Over at SBNation, our resident medical expert Ali Mohamadi took a look at Matt Schaub's lisfranc injury. Long story short: it's very bad. Not only will it cost him the rest of the season, it may also threaten his entire career:
This clearly places Schaub's 2011 season in jeopardy, and the major concerns for the remainder of Schaub's career and beyond will be whether the injury heals sufficiently to prevent chronic pain and stiffness of the foot. This will depend upon the exact nature of the injury and how easy it will be to realign the damaged areas of the midfoot, a proposition that may require surgery.
The Lisfranc joint is the point at which the metatarsal bones (the long bones that lead up to the toes) and the tarsal bones (the bones in the arch, which include the cuneiform bones) connect. The Lisfranc ligament is a tough band of tissue that joins two of these bones. It is important for maintaining proper alignment and strength of this joint.
Located in the middle of the foot, the Lisfranc ligaments connect the heel and the ankle to the toes. When they've been damaged, it becomes impossible to generate power or put any pressure on the foot, both fairly essential parts of the job description of an NFL QB.
As Mohamadi explains, it's a fairly rare injury in the NFL, with the most famous case being former Philadelphia Eagles RB Duce Staley. After surgery, Staley was never able to regain the mobility in his foot and was never the same player.
It doesn't necessarily mean that Schaub will suffer the same fate, but recovering from this injury will be a time-consuming, arduous and yet delicate process.