Fotobiomodulação em mulheres com dor miofascial do assoalho pélvico: um estudo de viabilidade

Abstract

Introduction: Pelvic myofascial pain is identified in the pelvic floor muscles and internal hip muscles and is associated with significant impact on physical, functional, and psychosocial domains. Among the treatment methods for this pelvic dysfunction, photobiomodulation therapy stands out. Objective: To evaluate the feasibility of a randomized controlled clinical trial investigating the safety and efficacy of photobiomodulation, comparing three different parameters of low-intensity laser therapy for pelvic floor myofascial pain in women. Methods: This is a feasibility study for a randomized clinical trial with a blinded evaluator and concealed allocation, conducted from January to November 2024 at the Pelvic Physical Therapy Clinic of the Maternidade Escola Assis Chateaubriand, Fortaleza - CE, Brazil. The sample size was 21 participants (alpha 0.05, power 80%), with seven women in each group, who were assessed before and after the intervention. Primary outcomes: pain, recruitment, treatment adherence, retention, safety, and adverse events. Secondary outcomes: pelvic floor muscle function and tone, sexual function, urinary incontinence, impact of symptoms on the pelvic floor. Participants were randomized and allocated into three groups. Mixed linear models were used to evaluate the effects of interventions on pain, sexual function, incontinence, and the impact of symptoms on the pelvic floor, considering group and time as fixed factors. Bonferroni post-hoc was used to adjust for multiple comparisons. Results: 25 participants started the study (G1=8, G2=8, and G3=9), with six dropping out: one from G1, two from G2, and three from G3. Therefore, the retention rate was 76% (G1=87.5%, G2=75.0%, and G3=66.7%, p=0.615). Adherence did not differ between groups [G1: 100 (3)%; G2: 88 (25.0)%; G3: 100 (13)%, P=0.098], although two participants had adherence below 80% (75% and 62.5%). Pain reduction was observed in all groups, with no statistically significant differences between them. No statistically significant effects were observed in variables related to sexual function, urinary incontinence, impact of symptoms on the pelvic floor, or muscle tone (p>0.05 for all). Regarding muscle function, a time effect was observed, with participants increasing muscle function in all experimental groups, with no differences between them. Conclusion: The protocol's feasibility was adequate; however, the recruitment rate was low. Adherence to the protocol and retention of participants was generally adequate, with a need for strategies to reduce the risk of intervention dropout. Pain reduction occurred in all groups, with no statistically significant differences between the groups.