Related Experiment Video
Updated: Feb 26, 2026

Detrusor Underactivity Model in Rats by Conus Medullaris Transection
Published on: August 28, 2020
Pathophysiology of the Underactive Bladder: Evolving New Concepts
1UConn Center on Aging, UConn Institute of Brain and Cognitive Science, University of Connecticut School of Medicine, Farmington, CT, USA.
Purpose Of Review:
Underactive Bladder (UAB) is an emerging concept of voiding dysfunction, building on a tradition of often overlapping and confusing terminologies describing the patient experience, urodynamic function, and pathophysiology. This confusion of symptoms with function with pathology has hampered development of an effective disease model.
Recent Findings:
As with other urinary symptoms, the relationship of voiding symptoms to urodynamic dysfunction is variable. Efforts are underway to formally define UAB as a collection of symptoms related to voiding. Defined as voiding symptoms, UAB cannot be reliably linked to detrusor underactivity (DU) nor to detrusor weakness.
Summary:
Progress will be made by characterizing the functional disorders underlying UAB symptoms, examining the biology of these linkages, re-conceptualizing urinary control as one part of a more global biologic adaptive physiology, and determining the relationships of central and peripheral pathologies leading to disrupted control mechanisms.
Related Concept Videos
The Micturition Reflex
The process begins with bladder filling, where the bladder wall stretches as urine accumulates. This stretching activates the urine storage reflex, mediated by the sacral spinal segments and the pontine storage center. Efferent sympathetic impulses stimulate the detrusor muscle to relax and the internal urethral sphincter to contract, facilitating...
Physiology of Urine Formation
Glomerular Filtration
The first stage in urine formation is glomerular filtration. Each kidney contains approximately 1 million nephrons, the functional units of filtration, with a...
Urinary Tract Infection II: Pathophysiology
Physiology of the Genitourinary System III: Urine Concentration and Dilution
Urinary Bladder
In males, the bladder is situated in front of the rectum, while in females, it is positioned anterior to the vagina and uterus. The bladder floor contains an inverted triangular area called the trigone, defined by the two ureteric...
Urinary Tract Calculi II: Pathophysiology and Clinical Manifestations

