This study is being done to better understand and improve treatment for myofascial pelvic pain, a common cause of long-lasting pelvic pain in women. Myofascial pelvic pain is related to tight or dysfunctional pelvic floor muscles and can cause pain as well as bladder, bowel, and sexual problems. Current clinical evaluations mostly rely on physical examination and patient-reported symptoms and do not fully measure how the pelvic floor muscles are functioning.

The purpose of this study is to measure pelvic floor muscle function using a noninvasive imaging method called near-infrared spectroscopy, or NIRS. This method measures changes in muscle blood flow and oxygen levels during muscle contraction and relaxation. The study will examine whether pelvic floor muscle function improves after different treatments and whether these physiologic changes are associated with improvements in pain and symptoms.

The study will enroll 120 adult women who have had pelvic pain for at least three months and have pelvic floor muscle tenderness on examination. Participants will be randomly assigned to one of three groups: education with relaxation exercises, pelvic floor physical therapy focused on myofascial release, or vaginal medication used to help relax pelvic floor muscles.

Participants will take part in four study visits over a six-month period. During these visits, they will complete questionnaires about pain and pelvic symptoms, undergo pelvic floor examinations, and have pelvic floor muscle imaging using the NIRS device while performing brief muscle contractions and relaxations. Some visits will also include collection of blood, urine, and vaginal samples to measure inflammation.

The information gained from this study may help improve the diagnosis and treatment of myofascial pelvic pain by providing objective measures of pelvic floor muscle function and identifying which treatments are most effective for different patients.

STUDY OVERVIEW This is a prospective, randomized, controlled clinical study designed to objectively measure pelvic floor muscle (PFM) physiology and inflammatory changes in women with myofascial pelvic pain (MPP). The study uses a novel, transvaginal near-infrared spectroscopy (NIRS) system to assess pelvic floor muscle oxygenation, hemodynamics, and recovery during standardized contraction and relaxation tasks. The overarching goal is to improve objective diagnosis, phenotyping, and personalized treatment of MPP.

Scientific Rationale Myofascial pelvic pain is a common contributor to chronic pelvic pain in women and is characterized by pelvic floor muscle hypertonicity, impaired muscle perfusion, local acidosis, and accumulation of inflammatory mediators. These physiologic abnormalities contribute to pain as well as bladder, bowel, and sexual dysfunction. Current clinical evaluation relies largely on subjective examination and patient-reported symptoms, which limits precision in diagnosis and treatment selection.

Preliminary work has demonstrated that pelvic floor NIRS imaging can reliably distinguish women with MPP from asymptomatic controls and can identify physiologic impairments such as reduced muscle oxygenation and delayed recovery following contraction. This study evaluates whether targeted myofascial therapies improve these objective physiologic measures and whether changes in muscle physiology correlate with symptom improvement and inflammatory biomarkers.

STUDY OBJECTIVES

Primary Objective To determine whether pelvic floor muscle fitness, measured using NIRS-derived oxygenation parameters, improves following myofascial-directed treatments in women with MPP.

Secondary Objectives To characterize NIRS-derived physiologic patterns associated with symptom severity and pelvic floor dysfunction.

To assess relationships between NIRS measures and systemic and local inflammatory biomarkers.

To identify physiologic predictors of treatment response using machine-learning-based analytic approaches.

STUDY DESIGN

Design: Prospective, randomized, controlled trial

Sample size: 120 adult women with myofascial pelvic pain

Randomization: 1:1:1 allocation

Treatment arms:

Education and generalized relaxation (control) Myofascially-directed pelvic floor physical therapy Pharmacologic pelvic floor muscle relaxation

Study duration: Six months per participant

Study visits: Baseline, 1-2 weeks, 3 months, and 6 months

Total participant time: Approximately four hours across all visits

STUDY PROCEDURES

Baseline Visit After informed consent, participants complete validated questionnaires assessing pelvic pain, urinary, bowel, sexual function, psychological symptoms, and quality of life. Participants also complete two 24-hour bladder and bowel diaries.

Clinical assessments include urinalysis and post-void residual if not recently documented, standardized pelvic examination with grading of muscle strength and myofascial tenderness, perineometry, surface electromyography, and bulbospongiosus reflex testing. Pelvic floor NIRS imaging is performed transvaginally during a guided 10-minute protocol involving repeated contraction and relaxation exercises, capturing real-time oxygenated and deoxygenated hemoglobin data across multiple circumferential channels.

Biologic specimens, including blood, urine, and vaginal samples, are collected for inflammatory biomarker analysis.

Follow-Up Assessments Participants return at 1-2 weeks, 3 months, and 6 months to repeat symptom questionnaires, bladder and bowel diaries, pelvic floor examination, and NIRS imaging. Participants also complete a patient global impression of improvement assessment at all visits after treatment. Biologic specimen collection is repeated at the early post-treatment visit.

DATA MANAGEMENT AND SAFETY

All study data are collected and managed using secure, HIPAA-compliant electronic data capture systems. Data are de-identified at the time of entry. An independent monitoring process oversees recruitment, protocol adherence, and adverse events. All study procedures are considered minimal risk and consistent with standard gynecologic and pelvic floor physical therapy care.

Inclusion Criteria:

Women over 18 years of age

Pelvic Pain for more than 3 months

Report an average daily pain intensity score of at least 4 on a 0 to 10 scale

Palpable trigger/tender points in internal pelvic floor muscles on standardized myofascial pelvic floor exam

Willing to refrain from new clinical treatment that may affect pain during the study period

Exclusion Criteria

Inability to participate in clinic visits

Prior invasive pelvic procedures for pain (e.g., prior pelvic surgery, sacral neuromodulation, intradetrusor Botox®) in the past 6 months

Active UTI or vaginal infection

Pregnancy or childbirth in the past 12 months, currently planning a pregnancy

Illicit Drug addiction/regular use of controlled substances (including marijuana use in the past 2 weeks or during the study period)

Pelvic floor physical therapy in the past 3 months

Malignancy or other serious medical condition (e.g., poorly controlled diabetes [HgA1c > 8], chronic renal disease [GFR <30], neurologic or rheumatic disease)

Diagnosed with an alternate cause of pelvic pain (e.g., ulcerative interstitial cystitis, vestibulodynia, vulvar dermatoses, dysmenorrhea)

Urinary retention with a PVR >150 mL

Greater than stage 3 pelvic organ prolapse

Indwelling vaginal devices (e.g., pessary, contraceptive ring. Not including Mirena IUD) that cannot be removed for the study

Inability to sign an informed consent, fill out questionnaires, or complete study interviews

De-identified individual participant data (IPD) underlying published results will be shared with qualified researchers upon reasonable request. Data will be de-identified in accordance with applicable privacy regulations and institutional policies. Requests for data access must include a brief description of the proposed research, planned analyses, and data protection measures, and will be reviewed by the study investigators. Data will be shared through a secure data transfer mechanism following execution of an appropriate data use agreement. Data will be available beginning after publication of the primary study results and will remain available for a defined period consistent with institutional and funding agency requirements.

De-identified individual participant data (IPD) and supporting documents will be available beginning after publication of the primary study results. Data and supporting information will remain available for up to five years following publication, or longer as required by institutional and funding agency data-sharing policies.

Access to de-identified individual participant data and supporting information will be provided to qualified researchers upon reasonable request. Researchers must submit a written proposal describing the research question, planned analyses, and data security measures. Requests will be reviewed and approved by the study investigators. Data and documents will be shared only after execution of an appropriate data use agreement and will be provided via secure electronic file transfer. Shared materials will include only de-identified data and redacted documents necessary to support the approved research purpose.