{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,6]],"date-time":"2026-01-06T05:25:51Z","timestamp":1767677151591,"version":"build-2065373602"},"reference-count":36,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2024,5,22]],"date-time":"2024-05-22T00:00:00Z","timestamp":1716336000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"AO Foundation"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Medicina"],"abstract":"<jats:p>Background and Objectives: Despite the established role of subtalar joint arthrodesis (SJA) for treatment of subtalar osteoarthritis, achieving bone union remains challenging, with up to 46% non-union rates. Adequate compression and stable fixation are crucial for successful outcomes, with internal screw fixation being the gold standard for SJA. The delta configuration, featuring highly divergent screws, offers stability, however, it can result in hardware irritation in 20\u201330% of patients. Solutions to solve this complication include cannulated compression screw (CCS) countersinking or cannulated compression headless screw (CCHS) application. The aim of this biomechanical study was to investigate the stability of a delta configuration for SJA utilizing either a combination of a posterior CCHS and an anterior CCS or a standard two-CCS combination. Materials and Methods: Twelve paired human cadaveric lower legs were assigned pairwise to two groups for SJA using either two CCSs (Group 1) or one posterior CCHS and one anterior CCS (Group 2). All specimens were tested under progressively increasing cyclic loading to failure, with monitoring of the talocalcaneal movements via motion tracking. Results: Initial stiffness did not differ significantly between the groups, p = 0.949. Talocalcaneal movements in terms of varus\u2013valgus deformation and internal\u2013external rotation were significantly bigger in Group 1 versus Group 2, p \u2264 0.026. Number of cycles until reaching 5\u00b0 varus\u2013valgus deformation was significantly higher in Group 2 versus Group 1, p = 0.029. Conclusions: A delta-configuration SJA utilizing a posterior CCHS and an anterior CCS is biomechanically superior versus a standard configuration with two CCSs. Clinically, the use of a posterior CCHS could prevent protrusion of the hardware in the heel, while an anterior CCS could facilitate less surgical time and thus less complication rates.<\/jats:p>","DOI":"10.3390\/medicina60060844","type":"journal-article","created":{"date-parts":[[2024,5,22]],"date-time":"2024-05-22T11:03:47Z","timestamp":1716375827000},"page":"844","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Optimizing Subtalar Arthrodesis: A Human Cadaveric Evaluation of a Novel Partially-Threaded Screw Combination in the Delta Configuration"],"prefix":"10.3390","volume":"60","author":[{"given":"Georgi","family":"Raykov","sequence":"first","affiliation":[{"name":"AO Research Institute Davos, 7270 Davos, Switzerland"},{"name":"Department of Surgery, Cantonal Hospital of Uri, 6460 Altdorf, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Stoyan","family":"Ivanov","sequence":"additional","affiliation":[{"name":"AO Research Institute Davos, 7270 Davos, Switzerland"},{"name":"Department of Orthopedics and Traumatology, Saint Marina Regional Hospital, Medical University Varna, 9002 Varna, Bulgaria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9795-115X","authenticated-orcid":false,"given":"Boyko","family":"Gueorguiev","sequence":"additional","affiliation":[{"name":"AO Research Institute Davos, 7270 Davos, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tatjana","family":"Pastor","sequence":"additional","affiliation":[{"name":"AO Research Institute Davos, 7270 Davos, Switzerland"},{"name":"Department of Plastic and Hand Surgery, Inselspital University Hospital Bern, University of Bern, 3007 Bern, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Till","family":"Berk","sequence":"additional","affiliation":[{"name":"AO Research Institute Davos, 7270 Davos, Switzerland"},{"name":"Department of Orthopedics, Traumatology and Reconstructive Surgery, University Hospital Aachen, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4357-236X","authenticated-orcid":false,"given":"Torsten","family":"Pastor","sequence":"additional","affiliation":[{"name":"AO Research Institute Davos, 7270 Davos, Switzerland"},{"name":"Department of Orthopedics and Traumatology, Luzern Regional Hospital, 6110 Wolhusen, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0484-887X","authenticated-orcid":false,"given":"Ivan","family":"Zderic","sequence":"additional","affiliation":[{"name":"AO Research Institute Davos, 7270 Davos, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"293","DOI":"10.1016\/j.fcl.2015.02.002","article-title":"The Spectrum of Indications for Subtalar Joint Arthrodesis","volume":"20","author":"Vulcano","year":"2015","journal-title":"Foot Ankle Clin."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"419","DOI":"10.1177\/1071100715619680","article-title":"Biomechanical Evaluation of Strength and Stiffness of Subtalar Joint Arthrodesis Screw Constructs","volume":"37","author":"Jastifer","year":"2016","journal-title":"Foot Ankle Int."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"774","DOI":"10.1177\/107110070402501103","article-title":"Subtalar Joint Arthrodesis Using a Single Lag Screw","volume":"25","author":"Haskell","year":"2004","journal-title":"Foot Ankle Int."},{"doi-asserted-by":"crossref","unstructured":"Perisano, C., Cannella, A., Polichetti, C., Mascio, A., Comisi, C., De Santis, V., Caravelli, S., Mosca, M., Spedicato, G.A., and Maccauro, G. 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