The Biomechanics of pelvic organ prolapse (POP) surgery The following are core aspects of the Integral Theory (1). The ligaments attach the organs, vagina, ...
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TITLE PAGE The Tissue Fixation System for POP, chronic pelvic pain, bladder and bowel dysfunction. 1,2
Peter Petros* DSc PhD DS MB BS MD FRCOG FRANZCOG CU
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University of NSW , Professorial Surgery Department, St Vincent's Clinical School, Sydney, NSW, Australia 2
Dept. of Mechanical and Chemical Engineering, University of Western Australia.
NOTE To facilitate reading and understanding, references have been kept to an absolute minimum. Comprehensive references are available in the 3rd edition of the textbook, ‘The Female Pelvic Floor” 3rd Ed Petros, Springer 2010. SUMMARY The TFS surgical system is based entirely on the Integral Theory, which states Pelvic organ prolapse, bladder and bowel dysfunction and some types of pelvic pain, mainly derive, for different reasons, from laxity in the vagina or its supporting ligaments, a result of altered collagen/elastin. The aim of this chapter is to explain how just 5 loose pelvic ligaments may cause pelvic organ prolapse ‘POP’, chronic pelvic pain, bladder and bowel dysfunction, and how these dysfunctions may be repaired by shortening and reinforcing these ligaments. These questions arise 1. How can loose ligaments cause prolapse of the bladder, uterus and rectum? 2. How can loose ligaments cause such a wide variety of symptoms? Question 1 is answered in Part 1. Question 2 is answered in Part 2
PART 1 - PELVIC ORGAN PROLAPSE Part 1 comprises biomechanics, surgical anatomy, TFS surgery.
The Biomechanics of pelvic organ prolapse (POP) surgery The following are core aspects of the Integral Theory (1). The ligaments attach the organs, vagina, bladder, rectum to the skeleton from above, fig 1. The pelvic muscles stretch them from below, fig2. As they provide the strength for the suspension, the ligaments are strong and inelastic. Because the organs and the vagina need to expand and contract, they contain significant quantities of elastin, but have far less have less structural strength. Estimated breaking strain of ligaments is approximately 300 mg/mm2 and vagina approximately 60 mg/mm2 , Yamada 1970 (2). Collagen I provides structural strength and elastin stretchability. Both weaken with age, especially after the menopause. Elasticity of the vagina is fundamental to its function during organ closure, evacuation, intercourse and is a low energy mechanism for closure of the urethra. From these simple biomechanics, two surgical principles follow which need to be observed during
2 pelvic reconstruction. 1. It is the ligaments which provide suspensory strength, so they must be reinforced in any surgical reconstruction, preferably with a precisely placed tape along the length of the ligament. 2. The vagina functions as an elastic organ. Its elasticity must be preserved. Vaginal excision will only reduce the quantum of collagen and elastin available for normal vaginal function.
Surgical anatomy of POP The ligaments The organs are suspended to the pelvic side wall skeleton by 5 main ligaments uterosacral (USL) cardinal (CL) arcus tendineus fascia pelvis (ATFP) pubourethral (PUL) and perineal body (PB), figs 1-6. The perineal bodies are suspended from the descending ramus by the deep transversus perinei muscle ‘DTP’, fig 2. ‘Muscle’ is a misnomer for DTP. Its structure is similar to the other ligaments, with only small amounts of striated muscle. The ligaments and the structural layer of vagina known as pubocervical (PCF) and rectovaginal (RVF) fascia are composed of collagen, elastin, smooth muscle, blood vessels and nerves, so they are contractile.
Fig 1 Five main ligaments attach organs to the skeleton The TFS has been inserted into each ligament Uterosacral (USL) attaches to sacrum, rectal walls laterally and cervix anteriorly. ATFP attaches to the pubic symphysis just above PUL, the paracolpium of the lateral vaginal walls and ischial spines Cardinal attaches to anterior cervical ring, the pubocervical fascial layer of anterior vaginal as it attaches to the cervical ring, lateral cervix, USL and lateral side wall of the skeleton Pubourethral (PUL) attaches to midurethra, anterior portion of m.pubococcygeus (m.pubovaginalis) and lower border of the pubic symphysis Perineal body (PB) attaches to distal rectum &vagina and to the descending ramus via the deep transversus perinei ligaments. External urethral ligament (EUL) attaches the external meatus to the anterior surface of the pubic bones. It is a 6th ligament which is important for urethral sealing. Published by permission, TFS surgical.
