Massively Enlarged and Completely Ossified Stylohyoid Chain with Associated Neck Pain

Abstract

Multiple radiologic and anatomic studies have shown variable ossification of the stylohyoid chain. There have been varied reports about increasing ossification with advancing age. Proximal ossification can be seen early in life while distal ossification towards the hyoid bone is more characteristic of advancing age. Abnormality is assumed when the total length of the stylohyoid process and stylohyoid ligament show an overall length of greater than 25 mm. Removal of the stylohyoid chain for pain related symptoms was first report in 1872. Pathological states can be evaluated as abnormal length of the stylohyoid bone and ossification of the styloyoid ligament, that latter which typically presents as pain when moving. Steinman proposed three theories for abnormal ossification. The “Theory of Reactive Hyperplasia” proposes trauma induces ossification in the post traumatic period (i.e. tonsillectomy). The “Theory of Reactive Hyperplasia” suggests traumatic events cause metaplastic changes throughout the stylohyoid ligament leading to ossification. The “Theory of Anatomic Variance” suggests ossification is a normal variant of development, explaining the early ossification prior to 20 years of age. The “Theory of Aging Developmental Anomaly” adds to this later theory by suggesting loss of elasticity in the stylohyoid ligament in advance age then leads to symptomatic complaints. Herein, we discuss the clinical presentation, radiographic evaluation, and management of a 62-year-old female presenting with neck pain with a histologically confirmed complete ossification of the stylohyoid ligament. We also review anatomical variations of the stylohyoid chain and potential associated symptoms. Introduction