Eur J Anat, 16 (1): 27-32 (2012)

Ossification of the stylohyoid ligament and â??Eagleâ??sâ?? syndrome

Phillip Naimo¹, Chris Oâ??Donnell², Richard Bassed², Christopher Briggs^1,2

¹Department of Anatomy and Cell Biology, University of Melbourne, Parkville Victoria 3010 ²Victorian Institute of Forensic Medicine, 57-83 Kavanagh Street, Southbank, Victoria 3006

ABSTRACT â??Eagleâ??sâ?? syndrome is a rare condition in which an ossified stylohyoid ligament may endanger neural and vascular structures in the neck (Eagle, 1949, 1962; Rechtweg et al., 1998; Rodriguez-Vazquez et al., 2006; Chuang et al., 2007). Compression of one or other of these structures may give rise to symptoms including unilateral neck pain, dysphagia, otalgia and tinnitus (Kaufman et al., 1970; Omnell et al., 1998; Basekim et al., 2005; Ramadan et al., 2007; Yagci et al., 2007; Ramadan et al., 2010. Computer Tomography (CT) scans of the head and neck of 431 deceased persons (235 males and 196 females) between the ages of 1 day and 100 years (mean age 35.93 ± 24.15) who were admitted for medico-legal death investigation to the Victorian Institute of Forensic Medicine (VIFM) in Melbourne, Australia were examined. Ossification of the ligament was observed to occur in parts, the superior part at its attachment to the styloid process of the temporal bone being the most common. Complete ossification was not seen. Ligament ossification increased with age although there were no sex differences. In some cases there appeared to be a pseudoarthrosis along the course of the ligament. While the study did not examine the anatomical relationship to neurovascular structures it is apparent that the stylohyoid ligament may undergo almost complete ossification and could compress vital neck structures.

Keywords: Stylohyoid ligament, Ossification, Anomalies, Eagle syndrome