Fig2 Attachment of perineal bodies (PB) behind descending ramus. The PBs have been separated during childbirth, causing stretching of the central tendon (not shown) allowing the rectum to protrude into the vagina as a rectocele.
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Fig 3 The interaction of ligaments and muscles. The uterosacral (USL) cardinal (CL) arcus tendineus fascia pelvis (ATFP) pubourethral (PUL) ligaments suspend the vagina and organs from above; bidirectional muscle forces (arrows, M) contract against the ligaments to tension the vagina and the organs. The muscle forces (arrows) contract selectively to open and close the urethra and anus during evacuation and closure.
The vagina is a weak elastic membrane which is attached to the cervix and side wall skeleton via its ligamentous and muscular attachments. Clarification The vagina has a squamous epithelial layer and attached below, a ‘fascial’ layer, PCF (pubocervical fascia) for the anterior vaginal wall and ‘RVF’ (rectovaginal fascia) for the posterior vaginal wall. Both structures contain smooth muscle, collagen, elastin, nerves and blood vessels. Anterior vaginal wall The fascial layer (pubocervical fascia ‘PCF’) attaches to the anterior cervical ring and cardinal ligaments, laterally to ATFP and distally to pubococcygeus muscle (‘pubovaginalis’) distal urethra and external urethral ligament, fig 4.
Fig4 Anterior vaginal attachments to skeleton. The vagina is suspended like a trampoline membrane between the Arcus Tendineus Fascia Pelvis (ATFP) ligaments laterally, the anterior part of the cervical ring, cardinal ligament (CL) and distally to the lower half of urethra (U)via the pubourethral ligament which inserts into the urethra.
Posterior vaginal wall The fascial layer (rectovaginal fascia ‘RVF’) attaches to uterosacral ligaments, posterior cervical ring, ATFP laterally via the paracolpium, perineal body and rectum distally, fig 5. Consequential anatomical relationship of uterosacral ligaments with the rectum, fig5. The USL attaches to the lateral walls of rectum and suspends it to the skeleton (sacrum); m.levator plate (LP) inserts into the posterior rectal wall.
4 Rectovaginal fascia ‘RVF’ attaches to levator plate ‘LP’, perineal body ‘PB’ and cervix. LP contracts backwards to tension the uterus, USLs, perineal body and posterior wall of the rectum. Anything which loosens USL will create a cascade of symptoms from the functions dependent on the muscle/ligament relationships. These are summarized in the algorithm,fig10. Organ spaces are essential to allow free movement of bladder over vagina and vagina over rectum. Especially vulnerable is the rectovaginal space. If rectum and vagina are glued together via a mesh or surgical scarring, this may prevent natural stretching during intercourse in some individuals and dyspareunia may result. The basic cause of the pain is the stretching of the viscerally innervated vagina; pain in a visceral organ is caused by distension.
Fig5 The uterosacral ligaments (USL) attach uterus to sacrum, to the lateral rectal walls, cervical ring (CX), cardinal ligament (CL), fascial layer of posterior vaginal wall (rectovaginal fascia ‘RVF’) and perineal body (PB) in its distal 50%. Note the organ space between posterior vaginal wall and rectum. It needs to be preserved to allow indepenedent movement of vagina over rectum during intercourse.
The muscles. There are 4 directional pelvic muscles, two forward acting, m.pubococcygeus (PCM), m.puborectalis (PRM) and two backward, m. levator plate (LP); conjoint longitudinal muscle of the anus (LMA), fig6. They support the organs from below. They contract or relax selectively to close the urethral or anal tubes (continence), open them (evacuation) or support the bladder and rectal stretch receptors to control the micturition and defecation reflexes.
