{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,3]],"date-time":"2026-03-03T16:19:21Z","timestamp":1772554761530,"version":"3.50.1"},"reference-count":22,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2023,12,26]],"date-time":"2023-12-26T00:00:00Z","timestamp":1703548800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"NK244D projects of the Korea Institute of Machinery and Materials"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Amputees typically experience changes in residual limb volume in their daily lives. It causes an uncomfortable fit of the socket by applying high pressure on the sensitive area of the residual limb or by loosening the socket. In this study, we developed a transfemoral prosthetic socket for above-the-knee amputees that ensures a good socket fit by maintaining uniform and constant contact pressure despite volume changes in the residual limb. The socket has two air bladders in the posterior femoral region, and the pneumatic controller is located on the tibia of the prosthesis. The pneumatic system aims to minimize unstable fitting of the socket and improve walking performance by inflating or deflating the air bladder. The developed socket autonomously maintains the air pressure inside the prosthetic socket at a steady-state error of 3 mmHg or less by adjusting the amount of air in the air bladder via closed-loop control. In the clinical trial, amputee participants walked on flat and inclined surfaces. The displacement between the residual limb and socket during the gait cycle was reduced by up to 33.4% after air injection into the socket. The inflatable bladder increased the knee flexion angle on the affected side, resulting in increased stride length and gait velocity. The pneumatic socket provides a stable and comfortable walking experience not only when walking on flat ground but also on slopes.<\/jats:p>","DOI":"10.3390\/s24010133","type":"journal-article","created":{"date-parts":[[2023,12,27]],"date-time":"2023-12-27T02:58:12Z","timestamp":1703645892000},"page":"133","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["A Pneumatically Controlled Prosthetic Socket for Transfemoral Amputees"],"prefix":"10.3390","volume":"24","author":[{"given":"Kang-Ho","family":"Lee","sequence":"first","affiliation":[{"name":"Daegu Research Center for Medical Devices, Korea Institute of Machinery and Materials, Daegu 42994, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hyun-Seok","family":"Heo","sequence":"additional","affiliation":[{"name":"Shinsegae Prosthetic Center, Daegu 41710, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5089-8387","authenticated-orcid":false,"given":"Jeongmin","family":"Kim","sequence":"additional","affiliation":[{"name":"Daegu Research Center for Medical Devices, Korea Institute of Machinery and Materials, Daegu 42994, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jang Hyuk","family":"Cho","sequence":"additional","affiliation":[{"name":"Department of Rehabilitation Medicine, Keimyung University Dongsan Hospital, Keimyung University School of Medicine, Daegu 42601, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9355-8326","authenticated-orcid":false,"given":"Kyoung Tae","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Rehabilitation Medicine, Keimyung University Dongsan Hospital, Keimyung University School of Medicine, Daegu 42601, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jeong-Yong","family":"Hur","sequence":"additional","affiliation":[{"name":"Shinsegae Prosthetic Center, Daegu 41710, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jang Hwan","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Rehabilitation Technology, Graduate School of Hanseo University, Seosan 31962, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yongkoo","family":"Lee","sequence":"additional","affiliation":[{"name":"Daegu Research Center for Medical Devices, Korea Institute of Machinery and Materials, Daegu 42994, Republic of Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,12,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2453","DOI":"10.2337\/dc20-0586","article-title":"National and State-Level Trends in Nontraumatic Lower-Extremity Amputation among U.S. Medicare Beneficiaries with Diabetes, 2000\u20132017","volume":"43","author":"Harding","year":"2020","journal-title":"Diabetes Care"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"93","DOI":"10.1186\/s12984-020-00711-4","article-title":"Technology for monitoring everyday prosthesis use: A systematic review","volume":"17","author":"Chadwell","year":"2020","journal-title":"J. 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