{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T23:50:42Z","timestamp":1790639442872,"version":"4.1.0"},"reference-count":42,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2026,6,29]],"date-time":"2026-06-29T00:00:00Z","timestamp":1782691200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000065","name":"National Institute of Neurological Disorders and Stroke","doi-asserted-by":"publisher","award":["5U44NS111076"],"award-info":[{"award-number":["5U44NS111076"]}],"id":[{"id":"10.13039\/100000065","id-type":"DOI","asserted-by":"publisher"}]},{"award":["5U44NS111076"],"award-info":[{"award-number":["5U44NS111076"]}],"id":[{"id":"https:\/\/ror.org\/01s5ya894","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: Robotics training improves gait after stroke, but no prior studies have investigated whether emerging long-term gait biomechanics improvements occur after training. We assessed the temporal profile of pre-post gait biomechanics changes after 9 weeks of dorsiflexion specific adaptive control ankle robot (AMBLE\u2122) training, and at 9 weeks post-training and 17 months later in three persons with chronic stroke to probe for ongoing locomotor plasticity versus post-training disuse decay. Materials and Methods: Three densely hemiparetic subjects (mean \u00b1 SD), age 62 \u00b1 7 years., stroke latency 8 \u00b1 4 years, available for repeat testing from an original N = 24 robotics training cohort study, underwent three-dimensional gait analyses pre-post 9 weeks of AMBLE training, and then 9 weeks and 17 months after all robotics training ended. Results: We found that only 47% of total improvements in heel-first strikes and 31% increased paretic step length occurred pre-post training. Unexpectedly, all other biomechanical improvements manifested progressively 17 months after training ended, including ankle peak swing angle (\u2206 = 7\u00b0), dorsiflexion angular velocity (\u2206 = 23\u00b0\/s), peak knee flexion (\u2206 = 11.1\u00b0) and hip flexion (\u2206 = 6\u00b0). Robotics prescription progressions in level of assistance and dorsiflexion target angle strongly correlated to gait biomechanical outcomes at 17 months, including improved heel-first strikes and peak dorsiflexion swing angle in this small sample. Conclusions: These findings show that initial improvements in foot\u2013ankle function across training are followed by emergent biomechanical improvements in ankle, knee and hip kinematics across 17 months post-training, with delayed outcomes related to robotics prescription progression. The temporal profile of biomechanical adaptations might suggest delayed, progressive reduction in pathological multi-joint synergies of the hemiparetic leg. However, findings are exploratory and cannot establish causality, treatment efficacy or broad generalizability. Future research is needed to determine whether ankle robotics training can catalyze improvements in long-term gait biomechanical safety and efficiency in the chronic disease management of stroke.<\/jats:p>","DOI":"10.3390\/medicina62071250","type":"journal-article","created":{"date-parts":[[2026,6,29]],"date-time":"2026-06-29T05:49:33Z","timestamp":1782712173000},"page":"1250","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Ankle Robotics Induces Ongoing Locomotor Plasticity with Delayed, Sustained Multi-Segmental Gait Improvements 17 Months After Training in Chronic Stroke"],"prefix":"10.3390","volume":"62","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2393-1268","authenticated-orcid":false,"given":"Anindo","family":"Roy","sequence":"first","affiliation":[{"name":"NextStep Robotics, Inc., MDC Studios, 300 West Pratt Street, Ste 200, Baltimore, MD 21201, USA"},{"name":"Maryland Robotics Center and Maryland Applied Graduate Engineering (MAGE), University of Maryland, College Park, MD 20742, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3799-5710","authenticated-orcid":false,"given":"Kelly","family":"Westlake","sequence":"additional","affiliation":[{"name":"Department of Physical Therapy and Rehabilitation Science, University of Maryland, Baltimore, MD 21201, USA"},{"name":"University of Maryland Older Americans Independence Center, Department of Medicine, Geriatrics, University of Maryland School of Medicine, Baltimore, MD 21201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charlene","family":"Hafer-Macko","sequence":"additional","affiliation":[{"name":"Fleni Neurological Institute, Buenos Aires C1428AQK, Argentina"},{"name":"Solutions for Developing Countries, University of West Indies, Mona, Kingston 