Incidence of 99Tc-MDP uptake in the external occipital protuberance in the pediatric population: the new normal?

Children and young adults have a vast array of electronics at their fingertips. While it can provide endless hours of entertainment and education, we are also seeing a structural consequence. Children are using these devices with their head tilted down with poor posture resulting in increased stress on the skull from attached structures which can lead to a bone spur (exostosis) at the external occipital protuberance (EOP). While typically painless, it can progress to necessitate surgical intervention.

The purpose of this study is to understand the prevalence of exostosis at the EOP and how the finding can affect the nuclear medicine bone scan.

43 pediatric patients who underwent a whole-body bone scan over a period of 1 year were included in the study (10-19 years old). Images were reviewed by 2 board-certified Nuclear Medicine physicians to assess for uptake midline in the occipital skull. Suspected cases were followed up with all available clinical and radiographic reports and images.

Bone scan demonstrated an occipital focus of uptake in 7 (16%) of the 43 patients (5 males and 2 females with a mean age of 15 years; range 10-19). Of these, 5/7 (71%) were confirmed by additional imaging.

The rapidly advancing technology is leading to increased screen time in children and young adults. Our study shows that 16% of the pediatric population imaged at our facility between the ages of 10-19 years have signs of exostosis at the EOP. It is particularly important for clinicians to be aware of this entity when reading bone scans to avoid false positive interpretations.