MMA Fighter Gruesomely Breaks Arm Mid-Round, But Continues Bout

Insane scene in a Halloween MMA match ... a fighter snapped her forearm in half -- BUT TRIED TO CONTINUE THE MATCH ANYWAY!!!

It all went down Saturday in Sao Paulo, Brazil at SFT MMA's Standout Fighting Tournament 22 ... when Sidy Rocha was taking on Karine Silva.

At some point during the first round ... the two fighters got on the ground -- and Silva appeared to lock Rocha's arm in a submission hold.

That's when Rocha's arm broke ... and, WARNING: THE VIDEO OF THE SCENE IS GRAPHIC!

But, to everyone's bewilderment ... Rocha tried to continue brawling -- despite the fact that her arm was hanging by nothing but skin!!

Eventually, the ref stepped in to stop the fight ... and you can see in the video, Rocha was NOT happy at all with the decision.

Docs ultimately were able to tend to Rocha's arm inside the cage ... and she'll now reportedly undergo an operation to fix the break.