There isn’t much known about what causes ES, so any information in that regard is welcome. Sometimes trauma can cause it but other things can too.
Here’s a recent (this year!) case report highlighting an unusual potential cause of Eagle syndrome, namely radiation therapy for cancers.
Eagle Syndrome Secondary to Osteoradionecrosis of the Styloid Process
A man received radiation therapy for a tumor in his tonsil. The styloid process happened to be in the irradiated area. Several months after completing therapy, he developed typical ES symptoms: “right-sided jaw pain, trismus [lockjaw], intermittent right-sided otalgia, dysphagia, and feelings of warmth and redness over his right parotid region.”
A CT scan showed that his styloid was fragmented at the tip and was pressing into his throat. The man underwent intraoral surgery, the surgeon removed a 2-cm piece of necrotic styloid, and the man’s symptoms went away.
The authors theorize the radiation therapy caused bone death (“osteoradionecrosis”) in the styloid process, which led to ES. They indicate that patients who undergo radiotherapy for head or neck cancer are potentially at risk for ES.
In my opinion, like with all forms of ES, radiation-induced ES is probably more common than doctors think, it’s just under-diagnosed because the doctors never look for it.
I hope this information can help people who come to this site.