Fracture blisters are skin bullae representing areas of epidermal necrosis. The stratified squamous cell layer separater from underlying vascular dermis by edema fluid. They commonly occur in areas where there is tight adherence of the skin to the underlying bone with little or no subcutaneous tissue in between.
Areas where fracture blisters occur commonly are the ankle, wrist, elbow and foot. Fracture blisters significantly alter the treatment plan. They cause application of splints,casts and the site and timing of surgery difficult.
Mechanism of Fracture Blister formation
A force that causes fracture of the bone also cause sprain in the overlying skin resulting in cleavage the the skin usually at the dermo-epidermal junction. Blisters are formed by collection of fluid in this cleavage. Fracture blisters form by two principal forces:
i)Increased filtration pressure arising from interstitial force due to edema and swelling of the the fractured extremity. This leads to decreased cohesion between the epidermal cells and facilitate fluid transport in the blister.
ii)Increased colloid pressure in the cleft in the dermo-epidermal junction leading to drawing of fluid toward the blister.
Of these two mechanisms the former one remains more significant.
Apart from this, the deforming force also causes injury to the underlying vessels and lymphatics leading to tissue hypoxia and epidermal necrosis.
Fracture blister usually resemble a second degree burn.
Fracture Blisters are usually of two types :
- clear fluid filled blister (serous blister) and
- hemorrhagic blister.
Clear fluid-filled blisters have minimal injury to the dermis with some epidermal cells remaining attached, healing in approximately 12 days.
Hemorrhagic blisters represent a more severe injury where the dermis is completely stripped of epidermal cells, taking approximately 16 days to heal
Management of fracture blister still remains controversial, though a lot of researches are undergoing.
There are various school of thoughts. Some researchers believe that blisters should be left intact and surgical intervention should be done only once the blister subsides. Others advocate surgical intervention should be as early as possible to avoid blister formation and even if blister forms intervention should be done regardless of the blister.
To conclude, we believe fracture blisters are better left intact to maintain the sterile environment.
Early intervention is possible; before formation of blister ; is always better. But once the blisters form, it is better to leave them till healing.
Although to get a definite answer further researches should be done. We request you to share your reviews regarding your experience.