Quick review of basic suture materials, needles and techniques for medical students and surgery residents

1. -D R A M R U T A U N A W A N E
( G E N E R A L S U R G E R Y )
Suture materials

2. Definition
 Suture material – Artificial fibers used to hold
traumatized tissue together till natural scarring and
healing takes place

3. Goals of Suturing
 Apposition of wound edges
 To provide adequate tensile strength
 Maintain hemostasis
 Aid in wound healing
 Prevent wound infection
 Reduce scarring and achieve asthetically appropriate
wounds

4. Ideal suture material
 Universally applicable to all types of tissue
 Easy to handle- No kinks, coiling, twisting
 Inert – Does not generate tissue reaction
 Strong – High tensile strength
 Frictionless – causing less tissue trauma
 Secure for tying reliable knots (non –slip)
 Able to be sterilized without composition changes
 Resists bacterial growth
 In certain areas, absorbability should be possible
 NON ALLERGIC, NON CARCINIGENIC NON
ELECTROLYTIC
 COST EFFECTIVE

5. Characteristics of suture material
 Tensile Strength
Force required to break when pulling two ends apart
 Depends on type of suture
 Thickness of suture
 Purpose for which being used
Knot strength
Force required for a knot to slip – considered when ligating arteries
Memory
Tendency to return to original shape (untied)
Tendency to stay in one position

6.  Plasticity – Ability to expand when stretched and not
return to its original length (Loosens with edema)
 Elasticity – Ability to return to its original length after
stretching, helpful in odematous tissue.
 Fluid absorption & capillary action: The tendency for the
suture to absorb water and facilitate infection
 Breaking Strength Rate (BSR): Approximate days after
placement when 50 % of breaking strength remains.

7. Suture Needle
 Made of either stainless steel or carbon steel
 Parts
 Tip/point
 Body/shaft
 Eye/swaged end

8. Needle Properties
 Sharp enough to penetrate tissue with minima
resistance
 Rigid enough to resist bending or breaking
 Sterile and corrosion resistant to prevent infections
 Stays stable in the grasp of needle holder
 Ductility – Needle’s resistance to breaking under a
given amount of bending

10. Technical specifications
 Needle Length
6mm, 8mm, 12mm, 18mm, 22mm, 30mm, 35mm,
40mm, 50mm
• Cross Section- round, cutting, reverse cutting,
tapercut, micro-point spatula curved
 Needle Curvature
 Straight, ½ circle, ½ circle double, 1/4th circle, 1/4th circle
double, 3/8th circle, 3/8th circle double, 5/8th circle, loop round

11. Curvature of surgical needles
 Curved needles allow predictable turnout from tissue
and require less space for maneuvering

12. Needle curve specifications

13. Cross section of needles

17. Eye (Swage)
 3 categories
 Closed eye – typical household sewing needle type
 French (Split or spring eye) Having slit from inside the eye to
the end of the needle with ridges that catch and hold the suture
in place
 Swaged (Eyeless) - Permanently attached to suture strand by
the manufacturer

18. Principle for selecting needle type

19. Classification of Suture Materials
 According to
absorbability
 Absorbable
 Non absorbable
According to
material
 Natural
 Synthetic
According to
structure
Monofilament
Polyfilament/
braided

20. Monofilament Polyfilament
 Single strand of
material
 Less traumatic
 Slips easily- more
knots needed
 Resists bacterial
harbouring
 Has more memory
 Contains several
strands
 Greater tensile
strength
 More flexibility and
pliability
 Knot security
 May harbour bacteria
Mono Vs Polyfilament

21. Monofilament Polyfilament

22. Question to ask when you see suture material --
 Is it natural or synthetic?
 Is it absorbable or non absorbable ?
 Is it mono filament or polyfilament ?

23. Absorbable Sutures
Natural
Monofilament
Plain
Gut
Synthetic
Monofilament
PDS
(Polydiaxone
suture)
Chromic
Gut
Braided
Monocryl
Vicryl
(polygalactin
suture)
Natural and absorbable sutures elicit more inflammatory reaction than non
absorbable and synthetic sutures

24.  Absorbable sutures are broken down by
 Proteolysis (Eg Catgut)
 Hydrolysis ( Ex Vicryl, Dexon)

25. Catgut
 Absorbable, Natural, Monofilament
 Made from submucosa of sheep intestinal tissue
(collagen)
 Plain catgut is destroyed in about a week
 Chromic acid delays hydrolysis and keeps it in tissue
longer (2-3weeks)
 High tissue reactivity
 Uses – Tubal ligation, episiotomy suturing, oral mucosa
suturing

26. VICRYL (polygalactin, braided)
Absorbable, synthetic, braided
Low elasticity
Tensile strength – 65% @ 14 days
- 40% @ 21 days
- 10 % @ 35 days
Absorption complete by 70 days

27. Polydiaxone (PDS)
 Absorbable, synthetic, monofilament
 Tensile strength – 70% @14 days
- 50 % @ 21 days
-14 % @ 56 days
 Completely absorbed @ 180 days
 Other types of absorbable synthetic sutures
 Polyglycolic acid (Dexon), Polygloconate (Maxon), Glycomer
(Biosyn)

28. Non Absorbable sutures
Natural Synthetic
Monofilament Braided Monofilament Braided
Stainless
steel
Silk,
Linen
Nylon Prolone
(Polypropylene)
Polyester

29. Silk
 Natural, non absorbable, polyfilament
 Has significant tissue reaction and inflammation.
 Handling and knot tying is very secure
 Lowest tensile strength
 Weaker when wet

30. Nylon
 Non absorbable, synthetic, monofilament
 Inert, no tissue reaction
 Significant memory – prone to knotting
 Surgilon, Ethilon, Dermalon

31. Polypropylene
 Non absorbable, synthetic, nonofilament
 Inert
 High Plasticity – Expands to prevent strangulation
but loosens when edema subsides
 Slips easily – requires extra knots
 Used for wound closure
 Prolone, Surgilene, Surgipro

37. Color coding