Injuries is mostly luck, but you can control certain things.

Playing against very weak abandon teams.

You are up against strong Hard Tackle defenders with a low morale and condition player.... the list goes on, each affecting the other.

Getting rid of injury prone player.

Players out of position.

Retraining injury prone players.

Over training.

Easy tackle.

All the above point and many more are factors, some points are hotly debated as to what if any they effect or reduces injury.

Nothing is set in stone with T11 when it comes to injuries.

P.S. Have you meet Morinhoseux?