Pelvic Floor Physiology Research Articles

Parks retractor.

The use of a surgical speculum (latin for mirror, from specere: to watch) or retractor has been described since ancient times. An anal speculum (catopter) for haemorrhoids, abscesses, and fistulas was mentioned in Hippocrates’ dissertations from around 400 BC1. Many years followed without further advances in transanal surgery owing to pain, limited anaesthesia, morbidity, and even death2. Perhaps the most famous fistulotomy in history (1685) necessitated the development of new instruments, when King Louis XIV had an anal fistula treated by the ‘barber surgeon’ Charles-Francois Felix. He spent months developing new instruments and refining his technique by undertaking ‘surgical training’ on guinea pigs and less well-to-do patients. Among these instruments was a three-bladed self-retaining anal retractor (Fig. 1a), a predecessor of the retractor described in this article. The evolving interest in, and optimization of, transanal excisions of anal and rectal tumours at the beginning of the 20th century demanded improved access to, and visualization of, the rectum. In Benign Tumours of the Rectum3, Alan Guyatt Parks (1920–1988) described and illustrated the use of a two-bladed self-retaining speculum for excision of rectal adenomas. A three-bladed version (Parks retractor) (Fig. 1b) was described in a later article in 19734. It formed the basis of two principles essential for peranal excision: that the anal canal could be opened to achieve exposure with the retractor, and that submucosal injection facilitated dissection. As Parks stated, the key to optimal surgery is ‘good exposure, good exposure, good exposure’5. Parks had many other innovations and contributions from the aetiology and classification of anal fistula to pelvic floor physiology, haemorrhoid surgery, and ileal reservoir with ileoanal anastomosis6.

Adolescent inguinal hernia repair: a review of the literature and recommendations for selective management.

The choice of how to repair inguinal hernias in adolescents has historically been a matter of experience and differed between pediatric surgeons who traditionally performed a high ligation of the sac and general surgeons who typically perform a repair using mesh. This up-to-date review thoroughly examines the subject and discusses the suitability of both types of repairs in this unique age group. A 20-year Pub Med search was performed for the following terms: adolescent hernia repair including reports of mesh hernia repair in adolescents and postoperative complications including chronic inguinal pain and recurrences. The evidence in the literature suggests that while there appears to be no difference between the two types of repairs with regards to recurrence and complications, changes in the pelvic floor physiology in adolescents suggest that a selective, individualized approach can be recommended depending on the size and nature of the presenting pathology. A selective approach to the inguinal hernia in adolescent patients based on the size of the defect appears justified.

Utilization of sexual health and pelvic floor physiotherapy services in Vancouver’s Prostate Cancer Supportive Care (PCSC) Program.

163 Background: The Vancouver Prostate Centre established PCSC in January 2013 to provide education and clinical services to men with prostate cancer (pts) and their partners. The program includes a dedicated sexual health (SH) clinician and physiotherapist (PT) with expertise in male pelvic floor anatomy and physiology. Educational and clinical services are available to pts without charge. We examined the use of the SH and PT services in PCSC to better understand how the services are utilized. Methods: Pts who are pre-treatment or within 6 months of surgery or radiation are offered a group educational (ED) session regarding sexual rehabilitation with the option of visits to the SH clinic. Those who were > 6 months from surgery or radiation were offered evaluation in the SH clinic. Pts who are about to undergo surgery or who have postoperative incontinence are offered attendance at a group ED session and/or 3 visits with the PT clinician. We gathered data from PCSC logs, clinic schedules, and patient records to assess utilization of SH and PT services. Results: SH and PT ED sessions and clinics (CLIN) were initiated in July and October 2013 respectively. Of 802 pts oriented to PCSC, 400 pts, median age 64 (42-92), participated in the SH module and 229, median age 66 (range 42-88) in the PT module. 90% of patients in each module had been treated with surgery; 10% were on ADT. Details of utilization of the ED and CLIN components by pts for both modules are shown in the table below. There was a total of 781 SH clinic visits: 141 pts had one visit, the remainder had a median of 3 visits (range 2-8). For PT, there were 334 visits, with a median of 2 (range 1-4) per pt. 37% of pts who were seen by SH were also seen by PT and 65% of those seen in PT were seen in SH. Conclusions: Sexual dysfunction and urinary incontinence can be significant problems, and often occur together. The PCSC Program offers both educational and clinical services to address these issues, and continues to modify its programs to best serve patient and partner needs at various time points after therapy. [Table: see text]

