Experimental Studies on the Repair of the Defect of the Cervicothoracic Trachea by Patching with the Sternocleidomastoid Muscle Pedicle Flap

In the adult mongrel dogs, the process of wound healing at the defect of the cervicothoracic trachea, which was patched with the sternocleidomastoid muscle pedicle flap, and its usefulness for the reconstruction of the trachea, were studied. The dogs were sacrificed 3.7, 14 and 30 days after operation. Macroscopically edema was seen 3 days after operation, but 14 days after operation it disappeared. Tracheal stenosis was not seen through all the healing stages. Microscopically firbroblast appeared and reepithelization was also observed 7 days after operation. Reepithelization was completed perfectly 30 days after operation. Hydroxyproline content decreased 3 days after operation, but increased to the normal range 14 days after operation. There was statistically significant difference in the increase of hydroxyproline contents between 3 days and 14 days after operation (p<0.01). The bursting pressure in the patched portion was measured by air inflation leak test. There was statisically significant difference in the increase of the bursting pressures between 3 days and 7 days after operation (p<0.01). The author concluded that the patching of the defect of the cervicothoracic trachea with the sternocleidomastoid muscle pedicle flap could be clinically used.