SPARC Bladder Mapping and Training Study

Deficits in urologic function after spinal cord injury impact quality of life and consistently ranks as a top priority issue in the spinal cord injury population. Bladder dysfunction may manifest as detrusor hyperreflexia (bladder contractions at low volumes, causing incontinence and smooth muscle hypertrophy), detrusor-sphincter dyssynergia (uncoordinated bladder and external urethral sphincter contractions, causing inefficient emptying and smooth muscle hypertrophy), decreased compliance (unable to store urine under appropriately low pressures) and loss of continence, requiring lifelong management, maintenance, and health care visits. Current therapeutic approaches aim to manage both the storage and voiding phases of bladder function and include intermittent catheterization, pharmacologic and surgical interventions. While most of these strategies are necessary for urological maintenance post-injury they oftentimes are associated with side effects and therefore remain inadequate. Therapies addressing recovery of function are still needed. The use of spinal cord epidural stimulation is a promising alternative approach to addressing the primary phases of bladder dysfunction. Additionally, the effects of spinal cord epidural stimulation on bladder alone is not known as its use has been directed towards the locomotor system. Thus, the overall objective of this study is to perform functional mapping in order to identify the spinal cord epidural stimulation configurations (anode/cathode selection, amplitude, frequency and pulse width) at the lumbosacral level that can promote neural control of bladder storage (capacity) and bladder emptying (voiding efficiency) after spinal cord injury.

Inclusion criteria

• stable medical condition without cardiopulmonary disease or dysautonomia that would contraindicate bladder training;
• clear indications that the period of spinal shock is concluded determined by presence of muscle tone, deep tendon reflexes or muscle spasms and discharged from standard inpatient rehabilitation;
• non-progressive supra-sacral SCI (i.e., upper motor neuron re bladder circuitry);
• AIS classification A or B;
• at least 2 years post spinal cord injury.

Exclusion criteria

• Painful musculoskeletal dysfunction, unhealed fracture, contracture, pressure sore or urinary tract infection that might interfere with mapping/training;
• Clinically significant depression or ongoing drug abuse;
• Pregnant at the time of enrollment or planning to become pregnant during the time course of the study
• Bladder Botox injections within the past year;
• Continent diversion procedures with or without bladder augmentation.