- the knot is the weakest part of a suture line
- knot security depends on
- the technique used to tie the knot
- the physical characteristics of the suture material
- a throw is the motion of wrapping the strands of the suture around each other and pulling on the ends to tighten them
- a simple knot consists of 2 throws (it tends to untie when under tension)
- a secure knot requires at least 4 throws (specific number varies with how slippery the suture material is)
- for continuous patterns, 5-6 throws are placed on the beginning knot while 5-7 are placed on the ending knot
- Additional throws are needed because of :
- extra tension on the knot
- addition of an extra strand because a loop is tied instead of a single strand
- ends of the suture should be left long enough that they do not untie (at least 3 mm, but varies with the suture size and material)
- first, become consistent at using the proper technique to tie a good knot, then work on speed
