Surg Radiol Anat (2010) 32:513–517 DOI 10.1007/s00276-009-0553-4 123 ANATOMIC VARIATIONS An unreported anatomical Wnding: unusual insertions of the stylohyoid and digastric muscles Zuhal Ozgur · Figen Govsa · Servet Celik · Tomris Ozgur Received: 5 June 2008 / Accepted: 27 August 2009 / Published online: 11 September 2009  Springer-Verlag 2009 Abstract The presence of a unusual appearance of the stylohyoid and digastric muscles may lead to a confusion in some pathological cases, during the radiological exami- nation and aesthetic facial surgery. These diVerences may cause pharyngeal pain and foreign body sensation in the throat. During the dissection, unusual insertions, origin, insertion, shape and bilaterality were investigated in 28 cadavers’ heads. In a total of 56, the presence of unusual insertions which belong to the stylohyoid muscle were observed in 22 sides (39.3%), and atypical Wbers which belong to the digastric muscle were observed in 39 sides (69.6%). Bilaterality of the presence of atypical appear- ance was observed for stylohyoid and digastric muscles, in 10 (35.7%) and 19 (67.8%) specimens, respectively. In 12 heads (42.9%), atypical Wbers, the stylohyoid and the digastric coexisted. These Wbers which were shaped like a circular spiral were realized to have the shape of an arch or circle in front of the hyoid bone. The posterior bellies of the digastric muscle, the mylohyoid and the remaining suprahyoid muscles of both sides were normal. The unusual insertion of the stylohyoid muscles which cover the hyoid bone as a collar was not described in the classiW- cation of the previous studies. These Wbers may give an variant mobility to the hyoid and they occur depending on the diVerences in the stylohyoid chains. Although the styloid process was in normal size, unusual insertions of the stylohyoid muscle that cover the hyoid as a belt or collar may give symptoms similar to those of the stylohyoid syndrome. Keywords Stylohyoid muscle · Digastric muscle · Unusual insertions · Stylohyoid syndrome · Pain Introduction The styloid process (SP) is a long cylindrical cartilaginous bone. Three muscles (stylopharyngeus, stylohyoid, and styloglosus) and two ligaments (stylohyoid and styloman- dibular) are attached to the SP [1–5, 20]. The “standard” reported length of the SP ranges from 20 to 32 mm [2, 3, 6, 8, 12]. The SP lies between the internal and external carotid arteries and is in close vicinity with important structures. Laterally, the facial and the hypoglossal nerves, the occipi- tal artery, and the posterior belly of the digastric muscle are found [2, 3, 6, 8, 12]. Medially, the lingual, facial, superW- cial temporal, maxillary, internal carotid arteries, as well as the internal jugular vein, and the sphenomandibular liga- ment are present [2, 3, 6, 8, 12]. The variations of the SP and its related structures, such as ram’s horn, elongated, segmented, jointlike, pseudoartic- ulated, jointed, crooked and nodular, bent, and partial ossiWcation were reported by several authors [7, 18, 22]. Elongation of the styloid process and ossiWcation of the sty- lohyoid ligament is named as The Eagle Syndrome and it causes neck and pharyngeal pain, otalgia, and foreign body sensation in the throat [1, 11, 14, 15]. Z. Ozgur Ataturk Medical Technology Vocational School, Ege University, Izmir, Turkey F. Govsa · S. Celik · T. Ozgur Department of Anatomy, Faculty of Medicine, Ege University, Izmir, Turkey F. Govsa (&) Ege Universitesi Tip Fakultesi Anatomi Anabilim Dali, 35100 Izmir, Turkey e-mail: figen.govsa@ege.edu.tr; fgovsa@yahoo.com