Discussion
Ligaments for structure, vagina for function The differential biomechanics of ligaments (structure) and vagina (function) endorse the intuition of Fothergill in making CL and USL repair key parts of his operation. Tissue biomechanics explain poor results for prolapse with vaginal repair only [1]. Ligaments 300 mg/mm2[7] are the main structural support of the uterus while the more elastic vagina 60mg/mm2, transmits the muscle forces to close and open the urethra, and to stretch the vagina to control the afferent impulses from the urothelial stretch receptors [8].
Vaginal conservation The vagina is an organ. Once its collagen and elastin are excised, they cannot be regenerated. Rather than excision, excess vaginal tissue can be easily re-assigned, fig7. The cut edge of epithelium is brought down onto the fascia below, in effect, compressing the loose tissue. Within a few weeks the component collagen and glycosaminoglycans which constitute the structural elements of the vagina re-order the tension within the vaginal tissue, so by 6 weeks review, vaginal appearance appears normal. Excision and scarring may fibrose the vagina sufficiently to cause the “Tethered Vagina Syndrome” (TVS) [9], which may cause massive urine loss, characteristically on getting out of bed in the morning. TVS can only be repaired by a skin graft to the vagina.
Minimizing excision of tissues reduces bleeding. By conserving vagina, not hiding potential bleeding points on the cervix behind Sturmdorf sutures, not transecting CL, many potential bleeding points are avoided.
Native ligament repair does not work well after the menopauseShkarupa et al. published native ligament repair data for CL/USL much as described here, in two cohorts, premenopausal and postmenopausal [10]. By 18 months, good results for cure of prolapse, OAB (urge, frequency, nocturia) were obtained at 3,6,12,18 months, Table 1, but only for the premenopausal cohort. A massive stepwise deterioration in symptoms and prolapse occurred by18 months, Table1. The authors concluded that the cause for the rapid deterioration was collagen breakdown in the ligaments [10]. They recommended cardinal/USL slings in postmenopausal women.
Use of No2 polyester . The midurethral sling’s success in curing stress urinary incontinence is based on harnessing the collagenopoietic effect of an implanted polypropylene tape to structurally reinforce weakened pubourethral ligament [11]. The collagen created, collagen I, has a breaking strain of 18,000 lbs / sq inch[11]. It follows, not much collagen is required to reinforce a ligament 0.5-0.7mm in diameter. Our aim in using a thick No2 polyester suture was to create new collagen to reinforce the native tissue ligament repair.
Conclusions The minimally invasive repair faithfully follows the Fothergill principle of ligament repair, suitably modified to conserve tissue, reduce bleeding and hopefully, to provide longer term cure.
Contributions Surgery VIDEOS PP RH XS. Planning PP RH XS Analysing PP RH XS WJL Writing PP RH XS
Conflict of interest NIL for any author.
Ethics Not applicable. These are standard hospital operations for all authors.
Funding NIL