Hypothesis / aims of study
Gynecological cancer treatments often result in pelvic floor muscle (PFM) dysfunctions that could contribute to the development of pelvic floor disorders significantly affecting the quality of life of women and their partners (1). Although pain during sexual intercourse (dyspareunia) affects more than half of cancer survivors, very few evidence-based treatment options are available for this population. Prospective studies and randomized clinical trials support the effectiveness of physiotherapy (PT) which could be recommended as a first-line treatment for women suffering from vulvar pain with no history of cancer (2). Also, data in gynecological cancer survivors with dyspareunia are limited to a single prospective study conducted by our team. Statistically and clinically significant changes in pain symptoms and sexual function were found after PT treatment targeting PFM dysfunctions (3). However, there is a gap in knowledge about treatment mechanisms in this oncological population as no study thus far has investigated the changes in PFM function and morphology after PT treatment. Therefore, the aim of the study is to evaluate the effects of PT on PFM function and morphology in gynecological cancer survivors suffering from dyspareunia.
Study design, materials and methods
Data of this study were derived from the prospective study investigating the effects of PT in 31 gynecological cancer survivors with dyspareunia (endometrial cancer = 20 (64.5%), cervical cancer = 11 (35.5%)). Women were included if they had completed cancer treatments for at least three months and presented vulvovaginal pain (intensity of ≥5 on a numerical rating scale), for at least 80% of sexual intercourse attempts, for more than three months. A standardized pelvic examination was performed by a gynecologic oncologist from our team to confirm the eligibility of participants. PT treatment consisted of 12 weekly 1-hour sessions, including education, PFM exercises with biofeedback using an intra-vaginal probe, manual therapy such as stretching techniques, in addition to home exercises (five times per week). Participants were asked to refrain from using other treatments that could influence pain symptoms or PFM outcomes during their participation in the study.
Women underwent individual baseline and post-treatment assessments with an experienced physiotherapist not involved in the treatment. The physiotherapist taught the participant how to perform PFM contractions correctly. Then, the assessment of the PFM function and morphology was performed in a supine position after the participant had emptied her bladder.
PFM function was assessed using an intra-vaginal dynamometric speculum to measure the following five parameters. 1) Passive resistance at the minimal aperture (N). 2) Tissue flexibility in accordance to patient tolerance of the stretch to the maximal aperture (mm). 3) PFM maximal strength (N) according to a 10-s PFM maximum voluntary contraction (MVC). 4) PFM coordination, extracted from a 15-s rapid-repeated PFM MVCs, and described as the number of rapid contractions and speed of contraction (N/s). 5) PFM endurance using a 90-s sustained PFM MVC, defined as the normalized area under the force curve ([area/maximal force]·100) (%·s).
PFM morphology was evaluated with 3D/4D transperineal ultrasound imaging from GE Healthcare, model Voluson E8 Expert BT10 equipped with the convex probe RM6C. Measurements were taken in the mid-sagittal and axial planes under two conditions: rest and PFM MVC. The following six parameters were measured. 1) Bladder-neck (BN) position according to the horizontal (x-axis) and vertical position (y-axis) in cm. 2) Anorectal angle (°). 3) Levator plate angle (°). 4) Levator hiatal (LH) area (cm2). 5) LH anterior-posterior (AP) diameter (cm). 6) LH left-right (LR) diameter (cm).
PFM dynamometric and morphologic parameters were shown to be valid, reliable, and sensitive to change in previous studies with similar populations. All data analyses were processed offline. As data were normally distributed, paired t-tests were conducted to investigate the changes from baseline to post-treatment.
Participants’ mean age was 55.9 (SD 10.8), and body mass index was 28.5 (SD 5.3) kg/m2. Stages of cancer were 1 (n=19) (61%), 2 (n=6) (19%), 3 (n=5) (16%) and 4 (n=1) (3%). As for cancer treatments, 24 women (77%) had surgery (total hysterectomy and bilateral salpingo-oophorectomy=23, total hysterectomy=1), 19 (61%) had brachytherapy, 15 (48%) had external beam radiation therapy, and 16 (52%) had chemotherapy. The median of time since cancer treatments to baseline assessment was 38 months (quartile Q1=9, quartile Q3=70). Table 1 and Table 2 show PFM dynamometric and morphologic measures at baseline and post-treatment assessments. Of the 31 women assessed at baseline, one withdrew from the study (disease in the family) and two were lost at follow-up.
Interpretation of results
Significant changes in PFM function were found from baseline to post-treatment. Participants showed a reduction in passive resistance at the minimal aperture, an increase in tissue flexibility as well as improvements in PFM coordination and endurance. However, the change in PFM maximal strength from baseline was not statistically significant. This was expected as PT treatment emphasized muscle relaxation and motor control rather than strength training.
Regarding PFM morphology, results demonstrate significantly greater anorectal angle, smaller levator plate angle as well as larger LH dimensions at rest following PT, suggesting a lower PFM tone. At PFM MVC, the BN was positioned superiorly and anteriorly after PT. Furthermore, a significant decrease in LH area and LH AP diameter were detected.