Things seemed to be improving every week for Aaron Rodgers. Ever since he suffered a left MCL sprain and bone contusion, we have seen weekly progress – more mobility, increased practice time, less bulky bracing. Unfortunately, things took a turn in the first play of Sunday’s game when he scrambled and took a hit from Lions linebacker Christian Jones.
Here’s the initial injury from week 1:
This video shows a valgus injury (force from the lateral or “outside” part of the knee causing it to bend inward) to Rodgers’ left knee. Here’s what that injury looks like in my 3 year-old’s crayon and marker…
A single valgus force on the knee causes both sprain (stretch) to the medial collateral ligament (MCL) and bruising to the bones in the lateral part of the knee from the simultaneous compression force.
This injury is incredibly painful. Bone bruises and MCL sprains are both limiting. Here is what Aaron Rodgers looked like running in week 2.
In the following weeks, however, Rodgers looked better and better. He was more mobile and shed his big bulky blue brace for a slimmer version. Unfortunately, in the first play of Sunday’s matchup with the Lions, Rodgers re-injured the knee.
Rodger’s second injury is the same mechanism as the first – another valgus stress to the knee. With a second injury, the MCL is further sprained and the recovery clock re-sets. That being said, I’m more worried about his bone bruise.
In the knee drawing on the left, the MCL is sprained and the lateral bone is bruised (shown as a white spot on the left side of the lower grey bone). If the knee suffers another valgus injury, as is the case in the drawing on the right, the MCL can become further stretched/torn. While that injury is painful and could affect play for the next month or so, it’s nothing to worry about long-term. Even full MCL tears heal.
What happens to the bone bruise in the drawing on the right is the most concerning result of a second valgus injury. As the already weakened bruised bone absorbs a second significant impact, the concern is that it can crack and the joint surface collapse.
A dramatic example of an injury like that is JJ Watt’s tibial plateau fracture. He sustained one very forceful valgus injury to his knee and was taken immediately for surgery to stabilize the bone in hopes that the joint surface would remain as “smooth” as possible. In the drawing on the right, notice that the joint surface is affected – as the bone collapses a bit, the joint surface becomes uneven and the cartilage coating it cracks (see the red outine below).
Collapse of the joint surface and cracking of the articular cartilage can lead to a form of osteoarthritis that makes ever playing football again very difficult.
So why the he## is Aaron Rodgers still playing? The best-case scenario is that Rodgers’ second injury was minor and resulted only in a re-stretch of the MCL with no real aggravation of the bone bruise seen on repeat imaging studies. I hope that this is the case.
If (when) Rodgers plays this weekend, expect him to be in a heavier brace – one that can better prevent the knee from bending inward again. A bigger brace will mean less mobility for the quarterback. We also may expect to see Rodgers running stiffly, similar to the way that he looked a week after the initial injury.
The Packers’ medical staff is known for being conservative when it comes to return to play decisions. If Rodgers is cleared to play this weekend, that likely means that his bone bruising is improving despite the recent re-injury. Still something to keep an eye on.