Pudendal Neuralgia
The pudendal nerves are mixed nerves, with predominant sensory supply to the pelvic floor, external genitalia and perineum. Pudendal neuralgia is chronic pelvic floor pain involving the pudendal nerves. This pain may first occur after childbirth, but often waxes and wanes without reason.
Epidemiology
The prevalence of PFD increases steadily with age. With improved life expectancy, the prevalence and burden of the disorder is bound to increase. The burden of the disease is perceived not just at an individual level but healthcare providers also are affected and the impact on healthcare is likely to increase.
Pelvic Organ Prolapse
About 316 million women suffer from genital prolapse worldwide. Based solely on patient symptoms, the prevalence of pelvic organ prolapse (POP) is 3–6%; however, it rises up to 50% if based on clinical examination because most of the mild cases are asymptomatic. According to the Women's Health Initiative (WHI) in the United States, 40% of women have some degree of POP with 14% having uterine prolapse. The incidence of POP surgery varies from 1.5–1.8 per 1000‐woman years with peak age at 60–69. The probability of having a surgical correction for POP by age 80 is estimated to be one in five.
Based on the WHI data, incidence of stage 1–3 prolapse is estimated to be 9.3 per 100 woman‐years for cystocele, 5.7 per 100 woman‐years for rectocele, and 1.5 per100 woman‐years for uterine prolapse. Prolapse progression ranged from 1.9% for uterine prolapse, to 9.5% for cystocele, and 14% for rectocele. Older, parous women are more likely to develop new or progressive prolapse.
In the United States, POP is thought to be the leading cause of more than 300 000 surgical procedures per year with 25% undergoing reoperations at a total cost of more than one billion dollars annually. The estimated direct annual cost of ambulatory care utilisation for pelvic floor disorders during a nine‐year period (1996–2005) increased by 40% and, if extrapolated to POP surgery, the total annual cost would be over 1.4 billion.
Urinary Incontinence
UI is more common in women than men and studies from numerous countries have reported the prevalence of UI in women to range from approximately 5–70%, with most studies reporting a prevalence of any UI in the range of 25–45%. In nonpregnant women aged 20 years and above, the prevalence has been reported at 10–17%. These figures increase with increasing age, and in women 65 years and older, more than 50% of the population is affected. The estimated cost of UUI with OAB in the United States during 2007 was $65.9 billion, with projected costs of $76.2 billion in 2015 and $82.6 billion in 2020. With the addition of SUI, this figure may be higher.
Anal Incontinence
The prevalence and epidemiology of anal incontinence is poorly documented and under‐reported by patients primarily due to embarrassment and concerns regarding treatment options. The prevalence of faecal incontinence in American women is estimated to impact 2.2–24% depending on the definition used. Severe faecal incontinence, defined as incontinence greater than or equal to one episode monthly, is reported to be present in 6.3% of women.
Furthermore, obstetric anal sphincter injuries in vaginal births are serious complications that share a well‐known association with anal incontinence. Injury to the anal sphincter during childbirth approximately doubles the risk of developing anal incontinence within six months after a first delivery.
Predisposing Factors
Genetic predisposition: Women with prolapse were more likely to have positive family history and an increased prevalence of congenital weakness of connective tissue. A systematic review of genetic studies found that collagen type 3 alpha 1 was associated with POP (OR 4.79).
Age: According to The National Institute of Health study, the prevalence of PFD varies from 10% at ages 20–39 years, 27% at 40–59 years, 37% at 60–79 years to nearly 50% affected at 80 years of age and older. The US National Health and Nutrition Examination Survey 2005–2010 stated that the prevalence of faecal incontinence increased from 2.91% among the 20–29 years old to 16.16% among participants 70 years and older.
Race: Although the evidence is scarce, Latin and Caucasian women were found to have a higher risk of symptomatic POP as compared to African American women. Similarly, the age‐adjusted prevalence of weekly UI varied based on ethnicity. Hispanic women had the highest rates, followed by white, black, and Asian American women (36, 30, 25, and 19% respectively, p > 0.001). It may be important to note the bias due to the impact of culture‐based differences in perception of symptoms.
Obesity: Increased body mass index (BMI) is an independent risk factor for pelvic floor disorders and progression of POP. Weight loss has not been associated with prolapse resolution, but studies have shown that weight loss through lifestyle changes and/or bariatric surgery in overweight or obese women improves both urinary and faecal incontinence.
Parity: Though vaginal birth has been considered the most important inciting factor for pelvic floor disorders, pregnancy itself has been shown to be a risk factor. Studies have shown a direct correlation between the incidence of pelvic floor disorders and parity: 12.8, 18.4, 24.6, and 32.4 for 0, 1, 2, and 3 or more deliveries, respectively (P < 0.001). Operative vaginal deliveries and perineal lacerations increase the risk further. Spontaneous vaginal birth as compared to caesarean birth without labour has been associated with higher rates of prolapse or stress incontinence.
Smoking: The Pelvic Organ Support Study (POSST) 2005, revealed that smoking was an independent risk factor for pelvic disorders including POP and UI. The prevalence of prolapse increased significantly amongst nulliparous smokers as compared to nulliparous non‐smokers (28vs 12%, adjusted OR 1.95).
Medical disorders: Studies have shown an association between pelvic floor disorders and various medical conditions including diabetes mellitus, connective tissue disorders, chronic obstructive pulmonary disease (COPD), and certain neurological diseases.
Coexisting pelvic floor disorders: Pelvic floor disorders often coexist. Patients with POP often complain of SUI due to obvious reasons. It is often difficult to find patients with any one form of incontinence as most patients have concurrent stress and urge incontinence. Therefore, it is important to analyse these patients thoroughly before formulating a treatment plan.
Others: Traumatic injury to the pelvic region including injuries due to pelvic surgery or pelvic irradiation and heavy lifting are associated with PFD.
Pelvic Organ Support
Pelvic Floor
The pelvic floor consists of muscular and fascial structures. It encloses the pelvic cavity, the external vaginal opening (for intercourse and parturition), and the urethra and rectum (for elimination). The pelvic muscles provide the primary support and with the connective tissue (endopelvic fascia) keep pelvic organs in proper alignment. Together they stabilise, support, and also help in appropriate functioning of the pelvic organs. A sound understanding of the clinical relevance of the bony, muscular, and fascial supports is vital to optimise the surgical techniques in pelvic surgery.
Muscular Support
The levator ani muscle and associated connective tissue attachments constitutes the pelvic diaphragm. It has two main components that function as a unit: the diaphragmatic part (iliococcygeus and coccygeus muscles) and the pubovisceral part (puborectalis and pubococcygeus). The pelvic diaphragm is stretched like a hammock from pubis to coccyx and is attached along the lateral pelvic walls to a thickened band in the obturator fascia, the arcus tendineus levator ani (ATLA).
The iliococcygeus spans from the