Interstitial cystitis/bladder pain syndrome: when part of the posterior fornix syndrome is potentially curable surgically.

Interstitial cystitis/bladder pain syndrome (IC/BPS) is defined as chronic pelvic pain plus a bladder symptom, usually urge. Evidence is offered to show IC/BPS forms part of the posterior fornix syndrome (PFS), which was defined in 1993 as: chronic pelvic pain (CPP), urge, frequency, nocturia, abnormal emptying, post-void residual urine, caused by uterosacral ligament (USL) laxity and cured or improved by USL repair. The IC/BPS definition implies that the urge and pain of IC/BPS is from a single (as yet unknown) pathogenic origin. However, when urge and pain are viewed from the perspective of the PFS, though both have the same lax USL origin, the anatomical pathway from lax USL to symptom manifestation is very different manifestation. For CPP the anatomical pathway is the inability of loose USLs to support pelvic visceral plexuses (VPs); it is hypothesized that inability of weak USLs to mechanically supports VPs, the afferent nerve synapse from end organs may fire off autologous afferent impulses to the brain which interprets them as pain from end organs such as urothelium, vulva, lower abdomen. For urge, the anatomical pathway is very different: lax USLs weaken the directional pelvic muscle forces which stretch the vagina to support the urothelial stretch receptors. The receptors fire off afferent impulses to the cortex at a lower bladder volume, and these are interpreted as "urge to go". Mechanical support of USLs relieves both pain and urge, as does USL repair.