{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,24]],"date-time":"2026-07-24T16:27:48Z","timestamp":1784910468240,"version":"3.55.0"},"reference-count":25,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2025,3,11]],"date-time":"2025-03-11T00:00:00Z","timestamp":1741651200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Purpose: To explore the clinical outcomes associated with screw loosening after S2 alar-iliac (SAI) screw fixation for adult spinal deformity (ASD). Overview of the literature: SAI fixation is widely used in ASD corrective surgery; despite the biomechanical advantages of this screw, complications such as screw loosening remain a significant concern. Methods: We retrospectively reviewed 27 patients undergoing corrective surgery for ASD using SAI as the distal fixation point at a single institution between February 2013 and February 2018. Patients were divided into non-loosening (N) and loosening (L) groups based on radiological evidence of screw loosening (radiolucent area of 1 mm around the screw) and compared for demographic characteristics, bone mineral density (T-score), spinal alignment parameters, and patient-reported outcome using the Japanese Orthopaedic Association Back Pain Evaluation Questionnaire (JOABPEQ) scores. Results: Screw loosening was observed in 78% of patients (n = 21\/27); however, there were no statistically significant differences between the N and L groups in terms of the preoperative and 5-year postoperative JOABPEQ scores (p &gt; 0.05 across all domains) and spinal sagittal alignment (p &gt; 0.05). The improvements achieved through corrective surgery were largely maintained regardless of the presence of screw loosening. Conclusions: SAI screw loosening is a common sequela in ASD surgery; however, its loosening might not affect long-term clinical outcomes. Therefore, the choice of fixation should be individualized based on patient factors such as age and bone quality.<\/jats:p>","DOI":"10.3390\/jcm14061881","type":"journal-article","created":{"date-parts":[[2025,3,11]],"date-time":"2025-03-11T06:52:30Z","timestamp":1741675950000},"page":"1881","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Clinical Outcomes Associated with Screw Loosening in S2 Alar-Iliac Fixation in Adult Spinal Deformity"],"prefix":"10.3390","volume":"14","author":[{"given":"Yasuhiro","family":"Nagatani","sequence":"first","affiliation":[{"name":"Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hiroaki","family":"Nakashima","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0488-5259","authenticated-orcid":false,"given":"Tokumi","family":"Kanemura","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3496-5551","authenticated-orcid":false,"given":"Mikito","family":"Tsushima","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hiroyuki","family":"Tomita","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kazuaki","family":"Morishita","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hiroki","family":"Oyama","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sadayuki","family":"Ito","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9681-2422","authenticated-orcid":false,"given":"Naoki","family":"Segi","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0003-3447-1628","authenticated-orcid":false,"given":"Jun","family":"Ouchida","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0004-3005-2570","authenticated-orcid":false,"given":"Ippei","family":"Yamauchi","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0005-5473-9817","authenticated-orcid":false,"given":"Yukihito","family":"Ode","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuya","family":"Okada","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Shiro","family":"Imagama","sequence":"additional","affiliation":[{"name":"Department of Orthopedic Surgery, Nagoya University Graduate School of Medicine, Nagoya 466-8560, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,3,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1828","DOI":"10.1097\/BRS.0b013e3181a13c08","article-title":"Sagittal plane considerations and the pelvis in the adult patient","volume":"34","author":"Schwab","year":"2009","journal-title":"Spine (Phila Pa 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