Fracture blisters.

A clinical and histological study was performed on fracture blisters found in association with 13 surgically treated ankle fractures. The timing of surgery was dependent upon soft tissue swelling; the status of the blister did not affect this aspect of the decision making process. The average time from injury to surgery was 2.1 days (range, 1-3 days). At the time of surgery all blisters were intact. Skin biopsies were obtained from the edge of the incision in proximity to the blister, and from the bed of the blister when the incision was made through the blister. Clinically, 2 blister types were identified: (1) clear fluid filled, and (2) blood filled. Histologically, both blister types demonstrated a cleavage injury at the dermoepidermal junction. However, the dermis of the clear fluid filled blister retained occasional epithelial cells, while the dermis of blood filled blisters was completely devoid of epidermis. Minimal to no evidence of dermal injury was found in histologic sections from the blister beds or from the skin in close proximity to blisters. All incisions made through and around skin blisters went on to heal without evidence of infection or wound breakdown. Delayed wound healing occurred in 1 patient in whom an incision was placed through a blood filled blister. The blood filled blister appears to represent a slightly deeper injury than the clear fluid blister and had a higher risk of poor healing of surgical incisions.