BENEFITS OF HIGH-POWER LASER THERAPY IN TREATING KNEE OA

By Mark Callanen, PT, DPT,OCS

This article is provided by ourTraveling Fellowship Co-TitlingSponsor, LightForce TherapyLasers.

Most clinicians are familiar withknee osteoarthritis (OA), butwhen pressed on its exact mecha-nisms regarding pain and inflammation, there can be someconfusion. Often, clinicians incorrectly jump to the “bone onbone” causal assumption regard-ing the source of pain for OA diagnoses. Prior to the advancedstages where this may be thecase, there are numerous tissuesin the knee that are innervatedand can become pain generatorsduring both the initial and latestages of OA. These include thejoint’s intra-articular and periarticular structures, includingmenisci, adipose tissue, synovium, and periosteum.1

While cartilage is a-neural, as thecartilage’s extra cellular matrixbreaks down and collagen andproteoglycans are lost, this degra-dation can lead to inflammatoryresponses in the joint that canpromote pain.

Cartilage’s pathological processwill eventually enter fibrillation,where the articular cartilage sur-face begins to roughen andprogress towards fissuring, atwhich point cartilage begins tobreak off from the subchondralbone. This will expose areas ofthe periosteum which are highly

innervated. When pressure is applied on this tissue, pain en-sues. This is accompanied by ad-ditional pain and inflammationas the body tries to “clean up” thejoint space.

In the late phases of OA, fissuring leads to eburnation ofthe joint surface and is often accompanied by bone spur for-mation as the body tries to repairthe damaged boney surface. Atthis point, compression of thejoint surface often becomesacutely painful and more inva-sive treatments are introducedthat may include injections,arthroscopy, and potentially jointreplacement surgery.1

When managing knee OA, it isimportant to promote early inter-vention to slow and/ or avoid thelate stage sequalae. Often, thehealth care system fails to edu-cate individuals that OA is aprocess, not simply a diagnosisthat results in joint replacementsurgery. This can lead to patientsfeeling unempowered when itcomes to managing their condi-tion. Psychological counseling isrecommended in chronic OAcases to help address depressionand other related considerations.2

It has been shown that whenjoint inflammation and pain areaddressed early, it can have a sig-nificant impact on the health and

longevity of the joint. This canhave dramatic implications onjoint mechanics, ROM, strengtharound the joint, and ultimatelyimproved weight bearing andfunctional status. When ineffec-tively managed, knee OA can significantly impact quality of lifeand is associated with increasedmorbidity and mortality risk.3

This is significant given that kneeOA impacts over 27 millionAmericans annually.1

Early treatment for knee OA centers around decreasing painand improving function. Whilephysical therapy that consists ofstretching and strengthening exercises has been shown to sig-nificantly benefit this patientpopulation,4,5 the initial focus ofmost plans of care center aroundreducing pain and inflammationat the knee. This is accomplishedvia oral medications that includesteroidal and non-steroidalanti-inflammatory medications(NSAIDS), opioid agonists (e.g.,Tramadol), acetaminophen(paracetamol), and interleukin-1inhibitors.1 If these are not suc-cessful, intra-articular injection ofcorticosteroids or hyaluronic acidmay be introduced to further im-prove pain and function.1

Given the unwanted side-effectsof many pharmaceuticals, clinicians should be aware ofmodalities that are supported inthe literature that help reducesynovial pain and inflammation.High-power laser therapy canhelp by eliciting photobiomodula-tion in areas where damaged tissue and inflammation reside.Due to the cost associated withClass 4 equipment, it is oftenoverlooked.

While there is mounting evidence to support these mecha-nisms and the benefits of usinglaser on arthritic pathology,6,7

endorsements from different pro-fessional groups have beenmixed. The European LeagueAgainst Rheumatism (EULAR)suggested in 2003 that low levellaser therapy (LLLT) in additionto other non-pharmacological approaches should be consideredwhen planning optimal treat-ment for osteoarthritis.3

Recommendations from othergroups have been less clear. The2013 knee OA recommendationsfrom the American Associationof Orthopedic Surgeons (AAOS)were neither for nor againstmodalities (including electrother-apeutic modalities), based onconflicting research. However;no mention of low-level lasertherapy (LLLT) was made in theirreview. As an aside, they foundmanual therapy results to be inconclusive as well, while theyfound strong evidence againstthe use of acupuncture for treat-ing knee OA.5

