Occipital spur: an incidental finding on a diagnostic cone-beam computed tomography – a case report

Abstract

Exaggerated bony outgrowth of the external occipital protuberance is called occipital spur. The current report presents a case of a 20-year-old male patient seeking orthodontic treatment. The patient was referred for a cone-beam computed tomography scan to determine the position of impacted maxillary canines. An incidental finding on the scan was the existence of a focal spine-like hyperostosis in the occipital protuberance, and confirmed to be an occipital spur (Type III spine form). Clinical examination showed a palpable bone swelling without any tenderness, infection or discharge. He was referred to an orthopaedic surgeon should any symptoms get aggravated in the future. This case supports the essential role of cone-beam computed tomography to detect, analyse and identify the lesion as an occipital spur. This is the first such case report of its kind, which measures the size of occipital spur using cone-beam computed tomography and 3D imaging software. Usually asymptomatic, awareness of this uncommon presentation can expedite emergency medical care in the event of pain, or trauma leading to fracture or avulsion of the spur fragment. In such an event, the readily available CBCT data will be indispensable to surgeons for planning surgery with precise linear and volumetric measurements. Knowledge of these bony spurs is of untold value to anatomists, who will benefit greatly from being able to study the variants in vivo, in addition to studies on dry skulls or preserved cadavers. It is also of interest to clinicians and radiologists for diagnostic purposes, and sports physicians.

Keywords

• Cone-beam computed tomography (CBCT)
• external occipital protuberance
• inion hook
• occipital spur

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