QB Matt Schaub has started every game for the Texans over the last two seasons. Unfortunately for Houston, he he was taken to the hospital overnight Tuesday and missed practice today with a bursa sac injury in his right knee.

His backup, QB Dan Orlovsky, has not thrown a pass since 2008.

Texans coach Gary Kubiak said the injury will not require surgery:

"Everything should be OK," Kubiak said. "I expect him here [on Thursday]. If that's the case, and he's doing what he normally does, he'll be out there [on Sunday]."

Texans wide receiver Andre Johnson had some thoughts as well:

"We're very concerned,'' Johnson said. "Guys didn't know what was going on. He's our starting quarterback. You don't want to go into a game without your starting quarterback.''

Received some questions regarding "What is a bursa sac injury?"

Well, it's basically inflammation, and usually takes place in the knee. And yes, it is very nasty, and very painful. It usually stems from over-use of a certain muscle, which is why it is common in athletes. WebMD broke it down:

Bursitis is the inflammation or irritation of the bursa. The bursa is a sac filled with lubricating fluid, located between tissues such as bone, muscle, tendons, and skin, that decreases rubbing, friction, and irritation.

The most common symptom of bursitis is pain. The pain may build up gradually or be sudden and severe, especially if calcium deposits are present