7, Jamaica"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bradley","family":"Hennessie","sequence":"additional","affiliation":[{"name":"NextStep Robotics, Inc., MDC Studios, 300 West Pratt Street, Ste 200, Baltimore, MD 21201, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-3810-9464","authenticated-orcid":false,"given":"Richard","family":"Macko","sequence":"additional","affiliation":[{"name":"NextStep Robotics, Inc., MDC Studios, 300 West Pratt Street, Ste 200, Baltimore, MD 21201, USA"},{"name":"Fleni Neurological Institute, Buenos Aires C1428AQK, Argentina"},{"name":"Solutions for Developing Countries, University of West Indies, Mona, Kingston 7, Jamaica"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,6,29]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e100","DOI":"10.1161\/01.STR.0000180861.54180.FF","article-title":"Management of Adult Stroke Rehabilitation Care: A Clinical Practice Guideline","volume":"36","author":"Duncan","year":"2005","journal-title":"Stroke"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"783","DOI":"10.1177\/1545968310372091","article-title":"Changes in gait symmetry and velocity after stroke: A cross-sectional study from weeks to years after stroke","volume":"24","author":"Patterson","year":"2010","journal-title":"Neurorehabilit. Neural Repair"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"51","DOI":"10.1016\/j.gaitpost.2004.06.009","article-title":"Gait differences between individuals with post-stroke hemiparesis and non-disabled controls at matched speeds","volume":"22","author":"Chen","year":"2005","journal-title":"Gait Posture"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"562","DOI":"10.1016\/j.apmr.2005.12.042","article-title":"The relation between ankle impairments and gait velocity and symmetry in people with stroke","volume":"87","author":"Lin","year":"2006","journal-title":"Arch. Phys. Med. Rehabil."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"27","DOI":"10.1016\/S0003-9993(95)80038-7","article-title":"Recovery of walking function in stroke patients: The Copenhagen Stroke Study","volume":"76","author":"Nakayama","year":"1995","journal-title":"Arch. Phys. Med. Rehabil."},{"key":"ref_6","doi-asserted-by":"crossref","unstructured":"Little, V.L., McGuirk, T.E., and Patten, C. (2014). Impaired limb shortening following stroke: What\u2019s in a name?. PLoS ONE, 9.","DOI":"10.1371\/journal.pone.0110140"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"136","DOI":"10.1016\/0966-6362(96)01063-6","article-title":"Hemiparetic gait following stroke. Part I: Characteristics","volume":"4","author":"Olney","year":"1996","journal-title":"Gait Posture"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"165","DOI":"10.1053\/apmr.2002.28030","article-title":"Fall events among people with stroke living in the community: Circumstances of falls and characteristics of fallers","volume":"83","author":"Hyndman","year":"2002","journal-title":"Arch. Phys. Med. Rehabil."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Shi, B., Chen, X., Yue, Z., Yin, S., Weng, Q., Zhang, X., Wang, J., and Wen, W. (2019). Wearable ankle robots in post-stroke rehabilitation of gait: A systematic review. Front. Neurorobot., 13.","DOI":"10.3389\/fnbot.2019.00063"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"569","DOI":"10.1109\/TRO.2009.2019783","article-title":"Robot-aided neurorehabilitation: A novel robot for ankle rehabilitation","volume":"25","author":"Roy","year":"2009","journal-title":"IEEE Trans. Rob."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"51","DOI":"10.1186\/s12984-016-0158-1","article-title":"Task-specific ankle robotics gait training after stroke: A randomized pilot study","volume":"13","author":"Forrester","year":"2016","journal-title":"J. Neuroeng. Rehabil."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"19","DOI":"10.1186\/s12984-021-00814-6","article-title":"Effects of wearable ankle robotics for stair and over-ground training on sub-acute stroke: A randomized controlled trial","volume":"18","author":"Yeung","year":"2021","journal-title":"J. Neuroeng. Rehabil."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"609","DOI":"10.1136\/bmj.304.6827.609","article-title":"Physiotherapy intervention late after stroke and mobility","volume":"304","author":"Wade","year":"1992","journal-title":"BMJ"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"726","DOI":"10.1177\/1545968309332734","article-title":"Community-based adaptive physical activity program for chronic stroke: Feasibility, safety, and efficacy of the Empoli model","volume":"23","author":"Stuart","year":"2009","journal-title":"Neurorehabil. Neural Repair"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1186\/s12984-025-01834-2","article-title":"Adaptive control ankle robotics training durably improves gait biomechanics in chronic hemiparetic stroke and footdrop","volume":"23","author":"Roy","year":"2026","journal-title":"J. NeuroEng. Rehabil."