Effects of low-level and high-intensity laser therapy as adjunctive to rehabilitation exercise on pain, stiffness and function in knee osteoarthritis: a systematic review and meta-analysis



      When treating knee osteoarthritis (KOA), rehabilitation exercise is often combined with low-level (LLLT) or high-intensity laser therapy (HILT). However, the effectiveness of these combinations is still uncertain.


      To examine the effects of LLLT or HILT combined with rehabilitation exercise (LLLT + E or HILT + E) on pain, stiffness and function in KOA.

      Data sources

      Five databases (PubMed, Web of Science, CINAHL, PEDro and SPORTDiscus) were searched for relevant studies published up to 31 December 2019.

      Study selection

      KOA randomised controlled trials, LLLT + E or HILT + E against exercise alone with or without placebo laser, reported clinical outcomes, human studies and English language.

      Data synthesis

      Methodological quality was assessed by the PEDro and Cochrane risk-of-bias scales, and the meta-analysis was undertaken using RevMan 5.3.


      Of the 10 retrieved studies, six investigated LLLT + E, three on HILT + E, and one evaluated both. All the studies had high PEDro scores. However, as most of the studies employed a single type of laser therapy, only indirect comparison of LLLT + E and HILT + E was possible. This study found all treatment modalities were effective in reducing KOA symptoms. Interestingly, relative to control, the meta-analysis showed significant improvements in knee pain, stiffness and function for the HILT + E.


      Both LLLT and HILT are beneficial as adjuncts to rehabilitation exercise in the management of KOA. Based on an indirect comparison, the HILT + E seems to have higher efficacy in reducing knee pain and stiffness, and in increasing function. To confirm this finding, a direct comparative investigation of the two types of laser therapy may be necessary.
      Systematic review registration PROSPERO ID CRD42020206228


