To injure a body part which has already been injured(verb)
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Use "reinjure" in a sentence
"It was here, on a night a little more than two years ago, that Reyes returned from a seemingly minor leg injury, only to reinjure himself in a game against the Dodgers."
"KevinBossman Kevin Boss Our biggest fear is that @SteveSmithNY will come back, score a touchdown, then reinjure his pectoral muscle flexing in the end zone. #showguns"
"PCL rehabs, like PCL surgeries, are tricky: If you go overboard in physical therapy, you can reinjure the ligament and set yourself back."