{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,19]],"date-time":"2026-03-19T03:38:16Z","timestamp":1773891496850,"version":"3.50.1"},"reference-count":30,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2023,5,3]],"date-time":"2023-05-03T00:00:00Z","timestamp":1683072000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Surg."],"abstract":"<jats:sec><jats:title>Purpose<\/jats:title><jats:p>Evaluate the ability of pre-contoured rods to induce thoracic kyphosis (TK) in human cadaveric spines and determine the effectiveness of sequential surgical adolescent idiopathic scoliosis (AIS) release procedures.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>Six thoracolumbar (T3-L2) spine specimens were instrumented with pedicle screws bilaterally (T4\u2013T12). Over correction using pre-contoured rods was performed for intact condition and Cobb angle was measured. Rod radius of curvature (RoC) was measured pre- and post-reduction. The process was repeated following sequential release procedures of (1) interspinous and supraspinous ligaments (ISL); (2) ligamentum flavum; (3) Ponte osteotomy; (4) posterior longitudinal ligament (PLL); and (5) transforaminal discectomy. Cobb measurements determined the effective contribution of release on TK and RoC data displayed effects of reduction to the rods.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>The intact TK (T4\u201312) was 38.0\u00b0 and increased to 51.7\u00b0 with rod reduction and over correction. Each release resulted in 5\u00b0\u20137\u00b0of additional kyphosis; the largest releases were ISL and PLL. All releases resulted in significant increases in kyphosis compared to intact with rod reduction and over correction. Regionally, kyphosis increased \u223c2\u00b0 for each region following successive releases. Comparing RoC before and after reduction showed significant 6\u00b0 loss in rod curvature independent of release type.<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusion<\/jats:title><jats:p>Kyphosis increased in the thoracic spine using pre-contoured and over corrected rods. Subsequent posterior releases provided a substantial, meaningful clinical change in the ability to induce additional kyphosis. Regardless of the number of releases, the ability of the rods to induce and over correct kyphosis was reduced following reduction.<\/jats:p><\/jats:sec>","DOI":"10.3389\/fsurg.2023.1064037","type":"journal-article","created":{"date-parts":[[2023,5,3]],"date-time":"2023-05-03T05:25:49Z","timestamp":1683091549000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["The effectiveness of pre-contoured titanium alloy rods in inducing thoracic kyphosis after sequential spinal releases in an in vitro biomechanical model"],"prefix":"10.3389","volume":"10","author":[{"given":"Jinhui","family":"Shi","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nathaniel R.","family":"Ordway","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mike H.","family":"Sun","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stephen A.","family":"Albanese","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"William F.","family":"Lavelle","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2023,5,3]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"1889","DOI":"10.1007\/s00586-019-06083-1","article-title":"Sagittal balance of the spine","volume":"28","author":"LeHuec","year":"2019","journal-title":"Eur Spine J"},{"key":"B2","doi-asserted-by":"publisher","first-page":"2024","DOI":"10.1097\/01.brs.0000179086.30449.96","article-title":"The impact of positive sagittal balance in adult spinal deformity","volume":"30","author":"Glassman","year":"2005","journal-title":"Spine"},{"key":"B3","doi-asserted-by":"publisher","first-page":"387","DOI":"10.1097\/00007632-200202150-00012","article-title":"Adult scoliosis: a quantitative radiographic and clinical analysis","volume":"27","author":"Schwab","year":"2002","journal-title":"Spine"},{"key":"B4","doi-asserted-by":"publisher","first-page":"E599","DOI":"10.1097\/BRS.0b013e3181aad219","article-title":"Pelvic tilt and truncal inclination: two key radiographic parameters in the setting of adults with spinal deformity","volume":"34","author":"Lafage","year":"2009","journal-title":"Spine"},{"key":"B5","volume-title":"Anatomy, descriptive and surgical. 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