Hypothesis and background: Myofascial pelvic pain (MPP) causes discomfort within the muscles of the pelvic floor and connecting fascial structures. This condition can significantly impede pelvic functionality. Yet, there’s a paucity of empirical evidence scrutinizing the efficacy of medical approaches addressing it.
Presently, certain Canadian centers are administering a new off-label formulation comprising Baclofen Gabapentin for myofascial pain, particularly in women with pelvic floor muscle-related myofascial pain, yielding anecdotal reports of positive outcomes.
Baclofen is a skeletal muscle relaxant often used for the management of neurological spasticity, and Gabapentin is a neuromodulator that induces soft tissue relaxation and mitigates associated pain. Both medications have shown primitive results supporting their use in chronic pelvic pain. 
We hypothesize that given the pharmacological properties of both medications and the anecdotal evidence of their benefit, there would be empirical evidence of their efficacy in treating MPP. 


Aims: The primary aim of this study is to evaluate the effectiveness and safety of Baclofen/Gabapentin suppositories (BGS) in alleviating pain, improving sexual function, and enhancing the quality of life among patients with myofascial pelvic pain who have been prescribed these suppositories as part of their standard care. 
Our secondary objective involves collecting data that will inform sample size calculations for a future randomized controlled trial (RCT) on this subject.

A retrospective chart review was conducted for individuals prescribed BGS for myofascial pain as part of their standard care in our clinic. Eligibility screening encompassed all patients from 2017 until the study's inception. 
Inclusion criteria comprised females aged 18 and above, proficient in English, diagnosed with myofascial pelvic pain, and prescribed BGS. Exclusions encompassed non-consenting patients and pregnant patients. 
The primary outcome was changes in pain levels and intensity, measured through the Visual Analog Scale (VAS), while secondary outcomes included alterations in quality of life, pelvic health, and sexual function measured via the Pain Catastrophizing Scale (PCS), McGill Pain Questionnaire (MPQ), Pelvic Floor Distress Inventory-20 (PFDI-20), and Female Sexual Function Index (FSFI). 
Statistical analyses employed means with standard deviations and medians with interquartile ranges. Paired T-test and Wilcoxon Signed Ranks test were used to analyze the primary and secondary outcomes. The MPQ results were collected for descriptive purposes and were not included in the final analysis plan. A 2-sided p-value of <0.05 was used for statistical significance.

A series of 35 patients meeting our predefined inclusion criteria participated in our study. Demographic details of the patients are presented in Table 1, while baseline medical and gynecological conditions are outlined in Table 2.
Our study unveiled that patients endured MPP for extended durations (mean 7.5 years, SD +/- 8.5 years), with some individuals experiencing symptoms for more than a decade. Notably, 57% of the patients experienced an unprovoked onset of MPP, while 42% developed MPP subsequent to a pathological condition or surgical intervention. Following its onset, MPP exerted a substantial impact on the quality of life, prompting 20% of patients (n=7) to discontinue work due to pain.
Prior to initiating BGS treatment, patients in our study explored various pain management modalities. Specifically, 77% (n=27) engaged in pelvic physiotherapy, 42.8% (n=15) experimented with alternative medicine approaches, 17% (n=6) underwent surgical interventions, 5.7% (n=2) received pudendal nerve blocks, and 5.7% (n=2) resorted to opioid usage.
All patients diagnosed with MPP in our study received BGS treatment. The average duration of BGS therapy among our cohort was 15 months (SD +/- 8 months), ranging from 2 to 36 months. After the start of the BGS, several primary outcome questions demonstrated a significant improvement in VAS scores at the 1-year follow-up compared to baseline. Upon inquiry regarding their "current pain level," participants exhibited a noteworthy reduction in mean VAS scores, decreasing from a baseline mean of 3 to 1 after one year (p-value <0.0001). A parallel trend was observed in responses to a query about "worst pain," where the mean VAS decreased from 5.3 at baseline to 5.0 at the 1-year mark (p-value 0.02). Conversely, inquiries regarding pain intensity failed to reveal a statistically significant change in VAS scores from baseline to the 1-year follow-up. In terms of pain control, the two patients that used opioids at baseline, stopped using them after starting the BGS.
The secondary outcome encompassed several standardized questionnaires. The PCS demonstrated a significant improvement, with mean scores decreasing from 41.97 at baseline to 33.57 at 1-year follow-up (p-value 0.0008). Conversely, PFDI-20 scores and its subdomains, as well as FSFI scores, did not exhibit statistically significant changes between baseline and 1-year follow-up. PFDI-20 median scores remained constant at 150 (p-value 0.83), while FSFI mean values showed no significant shift (22.5 at baseline and 24.0 at 1-year, p-value 0.59).

Our study highlights the prolonged suffering experienced by individuals with myofascial pain, potentially attributed to the vague symptomatology, diagnostic challenges, and the dearth of scientifically robust management strategies. Our results showed that the off-label application of BGS demonstrated substantial improvements in MPP, as evidenced by VAS and PCS scores. These findings hold promise for individuals affected by CPP of myofascial origin.
Although existing literature extensively supports the efficacy of Baclofen and Gabapentin in managing pain, their application in CPP remains relatively limited. Our results align with the previous recommendations on using Baclofen for CPP. Although, the previous literature focused on male subjects, our study is reporting improvement with the use of Baclofen in female subjects. The results also align with larger body of evidence showing the benefits of Gabapentin in CPP. Our results are consolidating the literature on the Baclofen and Gabapentin utility for CPP and advocating for more comprehensive data.
Given the predominant pain modulatory actions of Baclofen and Gabapentin, the lack of discernible influence on pelvic and sexual functions, as indicated by PFDI and FSFI results, was anticipated. While our hypothesis envisioned improvements in muscular relaxation and neuromodulation, these findings underscore the need for further exploration and elucidation of the multifaceted impacts of these medications on pelvic and sexual functions.

The BGS shows promise as an intervention for females suffering from MPP and warrants consideration for patients with this condition. However, further rigorous clinical trials are necessary to establish comprehensive global recommendations for the use of this intervention.