{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:12:14Z","timestamp":1760058734918,"version":"build-2065373602"},"reference-count":37,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2025,4,23]],"date-time":"2025-04-23T00:00:00Z","timestamp":1745366400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Taiwan\u2019s National Science and Technology Council","award":["MOST 103-2314-B-038-027","KMUH106-6M42","KMTTH-111-019"],"award-info":[{"award-number":["MOST 103-2314-B-038-027","KMUH106-6M42","KMTTH-111-019"]}]},{"DOI":"10.13039\/501100011645","name":"Kaohsiung Medical University Hospital","doi-asserted-by":"publisher","award":["MOST 103-2314-B-038-027","KMUH106-6M42","KMTTH-111-019"],"award-info":[{"award-number":["MOST 103-2314-B-038-027","KMUH106-6M42","KMTTH-111-019"]}],"id":[{"id":"10.13039\/501100011645","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Kaohsiung Municipal Ta-Tung Hospital","award":["MOST 103-2314-B-038-027","KMUH106-6M42","KMTTH-111-019"],"award-info":[{"award-number":["MOST 103-2314-B-038-027","KMUH106-6M42","KMTTH-111-019"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Bioengineering"],"abstract":"<jats:p>Background\/Objectives: The pullout failure of conventional locking screws (LSs, screws with a locking mechanism) may occur in patients with osteoporosis, particularly when inserted near joints or across periarticular fractures (e.g., proximal humerus). The two-part locking cancellous screw modification (TP-LCS, screws composed of two parts) in metaphyseal cancellous bone is hypothesized to increase bone purchase and holding power. This study aimed to test the hypothesized advantages of TP-LCS over LSs. Methods: An MTS 370 series frame with an axial\/torsional load cell was used to test driving torque and axial pullout strength, following ASTM F543-07 standards. The TP-LCS group featured a newly modified screw design made from titanium alloy (Ti6Al4V), while conventional LSs (Synthes) were used for the control group. Statistical significance was assessed for selected comparisons relevant to the research objectives, including driving torque and axial pullout strength. Results: The driving torque test showed that TP-LCS had a significantly higher maximum insertion torque (4.9 \u00b1 0.4 N\u00b7cm) compared to LSs (4.2 \u00b1 0.4 N\u00b7cm) (p = 0.0269), although no significant difference was found in maximum removal torque (p = 0.1046). The axial pullout test revealed that TP-LCS had significantly higher pullout strength (223.5 \u00b1 12.2 N) compared to LSs (203.5 \u00b1 11.5 N) (p = 0.0284). Failure during the axial pullout test often involved cracking of the test block material around the screw threads, causing the screw to pull out. Conclusions: These results support the hypothesis that TP-LCS may offer improved axial pullout resistance compared to LSs, making it a potentially beneficial modification for LSs in osteoporotic metaphyseal regions or near joints. This study provides biomechanical insights into the advantages of the modified screw design over conventional LSs.<\/jats:p>","DOI":"10.3390\/bioengineering12050444","type":"journal-article","created":{"date-parts":[[2025,4,23]],"date-time":"2025-04-23T12:04:33Z","timestamp":1745409873000},"page":"444","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Modification of a Two-Part Cancellous Locking Screw: A Pilot Study on Increasing Resistance to Axial Pullout Strength"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8832-0345","authenticated-orcid":false,"given":"Chia-Hao","family":"Hsu","sequence":"first","affiliation":[{"name":"Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, No. 100, Shih-Chuan 1st Road, Sanmin District, Kaohsiung 80708, Taiwan"},{"name":"Department of Orthopedics, Kaohsiung Medical University Hospital, No. 100, Tzyou 1st Road, Sanmin District, Kaohsiung 80756, Taiwan"},{"name":"Department of Orthopedics, College of Medicine, Kaohsiung Medical University, No. 100, Shiquan 1st Road, Sanmin District, Kaohsiung 80708, Taiwan"},{"name":"Orthopaedic Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"},{"name":"Regenerative Medicine and Cell Therapy Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4997-1081","authenticated-orcid":false,"given":"Nin-Chieh","family":"Hsu","sequence":"additional","affiliation":[{"name":"Department of Internal Medicine, College of Medicine, National Taiwan University, Taipei 100225, Taiwan"},{"name":"Division of Hospital Medicine, Department of Internal Medicine, Taipei City Hospital Zhongxing Branch, Taipei 103212, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4191-2183","authenticated-orcid":false,"given":"Sung-Yen","family":"Lin","sequence":"additional","affiliation":[{"name":"Department of Orthopedics, Kaohsiung Medical University Hospital, No. 