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Fig 6 The principal muscles and ligaments of the pelvic floor. Forward contracting m.pubococcygeus (PCM) ; m.puborectalis (PRM). Backward contracting m. levator plate (LP); conjoint longitudinal muscle (LMA). Ligament labelling as in fig2. LP inserts into the posterior wall of rectum; LMA connects LP to the external anal sphincter and contracts downwards.
Muscles contract against suspensory ligaments, fig 6 With reference to fig 6, only the PRM does not contract against any ligaments. It contracts against the pubic symphysis; the pubovaginalis portion of PCM contracts forwards against the pubourethral ligament (PUL); LP contracts backwards against PUL; LP and LMA contract backwards and downwards against the cardinal/uterosacral ligament complex (CL/USL). If a ligament is loose, the muscle lengthens and loses contractile force, Gordon’s Law (3). All functions of that muscle will be compromised, as a striated muscle must have a firm insertion point to function optimally. Pathogenesis of POP Causation of pelvic organ prolapse is by stretching of the suspensory ligaments, and/or distension or tearing of vaginal fascia, figs 7,8.
Fig. 7. Ligament damage at childbirth. View from above at 10cm dilatation of the cervix. The maximal strain of the 10cm dilatation is on the cervical ring attachments of vaginal ‘fascia’, uterosacral ligaments (USL) and cardina1(CL) ligaments. Extension or tearing of these attachments may cause apical prolapse, cystocele anteriorly, rectocele and enterocele posteriorly. The perineal body may be damaged and separated to cause low rectocele (perineocele) as the head exits the birth canal.
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Fig 8 Ligament damage at childbirth, schematic sagittal view Fig 8 As the head descends down the birth canal, circles 1-4, it may stretch or tear the ligaments or fascial attachments of the vagina. Circle 2. Cystocele. Defects: ATFP, CL anterior vaginal wall Circle 3. Uterine prolapse, high rectocele, enterocele, anterior rectal wall intussusception Defects: USL, posterior vaginal wall. Circle 4 Middle and low rectocele Defects:PB, posterior vaginal wall defects. Circle1 Stress urinary incontinence Defects: PUL, EUL, distal vagina defects.
TFS SURGERY FOR POP AND PELVIC SYMPTOMS The same surgical methods apply for major prolapse or major symptoms with minimal prolapse. Basic surgical principles 1. Ligaments must be shortened and reinforced, preferably with a precisely located tape. This is sufficient to restore all prolapses, apical, cystocele, rectocele and to restore the contractile force of the pelvic muscles which control bladder and bowel function. 2. The uterus and vagina are conserved*. *Excision of vagina will shorten or narrow it and decrease its quantum of elasticity. The uterus functions like the keystone of an arch, fig 9. All the suspensory ligaments directly or indirectly connect to the uterus. The effect of hysterectomy on structure and function becomes evident as collagen atrophies with age, especially after the menopause.
Fig 9 Preservation of uterus is important. The uterus functions like the keystone of an arch. Hysterectomy weakens the ligamentous insertions and predisposes to collapse of the vaginal walls as the patient ages.
7 Which ligament to repair? The surgery is guided by the diagnostic algorithm, fig 10.
Fig 10 Diagnostic algorithm (structural version) Symptoms indicate which ligaments cause a particular prolapse and which symptoms are associated with damage in particular ligaments.
The TFS tools The TFS consists of an applicator, (AP) a non-stretch tape (T) attached to two soft tissue anchors (A) with a one-way adjustable mechanism for the tape which passes through the base. The tape is 7.5mm wide. It is a lightweight, non-stretch type I lightweight macropore monofilament polypropylene mesh tape. At the base of the anchor is a system which allows one-way directional tensioning of the tape. On tightening the tape, it shortens and reinforces damaged ligaments.
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Fig 11 The TFS tool for creation of artificial collagenous neoligaments. The TFS consists of an applicator, (AP) a non-stretch tape (T) attached to two soft tissue anchors (A) with a one-way adjustable mechanism for the tape which passes through the base. Published by permission TFS Surgical.
