Introduction

To the Editor: The landscape of physical medicine and rehabilitation is rapidly evolving, driven by the urgent need for novel therapies that address the complex challenges faced by people living with disability. Among the most promising advances is neuromodulation, which uses electrical and other forms of stimulation to alter nervous system function through targeted delivery of a stimulus, with the potential to restore health, independence, and quality of life. In this special issue of the American Journal of Physical Medicine and Rehabilitation, we are proud to present a collection of original research articles, case series, and translational studies that exemplify the state of the art in neuromodulation for disabling conditions. The manuscripts included here reflect the diversity, creativity, and rigor of ongoing efforts to advance the field and meet the needs of those who are living with disabilities. Several manuscripts in this issue address the persistent challenges of spinal cord injury (SCI), including autonomic dysfunction, impaired motor control, and chronic pain. Kim et al. present a compelling case series on the effects of high-frequency (600 Hz) sacral root stimulation for improving lower urinary tract and bowel function in individuals with SCI. Their findings suggest that innovative stimulation paradigms may reduce urethral sphincter activity and promote more efficient bladder emptying, without the need for invasive rhizotomy procedures. Lombardo et al. report on the unintended benefits related to reduced hypotension observed in an individual using implanted peripheral nerve stimulation for trunk stabilization after SCI, demonstrating how neuroprosthetic approaches can address critical autonomic issues that impede daily activities and health. Finally, Morrison et al. report advancements in implanted neuromuscular stimulation systems in maintaining seated posture in those with trunk paralysis by automatically adapting to changes in position. These real-world observations highlight the expanding role of neuromodulation in addressing systemic health challenges beyond motor impairment. Pain, long been treated with neuromodulation, remains a major barrier to rehabilitation and participation for many with chronic neurological conditions. This issue features 2 case series from Van Acker et al. that demonstrate how the field is innovating to improve effectiveness and expand the range of treated conditions. One feature is a comparison of ventral column to dorsal column spinal cord stimulation for refractory back and leg pain, suggesting that targeting alternative anatomic structures may offer improved pain relief for individuals who do not respond to conventional approaches. Another demonstrates the potential for peripheral nerve stimulation (PNS) in reducing chronic postsurgical pain after knee arthroplasty. Pierson et al. share the results of a multisite, sham-controlled, randomized controlled trial of peripheral nerve stimulation plus physical therapy for chronic pain due to subacromial pain syndrome, and Aman et al. share results of peripheral nerve stimulation in chronic shoulder pain from a multicenter retrospective review. Finally, a number of articles feature neuromodulatory treatments to improve recovery after a disabling injury or illness. Malley et al. report on their research that expands the scope of vagus nerve stimulation (VNS) paired with task-specific training in the home setting for stroke and SCI that demonstrates the feasibility and impact of extending neuromodulatory therapy beyond the clinic. Xin Li et al. present results of a randomized controlled trial of novel delivery of noninvasive cortical stimulation in upper limb recovery after stroke. Suzhou Li et al. report on spinal reflex modulation by a sensory neuroprosthesis in those with lower limb loss. Finally, Campbell et al. provide a review of cerebellar stimulation to improve recovery after stroke. This special issue serves as a testament to the transformative potential of neuromodulation in physical medicine and rehabilitation. The manuscripts included represent pioneering work across a range of conditions and approaches, from restoring autonomic and motor function to alleviating pain and enhancing independence. We hope these contributions will inspire further research, interdisciplinary collaboration, and ongoing dialogue with those with lived experience of disability. Richard D. Wilson, MD, MSJohn Chae, MD, MS The MetroHealth Rehabilitation Institute MetroHealth System Case Western Reserve University School of Medicine Cleveland Ohio