John Hopkins has hinted that he could be forced onto the sidelines for some time after revealing his accident during free practice at Assen caused muscle and ligament damage.

Coming less than a year after he suffered leg and ankle injuries in a smash at the circuit whilst competing in the MotoGP Dutch TT, Hopkins crashed on only his fifth lap around the track when he high-sided his Stiggy Honda and landed feet first.

Originally diagnosed with a dislocated hip, an injury that he says would have had him back on the bike for the next round in Italy, a trip to the local hospital went on to reveal that Hopkins has also torn the ligaments and muscles around the femur.

Set to fly home to the United States for possible surgery on Monday, Hopkins concedes the muscle damage is more serious than having broken bones.

"It looks like I am continuing my bad luck here in Assen two years in a row," said Hopkins, who was starting only his second WSBK race this weekend. "I didn't even get five laps under my belt this time. I had a huge high-side and landed feet first, which dislocated my hip and cracked the top of my femur.

"For about three hours, until they placed me in the operating room and put my hip back into place, I was in the most excruciating pain I have ever been in my life.

"I was really motivated to race here this weekend and initially I felt really good from the moment I jumped on the bike, but this is just bad luck. Now I will just have to recuperate. I will fly home tomorrow night and will have surgery Monday morning if necessary.

"The biggest problem will be the muscles. All the ligaments and muscles around the femur are torn, which is a lot worse then actual broken bones. If there was no muscle damage, I would be back racing in two weeks, now we will have to wait for the proper evaluation."

Stiggy Racing have made no mention of whether they will substitute Hopkins for the remainder of the weekend.