Hypothesis / aims of study
The objective of our study was to analyze the demographic and clinical characteristics of patients referred to a multidisciplinary chronic pelvic pain clinic and to evaluate the response to different types of minimally invasive techniques to treat pain. Additionally, we aimed to register any complications associated with these techniques.
Study design, materials and methods
Patients visited between January 2023 and January 2024 at a multidisciplinary chronic pelvic pain clinic, to receive treatment with minimally invasive techniques, were recruited. Demographic characteristics, time until referral to the multidisciplinary chronic pelvic pain clinic, follow-up at the unit, possible pain triggers, complementary examinations, injection technique, injected muscle, affected laterality, total number of injections during follow-up, diagnostic infiltration, injected drug, total infiltration points, percentage of pain reduction after injection, and complications were recorded.
Descriptive statistical analysis was performed.
Results
35 patients (33 women, mean age 49.41 years, range 29-80 years) were included. Mean body mass index was 23 kg/m2 (SD 2,75 kg/m2). Mean evolution time to be refered at the multidisplinicary chronic pelvic pain clinic was 51,9 months (range 4 to 252 months). Mean follow up at the unit was 24,5 months (range 5 to 96 months). The principal diagnoses were: myofascial pelvic pain syndrome (48.5%), painful scar and myofascial pelvic pain (22.8%), and neuropathic and myofascial pelvic pain (14.2%). Possible pain triggers included: gynecological surgery in 33.3%, obstetric history in 27%, and unknown etiology in 25.7% of patients. Additionally, 14.3% of patients presented urinary incontinence, and 11.4% both urinary and fecal incontinence. Complementary examinations performed were: gynecological ultrasound examination in 60% of patients, pelvic magnetic resonance imaging in 37.1% of patients, and endoanal ultrasound examination in 8.6% of patients.
97% of the patients received infiltrations under sedation. Regarding the type of infiltration: 62.8% of patients received myofascial injections, and 34.3% of patients received scar and myofascial infiltrations.
The most prevalent muscles injected were as follows: 85.7% puborectalis, 62.8% obturator internus, 54.2% iliococcygeus, 28.7% bulbospongiosus, 20% superficial transverse perineal, 8.57% anal sphincter, and 5.7% ischiocavernosus muscle.
85.7% of patients received bilateral injections, and the mean number of injections during follow-up was 2.37 (SD 1.49). Most patients (54.3%) received diagnostic infiltrations. The following injections were performed: botulinum toxin and local anesthetic in 48.6% of patients and botulinum toxin, local anesthetic, and hyaluronidase to treat scars in 20% of patients. The mean number of injection points was 4.3 (SD 1.58). The mean percentage reduction of pain was 65% (SD 27.7%). Regarding complications, 1 patient presented self-limited fecal incontinence.
Interpretation of results
Most of the patients under follow-up in the multidisciplinary chronic pelvic pain clinic are women with a very long history of pain. The most important diagnosis is myofascial pelvic pain syndrome, followed by painful scar added to myofascial pelvic pain. The most frequent medical history and possible pain triggers are gynecological surgery and obstetric history, but in a relevant percentage of patients, the etiology is unknown. The majority of patients received myofascial injections under sedation, and the puborectalis, internal obturator, and iliococcygeus muscles are the most frequently injected. The majority of patients presented bilateral pain. Botulinum toxin and local anesthetic injections are the most prevalent performed. A mean of 4 injection points are needed per patient. Patients reported a significant reduction of pain after injections, and the complication rate is low.