Banks (knee) has been ruled out of Sunday's game against the Dolphins, Nick Wagoner of ESPN.com reports.
Banks went down with a knee injury in the second half, which will sideline him at least until next Monday's Week 17 game versus the Lions. The starting left guard is joined by left tackle Jaylon Moore (quad) on the sideline, so Spencer Burford and Nick Zakelj are now on the offensive line for the 49ers.