},{"key":"ref_16","unstructured":"Macko, R.F., and Roy, A. (2022). Method and Apparatus for Providing Economical, Portable Deficit-Adjusted Adaptive Assistance During Movement Phases of an Impaired Ankle. (11,337,622), U.S. Patent."},{"key":"ref_17","unstructured":"Roy, A., Forrester, L.W., and Macko, R.F. (2018). Method and Apparatus for Providing Deficit-Adjusted Adaptive Assistance During Movement Phases of an Impaired Joint. (9,943,459), U.S. Patent."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"325","DOI":"10.1002\/rnj.280","article-title":"Validity of the original and short versions of the Dynamic Gait Index in predicting falls in stroke survivors","volume":"42","author":"An","year":"2017","journal-title":"Rehabil. Nurs."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"406","DOI":"10.1161\/STROKEAHA.116.015309","article-title":"Predicting home and community walking activity poststroke","volume":"48","author":"Fulk","year":"2017","journal-title":"Stroke"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"122","DOI":"10.1097\/NPT.0000000000000257","article-title":"Minimal Detectable Change for Gait Speed Depends on Baseline Speed in Individuals With Chronic Stroke","volume":"43","author":"Lewek","year":"2019","journal-title":"J. Neurol. Phys. Ther."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"2096","DOI":"10.1161\/STROKEAHA.106.475921","article-title":"Improvements in speed-based gait classifications are meaningful","volume":"38","author":"Schmid","year":"2007","journal-title":"Stroke"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"416","DOI":"10.1177\/1545968314552528","article-title":"Walking speed and step length asymmetry modify the energy cost of walking after stroke","volume":"29","author":"Awad","year":"2015","journal-title":"Neurorehabil. Neural Repair"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"314","DOI":"10.1016\/j.gaitpost.2010.11.024","article-title":"Minimal detectable change for gait variables collected during treadmill walking in individuals post-stroke","volume":"33","author":"Kesar","year":"2011","journal-title":"Gait Posture"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"e12027","DOI":"10.1002\/jfa2.12027","article-title":"The relationship of peak ankle dorsiflexion angle with lower extremity biomechanics during walking","volume":"17","author":"Gao","year":"2024","journal-title":"J. Foot Ankle Res."},{"key":"ref_25","doi-asserted-by":"crossref","unstructured":"Guzik, A., Dru\u017cbicki, M., Wolan-Nieroda, A., Turolla, A., and Kiper, P. (2020). Estimating minimal clinically important differences for knee range of motion after stroke. J. Clin. Med., 9.","DOI":"10.3390\/jcm9103305"},{"key":"ref_26","doi-asserted-by":"crossref","unstructured":"Guzik, A., Dru\u017cbicki, M., Perenc, L., Wolan-Nieroda, A., Turolla, A., and Kiper, P. (2021). Establishing the minimal clinically important differences for sagittal hip range of motion in chronic stroke patients. Front. Neurol., 12.","DOI":"10.3389\/fneur.2021.700190"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"757","DOI":"10.1152\/jn.01295.2006","article-title":"Changing motor synergies in chronic stroke","volume":"98","author":"Dipietro","year":"2007","journal-title":"J. Neurophysiol."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"1451","DOI":"10.3390\/neurolint16060108","article-title":"Application of muscle synergies for gait rehabilitation after stroke: Implications for future research","volume":"16","author":"Lee","year":"2024","journal-title":"Neurol. Int."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"44025","DOI":"10.1038\/s41598-025-28818-5","article-title":"Muscle synergy-driven ensemble learning framework for individualized stroke gait rehabilitation","volume":"15","author":"Lee","year":"2025","journal-title":"Sci. Rep."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"98","DOI":"10.1016\/j.jbiomech.2017.08.006","article-title":"Combining muscle synergies and biomechanical analysis to assess gait in stroke patients","volume":"63","author":"Barroso","year":"2017","journal-title":"J. Biomech."