Cellular modelling in functional tissue engineering: review oriented for pelvic floor dysfunctions

This paper aims to review the current strategies for pelvic floor dysfunctions (PFDs). PFDs, such as stress urinary incontinence, foecal incontinence and vaginal prolapse affect the quality of life in women, involve high healthcare costs, and pose poor long-term success rates. As the problem progresses the cells in the pelvic tissues are impaired. The rheological relations between PFD and the damage of the tissues is not yet well established, bringing out clinical repair interventions, instead of knowing the root problem. As a consequence, the verification of damage mechanisms in the pelvic structures should be observed at cellular scales to correlate with the macroscopic phenomenological pathologies, namely, the changes in the mechanical properties and on the geometric configuration of the pelvic structures. Cells sense mechanical stimuli and respond biochemically via mechanotransduction mechanisms. Therefore, investigations on the cell dynamics must be performed, considering the physical conditions inside the bioreactors, to shed insight into the active behaviour of the cells during the treatment. These investigations should establish the conditions that push a cell to or keep a cell in a desired state during a regenerative treatment. This paper reviews the use of human adult stem cells to regenerate the defective muscles, ligaments and connective tissues in the pelvic floor, focusing on the role of the computational models as an assistive technology for these emergent tissue engineering treatments. First, the pelvic floor anatomy and physiology is related with the kinematic and mechanical behaviour of those structures at the tissue and cell scales. After, the relevance of the regenerative treatments is discussed and the requirements for their application are summarised. Later, the developments on computational models are exposed and the main guidelines for regeneration of the pelvic cavity tissues are proposed.

Impact of pregnancy and parturition on the anal sphincters and pelvic floor

Incontinence and defecatory difficulties are commonly reported among women and are often ascribed to traumas sustained during childbirth. Specifically, injuries to the anal sphincters (tears) and conformational changes in the various structures that comprise the pelvic floor (prolapse and perineal descent) have been considered as important contributors to the development of anal incontinence, or difficult defaecation (straining, incomplete evacuation), in later life. An understanding of both the effects of pregnancy and parturition on these structures and the natural history of any traumas sustained are, therefore, of key importance. Unfortunately, the literature on these issues, though vast, is far from complete. While it is evident that pregnancy, per se, imposes changes, primarily through hormonal influences, on colonic, ano-rectal and pelvic floor physiology, the long-term impact of such effects is far from clear. Risk factors for the occurrence of significant, though often occult, anal sphincter injuries during birth have been identified and the role of these tears in the etiology of post-partum incontinence has been well delineated. In contrast, the contribution of such intra-partum events to the later onset of incontinence is far from clear and may well have been over-estimated.

Biofeedback Is Superior to Laxatives for Normal Transit Constipation Due to Pelvic Floor Dyssynergia

