This time, it was a knee injury that put Henderson on the sidelines of Wednesday's practice. By Thursday, he was back in a limited capacity, but Vikings defensive coordinator Leslie Frazier said Henderson is still working his way back on a number of injury fronts.
"There are still some things that he is working through. He has really come a long way from training camp," said Frazier, referencing the dislocated toes that ended Henderson's 2008 season. "You could see some movement in some areas where you just knew that was going to come and the next step was going to come, and so on. He's just about where we expected him to be and he just has to keep playing and keep seeing things. When you miss 12 games of a season, to assimilate that is a tough deal. But some of the little things we do he's gotten a lot better at, and he will continue to get better at."
At first it was the dislocated toes that sidelined him for the remainder of the 2008 season after the fourth game. Then it was a shoulder injury last month that limited him in some practices but never kept him out of game action. This week, it was a knee injury.
Head coach Brad Childress said Henderson's mental toughness won't let him miss too much practice time.
"Linebackers, whether he's listed on the injury report or isn't, those guys are in the middle of everything all the time," Childress said. "They've got bumps and bruises and some of them are averse to treatment, don't want to be on the (injury) list. Grab a bag of ice and head on their way. Some of them have been brought up (old) school to stay out of the training room."
Before his season-ending injury in Week 4 last year, Henderson was playing at a Pro Bowl level. His explosion, aggressiveness and instincts propelled him through blocks and to the ball carrier.
This year, he wouldn't say his aggressiveness has been limited by the earlier shoulder injury, but he can see something that has been missing when he looks at the film.
"I wouldn't say (it's take away) aggressiveness. It's, you know, not to make any excuses. I don't know what it is. I looked at tape last year, seen a couple of plays that I might have missed this year," he said. "All I can do is try to keep improving every week – make the plays when I can, tackle when I've got the chance to and hopefully it will pick up and get back to that zone where I was at."
Frazier isn't surprised that Henderson downplays the shoulder injury and how it may have affected his performance over the last few weeks.
"He wouldn't say it has anything to do with it, but as an athlete it definitely affects you, but you try to play through whatever the ailments are," said Frazier, a former NFL cornerback. "They do sit in the back of your mind, especially after what he went through a year ago. To now have to deal with some other issues that affect him, I'm sure that it has some degree of affect on him mentally and making decisions and approaching the game the way he needs to approach it. He still plays extremely hard. He still makes a lot of plays for us, but some of those injuries, whether it be a shoulder or his knee, they do have an effect."
While there is an admission that he might not be playing at the level he was before his 2008 season was ended prematurely, all this isn't to say Henderson isn't still a leader. On the field, he is still making plays. He easily leads the team in tackles with 66, has one sack and is among the leaders in passes defensed.
Off the field, his speech to the team on the opening day of training camp made an impression on coaches and teammates. Missing 12 games in 2008 made him realize how much he loves the game. Despite his battles with shoulder and knee injuries this season, he still has the passion for the game and the confidence in his game.
"I'm definitely the same player. I don't think a player changes over the course of months or years. I'm still the same player," he said. "I'm just going to come in every week and do that same thing I've been doing – work hard, work hard at practice, try to lead this defense, no mental errors, and tackle. Hopefully we get there.
"We're 6-1 right now, so it's kind of hard to look at personal goals and what you've been doing personally. Defensively, I know we're probably not ranked where we want to be ranked, but it all comes back to wins and losses. Right now, 6-1 is the big thing. Hopefully we can continue on that road. Defensively, hopefully we can pick it up. Individually, I hope I can pick it up. I'm just going to keep working."
Tim Yotter is the publisher of Viking Update. Follow Viking Update on Twitter and discuss this story on our subscriber message board.