Morphofunctional Characteristics of The Urinary Bladder at Different Stages of Spinal Cord Injury: A Literature Review

Abstract

Background. Surgical Neurogenic lower urinary tract dysfunction is one of the most frequent and clinically consequential complications of spinal cord injury (SCI), affecting the great majority of patients and constituting a leading cause of morbidity, repeated hospitalisation and, historically, mortality. The urinary bladder does not respond to SCI in a static manner; rather, it undergoes a dynamic, time-dependent sequence of neurogenic remodelling whose morphological and functional characteristics differ markedly between the acute, subacute and chronic phases of injury. Objective. To synthesise the current evidence on the stage-dependent morphofunctional characteristics of the urinary bladder after SCI, integrating neurophysiological, urodynamic, histological and molecular data, and to define the structural correlates of the principal clinical phenotypes. Methods. A narrative literature review was conducted in PubMed, Scopus and Web of Science for articles published predominantly within the last decade (2015–2025), complemented by seminal earlier studies. Fifty-four sources describing human cohorts and experimental (rodent, minipig) SCI models were analysed and organised by injury stage, lesion level, and level of biological organisation. Results. The evidence describes a reproducible trajectory: an acute areflexic, urine-retaining bladder during spinal shock; a subacute emergence of neurogenic detrusor overactivity (NDO) and detrusor–sphincter dyssynergia (DSD) driven by nerve growth factor–dependent C-fibre afferent sprouting; and a chronic phase dominated by detrusor hypertrophy, extracellular-matrix accumulation, a collagen type III→I shift, elastin loss and fibrosis. Quantitative data document early rapid increases in bladder mass, a biphasic course of wall compliance, an approximately 75% increase in wall thickness in chronic models, and consistent remodelling of afferent neurons. The most dangerous phenotype is the chronic suprasacral high-pressure, low-compliance bladder with DSD, which threatens the upper urinary tract, whereas sacral/infrasacral lesions more often yield an acontractile retention bladder. Conclusion. The neurogenic bladder after SCI is best understood as a staged morphofunctional continuum. Structural findings must be interpreted together with urodynamics, because wall thickening alone does not indicate preserved function. Recognising the stage- and level-specific structural correlates is essential for timely, upper-tract-protective management and for the design of morphofunctional research.