{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,14]],"date-time":"2026-07-14T04:55:50Z","timestamp":1784004950331,"version":"3.55.0"},"reference-count":25,"publisher":"Public Library of Science (PLoS)","issue":"12","license":[{"start":{"date-parts":[[2023,12,11]],"date-time":"2023-12-11T00:00:00Z","timestamp":1702252800000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Poznan University of Medical Sciences and Poznan University of Technology","award":["0614\/SBAD\/1565, 0614\/SBAD\/1579 and 0614\/SBAD\/1547"],"award-info":[{"award-number":["0614\/SBAD\/1565, 0614\/SBAD\/1579 and 0614\/SBAD\/1547"]}]},{"name":"ChM Sp. z o.o., Lewickie, Poland"}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS ONE"],"abstract":"<jats:sec id=\"sec001\">\n<jats:title>Purpose<\/jats:title>\n<jats:p>Polyaxial locking plates rely on the alignment between the thread-to-thread connections of the screw head and the plate hole. These implants have provided substantial support for surgeons. In particular, extended screw positioning have proven to be beneficial in the fixation of challenging fractures. This study aimed to investigate the mechanical properties of ChM 5.0 ChLP polyaxial screws inserted in off-axis trajectories, including multiple insertions and to correlate these parameters with the screw head and the plate hole thread-to-thread engagement.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec002\">\n<jats:title>Methods<\/jats:title>\n<jats:p>Polyaxial locking screws were inserted into the plates at various angles (0\u00b0,10\u00b0,15\u00b0, -15\u00b0 off-axis). Multiple time inserted screws were placed firstly at 15\u00b0, then 0\u00b0 and finally -15\u00b0 off-axis in the same plate hole. A microCT scan of the plate-hole and screw-head interface was conducted before destructive tests. Representative screws from each group were also examined by Scanning Electron Microscope.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec003\">\n<jats:title>Results<\/jats:title>\n<jats:p>The standard insertion at 0\u00b0 sustained the greatest maximum bending strength without relocation in the screw hole. Screws inserted at 10\u00b0 and 15\u00b0 (one time) showed a significant reduction in load-to-failure of up to 36% and 55%, (p = 0.001) (p = 0.001) respectively. Screws inserted at -15\u00b0 after a maximum of three multiple insertions with angle shift, showed a total reduction in force of up to 70% (p = 0.001). A microCT analysis of thread engagement showed significant correlations. However, the results obtained for multiple insertions were highly variable.<\/jats:p>\n<\/jats:sec>\n<jats:sec id=\"sec004\">\n<jats:title>Conclusions<\/jats:title>\n<jats:p>ChM 5.0 ChLP polyaxial locking system has valuable properties that foster fracture fixation, providing various surgical options. Nevertheless, the freedom of off-axis placement and multiple insertions of the screws comes at the price of reduced force. When possible surgeons should minimize the angles of insertions.<\/jats:p>\n<\/jats:sec>","DOI":"10.1371\/journal.pone.0295526","type":"journal-article","created":{"date-parts":[[2023,12,11]],"date-time":"2023-12-11T18:23:47Z","timestamp":1702319027000},"page":"e0295526","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":7,"title":["Effect of screw angulation and multiple insertions on load-to-failure of polyaxial locking system"],"prefix":"10.1371","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8200-742X","authenticated-orcid":true,"given":"Jakub","family":"Glowacki","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4715-6358","authenticated-orcid":true,"given":"Tomasz","family":"Bartkowiak","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Piotr","family":"Paczos","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2300-0834","authenticated-orcid":true,"given":"Patryk","family":"Mietlinski","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8153-8774","authenticated-orcid":true,"given":"Pawel","family":"Zawadzki","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lukasz","family":"Lapaj","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2023,12,11]]},"reference":[{"key":"pone.0295526.ref001","doi-asserted-by":"crossref","first-page":"S30","DOI":"10.1016\/S0020-1383(03)00255-9","article-title":"Stabilization of proximal tibial fractures with the