A portable tensiometer for assessing surgeon's knot tying technique.

The purpose of this study was to determine the influence of surgeon's tying technique on knot security using O and 2-O monofilament and multifilament nylon sutures. By use of an Instron Tensile Tester and a portable tensiometer, knot security was achieved with these sutures using four-throw square knots (1 = 1 = 1 = 1). After didactic and psychomotor skill training, medical students were taught to construct the four-throw square knot using either a two-hand tie or an instrument tie. By use of the portable tensiometer, their knot tying techniques were judged to be superior to those used by a cohort of obstetricians and gynecologists. The surgeon's faulty technique can easily be corrected by didactic information and psychomotor skill training.