This document provides an overview of suturing techniques and knot tying. It discusses the history of suturing dating back to ancient Egypt, different suture materials and needles, wound healing processes, and various suturing techniques like simple interrupted, vertical mattress, and subcuticular stitches. It emphasizes the importance of mastering suturing skills like tying secure square knots using proper two-handed techniques to aid in wound healing and produce good cosmetic results.

1. Sutures, Needles,
Suturing Techniques,
and Knot Tying
Dr. D. W. Daugherty
Department of Surgery
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2. Goals of Suturing
• Aid in wound healing
• Avoid wound infection
• Assist hemostasis
• Produce aesthetically pleasing scar by
approximating skin edges
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3. Historical Landmarks
• The earliest records of surgical suture date
back to 3500 B.C. in Egypt. The script is now
known as The Edwin Smith Surgical
Papyrus.
• The oldest physical evidence of surgical
suture dates to between 500-100 B.C.
Evidenced by several mummies who had
been sutured which were found in Egypt.
• Hippocrites first used the term ‘suture’ in
400 B.C. The meaning is literally to ‘sew’ or
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4. Historical Landmarks
• In 100 B.C., Cornelius Celsus, a Roman,
used the word as a noun and a verb – “the
suture” and “to suture”.
• The first sutures were fashioned from hair,
cotton, tendon, or silk. They were used on
needles made of bone, stone, or wood.
• Sutures were originally used to close open
wounds, but shortly were adapted to ligate
tissue as well. This method was successful
but infection rate was extremely high.
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5. Historical Landmarks
• In 1867, Joseph Lister first attempted to sterilize
suture. He used silk suture that was ‘sterilized’ in
carbolic acid. The first trials were unsuccessful.
• In 1869, Lister changed to ‘catgut’ suture, which
was being widely used in Germany due to its
absorbability. The trials showed great reduction in
infection rates.
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6. Historical Landmarks
• Inspired by the data from Joseph Lister, Robert
Wood Johnson and his brothers, Edward Mead
Johnson and James Wood Johnson, started a small
business in 1885 – they named it Johnson &
Johnson.
• In 1886, Johnson & Johnson was the first company
to mass produce Joseph Lister’s sterile catgut
suture.
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7. Historical Landmarks
• Johnson & Johnson, off of its success from
sterile suture and sterile dressing sales,
became incorporated in 1887.
• In 1906, Iodine was first produced in
Germany by the B. Braun Company.
• In 1956, Johnson & Johnson created an
independent division for its suture
production and sales – it was named
Ethicon.
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8. Wound healing
• Phases of wound healing
– Coagulation begins immediately following injury
– Epithelialization of the surgical repair should
occur within 48 hours of suturing
• New blood vessel growth peaks at 4 days
– Collagen reformation starts at 48 hours, peaks at
1 week and continues for 12 months
– Wound contraction starts 3-4 days and can last
up to 2 years after the injury / repair
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9. Factors limiting wound
healing
• Steroids
• Sepsis
• Malnutrition
• Diabetes
• Obesity
• Smoking
• Chemotherapy and Radiation
• Anticoagulants
• Antiplatelet medications
• Collagen and Vascular Diseases
• Local factors
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10. Layers of Skin
• Fascial closure is usually, but not always required.
• Approximation of the subcutaneous tissue aids in healing by closing
dead space.
• Approximation of dermis achieves good surface alignment and relieves
tension so the epidermis can be closed with a good cosmetic result.
• The best cosmetic results occur if the epidermis is perfectly aligned
and tension free. This is ensured by proper closure of the deeper
layers.
Epidermis
Dermis
Subcutaneous tissue
Deep fascia
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11. Suture Material
• Absorbable vs. Non-Absorbable
• Natural vs. Synthetic
• Monofilament vs. Braided
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12. Suture Material
• Absorbable
– Natural: Gut - beef serosa or sheep submucosa
– Synthetic: Vicryl, Monacryl, PDS
• Non-Absorbable
– Natural: Silk, Steel, Cotton
– Synthetic: Nylon, Prolene, Ethibond, Dacron
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13. Suture Material
• Monofilament
– Monacryl, Nylon, Prolene, PDS, Gut, Steel
• Braided
– Silk, Cotton, Vicryl*, Ethibond, Dacron
* Manufactured in monofilament and braided 13
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14. Suture Material
• Uncoated
– Plain suture. If absorbable, breaks down faster.
• Coated
– Chromic, Polyglactin, Antibiotic. If absorbale, delays
breakdown.