LIS-System: Early clinical experience in Berlin","volume":"34","author":"M Sch\u00fctz","year":"2003","journal-title":"Injury"},{"key":"pone.0295526.ref002","doi-asserted-by":"crossref","first-page":"483","DOI":"10.1097\/00005131-200409000-00002","article-title":"Locked Internal Fixator","volume":"18","author":"MJ K\u00e4\u00e4b","year":"2004","journal-title":"J Orthop Trauma"},{"key":"pone.0295526.ref003","doi-asserted-by":"crossref","first-page":"1358","DOI":"10.1016\/j.injury.2013.06.013","article-title":"A biomechanical study comparing polyaxial locking screw mechanisms","volume":"44","author":"J Hebert-Davies","year":"2013","journal-title":"Injury"},{"key":"pone.0295526.ref004","article-title":"Was leistet die winkelstabile Plattenosteosynthese bei der distalen Radiusfraktur des alten Menschen?","author":"M Walz","year":"2004","journal-title":"Unfallchirurg"},{"key":"pone.0295526.ref005","doi-asserted-by":"crossref","first-page":"e6","DOI":"10.2106\/JBJS.RVW.17.00049","article-title":"Not All Polyaxial Locking Screw Technologies Are Created Equal","volume":"6","author":"B Schoch","year":"2018","journal-title":"JBJS Rev"},{"key":"pone.0295526.ref006","doi-asserted-by":"crossref","DOI":"10.1515\/bmt-2012-0105","article-title":"Are there any differences in various polyaxial locking systems? A mechanical study of different locking screws in multidirectional angular stable distal radius plates","volume":"58","author":"I Mehling","year":"2013","journal-title":"Biomedizinische Technik\/Biomedical Engineering"},{"key":"pone.0295526.ref007","unstructured":"ChM-5.0 ChLP distal humerus plates. [cited 18 Jul 2023]. https:\/\/chm.eu\/uploads\/ST-80-511_50CHLP_DISTAL-HUMERUS-PLATES_rev_P-000_2019-06_EN_PASS.pdf"},{"key":"pone.0295526.ref008","doi-asserted-by":"crossref","first-page":"465","DOI":"10.1111\/j.1532-950X.2014.12095.x","article-title":"In Vitro Biomechanical Comparison of 3.5 String of Pearl Plate Fixation to 3.5 Locking Compression Plate Fixation in a Canine Fracture Gap Model","volume":"43","author":"R-C Malenfant","year":"2014","journal-title":"Veterinary Surgery"},{"key":"pone.0295526.ref009","doi-asserted-by":"crossref","first-page":"645","DOI":"10.1097\/BOT.0b013e3181a567c8","article-title":"Biomechanical Comparison of Polyaxial-Type Locking Plates and a Fixed-Angle Locking Plate for Internal Fixation of Distal Femur Fractures","volume":"23","author":"RJ Otto","year":"2009","journal-title":"J Orthop Trauma"},{"key":"pone.0295526.ref010","doi-asserted-by":"crossref","first-page":"88","DOI":"10.3415\/VCOT-14-03-0046","article-title":"Mechanical performance in axial compression of a titanium polyaxial locking plate system in a fracture gap model","volume":"28","author":"AW Tomlinson","year":"2015","journal-title":"Veterinary and Comparative Orthopaedics and Traumatology"},{"key":"pone.0295526.ref011","doi-asserted-by":"crossref","first-page":"186","DOI":"10.3415\/VCOT-12-03-0043","article-title":"The effect of screw angulation and insertion torque on the push-out strength of polyaxial locking screws and the single cycle to failure in bending of polyaxial locking plates","volume":"26","author":"BW Bufkin","year":"2013","journal-title":"Veterinary and Comparative Orthopaedics and Traumatology"},{"key":"pone.0295526.ref012","doi-asserted-by":"crossref","first-page":"988","DOI":"10.1002\/jor.22851","article-title":"Concept of variable angle locking-evolution and mechanical evaluation of a recent technology","volume":"33","author":"M Lenz","year":"2015","journal-title":"Journal of Orthopaedic Research"},{"key":"pone.0295526.ref013","doi-asserted-by":"crossref","first-page":"408","DOI":"10.3415\/VCOT-11-04-0061","article-title":"Single cycle to failure in bending of three standard and five locking plates and plate constructs","volume":"24","author":"CA Blake","year":"2011","journal-title":"Veterinary and Comparative Orthopaedics and Traumatology"},{"key":"pone.0295526.ref014","doi-asserted-by":"crossref","first-page":"172","DOI":"10.3415\/VCOT-16-07-0111","article-title":"Single cycle to failure in bending of three titanium polyaxial locking plates","volume":"30","author":"C Eid","year":"2017","journal-title":"Veterinary and Comparative Orthopaedics and Traumatology"},{"key":"pone.0295526.ref015","doi-asserted-by":"crossref","first-page":"339","DOI":"10.1055\/s-0042-1750431","article-title":"What