SUTURE TECHNIQUES AND COMMON TYPES OF SUTURES

SUTURE SIZES

Size denotes the diameter of the material. Stated numerically, the more zeros (0's) in the number, the smaller the size of the strand. As the number of 0's decreases, the size of the strand increases. The 0's are designated as 5-0, for example, meaning 00000 which is smaller than a size 4-0. (NOTE: Physicians will often say what sounds like "oh vicryl sutures" for instance -- by this they mean 0 Vicryl (zero Vicryl) not the letter "O")

USP	Diameter	Tensile Strength (surgeon's knot)
4-0	0.2mm	7.5N
3-0	0.3mm	12.3N
2-0	0.35mm	19.6N
0	0.4mm	22.3N
1	0.5mm	37.3N

Types of Suture Material:

Vicryl

Braided synthetic absorbable suture
Polyglactin 910
Retains 70% of initial strength at 10 days and 30% at 20 days
Complete absorption in 60 - 90 days

Coated Vicryl

As Above
Coated with a mixture of calcium stearate and polyglactin 370
Maintains 100% strength for ~ 45 days and then decreases to 70% by ~ 50 days
Needle sizes commonly used;
1 36mm taper
2/0 26mm cutting edge
3/0 22mm cutting edge

PDS

Mono-filament synthetic absorbable suture
Polydioxalone
Retains 70% of initial strength for ~ 21 days and is reduced to 50% at ~ 35 days
Absorption usually complete within 180 days
Results in minimal tissue reaction
Needle sizes commonly used;
1 40 or 26mm needle

Catgut

Intestinal submucosa of sheep and intestinal serosa of cattle
Retains tensile strength for ~ 10 days

Chromic Catgut

(Chromatised) retains tensile strength for 20 - 40 days
Both forms of catgut result in a moderate tissue reaction

Proline

Non absorbable synthetic mono-filament suture
Polypropylene (extruded)
Low tissue reaction and easy tissue passage
Needle sizes commonly used;
2/0 & 3/0 26mm cutting edge
6/0 13mm (epitendon)
8/0 6.35mm (digital nerve)

Nylon

Non absorbable synthetic mono-filament suture
Needle sizes commonly used;
5/0 18.7mm cutting edge

Ethibond

Braided non absorbable synthetic suture
Polyester coated with polybutilate (also a polyester) for lubrication to aid tissue passage with good tissue qualities and tensile strength
Needle sizes commonly used;
1 24mm cutting edge

Silk

Natural silk is made up 70% of protein fibre and 30% extraneous material such as gum
Processing involves degumming
Protein make up and extraneous material results in increased tissue reactivity

Steel

316L - SS Stainless steel
Inert with virtually no tissue reaction
Difficult to handle and knot

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