HI Well come to HCM Thank for asking I really appreciate your concern, soft tissue inflammation if happens due to fracture of bone then it may give rise to soft tissue as well as tissue inflammation which causes the blister formation, inflammation actually increases the local temperature of the skin superficial as well as internal which is high enough to form the blister, if the inflammation being controlled well then such blister formation can be prevented, underlying cause (Here the fracture bone needs to be surgically managed as early as possible to prevent further tissue damage ) till keep the leg elevated hope this information helps.