This is Ask an Expert. Every weekday at 9:20 a.m. on KCBS, we give you direct access to top experts in various fields.
Today is the first day of the NFL preseason. But past the highlights and Hall of Fame debates, the x-rays tell a troubling story about the most popular sport in America.
For more, KCBS' Steve Scott spoke with Dr. Andy Josephson, neurologist at UCSF and Dean of the UCSF School of Medicine.