The Journal of Orthopedic andSports Physical Therapy (JOSPT)recently updated their guidelineson Knee Pain and Mobility Impair-ments: Meniscal and Articular Car-tilage Lesions Revision 2018. Again,no mention of laser was in theupdate, but they did support useof “biofeedback and muscle stim-ulation to patients followingmeniscus procedures to increasequadriceps strength, functionalperformance, and knee func-tion.”4 It should be noted thatJOSPT has supported use of LLLTin its 2017 Clinical Guidelines forTreating Cervical Dysfunction and

2014 Clinical Practice Guidelines forTreating Heel Pain/Plantar Fasciitis.

Why would laser be effective inhelping these patients? Whenlooking at the pain-generatingcomponents of early OA, it be-comes clear. The most commonsymptoms of OA are inflamma-tion and swelling of the synovia.7

High-power laser has the abilityto quickly reduce peripheral painvia its impact on peripheralnerves and the endocrine system, while providing lastingrelief due to its ability to reduceinflammation in arthritic jointsvia its impact on cytokines.3,6,7

High-power lasers’ impact on peripheral nerve tissue is notwell known by many clinicians.Its ability to reduce the conduc-tion velocity and compound action potentials (CAP) of sen-sory nerves (C and A delta painfibers), can reduce the pain signal produced from a periph-eral joint once threshold levels ofirradiance are reached during atreatment.8,9 This can lead toanalgesic effects lasting up to 24hours after a treatment.8

By reducing pain and inflamma-tion at the knee, patients canoften progress their weight bearing status and increase theiractivity levels, which can helpprevent a host of co-morbiditieswhich often exacerbate their con-dition: increased weight gain,Type 2 Diabetes, and central sen-sitization in the most severecases.1

Due to the prevalence of kneeOA, clinicians should consideradding laser to their arsenal inthe fight against this disease.

This non-invasive modality hasthe ability to address pain inunique ways that other treatmentoptions cannot. While it is not cur-rently the standard of care, ashigh-power laser continues to gainrecognition in the fight againstpain and inflammation, it has thepotential to become the modalityof choice when treating this chal-lenging patient population.

References:

1. International Association of Pain (IASP) 2010 Recommendations: Osteoarthritis Related Pain. https://s3.amazonaws.com/rdcms-iasp/files/production/public/Content/ContentFolders/GlobalYearAgainstPain2/MusculoskeletalPainFactSheets/Osteoarthritis_Final.pdf

2. Keefe FJ, Caldwell DS, Williams DA, et al. Pain copingskills training in the management of osteoarthritic knee pain: II. Follow-up results. Behav Ther. 1990;21:435-447.

3. Jordan KM, Arden NK, Bannwarth B, et al. EULAR Recommendations 2003: an evidence-based approach to the management of knee osteoarthritis: report of a task force of the standing committee for international clinical studies including therapeutic trials (ESCISIT). Ann Rheum Dis. 2003;62: 1145–1155.

4. Logerstedt D, Scalzitti DA,Bennell KL, et al. Knee pain and mobility impairments: meniscal and articular cartilage lesions revision 2018. Clinical practice guidelines linked to the international classification of functioning, disability and health. J Ortho Sports Phys Ther. 2018; Volume 48 Issue 2:A1–A50.

5. American Academy of Orthopedic Surgeons. Treatment of osteoarthritis of the knee. Evidence-basedguideline second edition. https://www.aaos.org/cc_files/aaosorg/research/guidelines/treatmento-fosteoarthritisofthekneeguide-line.pdf

6. Alfredo PP, Bjordal JM, Dreyer SH, et al. Efficacy of low level laser therapy associated with exercises in knee osteoarthritis: a randomized double-blind study. Clin Rehab. 2012:26523–26533.

7. Justyna Wyszynska J, Bal-Bochenska M. Efficacy of high-intensity laser therapy intreating knee osteoarthritis: a first systematic review. Photomed Laser Surg. Vol. 36, No. 7. Published online: 1 Jul 2018. https://doi.org/10.1089/pho.2017.4425.

8. Chow et al. Inhibitory effects of laser irradiation on peripheral mammalian nerves and relevance to analgesic effects: a systematic review. Photomed Laser Surg. Volume X, Number X. 2011; Mary Ann Liebert, Inc.:1-17.

9. Holanda VM, et al. The mechanistic basis for photo-biomodulation therapy of neuropathic pain by near infrared laser light. Laser Surg Med. 2017;49:516-524.

For questions or information aboutthis article, please contact BaileyBrickley at baileyb@litecure.com.