Beaks and peaks in adult skeleton, Part I: Bony excrescences in skull base and upper extremity

Abstract

Bony protrusions which may be part of normal or variant anatomy or de novo pathologic conditions can have particular imaging and clinical findings. They can arise as a result of overuse injuries and trauma. Additionally, some bony spurs may have an evolutionary base. Some of them can result from a previous injury whereas some others are the reason for the injury of neighbouring structures themselves. Presenting symptoms may also vary accordingly, from being asymptomatic, where the lesions are detected incidentally, to being associated with severe pain and limited range of motion due to impingement and mass effect on the surrounding tissues. The purpose of this pictorial review is to overview some common and some infrequent but important bony excrescences, by emphasising on their clinical importance and differential diagnoses based on their imaging findings. This first part of the review covers the skull base and upper extremity with emphasis on the latter.