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        • Hawker G.A.
        Osteoarthritis is a serious disease.
        Clin Exp Rheumatol. 2019; 37: 3-6
        • Chen D.
        • Shen J.
        • Zhao W.
        • Wang T.
        • Han L.
        • Hamilton J.L.
        • et al.
        Osteoarthritis: toward a comprehensive understanding of pathological mechanism.
        Bone Res. 2017; 5: 16044
        • Clynes M.A.
        • Jameson K.A.
        • Edwards M.H.
        • Cooper C.
        • Dennison E.M.
        Impact of osteoarthritis on activities of daily living: does joint site matter?.
        Aging Clin Exp Res. 2019; 31: 1049-1056
        • Singh D.K.A.
        • Kamsan S.S.
        • Ahmad M.A.
        • Chien-Ying A.N.
        • Chua W.Q.
        • Padzil F.M.
        • et al.
        Knee associated problems and functional mobility among adults with knee osteoarthritis.
        Malays Health Sci. 2018; 16: 229-235
        • Puett D.W.
        • Griffin M.R.
        Published trials of nonmedicinal and noninvasive therapies for hip and knee osteoarthritis.
        Ann Intern Med. 1994; 121: 133-140
        • Osiri M.
        • Welch V.
        • Brosseau L.
        • Shea B.
        • McGowan J.
        • Tugwell P.
        • et al.
        Transcutaneous electrical nerve stimulation for knee osteoarthritis.
        Cochrane Database Syst Rev. 2000; 4CD002823
        • Welch V.
        • Brosseau L.
        • Peterson J.
        • Shea B.
        • Tugwell P.
        • Wells G.
        Therapeutic ultrasound for osteoarthritis of the knee.
        Cochrane Database Syst Rev. 2001; 3CD003132
        • Gur A.
        • Cosut A.
        • Sarac A.J.
        • Cevik R.
        • Nas K.
        • Uyar A.
        Efficacy of different therapy regimes of low-power laser in painful osteoarthritis of the knee: a double-blind and randomized-controlled trial.
        Lasers Surg Med. 2003; 33: 330-338
        • Alayat M.S.
        • Aly T.H.
        • Elsayed A.E.
        • Fadil A.S.
        Efficacy of pulsed Nd:YAG laser in the treatment of patients with knee osteoarthritis: a randomized controlled trial.
        Lasers Med Sci. 2017; 32: 503-511
        • Al-Rashoud A.S.
        • Abboud R.J.
        • Wang W.
        • Wigderowitz C.
        Efficacy of low-level laser therapy applied at acupuncture points in knee osteoarthritis: a randomised double-blind comparative trial.
        Physiotherapy. 2014; 100: 242-248
        • Alfredo P.P.
        • Bjordal J.M.
        • Dreyer S.H.
        • Meneses S.R.
        • Zaguetti G.
        • Ovanessian V.
        • et al.
        Efficacy of low level laser therapy associated with exercises in knee osteoarthritis: a randomized double-blind study.
        Clin Rehabil. 2012; 26: 523-533
        • RDMB Braghin
        • Libardi E.C.
        • Junqueira C.
        • Rodrigues N.C.
        • Nogueira-Barbosa M.H.
        • Renno A.C.M.
        • et al.
        The effect of low-level laser therapy and physical exercise on pain, stiffness, function, and spatiotemporal gait variables in subjects with bilateral knee osteoarthritis: a blind randomized clinical trial.
        Disabil Rehabil. 2019; 41: 3165-3172
        • Gomes C.A.F.P.
        • Leal-Junior E.C.P.
        • Dibai-Filho A.V.
        • de-Oliveira A.R.
        • Bley A.S.
        • Biasotto-Gonzalez D.A.
        • et al.
        Incorporation of photobiomodulation therapy into a therapeutic exercise program for knee osteoarthritis: a placebo-controlled, randomized, clinical trial.
        Lasers Surg Med. 2018; 50: 819-828
        • Kheshie A.R.
        • Alayat M.S.
        • Ali M.M.
        High-intensity versus low-level laser therapy in the treatment of patients with knee osteoarthritis: a randomized controlled trial.
        Lasers Med Sci. 2014; 29: 1371-1376
        • Yurtkuran M.
        • Alp A.
        • Konur S.
        • Ozcakir S.
        • Bingol U.
        Laser acupuncture in knee osteoarthritis: a double-blind, randomized controlled study.
        Photomed Laser Surg. 2007; 25: 14-20
        • Koutenaei F.R.
        • Mosallanezhad Z.
        • Naghikhani M.
        • Ezati K.
        • Biglarian A.
        • Nouroozi M.
        • et al.
        The effect of low level laser therapy on pain and range of motion of patients with knee osteoarthritis.