100, Tzyou 1st Road, Sanmin District, Kaohsiung 80756, Taiwan"},{"name":"Orthopaedic Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"},{"name":"Regenerative Medicine and Cell Therapy Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"},{"name":"School of Post-Baccalaureate Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"},{"name":"Department of Orthopedics, Kaohsiung Medical University Gangshan Hospital, Kaohsiung 820, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7194-9147","authenticated-orcid":false,"given":"Cheng-Chang","family":"Lu","sequence":"additional","affiliation":[{"name":"Department of Orthopedics, Kaohsiung Medical University Hospital, No. 100, Tzyou 1st Road, Sanmin District, Kaohsiung 80756, Taiwan"},{"name":"Department of Orthopedics, College of Medicine, Kaohsiung Medical University, No. 100, Shiquan 1st Road, Sanmin District, Kaohsiung 80708, Taiwan"},{"name":"Orthopaedic Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"},{"name":"Regenerative Medicine and Cell Therapy Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"},{"name":"Department of Orthopedics, Kaohsiung Municipal Hsiao-Kang Hospital, Kaohsiung Medical University, Kaohsiung 812, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yin-Chih","family":"Fu","sequence":"additional","affiliation":[{"name":"Department of Orthopedics, Kaohsiung Medical University Hospital, No. 100, Tzyou 1st Road, Sanmin District, Kaohsiung 80756, Taiwan"},{"name":"Department of Orthopedics, College of Medicine, Kaohsiung Medical University, No. 100, Shiquan 1st Road, Sanmin District, Kaohsiung 80708, Taiwan"},{"name":"Orthopaedic Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"},{"name":"Regenerative Medicine and Cell Therapy Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8638-1021","authenticated-orcid":false,"given":"Hsuan-Ti","family":"Huang","sequence":"additional","affiliation":[{"name":"Department of Orthopedics, Kaohsiung Medical University Hospital, No. 100, Tzyou 1st Road, Sanmin District, Kaohsiung 80756, Taiwan"},{"name":"Department of Orthopedics, College of Medicine, Kaohsiung Medical University, No. 100, Shiquan 1st Road, Sanmin District, Kaohsiung 80708, Taiwan"},{"name":"Orthopaedic Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"},{"name":"Regenerative Medicine and Cell Therapy Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"},{"name":"Department of Orthopedics, Kaohsiung Medical University Gangshan Hospital, Kaohsiung 820, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8941-4792","authenticated-orcid":false,"given":"Chung-Hwan","family":"Chen","sequence":"additional","affiliation":[{"name":"Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, No. 100, Shih-Chuan 1st Road, Sanmin District, Kaohsiung 80708, Taiwan"},{"name":"Department of Orthopedics, Kaohsiung Medical University Hospital, No. 100, Tzyou 1st Road, Sanmin District, Kaohsiung 80756, Taiwan"},{"name":"Department of Orthopedics, College of Medicine, Kaohsiung Medical University, No. 100, Shiquan 1st Road, Sanmin District, Kaohsiung 80708, Taiwan"},{"name":"Orthopaedic Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"},{"name":"Regenerative Medicine and Cell Therapy Research Center, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pei-Hsi","family":"Chou","sequence":"additional","affiliation":[{"name":"Graduate Institute of Clinical Medicine, College of Medicine, Kaohsiung Medical University, No. 100, Shih-Chuan 1st Road, Sanmin District, Kaohsiung 80708, Taiwan"},{"name":"Department of Orthopedics, Kaohsiung Medical University Hospital, No. 100, Tzyou 1st Road, Sanmin District, Kaohsiung 80756, Taiwan"},{"name":"Department of Orthopedics, College of Medicine, Kaohsiung Medical University, No. 100, Shiquan 1st Road, Sanmin District, Kaohsiung 80708, Taiwan"},{"name":"Department of Sports Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"488","DOI":"10.1097\/00005131-200409000-00003","article-title":"Biomechanics of locked plates and screws","volume":"18","author":"Egol","year":"2004","journal-title":"J. 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Surg."}],"container-title":["Bioengineering"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2306-5354\/12\/5\/444\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T17:20:25Z","timestamp":1760030425000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2306-5354\/12\/5\/444"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,4,23]]},"references-count":37,"journal-issue":{"issue":"5","published-online":{"date-parts":[[2025,5]]}},"alternative-id":["bioengineering12050444"],"URL":"https:\/\/doi.org\/10.3390\/bioengineering12050444","relation":{},"ISSN":["2306-5354"],"issn-type":[{"type":"electronic","value":"2306-5354"}],"subject":[],"published":{"date-parts":[[2025,4,23]]}}}