The TFS surgical technique Exactly the same surgical technique is used to repair all 5 ligaments, PUL, ATFP, CL, USL, PB. The TFS sling is applied in up to 5 sites, fig 2, depending on which ligaments are deemed to be damaged. The tape is applied into the body of the ligament, or directly adjacent to it. The tape creates a collagenous tissue reaction which strengthens the natural ligament. Operation The vagina is incised. Bladder, rectum enterocele are dissected off the ligaments as required. The ligament is identified. A tunnel is made through the ligament with Metzenbaum scissors. The applicator is inserted into the tunnel to the required length. The anchor is released. The operation is repeated on the contralateral side and the tape is adjusted until tape looseness is removed and a resistance is felt. This indicates return of muscle tone in the muscles which act on that ligament. The tape is cut and the vagina is closed. How the TFS works The TFS shortens and strengthens all 5 ligament structures, fig 12. The TFS has minimal contact with the vaginal wall as it is applied transversely. Unlike large mesh sheets applied to the vaginal wall, the tapes do not inhibit the forward and backward movements of the muscle forces which are essential for opening, closure and tensioning of the bladder and rectum.
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Fig 12 TFS repair of 5 supporting ligaments - standing view. The tapes attach the organs transversely to the skeleton. The anterior vaginal wall is supported by ATFP and CL. The uterus is held up like the apex of a tent by USL and CL. The posterior vaginal wall is supported by USL cranially and PB distally.
Fig 13 The anatomical position of the 5 TFS tapes. 3D Panoramic view into the pelvis from above. Standing position. The anchors and tapes penetrate, shorten and strengthen the loose ligaments by creation of an artificial collagenous neoligament: PUL: pubourethral; ATFP: arcus tendineus fascia pelvis (‘USling); CL: cardinal: USL: uterosacral; PB: perineal body. EUL is the external urethral ligament. TFS repair of EUL rarely needs to be repaired. Published by permission TFS Surgical.
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Fig.14. How the TFS binds the organs to hiatus and skeleton. View into the pelvis from above. From above down: TFS USling (ATFP), TFS cardinal ligament, TFS uterosacral ligament. Tensioned tapes create collagenous neoligaments which bind vagina (V), bladder (B), rectum (R) to the hiatal muscles (PVM) en route to the skeleton. The tapes limit the ‘ballooning’ of the hiatus so frequently seen in POP. Arrows indicate the direction of tensioning through the one-way system (blue ovoid circles).
TFS cystocele repair Surgical anatomy and preliminaries Which operation, ATFP or cardinal? Correct diagnosis of which ligaments are damaged is an essential precondition for repair . The major cause of cystocele is dislocation of the anterior vaginal wall (PCF) from the cardinal ligament/anterior cervical ring attachment, ‘3’, figs .15-17. Generally, vaginal rugae are present with such tears. Paravaginal and central defects ‘1’&’2’, fig 15, are related and are almost invariably associated with transverse defect, defect ‘3’; the vaginal skin is generally smooth, figs 18a,18b. Fig 18b emphasizes why vaginal epithelium should not be excised: there is always a musculoelastic layer present even in the thinnest appearing epithelium. Rather than excision, reassignment of any loose epithelium to a deeper ‘fascia’ layer should be made, fig 19.
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Fig. 15 Potential sites of damage:. Schematic 2D view from below. Perspective: looking into the anterior wall of the vagina. 1. Midline defect (central part of PCF) caused by overstretching of vagina. 2. Paravaginal or lateral defect: dislocation or stretching of the collagenous ‘glue’ attachment to ATFP. 3. High cystocoele or transverse defect: dislocation of attachment of vagina to anterior cervical ring and cardinal ligament. Dislocation of the ATFP from the ischial spines (IS) is usually associated with high cystocele; there is an associated shallow sulcus and downward rotation of the proximal vaginal wall on straining.
Fig 16 Dislocated cardinal ligaments 3rd degree cystocoele. The vagina‘V’ prolapses downwards lateral to cervix ‘CX’. The presence of rugae indicates that this is a pure CL dislocation. In patients with prior hysterectomy, the ligaments prolapse lateral to the hysterectomy scar.
