Introduction: Osteoarthritis is the most common disease of the joints contributing to the failure of movement. The disease mostly affects the older part of the population, and is associated with suffering and reduced quality of life. Knee osteoarthritis contributes to joint dysfunction of varying severity. These are common causes of chronic ailments limiting physical activity, which may even complicate the performance of activities of daily living. Low-level laser therapy is thought to have an analgesic effect, as well as a biomodulatory effect on the microcirculation. The aim of this study was to evaluate the effectiveness of low- -level laser therapy on pain relief and functional improvement in patients with osteoarthritis of the knee. The effects of laser therapy alone and in combination with exercise were compared.
Materials and methods: 40 patients of mean age 65 years with knee osteoarthritis of both sexes were divided into two groups. Laser alone was used in group I (n = 20) and laser combined with kinesistherapy was used in group II (n = 20). All patients received the same dose of laser radiation, which was 3.0 J/cm², 10 Hz, 400 mW. In both groups a series of 10 treatments was performed daily. VAS, ranges of motion in the knee joint, and the strength of the quadriceps and biceps femoris muscles were used as the criteria of pain assessment in both groups. All measurements were taken before and after treatment.
Results: Significant pain reduction: I (p = 0.00009, R = 0.68); II (p = 0.00002, R = 0.86), increased range of flexion in the knee: I (p = 0.000001, R = 0.90); II (p = 0.00002, R = 0.85), increased range of extension in the knee: I (p = 0.042, R = 0.87); II (p = 0.0004, R = 0.9) and increased strength of the quadriceps femoris muscle: I (p = 0.03, R = 0.77); II (p = 0.0002, R = 0.9) and the biceps femoris muscle: I (p = 0.04, R = 0.80); II (p = 0.0007, R = 0.91) were found in both groups after treatment. With the exception of flexion of the knee (p = 0.027; r = 0.17), there were no statistically significant differences in other analysed parameters between the use of laser alone and laser therapy combined with exercise.
Conclusion: The use of laser in knee osteoarthritis reduces pain and improves the functional status of the patient. Laser therapy combined with kinesistherapy produces better therapeutic effects, and effectively improves the functional status of knee osteoarthritis. Exercise therapy applied in a series of 10 treatments is too short to significantly improve the functional status of the patient.