{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,10]],"date-time":"2026-02-10T20:18:17Z","timestamp":1770754697727,"version":"3.50.0"},"reference-count":35,"publisher":"BMJ","issue":"2","content-domain":{"domain":["bmj.com"],"crossmark-restriction":true},"short-container-title":["BMJ Case Rep"],"accepted":{"date-parts":[[2026,1,30]]},"published-print":{"date-parts":[[2026,2]]},"abstract":"<jats:p>Traumatic atlantoaxial instability resulting from an isolated ligament injury is exceptionally rare in adults. Isolated alar ligament ruptures have only been reported sporadically in the literature. These injuries are often misdiagnosed or overlooked, which can lead to delayed recognition and serious consequences for the patient\u2019s health and quality of life.<\/jats:p>\n                  <jats:p>We report the case of a previously healthy male professional ice hockey player who sustained a unilateral rupture of the left alar ligament accompanied by minor atlantoaxial facet joint dissociation following a high-speed collision during a tournament. The injury was managed conservatively with 12\u2009weeks of rigid cervical spine immobilisation, multimodal analgesia and follow-up radiographic assessment 12\u2009weeks after the injury.<\/jats:p>\n                  <jats:p>The patient made a full recovery and returned to competitive sports 5\u2009months after the injury with no residual symptoms or functional limitations.<\/jats:p>","DOI":"10.1136\/bcr-2025-268016","type":"journal-article","created":{"date-parts":[[2026,2,10]],"date-time":"2026-02-10T15:24:45Z","timestamp":1770737085000},"page":"e268016","update-policy":"https:\/\/doi.org\/10.1136\/crossmarkpolicy","source":"Crossref","is-referenced-by-count":0,"title":["Do-not-miss-injury: conservative treatment of traumatic ligamentous atlantoaxial instability with unilateral rupture of the alar ligament and minor facet joint dissociation C1\/C2"],"prefix":"10.1136","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-9628-511X","authenticated-orcid":false,"given":"Tobias Peter","family":"Bayer","sequence":"first","affiliation":[{"name":"Trauma Surgery, University Hospital Zurich, Z\u00fcrich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Thylane Elli","family":"Vancastell","sequence":"additional","affiliation":[{"name":"Emergency Medicine, University Hospital Zurich, Z\u00fcrich, Switzerland"},{"name":"Addenbrooke\u2019s Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge, England, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hans-Christoph","family":"Pape","sequence":"additional","affiliation":[{"name":"Trauma Surgery, University Hospital Zurich, Z\u00fcrich, Switzerland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Klaus J","family":"Schnake","sequence":"additional","affiliation":[{"name":"Center for Spinal and Scoliosis Surgery, Malteser Waldkrankenhaus St Marien gGmbH, Erlangen, BY, Germany"},{"name":"Clinic for Orthopedics and Trauma Surgery, University Hospital of the Paracelsus Medical Private University Nuremberg, Nuremberg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"239","published-online":{"date-parts":[[2026,2,10]]},"reference":[{"key":"2026021007060390000_19.2.e268016.1","unstructured":"Lacy J , Bajaj J , Gillis CC . 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