Uncontrolled trials suggest biofeedback is an effective treatment for pelvic floor dyssynergia (PFD), a type of constipation defined by paradoxical contraction, or inability to relax, pelvic floor muscles during defecation. The aim was to compare biofeedback to laxatives plus education. Patients with chronic, severe PFD were first treated with 20 g/day fiber plus enemas or suppositories up to twice weekly. Nonresponders were randomized to either 5 weekly biofeedback sessions (n = 54) or polyethylene glycol 14.6-29.2 g/day plus 5 weekly counseling sessions in preventing constipation (n = 55). Satisfaction with treatment, symptoms of constipation, and pelvic floor physiology were assessed 6 and 12 months later. The biofeedback group was also assessed at 24 months. Laxative-treated patients were instructed to increase the dose of polyethylene glycol from 14.6 to 29.2 g/day after 6 months. At 6 months, major improvement was reported by 43 of 54 (80%) biofeedback patients vs 12 of 55 (22%) laxative-treated patients (P < .001). Biofeedback's benefits were sustained at 12 and 24 months. Biofeedback also produced greater reductions in straining, sensations of incomplete evacuation and anorectal blockage, use of enemas and suppositories, and abdominal pain (all P < .01). Stool frequency increased in both groups. All biofeedback-treated patients reporting major improvement were able to relax the pelvic floor and defecate a 50-mL balloon at 6 and 12 months. Five biofeedback sessions are more effective than continuous polyethylene glycol for treating PFD, and benefits last at least 2 years. Biofeedback should become the treatment of choice for this common and easily diagnosed type of constipation.

Pelvic floor physiology in women with faecal incontinence and urinary symptoms.

Anorectal manometry, balloon proctometrography, measurement of anorectal angles and videourodynamics were used to investigate 45 asymptomatic women and 13 with faecal incontinence and urinary symptoms, nine of whom also had stress urinary incontinence. The anorectal angle was measured and videourodynamics performed on 17 constipated women with urinary symptoms. Mean (s.e.m.) values obtained with anorectal manometry were lower in women with faecal incontinence and urinary symptoms than in controls (maximum resting pressure 42.5(8.1) versus 82.5(9.3) cmH2O, P = 0.001; maximum attained pressure 80.5(13.7) versus 216.2(11.2) cmH2O, P = 0.001; maximum squeeze increment 35.3(7.5) versus 141.6(10.0) cmH2O, P = 0.001), indicating a weakened puborectalis and external anal sphincter. Mean(s.e.m.) anorectal angles at rest, squeeze and strain were all significantly greater in the doubly incontinent women than in those with constipation (114(3.8) versus 93(5.9) degrees, P = 0.01; 103(2.5) versus 78(3.5) degrees, P < 0.001; 120(2.9) versus 104(4.2) degrees, P = 0.01). Urinary incontinence was worse in the doubly incontinent than in the constipated women (eight of nine versus one of eight with grade 2a or higher, P = 0.002). These results suggest that doubly incontinent women have a significantly weakened pelvic floor and that this should be taken into account before any planned surgery for urinary incontinence.

NORMAL PELVIC FLOOR PHYSIOLOGY

This article outlines the normal physiology of the female pelvic floor, including normal urinary storage and voiding, normal colorectal storage, and defecation. Physiologic changes during a woman's lifetime that may affect bladder and bowel function are also considered. An important framework for understanding the normal physiology of the female pelvic floor is provided, so the reader may gain a more thoughtful approach to the recognition and treatment of pelvic floor pathophysiology.

Magnetic resonance imaging of the lower urinary tract

Magnetic resonance imaging with its excellent contrast resolution and direct multiplanar imaging capacity, has become a valuable tool to improve understanding of lower urinary tract function and pelvic floor physiology. Review of the current English language literature shows that the domain of magnetic resonance imaging is research. In comparison with other imaging techniques, magnetic resonance imaging has been shown to yield better soft tissue differentiation and anatomic resolution. Newer techniques also allow some form of dynamic imaging.

The effects of parturition on female pelvic floor anatomy and function

Our knowledge of the immediate effects of parturition on pelvic floor anatomy and physiology has been sparse. However, with the introduction of computed tomography, ultrasonography, and magnetic resonance imaging, new tools have become available for visualizing dynamic antenatal and postpartum changes in the pelvic musculature. Although few studies have been performed, there is evidence of a pregnancy-related increase in the frequency of urinary stress incontinence, and of an increased frequency of persistent anal incontinence in cases of sphincter tears.