        Phys Treatments. 2017; 7: 13-18
        • Nazari A.
        • Moezy A.
        • Nejati P.
        • Mazaherinezhad A.
        Efficacy of high-intensity laser therapy in comparison with conventional physiotherapy and exercise therapy on pain and function of patients with knee osteoarthritis: a randomized controlled trial with 12-week follow up.
        Lasers Med Sci. 2019; 34: 505-516
        • Ciplak E.D.
        • Akturk S.
        • Buyukavci R.
        • Ersoy Y.
        Effciency of high intensity laser therapy in patients with knee osteoarthritis.
        Med Sci. 2018; 7: 4
        • Jang H.
        • Lee H.
        Meta-analysis of pain relief effects by laser irradiation on joint areas.
        Photomed Laser Surg. 2012; 30: 405-417
        • Rayegani S.M.
        • Raeissadat S.A.
        • Heidari S.
        • Moradi-Joo M.
        Safety and effectiveness of low-level laser therapy in patients with knee osteoarthritis: a systematic review and meta-analysis.
        J Lasers Med Sci. 2017; 8: 12-19
        • Farivar S.
        • Malekshahabi T.
        • Shiari R.
        Biological effects of low level laser therapy.
        J Lasers Med Sci. 2014; 5: 58-62
        • Kulchitskaya D.B.
        • Konchugova T.V.
        • Fedorova N.E.
        Comparative evaluation of the effects of high-intensity and low-intensity laser radiation on microcirculation among patients with knee arthritis.
        J Phys Conf Ser. 2017; 826012015
        • Makolinets K.V.
        • Makolinets K.V.I.
        • Morozenko D.V.
        • Gliebova K.V.
        • Danylchenko S.I.
        Dynamics of biochemical markers of connective tissue metabolism in patients with knee osteoarthritis during conservative treatment with laser therapy.
        Wiad Lek. 2019; 72: 802-806
        • Paolillo F.R.
        • Paolillo A.R.
        • Joao J.P.
        • Frasca D.
        • Duchene M.
        • Joao H.A.
        • et al.
        Ultrasound plus low-level laser therapy for knee osteoarthritis rehabilitation: a randomized, placebo-controlled trial.
        Rheumatol Int. 2018; 38: 785-793
        • Ordahan B.
        • Karahan A.Y.
        • Kaydok E.
        The effect of high-intensity versus low-level laser therapy in the management of plantar fasciitis: a randomized clinical trial.
        Lasers Med Sci. 2018; 33: 1363-1369
        • White P.F.
        • Elvir-Lazo O.L.
        • Yumul R.
        Cold laser therapy for acute and chronic pain management: a comparison of low-level and high-intensity laser therapy devices.
        Anesthesiol News. 2019; 13: 65-77
        • BTL-Corporate
        High Intensity Laser: Painless and non-surgical management.
        2020 (Available at: [Accessed 15 February 2020])
        • Kushibiki T.
        • Ishihara M.
        Biological function of low reactive level laser therapy.
        in: Tanaka Y. Photomedicine—advances in clinical practice. IntechOpen, London2017: 198-213
        • Hamblin M.R.
        Photobiomodulation or low-level laser therapy.
        Biophotonics. 2016; 9: 1122-1124
        • Wyszynska J.
        • Bal-Bochenska M.
        Efficacy of high-intensity laser therapy in treating knee osteoarthritis: a first systematic review.
        Photomed Laser Surg. 2018; 36: 343-353
        • Collins N.J.
        • Hart H.F.
        • Mills K.A.G.
        Osteoarthritis year in review 2018: rehabilitation and outcomes.
        Osteoarthr Cartilage. 2019; 27: 378-391
        • McAlindon T.E.
        • Bannuru R.R.
        • Sullivan M.C.
        • Arden N.K.
        • Berenbaum F.
        • Bierma-Zeinstra S.M.
        • et al.
        OARSI guidelines for the non-surgical management of knee osteoarthritis.
        Osteoarthr Cartilage. 2014; 22: 363-388
        • Huang Z.
        • Chen J.
        • Ma J.
        • Shen B.
        • Pei F.
        • Kraus V.B.
        Effectiveness of low-level laser therapy in patients with knee osteoarthritis: a systematic review and meta-analysis.
        Osteoarthr Cartilage. 2015; 23: 1437-1444
        • Stausholm M.B.
        • Bjordal J.M.
        • Lopes-Martins R.A.B.
        • Joensen J.
        Methodological flaws in meta-analysis of low-level laser therapy in knee osteoarthritis: a letter to the editor.
        Osteoarthr Cartilage. 2017; 25: 9-10
        • Stausholm M.B.
        • Naterstad I.F.