Is the Cost of Off-Axis Insertion of Locking Screws? A Biomechanical Comparison of a 3.5 mm Fixed-Angle and 3.5 mm Variable-Angle Stainless Steel Locking Plate Systems","volume":"35","author":"J Kaczmarek","year":"2022","journal-title":"Veterinary and Comparative Orthopaedics and Traumatology"},{"key":"pone.0295526.ref016","doi-asserted-by":"crossref","first-page":"316","DOI":"10.1055\/s-0040-1709728","article-title":"How Do the Locking Screws Lock? A Micro-CT Study of 3.5-mm Locking Screw Mechanism","volume":"33","author":"J Kaczmarek","year":"2020","journal-title":"Veterinary and Comparative Orthopaedics and Traumatology"},{"key":"pone.0295526.ref017","unstructured":"American Society for Testing and Materials. 2003 Annual Book of ASTM Standards. Standard Specification and Test Method for Metallic Bone Plates, ASTM F382\u201399 (Reapproved 2003). West Conshohocken, PA: ASTM."},{"key":"pone.0295526.ref018","doi-asserted-by":"crossref","first-page":"1256","DOI":"10.1016\/j.injury.2010.05.007","article-title":"Treatment of periprosthetic femoral fractures with two different minimal invasive angle-stable plates: Biomechanical comparison studies on cadaveric bones","volume":"41","author":"L Konstantinidis","year":"2010","journal-title":"Injury"},{"key":"pone.0295526.ref019","doi-asserted-by":"crossref","first-page":"369","DOI":"10.1186\/1471-2474-15-369","article-title":"Mono- versus polyaxial locking plates in distal femur fractures\u2013a biomechanical comparison of the Non-Contact-Bridging- (NCB) and the PERILOC-plate","volume":"15","author":"BF El-Zayat","year":"2014","journal-title":"BMC Musculoskelet Disord"},{"key":"pone.0295526.ref020","doi-asserted-by":"crossref","first-page":"830","DOI":"10.1097\/01.ta.0000195462.53525.0c","article-title":"Fixation of Diaphyseal Fractures with a Segmental Defect: A Biomechanical Comparison of Locked and Conventional Plating Techniques","volume":"60","author":"E Fulkerson","year":"2006","journal-title":"The Journal of Trauma: Injury, Infection, and Critical Care"},{"key":"pone.0295526.ref021","doi-asserted-by":"crossref","first-page":"e7","DOI":"10.1097\/BOT.0000000000000391","article-title":"Early Mechanical Failures of the Synthes Variable Angle Locking Distal Femur Plate","volume":"30","author":"JC Tank","year":"2016","journal-title":"J Orthop Trauma"},{"key":"pone.0295526.ref022","doi-asserted-by":"crossref","first-page":"857","DOI":"10.1007\/s00264-013-2210-0","article-title":"Mono- versus polyaxial locking plates in distal femur fractures: a prospective randomized multicentre clinical trial","volume":"38","author":"M Hanschen","year":"2014","journal-title":"Int Orthop"},{"key":"pone.0295526.ref023","doi-asserted-by":"crossref","first-page":"105645","DOI":"10.1016\/j.jmbbm.2022.105645","article-title":"Failure analysis of a locking compression plate with asymmetric holes and polyaxial screws","volume":"138","author":"N-Z Zhang","year":"2023","journal-title":"J Mech Behav Biomed Mater"},{"key":"pone.0295526.ref024","doi-asserted-by":"crossref","first-page":"1624","DOI":"10.1016\/j.injury.2016.06.001","article-title":"The biomechanical cost of variable angle locking screws","volume":"47","author":"JE Tidwell","year":"2016","journal-title":"Injury"},{"key":"pone.0295526.ref025","doi-asserted-by":"crossref","first-page":"637","DOI":"10.1016\/j.clinbiomech.2009.06.004","article-title":"The strength of polyaxial locking interfaces of distal radius plates","volume":"24","author":"KL Hoffmeier","year":"2009","journal-title":"Clinical Biomechanics"}],"container-title":["PLOS ONE"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0295526","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,12,11]],"date-time":"2023-12-11T18:24:08Z","timestamp":1702319048000},"score":1,"resource":{"primary":{"URL":"https:\/\/dx.plos.org\/10.1371\/journal.pone.0295526"}},"subtitle":[],"editor":[{"given":"Pawel","family":"Klosowski","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"editor"}]}],"short-title":[],"issued":{"date-parts":[[2023,12,11]]},"references-count":25,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2023,12,11]]}},"URL":"https:\/\/doi.org\/10.1371\/journal.pone.0295526","relation":{},"ISSN":["1932-6203"],"issn-type":[{"value":"1932-6203","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,12,11]]}}}