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15. Suture Size (Diameter)
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16. Suture Size (Diameter)
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17. Suture Properties
• Absorption:
– Progressive breakdown and loss of mass and/or
volume of suture material; does not correlate with
initial tensile strength. Ultimately, tensile strength
is lost as the suture degrades.
• Capillary Absorption :
– Extent to which absorbed fluid is transferred along
the suture.
• Fluid Absorption:
– Ability to take up fluid after immersion.
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18. Suture Properties
• Tensile Strength:
– Measure of a material or tissue's ability to resist
deformation and breakage
• Breaking Strength:
– The tension at which suture failure occurs. The
maximum limit of the tensile strength.
• Elasticity:
– Measure of the ability of the material to regain its
original form and length after deformation. If
deformed beyond its elastic property, the suture is
greatly weakened.
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19. Suture Properties
• Plasticity:
– Measure of the ability to deform without breaking.
• Memory:
– Inherent tendency of suture material to retain its
shape. Related to the elasticity, plasticity, and
diameter of the suture.
• Pliability:
– Ease of manipulating the suture, such as the ability
to adjust knot tension and to secure knots. Related
to the suture material, filament type, and diameter.
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20. Suture Properties
• Straight-Pull Tensile Strength:
– Linear breaking strength of suture material.
• Knot Strength:
– Amount of force necessary to cause a knot to slip
(related to the coefficient of friction and plasticity)
• Knot-Pull Tensile Strength:
• Breaking strength of the knot.
(10-40% weaker at knot)
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21. Suture Properties
• Suture Pullout Value:
– The amount of force on a suture required to cause
tissue failure.
• Measurement of the strength of a particular tissue
• Variable depending on anatomic site and composition
(fat, 0.2 kg; muscle, 1.27 kg; skin, 1.82 kg; fascia, 3.77 kg)
• Wound Breaking Strength:
– Limit of tensile strength of a healing wound at
which separation of wound edges occurs. Based
on collagen properties.
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22. Suture Construction
• The point is the sharpest portion and is used to
penetrate the tissue. Shape varies. Delicate!
• The body represents the mid portion of the needle. Solid
Steel. Strongest portion.
• The swage is the portion to which the suture material is
attached. Instrumentation here will break or weaken the
suture. 22
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23. Needle Types
• Tapered:
– The needle penetrates and passes through tissues
by stretching without cutting.
– Used for easily penetrated tissues (SubQ, Dura,
Peritoneum, Abdominal Viscera).
– Minimizes potential tearing, bleeding, and tissue
damage. 23
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24. Needle Types
• Cutting:
– Conventional versus Reverse Cutting
– The needle has 2 opposing cutting edges
– Designed for penetration through dense tissue
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25. Needle Types
• Intestinal
– Either a Taper-Cutting or a Taper-Point needle.
Designed to make a hole slightly smaller than the
diameter of the suture. The hole is then ‘sealed’ by
the suture.
– Especially good for the GI tract, biliary tract, dura,
urogenital tract, and blood vessels.
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26. Needle Types
• Blunt
– Blunt-Point design for suturing tissue that is
extremely friable or densely vascular.
– Liver, spleen, kidney, pancreas.
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27. Needle Shapes
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28. Needle Sizes
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29. Suture Technique
• A needle holder is used to
grasp the needle at the
distal portion of the body,
one half to three quarters of
the distance from the tip of
the needle.
• The needle holder should
not be tightened excessively
because damage to both the
needle and the needle
holder may result.
• Incorrect placement of the
needle in the needle holder
may result in a bent needle,
injury to the tissue, and/or
an undesirable angle of
entry into the tissue.
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30. Suturing Technique
• A needle holder is held with
the first and fourth fingers in
the appropriate finger holes.
The second and third
fingers are used for
stabilization and fine control
of the instrument.
• Surgeons who have
mastered the foundational
techniques can then modify
their technique as needed
(eg. ‘palming’ the driver).
• When suturing, always sow
towards yourself.
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31. • The tissue must be stabilized to
allow needle placement. Toothed
or plain forceps may be used to
gently grasp the tissue. Excessive
trauma to the tissue being should
be avoided to reduce the possibility
of tissue strangulation and
necrosis.
• Forceps are meant primarily for
grasping tissue. Not for handling
the needle.
• Sometimes it is necessary to grasp
the needle as it exits the tissue
after a pass. Grasping and
stabilizing the needle should be
done prior to releasing the needle
holder. Otherwise, the needle may
become lost in the tissues.
