SANTA CLARA -- Aaron Lynch on Wednesday practiced in full for the first time since a Dec. 6 concussion, but his outside linebacker counterpart, Ahmad Brooks, missed practice with shoulder and back issues. Lynch’s 6 1/2 sacks this season lead the 49ers.
Also missing practice was offensive lineman Marcus Martin, who suffered a concussion in the third quarter of Sunday's game. That increases the chances that Erik Pears will start against the Lions at right guard and that rookie Trent Brown will make his first-ever NFL start at right tackle.
Guard Alex Boone (knee), running back Shaun Draughn (knee), receiver Torrey Smith (back, toe) and linebacker Michael Wilhoite (ankle) also missed practice. If Draughn can’t play, Kendall Gaskins and newcomer DuJuan Harris would be the 49ers’ only healthy running backs in Detroit.
Did not participate: G Alex Boone (knee), LB Navorro Bowman (shoulder, finger), LB Ahmad Brooks (shoulder, back), RB Shaun Draughn (knee), C Marcus Martin (concussion), WR Torrey Smith (back, foot), LB Michael Wilhoite (ankle)
Limited participation: DT Quinton Dial (shoulder), CB Dontae Johnson (ankle), T Joe Staley (knee)
Full participation: DT Arik Armstead (shoulder), LB Eli Harold (shoulder, hamstring), LB Aaron Lynch (concussion), T Erik Pears (knee)
Did not participate: S Glover Quin (concussion)
Limited participation: LB Josh Bynes (foot), WR Calvin Johnson (ankle), DT Haloti Ngata (neck), T Michael Ola (knee), DT Caraun Reid (ankle), G Larry Warford (quadricep)