HCR Update from Mark Sanna: The N.F.L. said that the number of concussions in the league had declined 13% this season thanks to improved medical diagnoses, stiffer penalties for striking with a helmet and fewer practices. In the preseason and the regular season, players sustained 228 concussions, down from 261 in 2012, when concussions rose 4% compared with the previous year. Helmet-to-helmet contact caused almost half the concussions this season, down from 53% in 2012.