It would depend on whether or not you have a pre-existing injury, either known or unknown. It would also depend on the severity of the injury. High reps could inflame an injured area causing the injury to react.
Re-injury occurred for me. However, it was only light probably due to lighter weight. In my case my right shoulder cannot follow the motion of bench press straight bar without hurting so I stick to dumbbells regardless of the weight.
Interestingly enough I have been recovering from shoulder surgery and was keeping reps in the 15-20 range. I started feeling more inflammation(from over use I was told). What was recommended to me was to warm up thoroughly using passive and active stretching and a few 10 pound lateral raises with thumbs pointed up.
Then I can do a few working sets of 10 reps and feel ok.. still not heavy, but I dont feel irritation.