Whether these musculoskeletal abnormalities of the abdominal wall and pelvic floor musculature found in IC/PBS sufferers represent primary or secondary phenomena remains unknown. It is possible that pelvic visceral pain leads to chronic contraction of regional skeletal musculature, leading to overuse injury and pain. It is also possible that primary pelvic myofascial problems lead to painful and weakened pelvic floor musculature, which also functions poorly to inhibit the urgency associated with bladder filling.