},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Amirbekova, M., Kispayeva, T., Adomaviciene, A., Eszhanova, L., Bolshakova, I., and Ospanova, Z. (2025). Systematic review and meta-analysis of effectiveness of robotic therapy in the recovery of motor functions after stroke. Front. Hum. Neurosci., 19.","DOI":"10.3389\/fnhum.2025.1622661"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"64","DOI":"10.1186\/s12984-021-00857-9","article-title":"Effect of robotic-assisted gait training on objective biomechanical measures of gait in persons post-stroke: A systematic review and meta-analysis","volume":"18","author":"Arumugam","year":"2021","journal-title":"J. Neuroeng. Rehabil."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"1140","DOI":"10.1161\/STROKEAHA.111.638148","article-title":"Who may have durable benefit from robotic gait training?: A 2-year follow-up randomized controlled trial in patients with subacute stroke","volume":"43","author":"Morone","year":"2012","journal-title":"Stroke"},{"key":"ref_34","doi-asserted-by":"crossref","unstructured":"Wang, Y., Mukaino, M., Hirano, S., Tanikawa, H., Yamada, J., Ohtsuka, K., Ii, T., Saitoh, E., and Otaka, Y. (2020). Persistent effect of gait exercise assisted robot training on gait ability and lower limb function of patients with subacute stroke: A matched case-control study with three-dimensional gait analysis. Front. Neurorobot., 14.","DOI":"10.3389\/fnbot.2020.00042"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"956","DOI":"10.1109\/TNSRE.2014.2360822","article-title":"Assist-as-needed robot-aided gait training improves walking function in individuals following stroke","volume":"23","author":"Srivastava","year":"2015","journal-title":"IEEE Trans. Neural Syst. Rehabil. Eng."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1701","DOI":"10.1056\/NEJM198812293192604","article-title":"Risk factors for falls among elderly persons living in the community","volume":"319","author":"Tinetti","year":"1988","journal-title":"N. Engl. J. Med."},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"123","DOI":"10.1097\/00002060-199903000-00007","article-title":"Analysis of the clinical factors determining natural and maximal gait speeds in adults with a stroke","volume":"78","author":"Nadeau","year":"1999","journal-title":"Am. J. Phys. Med. Rehabil."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"46","DOI":"10.1519\/00139143-200932020-00002","article-title":"White paper: \u201cwalking speed: The sixth vital sign\u201d","volume":"32","author":"Fritz","year":"2009","journal-title":"J. Geriatr. Phys. Ther."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"49","DOI":"10.1097\/NPT.0000000000000303","article-title":"Clinical Practice Guideline to Improve Locomotor Function Following Chronic Stroke, Incomplete Spinal Cord Injury, and Brain Injury","volume":"44","author":"Hornby","year":"2020","journal-title":"J. Neurol. Phys. Ther."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"2532","DOI":"10.1161\/STR.0000000000000022","article-title":"Physical activity and exercise recommendations for stroke survivors: A statement for healthcare professionals from the American Heart Association\/American Stroke Association","volume":"45","author":"Billinger","year":"2014","journal-title":"Stroke"},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"613","DOI":"10.1097\/PHM.0000000000001174","article-title":"Exercise training guidelines for multiple sclerosis, stroke, and Parkinson Disease: Rapid review and synthesis","volume":"98","author":"Kim","year":"2019","journal-title":"Am. J. Phys. Med. Rehabil."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"151","DOI":"10.1016\/j.jbiomech.2019.05.011","article-title":"Improved walking function in laboratory does not guarantee increased community walking in stroke survivors: Potential role of gait biomechanics","volume":"91","author":"Ardestani","year":"2019","journal-title":"J. Biomech."}],"container-title":["Medicina"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1648-9144\/62\/7\/1250\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,29]],"date-time":"2026-06-29T07:27:33Z","timestamp":1782718053000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1648-9144\/62\/7\/1250"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,6,29]]},"references-count":42,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2026,7]]}},"alternative-id":["medicina62071250"],"URL":"https:\/\/doi.org\/10.3390\/medicina62071250","relation":{},"ISSN":["1648-9144"],"issn-type":[{"value":"1648-9144","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,6,29]]}}}