From Jeremy Reisman, PoD:
All 53 players—yes, including Jarrad Davis, Da’Shawn Hand and Frank Ragnow—were out there participating in warmups. However, in Davis’ and Hand’s case, the two did not appear to be doing much of anything during individual and positional drills. Hand suffered what appeared to be a pretty serious arm injury early in camp, but has since shed the heavy brace on his arm and has clearly made a lot of progress.
Davis went down with what appeared to be a serious ankle injury on the second play of the Lions’ third preseason game. However, he avoided injured reserve, which seems to suggest the Lions expect him back sooner rather than later.
The fact that they were both dressed and out there were big steps in the right direction for both players, even if they were very limited.
As for starting center Frank Ragnow, he appears on track to play in Week 1. He participated fully in positional drills and was even taking reps with the first-team offense early in practice (we only get to see the first 15 minutes).