Mindwar (Book One of the Mindwar Trilogy) by Andrew Klavin

Rick Dial was a star quarterback for his Putnam Hills High School team until a car accident crushed his legs and made him dependent on crutches to even hobble 100 meters. Unsure of who he is without his athleticism, and embarrassed by his physical weakness, Rick retreats to the safety of his bedroom where he throws himself into video games and masters them. One day, while hobbling down the street, he is abducted by a government agency who convince him that the skills he displays during video play; coolness, quick thinking, and fearlessness are exactly the skills they need to combat a Russian cyberthreat to America known as the Realm. They want Rick to enter the Realm, and defeat the crazy genius who is masterminding the plot to control and disrupt American computer systems.
The biggest drawback is that, although Rick's body is fully functioning within the Realm, any injuries he sustains while in there are real, and when he withdraws from the Realm, the injuries remain. If he is killed while inside the Realm, he will remain in a coma forever in the real world. In spite of the very real threats to his existence, Rick realizes that this is a battle he has to face.
This is book one of a trilogy, guaranteed to be loved by those who enjoyed The Matrix or Ender's Game.

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