On the origin and evolution of the Roeder knot and loop--a geometrical review.

The first laparoscopic sliding knot to be described was the Roeder knot; it has been used for a variety of procedures in all surgical disciplines. It was surmised that the introduction of new modifications in the geometry of the knot paralleled the introduction of its new indications, and that not all modifications improved its security. Therefore, a geometrical review was made of all modifications and all data on knot security and loop security of the knot were analyzed. The introduction of the original knot and its 14 applicable modifications paralleled the increase in minimally invasive techniques and the spread of these techniques in all the medical specialties. Roeder loop security depends predominantly on the number of initial turns around the standing part. Its knot security depends on the additional half hitches used to backup the knot after it has been tightened. Only a few of the modifications improved the security of the knot or its previous modifications.