Keanu Reeves recently shared details about a gruesome injury he sustained on the set of a new comedy directed by and starring Aziz Ansari.

The film, which also features Seth Rogen, has its plot tightly under wraps and no release date has been announced yet.

Reeves, 59, was photographed earlier this year walking with crutches and an ice pack wrapped around his left knee.

Ansari later revealed that Reeves had fractured his kneecap.

Reeves recalled the incident, saying, 'I was filming a scene with Aziz Ansari and Seth Rogen, and we were in a cold plunge.

I was loving it, standing there, and we finished the scene.

You know when you’re cold and you’re shuffling? I had a bathing suit and a towel, and you put it over your head and do the cold shuffle.

I was doing the cold shuffle in this room that had protective carpets down, and then, just here, there was a little pocket, and my foot got caught in the pocket in the shuffle, and then I went down, but my knee didn’t follow.

And then, in slow motion, I went falling.

My arms came out, but then my knee failed because it’s got some stuff, and I spiked it.

And my patella – kneecap – cracked like a potato chip,' he added, causing the host and audience to groan.

While Reeves initially thought he was fine, he knew something was wrong when 'my knee was blowing up.

' He quipped, 'Comedy’s hard, man.

' When asked by Colbert whether cracking his kneecap was the worst thing that’s ever happened to him, Reeves responded, 'No, the two-level fusion of my spine was.

' Recalling the procedure, which was completed just before he began training for a film, Reeves remembered, 'I was losing feeling, and I was kind of starting to fall in the shower, and I went to see this doctor, and he was like, ‘We need to do surgery right now.

’' He said that his spinal cord was squeezed between portions of his spinal discs that were splintered and compressed.

He had to wear a contraption around his neck to ensure his spine could fuse properly, which required production to reschedule his fight scenes.