{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T15:57:38Z","timestamp":1781798258038,"version":"3.54.5"},"reference-count":27,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T00:00:00Z","timestamp":1781740800000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T00:00:00Z","timestamp":1781740800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"funder":[{"DOI":"10.13039\/501100002551","name":"Seoul National University","doi-asserted-by":"crossref","id":[{"id":"10.13039\/501100002551","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Arch Orthop Trauma Surg"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>Traditionally, interbody cages feature a central cavity for graft packing. However, for bioactive glass-ceramic (BGS-7) spacers achieving fusion via surface-mediated osseointegration, this cavity may be biologically redundant and structurally disadvantageous. We compared radiological and clinical outcomes of plated anterior cervical discectomy and fusion (ACDF) using BGS-7 spacers with or without a central cavity.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We retrospectively reviewed patients undergoing plated ACDF using solid non-cavity (17 patients, 24 levels) or central-cavity (17 patients, 33 levels) BGS-7 spacers. Radiographic fusion was evaluated using dynamic interspinous distance (primary, \u2264 2\u00a0mm) and segmental angular motion (secondary, \u2264 4\u00b0), alongside CT-based osseointegration (direct contact\u2009\u2265\u200950%). Subsidence (\u2265\u20092\u00a0mm) and clinical outcomes were evaluated at 12 months.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      Both groups demonstrated comparable 12-month clinical improvements (\n                      <jats:italic>p<\/jats:italic>\n                      \u2009&gt;\u20090.05). Radiographic fusion rates were equivalent between non-cavity and central-cavity groups based on the primary distance (91.7% vs. 84.8%,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.687) and secondary angular criteria (79.2% vs. 63.6%,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.331). The non-cavity group showed a trend toward superior segmental stability, with a smaller dynamic gap distance (0.82\u2009\u00b1\u20090.64\u00a0mm vs. 1.53\u2009\u00b1\u20091.99\u00a0mm,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20090.064). CT-based fusion perfectly matched (90.5% vs. 90.9%,\n                      <jats:italic>p<\/jats:italic>\n                      \u2009=\u20091.000). Subsidence rates were comparably low (12.5% vs. 12.1%), with no spacer breakage.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>In plated ACDF, adding a central cavity to BGS-7 spacers confers no measurable advantage over the solid design. Solid spacers inherently preserve maximum endplate contact area for optimal load-sharing and surface-mediated fusion. Eliminating the cavity and supplemental grafts avoids logical redundancy, donor-site morbidity, and unnecessary healthcare costs.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s00402-026-06389-y","type":"journal-article","created":{"date-parts":[[2026,6,18]],"date-time":"2026-06-18T15:42:53Z","timestamp":1781797373000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Is a central cavity necessary for bioactive glass-ceramic spacers in plated ACDF? A retrospective comparison of solid versus cavity designs"],"prefix":"10.1007","volume":"146","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-0127-9456","authenticated-orcid":false,"given":"Tae Hoon","family":"Kang","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Geumho","family":"Lee","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Byungjun","family":"Kang","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeongwoon","family":"Han","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Minjoon","family":"Cho","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2141-0266","authenticated-orcid":false,"given":"Jae Hyup","family":"Lee","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,6,18]]},"reference":[{"issue":"4","key":"6389_CR1","doi-asserted-by":"publisher","first-page":"446","DOI":"10.1177\/2192568218774576","volume":"9","author":"ZB Cheung","year":"2019","unstructured":"Cheung ZB, Gidumal S, White S et al (2019) Comparison of anterior cervical discectomy and fusion with a stand-alone interbody cage versus a conventional cage-plate technique: a systematic review and meta-analysis. 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