Clinical Effectiveness of Trigger-Point Injections for Myofascial Pelvic Pain in Endometriosis

INTRODUCTION: Chronic pelvic pain affects approximately 20–60% of women and can significantly impact patients’ quality of life. Trigger-point injections with local anesthetic have been shown to improve patients’ pain symptoms in multiple research studies and clinical trials. However, there is limited to no evidence examining or evaluating patient satisfaction and clinical response to trigger-point injections. OBJECTIVE: The aim of this study is to investigate the clinical response and patient satisfaction after trigger-point injections (TPIs) for pelvic floor tension myalgia in patients with endometriosis unresponsive to pelvic floor physical therapy and oral or vaginal pain management. METHODS: This is a retrospective review of women undergoing in-office TPIs at a tertiary academic medical center located in Florida. All patients 18 years and older who underwent TPIs in the office between May 2021 and December 31, 2024. Patient’s pain symptoms were assessed in the office or via telephone via a pain survey, a questionnaire consisting of five questions. We excluded patients who did not have a pain survey performed. RESULTS: In this retrospective study, a total of 66 patients underwent a total of 82 pelvic floor trigger-point injections. Of the total cohort, 34% (n=28) of injections were performed in subjects with a diagnosis of endometriosis. Mean age of the entire group was 51 years old and significantly younger in women with endometriosis (44 years old vs 54 years old, p=0.013). When queried, 80.5% of patients responded that their pain improved after trigger-point injections and 69.2% of patients were satisfied with their results. Clinical pain numerical rating scale (NPRS) scores were reduced significantly post-procedure (p=0.009) in women with endometriosis. Patients with and without endometriosis were equally satisfied with trigger-point treatment; however, patients with endometriosis were less likely to report subjective pain improvement (p=0.008). CONCLUSIONS: Women with endometriosis were less likely to report subjective improvement in pain after pelvic floor TPIs, even though they were satisfied with treatment and their clinical NPRS scores improved. This initial exploratory analysis can provide guidance on treatment options and counseling for patients with chronic pelvic pain and endometriosis, specifically regarding expectations.