A regional audit of the investigation and treatment of colorectal and pelvic floor disorders (1984?1991)

The activities of a regional physiology unit established for the investigation of colorectal and pelvic floor physiology in health and disease in a clinically relevant setting has been audited and its evolution described over a period of eight years. Trends in surgical treatment of some of these disorders over the same period have also been documented in the Lothian Region. Although there has been little change in the number of patients investigated annually patterns of investigation appear to change. Sphincter manometry, proctometrography and somatosensory reflex measurements have remained the most frequently performed and useful investigations. Spinal stimulation studies increased transiently because of a collaborative investigation of bowel and bladder function in patients with spinal injuries. A considerable increase in surface EMG tests and dynamic proctography has occurred. These trends are thought to be related to interest in defining evacuation dysfunction of the rectum and related problems of the pelvic floor. Isotope proctography now rivals barium videoproctography; at the same time the use of manometric colonic motility studies has diminished. Anal ultrasonography has replaced sphincter mapping in the last year and is being applied to other aspects of anorectal pathology. The last 4 years have seen the introduction and increasing use of non-surgical therapeutic modalities for the treatment of faecal incontinence and constipation: reflex electronic sphincter stimulation, biofeedback and the use of a prokinetic agent to promote colonic motility. Concomitant changes in the surgery of constipation and reconstructive anorectal procedures have been observed. It is recommended that coloproctology units should have easy access to at least one such investigation laboratory within their catchment area together with appropriate auditing facilities.

Physiologic evaluation of the anorectum

Pelvic floor physiology is a complex area of clinical study. Continence and voiding functions are not completely understood. Incontinence is an especially underrated problem. With the use of manometry and ultrasound, anorectal physiology is evaluated and correlated with clinical dysfunction. A description of a previously undescribed ultrasound technique to evaluate anorectal angles and puborectalis function is presented. The results in 10 controls and 53 symptomatic patients with different degrees of continence dysfunction are discussed. The controls showed anal pressures and anorectal angles of 29 cm H2O and 114 degrees at rest and 67 cm H2O and 95 degrees with contraction. Six of the symptomatic patients had complete incontinence to solid stools. The results of their pressures and angles were 14 cm H2O and 151 degrees at rest and 32 cm H2O and 124 degrees with contraction. The values of this group compared with controls is significantly different (P less than 0.05). Ultrasound is helpful in assessing the pelvic floor, both subjectively and objectively. It has the advantages of avoiding radiation and allowing a longer viewing time. It is less expensive compared with radiographic proctography and the data are complementary. Ultrasound and manometry may be useful for long-term follow-up of anorectal physiology.

Pelvic Floor Physiology

Pelvic floor physiology is poorly understood. The funnel shape of the pelvic floor and anal canal is uniquely developed to provide discriminatory continence of gas, liquid, and solid. Proximally, the pelvic floor consists of the pubococcygeus and iliococcygeus muscles. Distally, the anal canal is surrounded by the internal and external sphincter muscles. The anorectal ring is situated between the proximal pelvic floor and the distal anal canal. It is the site of the puborectalis muscle, which is anatomically, neurologically, and functionally merged with the deep portion of the external sphincter muscle. It is at this site that unique forces act to create both a flutter valve and the anorectal angle with the flap valve. Extrinsic pressures at this level reinforce both the flap valve and the flutter valve. Intrinsic pressures are generated by all of the surrounding muscles to produce a high-pressure zone. These factors are critical, but many other factors, such as rectal capacity, compliance, colonic transit, motility, and sensory mechanisms, also interact in a complex way to provide normal continence and defecation. Not surprisingly, no single test allows a complete assessment of the interactions of all these factors. Nevertheless, analysis of components thought to be important in pelvic floor physiology has contributed significantly to the understanding of normal as well as abnormal physiology. Although clinical evaluation continues to be the cornerstone of the diagnosis of pelvic floor disorders, anorectal physiological testing has contributed significantly to our understanding of the dynamics of the pelvic floor. With the refinement of existing techniques and the addition of new investigative tools, it is anticipated that knowledge of pelvic floor physiology will continue to grow.

Maintenance of anal continence: a review of pelvic floor physiology.

Maintenance of anal continence: a review of pelvic floor physiology.