Suturing Technique
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32. • The needle should always
penetrate the tissue at a 90°
angle; that is, in a perpendicular
plane. This minimizes the size of
the entry wound and promotes a
proper path through the tissue.
Not doing so results in excessive
tissue damage and sub-optimal or
incorrect positioning of the
suture.
• The distance traveled, depth, and
angle of the suture depends on
the surgeon goal. In general, the
2 sides of the stitch being placed
should be mirror images, with the
needle also exiting the tissue in a
perpendicular plane.
Suture Technique
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33. • Simple, uncomplicated wounds
• Easy technique to learn
• If one breaks, integrity of
closure is maintained
• Slow to apply
• Skill required to get ideal
spacing and tension
Simple Interrupted
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34. • Simple, uncomplicated
wounds
• Physics similar to simple
interrupted
• Even tension along suture
• Fast application
• Less knots, but break one
and the whole stitch unravels
Simple Running
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35. • Can be either running or
interrupted
• Simple, uncomplicated wounds
• Excellent cosmetic closure
• No stitches to remove
• Technically more difficult to
master
• Doesn’t hold in thin skin
Subcuticular
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36. • Achieves good wound edge
eversion
• Some claim cosmetically superior
to vertical mattress
• Thick skin and subcutaneous tissue
– Feet, hands, back
• Good for wounds under tension
• Makes a “box” shape
Horizontal Mattress
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37. • Excellent for deep wounds and/or
wounds under high tension
• If done well, very good cosmetic
result
• Good eversion of wound edges
• Thick skin and subcutaneous
tissue
• Approximates deep tissue and
superficial tissue with one stitch
Vertical Mattress
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38. Other Common Stitches
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39. Knot Tying
• Make sure you tie a square knot
• Reverse your hands
• If you don’t…
– Granny knots and slip knots will not hold
– Require more throws – add to bulk
– Increased likelihood of dehiscence or infection 39
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40. Knot Tying
• Square (Reef) Knot: essential for knot strength
• Surgeon’s Knot: double throw on the first half-hitch
• Slip Knot: good for tension and can be converted to a square
not by crossing hands
• Number of throws
• Too many
– Bulky knot is a nidus for infection
• Too few
– May not hold
• Tails
• According to a any good surgeon, there are only two suture tail
lengths: 1) too short and 2) too long…
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41. • The needle holder is placed parallel with the incision (or vessel) being tied.
The long end of the suture is wrapped around the tip of the needle holder
in a clockwise direction forming a loop. The short end of the suture is
grasped with the needle holder and pulled through the loop. Bring the
short end of the suture toward you. This creates the first hitch of a square
knot.
• The second hitch is formed by wrapping the long end of the suture around
the instrument in a counterclockwise direction. The short end of the suture
is then grasped and pulled through the loop. Pull the needle holder away
from you, squaring the knot.
Instrument Tie
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42. • The greatest precision in maintaining constant tension
on the suture during the tying process
• Preferred by most surgeons (especially when others
are tying)
• Easier of the techniques to master successfully
• More reliably produces square knots
• If you want to be a surgeon, master this technique
Two Handed Tie
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43. • The one-handed knot is so named because all of the
maneuvering, including releasing and re-grasping the
free end, is done with one hand. The other hand
merely holds the fixed segment taut.
• One handed knots have the advantage of allowing
more speed in tying, but have less tension control of
the segments.
• The maneuvering is done with the left hand so that a
surgeon tying his own knots during suturing can
continue to hold the needle holder in his right hand.
• More difficult to achieve excellent square knots.
Unforgiving of lapses in technique.
One Handed Tie
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44. Suture Removal
• Abdomen 10-12 days
• Back 10-12 days
• Chest 10-12 days
• Extremity 10-14 days
• Hands & Feet 10-14 days
• Knee & Elbow 12-14 days
• Scalp 10-12 days
• Eyebrow 4-5 days
• Eyelid 4-5 days
• Face 4-5 days
• Lip 4-5 days
• Neck 5-6 days
• Oral Cavity 6-8 days
• Pinna (ear) 4-6 days
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46. Summary
• Essential to aid in wound healing and achieve acceptable
cosmesis when closing wounds.
• Mastery is essential to all aspects of surgery, from maintaining
hemostasis to restoring proper function of the organ systems.
• Knowledge of the suture materials, needles (type, size, and
shape), instruments, and techniques are absolutely necessary
in order to be a competent surgeon.
• Everyone thinks they can tie, but there is a big difference
between simply being able to do something and doing it
correctly. Tie secure, square knots.
• Master Two Handed Ties first.
• Practice, Practice, Practice! 46
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47. Questions?
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