Hypothesis / aims of study
Pelvic floor myofascial pain (PFMP), defined as tenderness and trigger points in the levator ani (LA) and obturator internus (OI) muscles, is prevalent among women with pelvic floor disorders. Current management options are associated with side effects and are not always accessible or covered by insurance. Cryotherapy has been shown to improve myofascial pain elsewhere in the body; therefore, vaginal cryotherapy may be a promising alternative treatment for PFMP. In the present pilot randomized controlled trial, we sought to determine the effect of vaginal cryotherapy on PFMP and pelvic floor symptoms.
Study design, materials and methods
Following a standardized PFMP screening exam, eligible participants with a pain score ≥4/10 in ≥1 of 4 muscle groups were invited to participate in a randomized controlled trial, comparing cryotherapy (15 mL centrifuge tube prepared with 10 mL tap water and 5 mL 70% isopropyl alcohol) to a control (empty 15 mL centrifuge tube at room temperature). Participants in both arms could select to participate in a one-time in-office treatment, an at-home two-week daily treatment, or both. Participants in the in-office group were instructed to place the assigned tube intravaginally for 10 minutes and were immediately reexamined. At-home therapy participants were instructed to perform the intervention daily for 10 minutes for 2 weeks or until their follow-up appointment. T-tests and Wilcoxon rank-sum tests were used to compare changes in pain scores between arms. At-home participants completed baseline and follow-up Urogenital Distress Inventory-19 (UDI-19), Pelvic Floor Distress Inventory short form (PFDI-20) comprised of Pelvic Organ Prolapse Distress Inventory (POPDI-6), Urogenital Distress Inventory (UDI-6), Colorectal-Anal Distress Inventory (CRADI-8), and Patient Global Impression of Improvement (PGI-I).
Results
Between 3/2019-9/2021, 164 participants were enrolled and randomized: 81 to cryotherapy and 83 to control. A total of 64 (30 cryotherapy; 34 control) completed the in-office treatment and 56 (32 cryotherapy; 24 control) completed the at-home, two-week treatment. Most participants identified as Caucasian (85.4%) with mean age of 53.6±15.1 years and reported lower urinary tract symptoms (LUTS) (90.2%, mean baseline UDI score=111±56.3). In the in-office comparison, mean pain scores decreased significantly in both arms: cryotherapy (5.00 vs 3.99; p=0.02) and control (5.69 vs 4.84; p<0.01), with a similar magnitude of reduction between arms (p=0.61). In the at-home comparison, mean pain scores decreased significantly in the cryotherapy arm (6.31 vs. 4.72; p<0.01), and non-significantly in the control arm (5.50 vs. 4.74; p=0.06), resulting in a non-significant difference in mean pain score change between arms (p=0.14; table1.0). At-home cryotherapy participants reported an overall improvement in UDI-19, PFD-20, and PGI-I scores, with significant differences between arms noted for POPDI-6 (-12.9 vs. 2.4; p=0.03; table 2.0) and PGI-I scores (3 (a little better) vs. 4 (No change); p≤0.01).
Interpretation of results
PFMP pain scores improved following both short-term cold and room temperature intravaginal therapy, as well as following two weeks of cryotherapy. Interestingly, two-week cryotherapy participants reported improvement in LUTS and prolapse symptoms. Whether these findings reflect a therapeutic effect of both cold and room temperature intravaginal therapy, or a placebo effect is unclear but should be explored in larger studies.