Abstract:

Objective: To study the relationship of diaphragmatic injury and pectus excavatum in rats. Methods: Forty SD rats were
divided into 2 groups, intervene group received the operation of injury diaphragm, and the control group received the sham operation.
At the age of 12 weeks, all rats were sacrificed for observations of the chest appearance and histology and morphology of diaphragm.
Results: The incidence rate of the pectus excavatum in intervened SD rats was 38.89% （7/18）after diaphragm contracture.
Compared to the control group, the incidence rates were different with statistic significance. The muscle fiber structure was loose and
disordered; the muscular atrophy, hyperplasia of fibrous connective tissue and scar formation were found in diaphragm injure.
Conclusion: Injuried diaphragm led to contracture after diaphragm cicatricle healing, the contracture of diaphragm created a
continuous stretch power on anterior chest wall, the force may be one of the factors which induce pectus excavatum.

Key words: diaphragm injury, pectus excavatum, experimental research, SD rats