A microscopic and biomechanical study of skin and soft tissue after repeated expansion.
BACKGROUND
Conventional expansion inadequately restores damaged skin for patients with large areas of skin deficiency or who lack sources of normal skin. These patients require repeated skin expansions, but little is known about the outcomes of this procedure.


OBJECTIVE
To evaluate the microscopic changes and biomechanical properties of skin and soft tissue after repeated expansion.


METHODS
We prepared three groups of six pigs each: a conventional expansion group, a repeated expansion group, and a blank nonsurgical control group. We measured histology, ultrastructure, basic fibroblast growth factor (bFGF), stress-strain, stress relaxation, and stress strength.


RESULTS
Skin obtained after conventional expansion and repeated expansion was basically healthy, but the microscopic and biomechanical properties differed from those of nonexpanded skin, especially in the repeated expansion group.


CONCLUSIONS
Repeated skin expansion involves growth under stress, simultaneous injuries, and further repairs, with fibers showing more injury signs than cells. This article describes the microscopic changes and biomechanical properties that occur after repeated expansion.
Huo
Ran
R
Department of Aesthetic, Plastic and Burn Surgery, Shandong Provincial Hospital, Jinan City, Shangdong Province, China. huoran@medmail.com.cn
Yang
Wang
W
Shangbin
Li
L
Tingting
Leng
L
Yang
Zhao
Z
Feng
Gao
G
Qingping
Yu
Y
Wenhao
Zhang
Z
D000818:Animals; D001696:Biomechanical Phenomena; D005346:Fibroblast Growth Factors / Q000032:analysis; D008854:Microscopy, Electron; D019651:Plastic Surgery Procedures / Q000379:methods; D012867:Skin / Q000737:chemistry* / Q000166:cytology* / Q000648:ultrastructure; D013314:Stress, Mechanical; D013552:Swine; D015626:Tissue Expansion
D005346:Fibroblast Growth Factors