The Effect of Preoperative Pelvic Floor Physical Therapy (Prehabilitation) on Postoperative Pain Following Endometriosis Surgery: A Randomized Controlled Trial

Introduction: Endometriosis is a chronic inflammatory gynecologic condition characterized by growth of ectopic endometrial-like tissue within and outside of the pelvis, and is a common cause of chronic pelvic pain. Surgical management, including fertility-sparing endometriosis surgery or hysterectomy, is frequently performed with the goal of improving pain and quality of life; however, persistent or recurrent pain after endometriosis surgery is not uncommon. Factors contributing to ongoing pain may include conditions that are present before surgery including myofascial pelvic pain, psychological factors, or the presence of other comorbid chronic pain conditions, sometimes culminating in complex pain syndromes and central nervous system sensitization. "Prehabilitation", defined a structured intervention such as physiotherapy, exercise, and dietary changes, have been shown to improve perioperative outcomes in several surgical specialties, including gynecologic oncology, colorectal surgery, and orthopedic surgery. Pelvic floor physiotherapy has been shown to improve endometriosis-related pain symptoms and functional outcomes. Despite indirect data showing benefits, the quantitative and qualitative effect of prehabilitation in individuals undergoing endometriosis surgery for pelvic pain remains unknown.

Aim: To investigate the impact of structured preoperative pelvic physiotherapy in patients with pelvic pain undergoing endometriosis surgery (fertility sparing surgery and hysterectomy)

Objectives:

• Determine the effect of pelvic physiotherapy prehabilitation on quality of life, measured by Endometriosis Health Profile (EHP)-30 scale (primary outcome)
• Examine the impact of pelvic physiotherapy prehabilitation on chronic pelvic, dysmenorrhea, dyspareunia, symptoms of irritable bowel syndrome (IBS) and painful bladder syndrome (PBS), and psychologic indices including depression, anxiety and pain catastrophizing (secondary outcomes) Hypothesis: Patients receiving structured preoperative pelvic floor physiotherapy ("prehabilitation") will have improved post-operative pain scores and improved quality of life compared to those receiving standard care.

Methods: This study is a prospective, single-center, double arm, non-blinded randomized controlled trial evaluating the effect of preoperative pelvic floor physiotherapy ("prehabilitation") on pre- and post- operative pain and quality of life outcomes in patients with pelvic pain undergoing surgery for endometriosis (fertility sparing or hysterectomy). Participants aged 18-50 will be screened for eligibility from the Chronic Pelvic Pain (CPP) clinic in Edmonton, Alberta at the Lois Hole Hospital for Women. Eligible and willing participants will undergo randomization in a 1:1 ratio to receive either structured preoperative pelvic floor physiotherapy (2-3 sessions within 6 months leading up to surgery), in addition to standard perioperative care (intervention group) or standard perioperative care alone (control group). Surgery will be performed by fellowship trained minimally invasive gynecologic surgeons at the Royal Alexandra Hospital in Edmonton, AB. Participants will complete questionnaires at baseline, after prehabilitation is complete before surgery, 6-8 weeks post operatively, and 6 months and 12 months post operatively. Baseline demographic information will be collected including age, BMI, gynecologic surgical history, hormone use, and analgesic use. The primary outcome measure of this study is the Endometriosis Health Profile (EHP)-30 score (measures quality of life) over these timepoints. Secondary outcomes include measurements of chronic pelvic pain, dysmenorrhea, dyspareunia (numerical rating scale), presence of IBS and PBS, Central Sensitization Inventory (CSI), Pain Catastrophizing Scale (PCS), and assessment for depression through the Patient Health Questionnaire-9 (PHQ-9), and presence of generalized anxiety disorder through the GAD-7 questionnaire. Data will be stratified by the type of surgery patients received (hysterectomy or fertility-sparing endometriosis surgery) and stage of endometriosis (stage I/II or stage III/IV).

Expected outcomes and significance: If effective, preoperative pelvic floor physiotherapy may represent a low-risk intervention to improve overall pain and quality of life in patients undergoing endometriosis surgery. Findings could inform the creation of standardized care pathways for patients seeking care for chronic pelvic pain, improve outcomes in patients undergoing surgery for endometriosis, and decrease healthcare utilization after surgery which could have a major positive economic impact as well.

Inclusion criteria

• Presence of chronic pelvic pain (>6 months)
• Diagnosis of endometriosis (clinical, laparoscopic, or imaging-based diagnosis)
• Scheduled for fertility-sparing endometriosis surgery or hysterectomy with excision of endometriosis

Exclusion criteria

• Undergoing gynecologic surgery in the absence of pelvic pain
• Patients undergoing laparotomy or conversion to laparotomy
• Have undergone endometriosis related surgery in the past 12 months
• Have engaged in pelvic physiotherapy in the past 12 months
• Non-English speakers (if validated tools unavailable)
• Active malignancy
• Post-menopausal
• Prior oophorectomy
• Prior hysterectomy