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Fig 17. The cardinal ligament (CL) extends anteriorly to fuse with the cervical ring (r) and the pubocervical fascia (PCF) of vagina. A break in CL and PCF attachments to the cervical ring during labour ring may cause the anterior vaginal wall to rotate downwards like a trapdoor to form a ‘high cystocoele’. In this situation, the cardinal ligaments also prolapse downwards lateral to the cervix to form the characteristic prolapse (‘drooping’) of vagina lateral to the cervix or hysterectomy scar seen in fig 16.
Fig 18a 4th degree cystocele. Distension or tearing of Cardinal and ATFP ligament attachments have caused ballooning outwards of the vagina. A smooth epithelium is characteristic. TFS cardinal and ATFP (USling ) operations are indicated. No vaginal excision is required.
Fig 18b Histology of fig 18a. Note that even with apparently thin smooth epithelium, an underlying ‘fascial’ layer (smooth muscle, collagen, elastin, nerves, blood vessels) is always present.
Fig 19. Redundant vagina is not excised. It is sutured into the deeply sited musculofascial layer which can be found laterally.
13 TFS cardinal ligament operation, fig 20. Even with lateral/ central defects, the cardinal ligament is always repaired first. Under tension, a transverse incision is made at the vesicocervical junction, usually 1-1.5 cm above the cervix or hysterectomy scar. If the surgeon prefers it, a longitudinal incision is made, commencing 1cm behind bladder neck, extending to the cervix. Under tension, the bladder is dissected off the cervix or hysterectomy scar taking care to dissect it laterally off the vagina. This is to protect against perforation during the application of the tape. Using a gently curved Mayo scissors, with tips always pressed towards the vaginal mucosa, a channel is made to the side wall. A finger is inserted to further define the channel. The TFS applicator is inserted into the channel until the fascia is perforated at the side wall. The anchor is released, tugged laterally to embed the prongs, then checked to ensure it has gripped. The procedure is repeated on the contralateral side. The tape is now tightened until a resistance is felt, an indication that the muscle strength has returned. TFS ATFP repair, USling operation, fig 20. In the 20% of patients where a bulging persists after CL TFS surgery, the USling operation is performed. Surgical principle The tapes support the vagina in the manner of ceiling joists (TFS) supporting a ceiling plaster board (vagina). Like a ceiling plaster board, a damaged vagina has little structural strength. Operation A separate full thickness vertical incision about 5 cm long is made, beginning 1cm behind the bladder neck. The bladder is dissected off the vagina as per a standard native tissue repair sufficiently to create a channel for the tape. A channel is made with dissecting scissors behind the descending ramus, ascending towards the insertion of ATFP at the pubic bone. The applicator is inserted into the channel, the anchor released and checked for grip. This procedure is repeated on the contralateral side and the tape is tightened until a resistance is felt. The vagina is sutured.
Fig. 20. Cardinal ligament and ATFP TFS operations for cystocele repair. Schematic view into the anterior wall of the vagina. The tapes support the vagina in the manner of ceiling joists supporting a ceiling plaster board . The horizontal tape provides structural support to the proximal half of the anterior vaginal wall, recreates the cervical ring, crosses ATFP near the ischial spine and re-attaches a detached ATFP to the skeleton. The U-sling reinforces the existing ATFP structures proximally. It provide structural support to the distal half of the vagina , supporting the central defect and re-attaches a dislocated PCM to the symphysis.
TFS Uterosacral ligament (USL) operation Surgical anatomy and preliminaries The uterosacral and cardinal ligaments are related. It is evident from fig 21, that with any degree
14 of uterine or apical prolapse, the cardinal ligaments are also elongated, so they should always be repaired at the same time as the USL. In the standing position, the USL is some 3cm higher than the sacrospinous ligament , Fig 22. The TFS Uterosacral ligament (USL) operation is therefore more anatomically accurate than insertion in the sacrospinous ligament and will result in a longer vagina.
Fig. 21. Uterine prolapse is caused by laxity in both CL and USL and their adjoining fascia
Fig 22. Standing position The Uterosacral ligaments (USL) are sited about 3cm higher than the sacrospinous ligaments (SSL).
