Lions rookie cornerback Terrion Arnold was added Thursday with a groin injury.
The good news is that Arnold didn't miss practice because of the injury. He was listed as a restricted participant. We'll certainly know more on Friday, but that doesn't sound like a major concern.
More good news: No Lions players on the active roster missed practice on Thursday. Arnold was the only one who wasn't fully involved. This is a very good sign for the 12th week.
That group also includes tight end Sam LaPorta, who missed Sunday's win against the Jaguars with a shoulder injury. He completed a full practice on Thursday, meaning he's leaning toward playing against the Colts on Sunday.