Yes, bruising on the back of the calf from constant over pressure can happen if knees are not bent enough coupled with too much forward highback lean or perhaps the calf comes down the leg(a woman's does more so than a guy's) too far for the fit of that particular boot. A "ghetto" way of attempting to remedy that issue could be to take a thick wristband(like a basketball player would wear) and put it on around the area in which the boot stops up on the leg to provide cushioning.