TFS Surgery for USL repair Under tension, a full thickness transverse incision 5cm wide is made approximately 3-4 cm below the cervix or hysterectomy scar. If the prolapse is 3rd or 4th degree, the incision is made 1-2cm below the cervix, as the tape will need to shorten a longer length of USL. Alternatively a vertical incision can be made. Any enterocele is dissected to allow access to the USLs. The vagina is now stretched and the USLs are located. Look for them at 2 and 10 o’clock. These are grasped with Allis forceps. The direction of the USLs is determined, important for the channel and tape insertion. A small bleb of local anesthetic is injected into the ligament to enlarge it. A vertical incision is made in the superior border of the USL. Still under tension, a fine Metzenbaum scissors is inserted into USL to create a tunnel for the TFS which extends to 1cm short of the sacrum. Rectal examination during this maneouvre is very helpful. Still tensioning the vagina, the applicator is inserted into the USL to within 1cm of sacrum. The procedure is repeated on the contralateral side. The tape is tightened and checked to ensure the anchor has gripped. The vagina is closed.
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Fig 23 TFS CL and USL repair of uterine/apical prolapse The cardinal TFS tape re-attaches the dislocated CLs 2cm above and forward of the ischial spine. This automatically re-attaches an ATFP torn from the ischial spine (IS) to the side wall. The tape reglues the dislocated PCF attachments to the cervical ring.
TFS surgery for perineal body (PB) Preliminaries Surgical anatomy and preliminaries The perineal body functions as a unit with the uterosascral/cardinal ligaments. It is therefore standard practice to repair USLs at the same time as PB repair, especially in cases of descending perineal syndrome, anterior rectal wall intussusception, obstructed defecation or fecal incontinence. There are actually two perineal bodies connected by a central tendon. During childbirth, the tendon is stretched and the two PBs are displaced laterally, allowing protrusion of a rectocele, fig24. The PBs are attached behind the descending ramus exactly at the junction of the upper 2/3 and lower 1/3, fig3, by the deep transversus perinei ‘muscle’(DTP) *. * The DTP is whitish in colour and except for the presence of some striated muscle fibres, it has the classical histological appearance of a ligament, collagen, smooth muscle, elastin, nerves, blood vessels.
The model in figures 25&26 represents TFS repair of the descending perineal syndrome. It shows how the TFS shortens, reinforces, elevates and centrally restores loose, elongated, laterally displaced ligaments, in this instance, perineal bodies. The deep transversus perinei ligaments attach the perineal bodies to the descending ramus. Surgery Under tension, a transverse incision 5cm wide is made just behind the hymen. The vagina is dissected off the rectum and the laterally displaced PBs are identified. The PB is whitish in appearance. On stretching, it is important to confirm that it inserts into the descending ramus*. Using a strong curved needle on a No1 vicryl suture, the PB is ‘dug out”: the needle is placed into the PB and it is lifted up and grasped with a strong forceps. Using Metzenbaum scissors, a tunnel is made into each PB, through the deep transversus perinei muscle (DTP), penetrating its insertion to just behind the descending ramus. The scissors needs to be horizontal. Any downward angulation may injure the pudendal nerve as it exits Alcock’s Canal. The applicator is inserted, the anchor is released, checked and the procedure is repeated on the contralateral side, stopping when a resistance is felt. The incision is closed. * The pubococcygeus is situated close by the DTP. It is a deep red colour. On pulling it can be confirmed that it inserts just behind the inferior border of the pubic bone.
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Fig 24 Diagnosis of laterally separated perineal bodies can only be made by rectal examination. The perineal bodies are separated. The central tendon is thinned out. The rectum protrudes forward on digital pressure.
Fig 25 TFS PB operation for descending perineal syndrome. The laterally displaced perineal bodies (PB) are attached behind the upper 2/3 and lower 1/3 of the descending ramus by the deep transversus perinei ligament. A tunnel ‘is made through PB and the ligament penetrating behind the ramus. The TFS anchor ‘A’ is inserted bilaterally. Note the downward angulation of the PBs.
