Efeito de diferentes potências de saída de um dispositivo de fototerapia na hiperalgesia de pacientes com tendinite de calcâneo

Abstract

The use of phototherapy has been proving to be favorable in the tendon repair process. Although several studies attest to the beneficial effect of phototherapy on tendinopathies, few study the effect of different potencies on hyperalgesia in patients with Achilles tendonitis. Therefore, this study aims to compare the effect of a single irradiation of four different powers on pain, functional capacity and inflammation in patients with Achilles tendonitis. For this purpose, a randomized, crossover, controlled and triple-blind clinical trial (therapist, patient and evaluators) was carried out, in which 7 male patients with Achilles tendinitis were recruited, randomly distributed according to the protocol order received, A, B, C or D. In all protocols, patients had the tendon in a relaxed condition, and phototherapy applications were performed with the patient lying down. Prior to the applications, the affected Achilles tendon (right or left) was marked at its midpoint and ultrasound images were acquired to measure the thickness of the tendon and the skin, tendon, and skin set. Functional capacity was assessed using the single hop test, pain was assessed using the Visual Analogue Scale (VAS) and also by algometry. Then, the patients received phototherapy with the application of the following protocols: A (657 J for 225 seconds), B (657 J for 135 seconds), C (657 J for 90 seconds) and D (18 J for 90 seconds). Application was by sweeping with continuous movement of the emitter along the tendon. The functional evaluations, through the single hop test, of pain through VAS and algometry, were performed previously, immediately, 30 minutes and 2 hours after the four phototherapy applications. Regarding pain assessment through VAS, protocol A showed a significant difference (p<0.05) when compared to protocol D, 2 hours after irradiation. The results obtained from algometry do not demonstrate statistically significant differences in the pain threshold between the tested protocols. In the assessment of tendon function using the Single Leg Hop Test, the data did not show statistical difference when comparing the different evaluation times and between the different protocols. Our results show that in a single application, protocol A with lower power and longer irradiation time proved to be effective in reducing pain in patients with Achilles tendonitis compared to the other protocols studied.