The myloglossus in a human cadaver study: common or uncommon anatomical structure?
Abstract
Background: Additional extrinsic muscles of the tongue are reported in literature and one of them is the myloglossus muscle (MGM). Since MGM is nowadays considered as anatomical variant, the aim of this study is to clarify some open questions by evaluating and describing the myloglossal anatomy (including both MGM and its ligamentous counterpart) during human cadaver dissections.
Materials and methods: Twenty-one regions (including masticator space, sublingual space and adjacent areas) were dissected and the presence and appearance of myloglossus were considered, together with its proximal and distal insertions, vascularisation and innervation.
Results: The myloglossus was present in 61.9% of cases with muscular, ligamentous or mixed appearance and either bony or muscular insertion. Facial artery provided myloglossal vascularisation in the 84.62% and lingual artery in the 15.38%; innervation was granted by the trigeminal system (buccal nerve and mylohyoid nerve), sometimes (46.15%) with hypoglossal component.
Conclusions: These data suggest us to not consider myloglossus as a rare anatomical variant.
Keywords: anatomical variantdissectionmyloglossustongue
References
- Barnwell YM. The morphology of musculus styloglossus in fifteen-week human fetuses. Int J Oral Myol. 1977; 3(2): 8–46.
- Bonamy C, Broca P, Beau ME (1866) Atlas d’anatomie descriptive du corps humain. Masson, Paris.
- Dunglison R. A new dictionary of medical sciences. Charles Bowen, Boston, 1833.
- Gruber W. Ueber den musculeus myloglossus bei mangel und vorkommen des M. styloglossus. Arch Pathol Anat Physiol Klin Med. 1980; 81: 453–457.
- Hallett CH. An account of the varieties of the muscular system met with in the dissecting room of the University of Edinburgh during the winter session 1847–1848. Edinb Med Surg J. 1849; 22: 1–6.
- Katori Y, Yamamoto M, Asakawa S, et al. Fetal developmental change in topographical relationship between the human lateral pterygoid muscle and buccal nerve. J Anat. 2012; 220(4): 384–395.
- Kim HJ, Kwak HH, Hu KS, et al. Topographic anatomy of the mandibular nerve branches distributed on the two heads of the lateral pterygoid. Int J Oral Maxillofac Surg. 2003; 32(4): 408–413.
- Lang J, Jüde HD. [Anatomy of the retromolar region of the human mandible]. Anat Anz. 1973; 133(3): 276–282.
- Macalister A. The Varieties of the Styloid Muscles. J Anat Physiol. 1870; 5(Pt 1): 28–31.
- Macalister A. Additional observations on muscular anomalies in human anatomy (third series) with a catalogue of the principal muscular variations hitherto published. Trans R Irish Acad, Dublin, 1875.
- Mérida-Velasco JR, Rodríguez-Vazquez JF, de la Cuadra Blanco C, et al. Origin of the styloglossus muscle in the human fetus. J Anat. 2006; 208(5): 649–653.
- Micheli-Pellegrini V. About muscle insertions in man (Proposal for a new nomenclature of striated muscle). Acta Otorhinolaryngol Ital. 2011; 31(3): 167–176.
- Nakajima K, Nakamura M. Rare case of myloglossus in Japanese cadaver: anatomical and developmental considerations. Anat Sci Int. 2008; 83(1): 1–5.
- Rodella LF, Buffoli B, Boninsegna R, et al. The myloglossus muscle: anatomical and clinical observations. Italian J Anat Embryol. 2011; 116: 154.
- Rodella LF, Buffoli B, Labanca M, et al. A review of the mandibular and maxillary nerve supplies and their clinical relevance. Arch Oral Biol. 2012; 57(4): 323–334.
- Rood SR, Langdon H, Klueber K, et al. Muscular anatomy of the tonsil and tonsillar bed: a reexamination. Otolaryngol Head Neck Surg. 1979; 87(4): 401–408.
- Standring S. Gray’s anatomy. 40th Ed. Elsevier, London, 2009.
- Valenti G. Sur un muscle mandibulo-glosse (M. myloglossus Wood). Arch Ital Biol. 1926; 75: 77.
- Wood J. Variations in Human Myology Observed during the Winter Session of 1866-67 at King's College, London. Proceedings of the Royal Society of London. 1866; 15(0): 518–546.
