{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T02:17:03Z","timestamp":1788229023506,"version":"build-2803163510"},"reference-count":22,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,8,31]],"date-time":"2026-08-31T00:00:00Z","timestamp":1788134400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>The amount of rod contour is a critical factor that influences sagittal and coronal alignment for posterior spinal fusion. Distraction techniques to correct spinal deformity, which are often three-dimensional (3D) in nature, are known to cause rod deformation from the ideal, planned rod curvature. Therefore, surgeons often overbend rods to account for this phenomenon. Currently, there is no agreed-upon method to scientifically quantify rod unbending, and no methods offer a 3D analysis. The proposed methodology addresses this gap. By aligning the 3D rod centerlines, the segmented area enclosed between the two lines serves as a measure of rod deformation. This paper presents the foundational principles and concepts for quantifying 3D rod deformation. With further research and clinical implementation, this methodology has the potential to provide valuable surgical insight, which could improve postoperative spinal alignment and outcomes.<\/jats:p>","DOI":"10.3390\/bioengineering13091012","type":"journal-article","created":{"date-parts":[[2026,9,1]],"date-time":"2026-09-01T01:05:26Z","timestamp":1788224726000},"page":"1012","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Three-Dimensional Measurement and Analysis of Rod Deformation for Spinal Deformity Correction: A Novel Methodology"],"prefix":"10.3390","volume":"13","author":[{"given":"Sam W.","family":"Hendricks","sequence":"first","affiliation":[{"name":"Department of Orthopedic Surgery, University of Minnesota, Minneapolis, 55454 MN, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0001-9004-6912","authenticated-orcid":false,"given":"Cale J.","family":"Hendricks","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, University of Minnesota, Minneapolis, 55454 MN, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arin M.","family":"Ellingson","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, University of Minnesota, Minneapolis, 55454 MN, USA"},{"name":"Department of Family Medicine and Community Health, University of Minnesota, Minneapolis, MN 55454, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"suffix":"Jr.","given":"David W.","family":"Polly","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, University of Minnesota, Minneapolis, 55454 MN, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0385-4023","authenticated-orcid":false,"given":"Arthur G.","family":"Erdman","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN 55454, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"752","DOI":"10.21037\/jss-20-492","article-title":"Trends in lumbar spinal fusion\u2014A literature review","volume":"6","author":"Reisener","year":"2020","journal-title":"J. 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Spine Surg."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"12622","DOI":"10.1038\/s41598-021-92187-y","article-title":"In vivo deformation of anatomically pre-bent rods in thoracic adolescent idiopathic scoliosis","volume":"11","author":"Sudo","year":"2021","journal-title":"Sci. Rep."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"177","DOI":"10.21037\/jss-24-1","article-title":"Pre-contoured patient-specific rods result in superior immediate sagittal plane alignment than surgeon contoured rods in adolescent idiopathic scoliosis","volume":"10","author":"Jabbouri","year":"2024","journal-title":"J. Spine Surg."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"425","DOI":"10.1177\/2192568221998371","article-title":"Accuracy of Rod Contouring to Desired Angles with and Without a Template: Implications for Achieving Desired Spinal Alignment and Outcomes","volume":"13","author":"Sardi","year":"2023","journal-title":"Glob. Spine J."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1356","DOI":"10.1109\/TBME.2006.889205","article-title":"A Novel System for the 3-D Reconstruction of the Human Spine and Rib Cage from Biplanar X-Ray Images","volume":"54","author":"Cheriet","year":"2007","journal-title":"IEEE Trans. Biomed. 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