The efficacy of MEBO in treating wounds after resection of thrombotic external hemorrhoids and excision of old anal fissure;

Purpose: at the present time operative treatment is the most effective way to treat the old anal fissure.

By means of chemical analysis,mechanical Property test,macroscopic examination,microstructure examination and fracture morphology observing,this paper established that the old cracks had existed before installation and these cracks will expand by sudden overload during operating and therefore failure will occur.

Size shrinkage and old cracks affecting the grouting quality