I have broken screws at C5 post ACDF. Happened to find them 1 year after ACDF, was having neck pain so I took an xray( I happen to be an xray tech so when we hurt we take our own xrays, CT, MRI....etc not always a good idea) I found the broken screws which NS has never seen them broken in the middle of the bone like mine. He says that it is fine as long as the screws are not backing out. The xray however turned into a CT ordered by my my NS. I am now 4 weeks post op foraminotomy and still am having arm pain and numbness in my thumb.
Broken Screws C5