Backus, who's started 160 straight games, suffered a partially-torn chest muscle during the offseason and spent the first three weeks of training camp on the active/non-football injury list.
It's not clear whether he'll play in Saturday's exhibition game against visiting New England.
"Physically, I just have to get back the timing," he said. "The rest of these guys have three weeks on me. I've just got to play a little catch-up."
The 2001 first-round draft pick said the injury kept him from the full use of his left arm for a few weeks. Coach Jim Schwartz wouldn't say if he'll use Backus on Saturday but the lineman said he'll approach this week as if he is going to play.
Backus' return completes the Lions' regular starting offensive line from last season.
Jahvid Best left Friday's exhibition game after being hit on the Lions' third offensive play and was removed from the game after complaining of a headache. Schwartz said the second-year tailback felt better a day later.
"By the next day he was clearing up," the coach said. "We'll be very cautious with him but we should have him back on the practice field pretty soon."
Losing Best for an extended period would have further depleted a group of backs that already lost rookie Mikel Leshoure to a season-ending injury and still is waiting for Maurice Morris to return from a hand injury.
Best led the Lions with 555 yards on the ground and had 487 more as a receiver last year. Morris, who added 336 yards and scored five touchdowns last season, took part in some drills Sunday and his status for Saturday's game is uncertain.
Rookie receiver Titus Young (muscle tightness) participated in seven-on-seven drills during Sunday's practice and Schwartz said the team hopes to have him participating fully soon.