Combined Tibial Nerve Stimulation and Standing for People With SCI

The goal of this clinical trial is to understand how sensory inputs from the lower leg can influence pelvic floor muscle function and urogential function in adults with chronic spinal cord injury (SCI). The main questions it aims to answer are: 1. What is the modulatory role of load and posture on reflex activation of the pelvic floor muscles in participants with SCI? 2. What is the feasibility of combining tibial neuromodulation with standing therapy in participants with SCI? 3. What are the potential effects of combined tibial neuromodulation and standing therapy on reflex excitability and urogential symptoms and quality of life in people with SCI? Participants will be asked complete a series of assessments (questionnaires, electrophysiological testing) before and after a 12-week intervention of combined standing and tibial nerve stimulation therapy.