https://doi.org/10.1177/0269215517723162 Clinical Rehabilitation 1–6 © The Author(s) 2017 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0269215517723162 journals.sagepub.com/home/cre CLINICAL REHABILITATION 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 Patrícia Pereira Alfredo 1 , Jan Magnus Bjordal 2 , Washington Steagall Junior 3 , Rodrigo Álvaro Brandão Lopes Martins 4 , Martin B Stausholm 2 , Raquel Aparecida Casarotto 1 , Amélia Pasqual Marques 1 and Jon Joensen 2 Abstract Objectives: To assess the long-term effects of low-level laser therapy (LLLT), in combination with strengthening exercises in patients with osteoarthritis of the knee. Design: Follow-up results at three and six months in a previously published randomized, double-blind, placebo-controlled trial. Setting: Specialist Rehabilitation Services. Subjects: Forty participants of both genders, aged 50–75 years with knee osteoarthritis grade 2–4 on Kellgren–Lawrence scale. Intervention: The LLLT group received 10 LLLT treatments with invisible infrared laser (904 nm, 3 Joules/point) over three weeks followed by an eight-week supervised strengthening exercise program. The placebo LLLT group received identical treatment, but the infrared laser output was disabled. 1 Department of Physical Therapy, Speech Therapy and Occupational Therapy, School of Medicine, University of São Paulo, São Paulo, Brazil 2 Physiotherapy Research Group, Department of Global Public Health and Primary Care, University of Bergen, Bergen, Norway 3 Department of Dentistry, School of Odontology, University of São Paulo, São Paulo, Brazil 4 Department of Pharmacology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil Corresponding authors: Patrícia Pereira Alfredo, Department of Speech Therapy, Physical Therapy and Occupational Therapy, School of Medicine, São Paulo University, São Paulo, Brazil; Rua Cipotânea, 51, Cidade Universitária, São Paulo 05360-160, Brazil. Email: patriciaalfredo@usp.br Amélia Pasqual Marques, Department of Speech Therapy, Physical Therapy and Occupational Therapy, School of Medicine, São Paulo University, São Paulo, Brazil, Rua Cipotânea, 51, Cidade Universitária, São Paulo 05360-160, Brazil. Email: pasqual@usp.br 723162CRE 0 0 10.1177/0269215517723162Clinical RehabilitationAlfredo et al. research-article 2017 Original Article