Surgical manipulation and the tensile strength of polypropylene sutures
P. B. Dobrin
Department of Surgery, Loyola University Medical Center, Maywood, Ill.
Laboratory studies were performed on 509 size 6-0 polypropylene sutures to
examine the effects of surgical manipulation on suture tensile strength.
Results showed that dragging sutures over the torn edge of the foil
package, permanently kinking sutures, or axially twisting them up to four
times did not decrease tensile strength. Similarly, the tug exerted by
operating room nurses on polypropylene sutures did not decrease their
tensile strength. Two manipulations, however, did decrease breaking
strength. The presence of a stray knot reduced suture strength 17%, and
grasping sutures with DeBakey forceps decreased suture strength in a
dose-dependent fashion. When experienced surgeons grasped sutures with
forceps out of direct vision, their grasping forces were well below that
which alters tensile strength. Nevertheless, these results demonstrate that
sutures that have acquired a stray knot should be discarded and that
sutures should not be grasped with mechanical devices such as forceps.
