{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,5]],"date-time":"2026-10-05T17:59:07Z","timestamp":1791223147287,"version":"4.1.0"},"reference-count":70,"publisher":"Ovid Technologies (Wolters Kluwer Health)","issue":"20","license":[{"start":{"date-parts":[[2024,9,16]],"date-time":"2024-09-16T00:00:00Z","timestamp":1726444800000},"content-version":"unspecified","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["lww.com","ovid.com"],"crossmark-restriction":true},"short-container-title":[],"published-print":{"date-parts":[[2024,10,16]]},"abstract":"<jats:p>\n                    <jats:list list-type=\"plain\">\n                      <jats:list-item>\n                        <jats:p>\u27a2 The alpha angle was originally defined on magnetic resonance imaging (MRI) scans, using a plane, parallel to the axis of the femoral neck. However, much of the literature on the alpha angle has used radiographs or other imaging modalities to quantify the alpha angle.<\/jats:p>\n                      <\/jats:list-item>\n                      <jats:list-item>\n                        <jats:p>\u27a2 The measurement of the alpha angle can be unreliable, particularly on radiographs and ultrasound.<\/jats:p>\n                      <\/jats:list-item>\n                      <jats:list-item>\n                        <jats:p>\u27a2 If radiographs are used to measure the alpha angle, the circle of best-fit method should be used on multiple different views to capture various locations of the cam lesion, and \u201ceyeballing\u201d or estimating the alpha angle should be avoided.<\/jats:p>\n                      <\/jats:list-item>\n                      <jats:list-item>\n                        <jats:p>\u27a2 The cam lesion is a dynamic and 3-dimensional (3D) problem and is unlikely to be adequately defined or captured by a single angle.<\/jats:p>\n                      <\/jats:list-item>\n                      <jats:list-item>\n                        <jats:p>\u27a2 Modern technology, including readily available 3D imaging modalities, as well as intraoperative and dynamic imaging options, provides novel, and potentially more clinically relevant, ways to quantify the alpha angle.<\/jats:p>\n                      <\/jats:list-item>\n                    <\/jats:list>\n                  <\/jats:p>","DOI":"10.2106\/jbjs.23.01089","type":"journal-article","created":{"date-parts":[[2024,9,16]],"date-time":"2024-09-16T14:45:07Z","timestamp":1726497907000},"page":"1910-1921","update-policy":"https:\/\/doi.org\/10.1097\/lww.0000000000001000","source":"Crossref","is-referenced-by-count":11,"title":["The Alpha 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Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9454-3978","authenticated-orcid":false,"given":"Vikas","family":"Khanduja","sequence":"additional","affiliation":[{"name":"School of Clinical Medicine, University of Cambridge, Cambridge, United Kingdom"},{"name":"Young Adult Hip Service, Department of Trauma and Orthopaedics, Addenbrooke\u2019s Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"276","published-online":{"date-parts":[[2024,9,16]]},"reference":[{"issue":"2","key":"bib1-20250430","doi-asserted-by":"crossref","first-page":"264","DOI":"10.1007\/s11999-007-0060-z","article-title":"The etiology of osteoarthritis of the hip: an integrated mechanical concept","volume":"466","author":"Ganz","year":"2008","journal-title":"Clin Orthop Relat 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