LATEST: William Shatner has disclosed that his recent hospital stint was due to a painful kidney stone.

The 74-year-old actor was taken from the set of his hit TV show Boston Legal last week (ends21OCT05), suffering from what was initially reported to be chronic back pain.

But Shatner now reveals he had a kidney stone, which he successfully passed after experiencing excruciating pain.

He says, "I was doing a scene and I was feeling uncomfortable and then I got on my knees behind the scenes, before going on. And then I did the scene and I broke out into a cold sweat. I finished the scene and the nurse said, 'Maybe you should go to the hospital.'

"The purity of the pain! They had to give me morphine. It was just unbelievable pain and it made you kind of think about what pain is. It was awful."