{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T09:12:42Z","timestamp":1760001162888,"version":"build-2065373602"},"reference-count":51,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2025,10,5]],"date-time":"2025-10-05T00:00:00Z","timestamp":1759622400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JFMK"],"abstract":"<jats:p>Introduction: Neck-preserving total hip arthroplasty (THA) has gained interest for conserving bone stock, restoring biomechanics, and facilitating revision surgery. The Nanos\u00ae femoral stem, designed for metaphyseal fixation while preserving the femoral neck, represents a reliable alternative to conventional THA. This study reports 15-year clinical and radiographic outcomes of the Nanos implant. Materials and Methods: We retrospectively reviewed 53 patients (35 males, 18 females) who underwent THA with the Nanos stem between 2008 and 2010. Patients were stratified into two groups according to age: &lt;50 years (n = 24) and \u226550 years (n = 29). The primary diagnosis was osteoarthritis (95%), with a few cases of avascular necrosis or dysplasia. Clinical evaluation included the Harris Hip Score (HHS) and the Western Ontario and McMaster Universities Arthritis Index (WOMAC). Radiographic assessment focused on implant stability, osteolysis, and heterotopic ossifications. Kaplan\u2013Meier survival analysis was performed with revision for any reason as the endpoint. Results: At 15 years of follow-up, both groups showed significant improvement (p &lt; 0.001). In patients &lt;50 years, HHS increased from 53.3 to 94.8 and WOMAC decreased from 79.9 to 3.5. In patients \u226550 years, HHS improved from 47.5 to 95.2 and WOMAC from 81.5 to 3.2. Radiographs confirmed stable fixation without osteolysis. Complications included two dislocations and one cortical perforation requiring revision. Kaplan\u2013Meier survivorship at 15 years was 100% (&lt;50) and 96.6% (\u226550). Conclusions: The Nanos stem provided excellent long-term outcomes with low complication and revision rates. It should be considered one of several reliable short-stem options for younger, active patients, offering durable function while preserving bone stock.<\/jats:p>","DOI":"10.3390\/jfmk10040389","type":"journal-article","created":{"date-parts":[[2025,10,6]],"date-time":"2025-10-06T13:33:41Z","timestamp":1759757621000},"page":"389","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Fifteen-Year Follow-Up of Nanos Neck-Preserving Hip Arthroplasty: An Observational Retrospective Study"],"prefix":"10.3390","volume":"10","author":[{"given":"Giuseppe","family":"Rovere","sequence":"first","affiliation":[{"name":"Section of Orthopaedics and Traumatology, Department of Clinical Science and Translational Medicine, University of Rome \u201cTor Vergata\u201d, 00133 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Davide","family":"Luziatelli","sequence":"additional","affiliation":[{"name":"Section of Orthopaedics and Traumatology, Department of Clinical Science and Translational Medicine, University of Rome \u201cTor Vergata\u201d, 00133 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sandro","family":"Luziatelli","sequence":"additional","affiliation":[{"name":"Villa Letizia, Strada Statale 80, 25\/b, 67100 L\u2019Aquila, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Gianluca","family":"Polce","sequence":"additional","affiliation":[{"name":"Orthopaedics and Traumatology Unit, Celio Military Hospital, 00100 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pierfrancesco","family":"Pirri","sequence":"additional","affiliation":[{"name":"Section of Orthopaedics and Traumatology, Department of Clinical Science and Translational Medicine, University of Rome \u201cTor Vergata\u201d, 00133 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Vincenzo","family":"De Luna","sequence":"additional","affiliation":[{"name":"Section of Orthopaedics and Traumatology, Department of Clinical Science and Translational Medicine, University of Rome \u201cTor Vergata\u201d, 00133 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3602-8155","authenticated-orcid":false,"given":"Francesco","family":"Liuzza","sequence":"additional","affiliation":[{"name":"Section of Orthopaedics and Traumatology, Department of Clinical Science and Translational Medicine, University of Rome \u201cTor Vergata\u201d, 00133 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7460-282X","authenticated-orcid":false,"given":"Pasquale","family":"Farsetti","sequence":"additional","affiliation":[{"name":"Section of Orthopaedics and Traumatology, Department of Clinical Science and Translational Medicine, University of Rome \u201cTor Vergata\u201d, 00133 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5201-6755","authenticated-orcid":false,"given":"Fernando","family":"De Maio","sequence":"additional","affiliation":[{"name":"Section of Orthopaedics and Traumatology, Department of Clinical Science and Translational Medicine, University of Rome \u201cTor Vergata\u201d, 00133 Rome, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,10,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"36","DOI":"10.1007\/s10195-006-0120-2","article-title":"Tissue-sparing surgery: 25 years\u2019 experience with femoral neck-preserving hip arthroplasty","volume":"7","author":"Pipino","year":"2006","journal-title":"J. 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