Locked facet joint is a type of facet joint dislocation that results from jumping of the inferior articular process over the superior articular process of the vertebra below and becomes locked in the position.
It can be unilateral or bilateral.
The tip of the inferior articular process is seen anterior to the superior articular process of the vertebra below.
Shows the radiographic findings in more details. The naked facet sign (a.k.a. reverse hamburger bun sign) sometimes can be seen on an axial scan.
Can show ligamentous injuries apart from the dislocation.
- 1. O'Shaughnessy J, Grenier JM, Stern PJ. A delayed diagnosis of bilateral facet dislocation of the cervical spine: a case report. J Can Chiropr Assoc. 2014;58 (1): 45-51. Free text at pubmed - Pubmed citation
- 2. Piccirilli M, Liberati C, Santoro G et-al. Cervical Post-traumatic Unilateral Locked Facets: Clinical, Radiological and Surgical Remarks on a Series of 33 Patients. J Spinal Disord Tech. 2015; . doi:10.1097/BSD.0b013e3182870c3f - Pubmed citation
- 3. Sim E, Schwarz N. Unilateral locking of cervical facet joints. Frequency and value of roentgenologic signs. Unfallchirurg. 1993;96 (10): 551-5. Pubmed citation
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