Fig 26 Tightening of the tape The PBs are elevated as the tape is tensioned. This, reverses the ‘descending perineal syndrome’ anatomy; a 1.5-2cm gap is left between the PBs. This fibroses in time to form a new central ligament.
Results of TFS PB surgery Thirty patients with 3rd degree rectocele, symptoms of obstructive defecation and manually assisted defecation underwent TFS USL and TFS PB surgery. At 12 months follow-up, cure of symptoms of manually assisted defecation and prolapse was achieved in 27 patients (90%) of patients. TFS repair of pubourethral ligaments Surgical anatomy and preliminaries There may not be significant distal vaginal prolapse with PUL laxity. The main symptom is urinary stress incontinence, (USI), but also, urgency when associated with USI and fecal incontinence when associated with USI. A midurethral sling is
17 applied to shorten and reinforce damaged pubourethral ligaments. The technique is retropubic. Like the TVT, the TFS creates a neoligament in the exact position of the pubourethral ligament. TFS Surgery for repair of PUL, fig 27. The first part of the TFS midurethral sling is almost identical to that of the TVT Under tension, a full thickness incision approximately 2cm long is made between midurethra to within 0.5cm of the external meatus. Under tension, pointing towards ipsilateral shoulder, dissecting scissors create a tunnel until a resistance is encountered, the perineal membrane. The scissors is guarded with a forefinger, and a 1.5-2cm perforation is made. The applicator is guarded, inserted, the anchor released and checked for grip. The procedure is repeated on the contralateral side. A No8 Hegar dilator is inserted into the urethra during tightening of the tape to prevent urethral constriction. The tape is then tightened until a resistance is felt. The bladder is filled and cystoscopy performed to ensure there is no perforation of the tape. If urine continues to leak after removal of the cystoscope, it indicates that the tape is too loose. The Hegar is inserted and the tape is tightened. The tape should never be tightened without a Hegar in the urethra. Repair of distal closure mechanism The hammock/external urethral ligament (EUL) are now repaired, as in fig 28. With a Foley No18 catheter in situ, a continuous suture is inserted into the EUL, fascial layer of the vaginal hammock, first on one side, then the other and the suture ends by insertion into the contralateral EUL. The suture is gently tightened. The vaginal epithelium is now closed with interrupted sutures.
Fig. 27. Retropubic repair of PUL. The midurethral tape is anchored into the origin of the pubourethral ligaments, immediately behind the perineal membrane
Fig 28 Repair of distal closure mechanism The vaginal hammock fascia and the external ligamentous attachment of the external urethral meatus were tightened with 2–0 Vicryl sutures
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Fig.29. Rationale for EUL repair- the urethral sealing mechanism. The main function of the distal mechanism (hammock and EUL) is sealing of the urethral mucosa rather than closure during effort. The vagina ‘V’ is pulled forwards towards the bone by the anterior portion of pubococcygeus muscle (arrow) pulling against the external urethral ligament (EUL) and the pubourethral ligament (PUL). Laxity in EUL, PUL or V may invalidate the closure force by the muscle. Symptoms are insensible urine loss, often accompanied by “a feeling of a bubble of air escaping”.
Results -TFS repair of PUL Using a local anesthetic technique, Sekiguchi (6) reported 91% cure of USI including the 40% of patients who had ISD. In a 5 year RCT, Sivaslioglu (7) reported 89% cure for TFS and 78% for TOT. Urinary retention (n=2/40), groin pain (n=12/40) and mesh extrusion (n=1/40) were noted in the TOT group. In the TFS group there was no urinary retention or significant postoperative pain, but anchor displacement (left side) was found in 1 patient. Table 1 Operative details CL/USL surgery 12 month data -1036 tapes in 278 patients, Inoue (4). Variable Value Range Mean operation time (min) 96.2 39-190 Mean estimated blood loss(ml) 75.1 7-280 Hospitalization after operation 0.7 0-7 Same day (38%) Mean days, Return to usual life 2.2 1-30 Mean tape per patient 3.5 1-5 Prolapse cure 92.1% (n=278)
