Houston Texans running back Arian Foster (23) breaks away from Indianapolis Colts safety Melvin Bullitt (33) on the way to his second touchdown of the day, during the fourth quarter of an NFL football game Sunday, Sept. 12, 2010, in Houston. (AP Photo/Dave Einsel)

For the second time in less than a week Houston Texan running back Arian Foster has cause a stir on twitter.

Foster tweeted a picture of an MRI of his hamstring, prompting questions about the severity of his injury and his openness about it.

"This is an MRI of my hamstring, The white stuff surrounding the muscle is known in the medical world as anti-awesomeness," he wrote while posting a link to the picture.

Foster defended providing the image to his Twitter followers with a tweet later Wednesday.

"If I had a 'significant injury' why post it? I'll be fine, it was jus meant to make fun of the whole situation. Humor is lost nowadays," he wrote.

Questions surround Foster's status for the season opener.