Scratching sound when brakking

Hi

Always when i am braking i can hear scratching intermitted noise from rear drivers side. Firstly i though that it could be rear brake shoes so bought new and when i took the rear drums off, brake shoes are like new. So put back everything together and no sound at all till now. Don't know why it is there or what it could be but it is only if i am braking. 

That sound has started when i replaced the rear springs. I have realised that rear strut bumps are ripped (they are in two pieces) but the are like that for i don't know how long and didn't have this sound before.

Anyone has any suggestions what this could be?