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

Objective: To evaluate the effects of individual and combination therapies (low-level laser therapy and physical exercises) on pain, stiffness, function, and spatiotemporal gait variables in subjects with bilateral knee osteoarthritis (OA).Methods: Subjects with knee OA (Grades 1-3) were evaluated and randomized into four groups: Control Group (CG), untreated; Laser Group (LG), treated with laser at 808 nm, 5.6 J; Exercise Group (EG), treated with exercise; and Laser + Exercise Group (LEG), treated with laser and exercises. The treatment was carried out twice a week for 2 months. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) questionnaire was applied for evaluation and reevaluation; evaluation of spatiotemporal gait variables was performed using GAITRite equipment.Results: The EG showed significant improvement in pain (p = 0.006) and function (p = 0.01) according to WOMAC. Regarding gait variables, in intergroup analysis after 8 weeks all groups receiving intervention showed a significant increase in gait speed: LG versus CG (p = 0.03); EG versus CG (p = 0.04) and LEG versus CG (p = 0.005). Only the group treated with laser + exercise showed a significant increase (p = 0.009) in the cadence and duration of single right limb support (p = 0.04), and only the groups treated with exercise and laser + exercise showed significant decreases in the duration of right limb support (p = 0.035 and p = 0.003, respectively), compared to the CG.Conclusions: The group treated only with exercise showed improvement in WOMAC questionnaire scores. Regarding the gait variables, all groups undergoing the interventions showed increases in the gait speed compared to the CG. The laser and exercise combination therapy provided the best results for the other gait variables (cadence and duration of right limb support and duration of single right limb support).Implications for rehabilitationThere are differences in gait patterns in patients with knee OA, including decreased gait speed, cadence, and step length.The results shown in the present study provide additional information about the physical therapy approaches that should be chosen during clinical practical to improve gait performance in individuals with knee osteoarthritis.The improvement in gait performance is a relevant issue due to the fact that is associated to physical independence and better quality of life.