{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,17]],"date-time":"2026-07-17T05:05:39Z","timestamp":1784264739063,"version":"3.55.0"},"reference-count":37,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T00:00:00Z","timestamp":1784073600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"NIH","award":["R01NS131489"],"award-info":[{"award-number":["R01NS131489"]}]},{"name":"NIH","award":["R01NS111776"],"award-info":[{"award-number":["R01NS111776"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Closed-loop neuromodulation systems for spinal cord injury (SCI) comprise a sensor layer that detects motor state or intent, a controller that converts this information into stimulation commands, and a stimulation interface that modulates spinal, peripheral, or supraspinal circuits. Although neuromodulation has shown potential for improving stepping, standing, trunk control, and upper-limb function after SCI, the performance of closed-loop systems depends critically on their reliability, latency, and practicality. This structured narrative review focuses on the sensor inputs used in closed-loop neuromodulation for SCI, including kinematic sensors, electromyography, force and pressure sensors, vision-based sensing, and emerging neural interfaces. We summarize how these signals have been used to estimate gait phase, posture, motor intent, and task state, and how sensor-driven strategies have progressed from animal models to early clinical applications. Preclinical studies provide mechanistic insights into activity-dependent, phase-specific, and proprioceptive feedback-mediated control, whereas human studies suggest that sensor-guided stimulation may improve functional specificity; however, comparative evidence remains limited. Future translation will require robust multimodal sensing, standardized reporting of latency and calibration burden, and practical designs suitable for supervised clinical and, ultimately, home use.<\/jats:p>","DOI":"10.3390\/s26144480","type":"journal-article","created":{"date-parts":[[2026,7,15]],"date-time":"2026-07-15T05:39:38Z","timestamp":1784093978000},"page":"4480","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Sensor Inputs and Closed-Loop Neuromodulation in Spinal Cord Injury: From Animal Models to Clinical Translation"],"prefix":"10.3390","volume":"26","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-7912-3362","authenticated-orcid":false,"given":"Erika","family":"Rosado","sequence":"first","affiliation":[{"name":"Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, KY 40202, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9474-0744","authenticated-orcid":false,"given":"Ahnsei","family":"Shon","sequence":"additional","affiliation":[{"name":"Department of Neurological Surgery, University of Louisville School of Medicine, Louisville, KY 40202, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-4056-8923","authenticated-orcid":false,"given":"Wei","family":"Wu","sequence":"additional","affiliation":[{"name":"Department of Anatomical Sciences and Neurobiology, University of Louisville School of Medicine, Louisville, KY 40202, USA"},{"name":"Department of Neurological Surgery, University of Louisville School of Medicine, Louisville, KY 40202, USA"},{"name":"Kentucky Spinal Cord Injury Research Center, University of Louisville, Louisville, KY 40202, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,7,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1938","DOI":"10.1016\/S0140-6736(11)60547-3","article-title":"Effect of epidural stimulation of the lumbosacral spinal cord on voluntary movement, standing, and assisted stepping after motor complete paraplegia: A case study","volume":"377","author":"Harkema","year":"2011","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1394","DOI":"10.1093\/brain\/awu038","article-title":"Altering spinal cord excitability enables voluntary movements after chronic complete paralysis in humans","volume":"137","author":"Angeli","year":"2014","journal-title":"Brain"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"262","DOI":"10.1111\/cns.12530","article-title":"Spinal Cord Stimulation and Augmentative Control Strategies for Leg Movement after Spinal Paralysis in Humans","volume":"22","author":"Minassian","year":"2016","journal-title":"CNS Neurosci. 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