[Viability and dynamic observation of stretchback of the continuously expanded skin flap in the pig model].
OBJECTIVE
To investigate the viability of the continuously expanded skin flap and the dynamic change of flap stretchback in the pig model.


METHODS
White piglets and a constant pressure-infusing pump were employed to establish a continuous tissue expansion model. The animals were divided into two groups. The short rectangular expander of 180 ml was used in group A and the long rectangular expander of 210 ml was used in group B. Three days after completion of the continuous expansion, normal random and expanded skin flaps were created to assess flap viability and stretchback.


RESULTS
Flap survival length in group A and B increased by 92.60% and 91.96% respectively versus normal random flap. But there was no significant difference in survival length between group A and B. Obvious flap stretchback was observed in the early stage. Eight weeks after flap operation the flap width of group A and B restored to that of the random skin flaps (P > 0.05).


CONCLUSIONS
Continuously fast-expanded skin flaps are reliable in viability for soft tissue reconstruction. Larger expanders cannot further enhance the viability of the expanded flap.
Li
J
J
Plastic Surgery Centre, Xijing Hospital, Xian 710032, PR China.
Lu
K
K
Xiao
J
J
D000818:Animals; D006085:Graft Survival; D016038:Skin Transplantation; D013524:Surgical Flaps; D013556:Swine, Miniature; D015626:Tissue Expansion