male subjects was not identified. The authors classified this study as a double-blind, placebo-controlled clinical study; however, a true control group did not exist. Subjects with unilateral symptoms were treated with either the scanning or combination methods. These subjects did not have a control group and were not treated with direct laser over TPs. Subjects with symptoms only direct laser to the and In all subjects with symptoms direct treatment to the most painful whereas the other only was noted in the more painful the were in laser on the painful and direct contact over the painful In to the of a control this study had several other A of 324 subjects in the study, 50 with medial epicondylitis and with lateral epicondylitis. the responses of the 2 to treatment were not compared. A second involved the of treatment Subjects with 5 during the first with 3 for subjects with In addition, the number of ranged from a of to a maximum of Although patients with were found to better than patients with it is whether the were because the patients with had more or because they more The of a true control group for patients with unilateral the to not use treatment for subjects with and the treatment and duration it to the effectiveness of the treatment For these reasons, the of this study did not evidence to either or the use of laser therapy in the treatment of lateral epicondylitis. Basford Laser therapy: a controlled of the effects of low laser on lateral epicondylitis. Med This study began with a brief literature review of the treatment parameters being used in laser to the visible red lasers have a wavelength of whereas infrared lasers are in the range of to Treatment from 1 to 4 for treatment to 10 to for musculoskeletal Laser are approximately The study was as a controlled with of subjects to treatment and control The and were to the of treatment A of subjects were for in the study; however, only were and the study in The subjects ranged in age from to 70 with of the being subjects had a diagnosis of lateral epicondylitis made by a in musculoskeletal The laser used in the study was a continuous-wave laser. The was approximately with a maximum dosage of J/cm2. This laser was most to the GaAlAs infrared used with direct skin contact in the study by Simunovic et al. the wavelength and dosage in the laser in the study by Basford et al, however, were Because the laser did not use visible neither the the could determine whether the was laser or a probe for treatment. Each was treated with of at points along the forearm and 3 points at and the lateral 1 point at the 1 point at the and 2 points along the medial epicondyle. The authors selected these points on a report. to the of the study, subjects in both groups did not in terms of treatment were no between the groups in terms of to or the from the treatment with In addition, there were no in to by grip and strength The authors made 2 points in their In the of the the authors that subjects who treatment were and had more pain than the control In a on the however, the authors that the treated group was than the control of the study included the use of a laser, identified by the authors as an for the treatment of musculoskeletal the are in the to In addition, because studies have not identified or parameters of this study could only the that this laser, at these parameters, was not in the treatment of lateral epicondylitis. these the study seemed The and were to the treatment Laser treatment was with with no in because my search had retrieved systematic which are one of the of evidence, I wanted to review those articles to my In addition, because several treatment parameters were described in the 2 studies I had I wanted to other studies for or in the treatment parameters for low-level laser. et al. for patients with lateral a systematic J The authors of this systematic review began with a search of MEDLINE, Database Database and the Database of terms included elbow, elbow, lateral epicondylitis, and a variety of treatment and so were limited to those written in the English those conducted on over the age of and studies using or term the authors did not The search retrieved independent the and abstracts of the study classified as by one articles were identified as Two independent each A was by either the 2 or a third independent who was in to the Each article was assessed using an on levels of studies did not the analysis by the independent only articles to be included in the systematic A of 9 studies that used laser therapy in the treatment of lateral epicondylitis were identified. The authors reported that studies found no between laser and 1 study found that pain or grip strength did not change with the of laser to physical therapy” term that was not by the and the other 2 studies and in grip and lifting when using LLLT. Although the authors of this systematic review reported laser therapy is in the treatment of lateral epicondylitis, they made an that many of the studies reviewed had In addition, treatment parameters and dosing for all treatment were often A in article by and identified several of the et al including no about the of the no of the term no about reviewed articles using a to the articles, and that were and regarding lateral epicondylitis and For these reasons, I decided to conduct an independent of the studies included in this Of the 9 studies to laser therapy in the treatment of lateral epicondylitis, were more than 10 years Of the remaining 2 articles, Basford et al first article in my search for the out of of all studies reviewed on This study determined that a laser was not in the treatment of lateral epicondylitis. The second article et was retrieved for This study a of than the Basford et al study, but the one third of the reviewed articles. The et al study used a GaAlAs laser with the nm power of 50 mW, and power of Subjects were into 2 a group that and an group that treatment by the GaAlAs laser. Treatment involved direct over the most on the elbow for Subjects were treated 3 for 2 the and the were to the of treatment being The authors found no between the 2 groups in both pain with a or a The authors did not how the was used as an The authors subjects to use the to their forearm muscles and to immediately when pain was The study did have several The control group began with pain to by the and there was a in the number of treatment in the article treatment whereas the of the and the only treatment In addition, the use of the as an was not identified. being a systematic the 9 studies included in the review were not described in enough to support or the effectiveness of laser the 2 studies in et al, et al) did not support the use of laser therapy in the treatment of lateral epicondylitis. Stasinopoulos of low-level laser therapy for lateral elbow Laser Surg. This article was as a systematic review that is on the use of LLLT in lateral epicondylitis. Although 2 authors are for the study, the methods section not whether the reviewed studies were by one or both the of the authors in this were not identified. The databases in the search were identified as MEDLINE, Index to and The search included a variety of terms used to lateral elbow pain epicondylitis, lateral tennis treatment laser, low power laser, low laser therapy, laser and study control The search was limited to studies in the English with subjects over the age of The authors selected only studies LLLT no or another or treatment controlled trials in which LLLT was as of another treatment (eg, in combination with were studies were selected on the only 9 studies were included in the systematic review the authors the of the articles. Each study was using a by et The each article on both the study and the of with a maximum of In this systematic one study a a study of low The remaining 8 studies had from 40 to by the A look at the 8 studies determined to have revealed that only 2 of them were written in the 10 years et al, Basford et The Basford et al study the using the This was with the in the et al The study by et al, however, a of only it the third study Because I had reviewed both of these studies I decided that no analysis was The authors of this systematic review reported for the effectiveness of LLLT in the treatment of lateral epicondylitis. they that to be conducted this intervention. The authors thought that their systematic review had many including a of because the of many of the articles had to be retrieved to information and the that a could not be conducted because the reviewed studies had different types of different types of and different clinical the patients Although the authors identified a to the of the articles they did not use the of this analysis to about the of the articles. This systematic my to include both the studies by Basford et al and et al in my In addition, this review that definitive treatment parameters have not been for with low-level laser. ■ on the available evidence, the studies by Basford et al and et al, I decided that LLLT would not be an intervention for my patient with lateral epicondylitis. Although one study (Simunovic et al) reported that laser therapy for patients with of lateral epicondylitis, the methods of this study had many the systematic reviews were not both reviews identified the Basford et al article as one of the methods and analysis sections of all the studies These to have in my decision on the of the study by Basford et al. I discussed the of my with my and I began a of physical therapy and of the proximal In addition, the patient was advised to her grip during and to her wrist and elbow as often as until her symptoms began to I to the vendor regarding the of my literature I in to providing abstracts in their articles or to such articles be provided to to for independent critical The research from who are independent of the the and include studies published in journals. My own literature search identified in current studies using low-level laser in the treatment of lateral epicondylitis. Although direct to was the most used regarding laser location of and most method of treatment direct contact, and so to be of LLLT be