49ers' Marcus Lattimore retires after comeback from injury stalls

Thursday's health and safety news from the world of football:

• NFL.com reported that 49ers running back Marcus Lattimore has decided to retire after he tried for two years to come back from a horrific knee injury while playing at South Carolina.

• former NFL running back Herschel Walker, who talked to troops at Travis Air Force Base about dealing with mental illness.

• The Philadelphia Eagles' official website featured the team's cheerleaders, who have been nominated for the Salute To Service Award.

• that Fox Sports will air part of its NFL pre-game show on Sunday from Fort Benning.

• ESPN profiled Anna Isaacson, who was chosen to become the NFL's vice president of social responsibility.

• The Boston Globe featured the Boston Brawlers of the FXFL, whose players are hoping for one more shot at the NFL.

• NPR reported on the sideline video robot used by Dartmouth to connect neurologists to the football team.

• KGNS-TV in Laredo, Texas, examined the helmets being used by local high schools and whether they meet the standards of the Virginia Tech STAR ratings.

• The Associated Press reported that the University of Arkansas will bring together representatives from many colleges for a concussion summit next week.

• The Atlantic looked at early plastic football helmets and how they often cracked on impact.

• WBNS-TV in Columbus, Ohio, talked to high school officials who are concerned that sports specialization can lead to more injuries.

-- Bill Bradley, contributing editor