        • Joensen J.
        • Lopes-Martins R.A.B.
        • Sebo H.
        • Lund H.
        • et al.
        Efficacy of low-level laser therapy on pain and disability in knee osteoarthritis: systematic review and meta-analysis of randomised placebo-controlled trials.
        BMJ Open. 2019; 9031142
        • Bannuru R.R.
        • Osani M.C.
        • Vaysbrot E.E.
        • Arden N.K.
        • Bennell K.
        • Bierma-Zeinstra S.M.A.
        • et al.
        OARSI guidelines for the non-surgical management of knee, hip, and polyarticular osteoarthritis.
        Osteoarthr Cartilage. 2019; 27: 1578-1589
        • Hou Y.
        • Yang Z.
        • Lin J.
        • Chen Y.
        • Xing D.
        • Wang B.
        Systematic review of clinical practice guidelines on exercise therapy for knee osteoarthritis and critical appraisal using AGREEII instrument.
        Osteoarthr Cartilage. 2018; 26: 324-325
        • Morton N.A.D.
        The PEDro scale is a valid measure of the methodological quality of clinical trials: a demographic study.
        Aust J Physiother. 2009; 55: 129-133
        • Bjordal J.
        Low level laser therapy and world association for laser therapy (WALT) dosage recommendations.
        Photomed Laser Surg. 2012; 30: 61-62
        • Hawker G.A.
        • Mian S.
        • Kendzerska T.
        • French M.
        Measures of adult pain: Visual Analog Scale for Pain (VAS Pain), Numeric Rating Scale for Pain (NRS Pain), McGill Pain Questionnaire (MPQ), Short-Form McGill Pain Questionnaire (SF-MPQ), Chronic Pain Grade Scale (CPGS), Short Form-36 Bodily Pain Scale (SF-36 BPS), and Measure of Intermittent and Constant Osteoarthritis Pain (ICOAP).
        Arthritis Care Res (Hoboken). 2011; 63: 240-252
        • Choi H.W.
        • Lee J.
        • Lee S.
        • Choi J.
        • Lee K.
        • Kim B.K.
        • et al.
        Effects of high intensity laser therapy on pain and function of patients with chronic back pain.
        Phys Ther Sci. 2017; 29: 1079-1081
        • Alfredo P.P.
        • Bjordal J.M.
        • Junior W.S.
        • Lopes-Martins R.A.B.
        • Stausholm M.B.
        • Casarotto R.A.
        • et al.
        Long-term results of a randomized, controlled, double-blind study of low-level laser therapy before exercises in knee osteoarthritis: laser and exercises in knee osteoarthritis.
        Clin Rehabil. 2018; 32: 173-178
        • Chen H.
        • Zheng X.
        • Huang H.
        • Liu C.
        • Wan Q.
        • Shang S.
        The effects of a home-based exercise intervention on elderly patients with knee osteoarthritis: a quasi-experimental study.
        BMC Musculoskelet Disord. 2019; 20: 160
        • Lee J.A.
        • Choi M.
        Effective behavioral intervention strategies using mobile health applications for chronic disease management: a systematic review.
        BMC Med Inform Decis. 2018; 18: 12
        • Sittig S.
        • Wang J.
        Incorporating behavioral trigger messages into a mobile health app for chronic disease management: randomized clinical feasibility trial in diabetes.
        JMIR mHealth uHealth. 2020; 8e15927
        • Anwer S.
        • Alghadir A.
        Pain management in knee osteoarthritis.
        in: Prostran M. Pain management. InTechOpen, London2016: 10
        • Page P.
        Current concepts in muscle stretching for exercise and rehabilitation.
        Int J Sports Phys Ther. 2012; 7: 109-119
        • Glass N.A.
        • Torner J.C.
        • Frey Law L.A.
        • Wang K.
        • Yang T.
        • Nevitt M.C.
        • et al.
        The relationship between quadriceps muscle weakness and worsening of knee pain in the MOST cohort: a 5-year longitudinal study.
        Osteoarthr Cartilage. 2013; 21: 1154-1159
        • Shiozawa H.
        • Ohsawa T.
        • Tsushima Y.
        • Higuchi T.
        • Takagishi K.
        • Chikuda H.
        Evaluation of muscle activity just after straight leg raising exercise by using 18FDG-PET.
        Orthop Sci. 2018; 23: 328-333
        • Probst P.
        • Grummich K.
        • Heger P.
        • Zaschke S.
        • Knebel P.
        • Ulrich A.
        • et al.
        Blinding in randomized controlled trials in general and abdominal surgery: protocol for a systematic review and empirical study.
        Syst Rev. 2016; 5: 48