Assessing multifactorial etiology of overactive bladder using a novel PFM-Hip-Trunk muscle network analysis - Abstract Interstitial cystitis/ bladder pain syndrome (IC/BPS) is one of the most debilitating chronic pelvic pain (CPP) conditions that negatively impacts the quality of life and sexual activities in 2.7% to 6.5% of women in the US. Pelvic floor muscle (PFM) overactivity, characterized by an increase in the tonic muscle activity, is a condition related to myofascial pain that presents in the majority of CPP conditions, including up to 85% of women with IC/BPS. However, pelvic floor pain is intrinsically a multifactorial dysfunction that is attributed to postural issues, myofascial trigger points, and abnormal muscle tone. Myofascial therapy, including specific pelvic floor muscle soft tissue mobilization and muscle stretching, is standard treatment for patients with IC/BPS and concomitant PFM tenderness. Unfortunately, even among IC/BPS patients with PFM tenderness on exam, only 59% of patients report symptom improvement after myofascial therapy. Pelvic floor myofascial therapy, however, does not address movement impairments of the trunk and hips, which are also associated with pelvic pain. A pelvic floor muscle phenotyping framework would allow IC/BPS patients to be categorized to facilitate individualized treatment. Unfortunately, no technology is currently available for quantitatively and objectively assessing PFM etiologic factors associated with IC/BPS, which, otherwise, would advance the understanding of the underlying mechanisms and allow for phenotyping patients for appropriate intervention. Our team has successfully 1) developed a novel intra-vaginal high-density surface electromyography (HD-sEMG) technique to reliably and quantitatively assess PFM overactivity in women with IC/BPS and 2) developed a novel muscle network analysis technique to reveal, for the first time, the inter-muscular connectivity pattern alterations among patients with neuromuscular conditions, and 3) demonstrated the feasibility to cluster patients with IC/BPS into phenotypic subgroups, depending on the underlying mechanism. This study aims to comprehensively assess the PFM overactivity, hip/trunk muscle activity alteration, PFM-to-Hip/ Trunk inter-muscular connectivity, and distinct PFM phenotypic subtypes in IC/BPS. This research represents the first effort to comprehensively assess the PFM overactivity, hip/trunk muscle activity alteration, PFM-to-Hip/Trunk inter-muscular connectivity, and distinct PFM phenotypic subtypes in IC/BPS. The integration of these multifactorial assessments will advance our understanding of the multifactorial pathology of IC/BPS. The quantification of relative importance of these pathological contributors will allow for IC/BPS patient phenotyping. Identification of PFM phenotypic subtypes may facilitate personalized physical therapy treatments.
