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Types of Sutures

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Part 1: Classification by Material

Master Classification Diagram

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A. Absorbable Sutures

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B. Non-Absorbable Sutures

Source: Roberts and Hedges' Clinical Procedures in Emergency Medicine, Table 35.1; Fitzpatrick's Dermatology, Table 202-5

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Monofilament vs. Multifilament

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Suture Size (USP Scale)

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Part 2: Classification by Stitch Technique

Basic Suture Patterns

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1. Simple Interrupted Suture

• Advantage: If one suture fails, the rest hold. Allows precise tension adjustment at each bite.
• Use: Small punch biopsies, layered closures, high-tension wounds, areas needing exact edge apposition
• Key point: A single suture can be removed to inspect the wound without compromising the full closure

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2. Buried (Deep Dermal) Suture

• Advantage: Reduces tension on the surface, promotes wound eversion, minimizes dead space, avoids suture spitting
• Variants: Conventional buried suture (mild eversion) and buried vertical mattress (greater eversion)

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3. Simple Running (Continuous) Suture

• Advantage: Much faster than interrupted; evenly distributes tension
• Disadvantage: If suture breaks anywhere, the entire closure is compromised
• Use: Long wounds under minimal tension with well-approximated edges

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4. Running Locked (Ford Interlocking) Suture

• Advantage: Creates pressure along the wound edge - useful in highly vascularized areas for additional hemostasis
• Use: Scalp wounds, areas with active oozing

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5. Running Subcuticular (Intradermal) Suture

• Advantage: No external suture marks ("railroad tracks"); can be left in place 2-3 weeks; ideal if patient cannot return for removal
• Use: Trunk and extremity closures; cosmetically sensitive wounds

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6. Horizontal Mattress Suture

• Advantage: Excellent tension reduction; useful as a retention suture for large wounds; good wound eversion
• Caution: Can strangulate poorly vascularized tissue (e.g., flaps) - use with care

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7. Vertical Mattress Suture

• Advantage: Closes both deep and superficial layers simultaneously; promotes strong wound eversion
• Use: Areas prone to inversion (e.g., back of neck, dorsum of hand); high-tension closures

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8. Purse-String Suture

• Use: Partial or complete closure of circular defects (e.g., after punch excisions); reduces healing time for second-intention wounds

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Quick Reference Summary

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Individual Sutures - Detailed Guide with Images

The following covers every major suture technique used in surgery, emergency medicine, and dermatology, drawn from Roberts and Hedges' Clinical Procedures in Emergency Medicine, Hinman's Atlas of Urologic Surgery, and Andrews' Diseases of the Skin.

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Visual Overview of All Major Suture Patterns

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GROUP 1: INTERRUPTED SUTURES

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1. Simple Interrupted Suture

• The needle enters the skin perpendicularly, ~4-8 mm from the wound edge on one side
• It passes through the full thickness of skin and exits the opposite side at the same distance
• The suture is tied and cut; the process repeats along the wound

• Each suture is completely independent - if one fails, all others remain intact
• Allows precise, individual tension control at each bite
• Slightly time-consuming compared to continuous techniques

• The most commonly used suture in clinical practice
• Small punch biopsy closures
• High-tension wounds where individual adjustment is needed
• Layered closures combined with deep dermal sutures
• Wounds where early partial removal may be needed (e.g., infected wound monitoring)
• Facial lacerations requiring precise edge alignment
• Any wound where a step-off deformity (epidermal level mismatch) needs correction

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2. Buried (Deep Dermal) Suture

• The needle starts deep in the dermis/subcutaneous fat, enters from below, and the knot is buried away from the skin surface
• The stitch is in the dermis and fat; the knot is cut short and buried to minimize tissue reaction
• Two variants: Conventional buried (mild eversion) and buried vertical mattress (moderate to significant eversion)

• Knot sits entirely below the skin - no external visible suture
• Gradually loses tensile strength as the scar gains its own intrinsic strength
• A scar has only 5-10% of original skin strength at 2 weeks - this suture bridges that gap
• Reduces tension on the surface closure, minimizes dead space, and promotes wound eversion

• Deep layer (dermal/subcutaneous) closure in any layered wound
• Prevents wound dehiscence in larger or deeper wounds
• Eliminates dead space to reduce hematoma/seroma risk
• Situations where the patient cannot return for suture removal (absorbable suture used)

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3. Vertical Mattress Suture (Near-Far, Far-Near)

• First, a deep wide bite is taken 6-8 mm from the wound edge, passing through full thickness (the "far-far" bite)
• Then a superficial narrow bite is taken 1-2 mm from the wound edge, passing through only the upper dermis (the "near-near" bite)
• Both bites are on the same axis (perpendicular to the wound), creating a figure-8 shape

• Closes both deep and superficial layers simultaneously with a single suture
• Strong wound eversion - the most reliable technique for everting wound edges
• Eliminates dead space
• Requires more time and may cause more tissue strangulation than simple interrupted

• Areas prone to wound inversion (dorsum of hand, back of neck, scalp)
• High-tension closures needing both deep and superficial support
• Alternatively placed between simple interrupted sutures for eversion in difficult areas
• Can replace a two-layer closure (deep + surface) in areas without excessive tension

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4. Horizontal Mattress Suture

• The needle enters the skin and crosses the wound like a simple interrupted suture
• Instead of tying, the needle re-enters 6-8 mm laterally on the same side it exited
• It then crosses back to the starting side, exiting directly across from the second entry
• Both ends end up on the same side and are tied, creating a rectangular suture loop

• Orients 90 degrees to the vertical mattress pattern
• Distributes tension over a wider area than simple interrupted
• Risk of tissue strangulation and necrosis in poorly vascularized tissue (e.g., flaps)

• Reducing tension in large wounds or wounds under high static tension
• "Retention suture" for very large wounds
• Areas where eversion is desired but subcutaneous tissue is sparse
• The half-buried horizontal mattress variant (corner stitch) is ideal for the apex of V-shaped flaps - protects the tip without compromising its blood supply

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5. Figure-of-Eight (Cruciate Mattress) Suture

• Like a horizontal mattress but the second pass crosses diagonally, creating an X (cross) shape on the skin surface
• Results in two overlapping triangular loops that share a common knot

• Distributes tension in two directions simultaneously
• Strong tension-distributing properties in a compact stitch
• Also called the "cruciate suture" or "cross mattress suture"

• Fascial closure (e.g., abdominal wall fascia)
• Tendon repair
• Areas requiring strong tension distribution in a small space
• Bone/periosteum suturing in orthopedic and dental procedures
• Closing the apex of a complex V-shaped wound

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6. Far-and-Near (Smead-Jones) Suture

• A large bite (far-far) through all layers of the abdominal wall is taken, then a smaller bite (near-near) through the fascial edge only
• Creates a combined deep and superficial bite in one stitch

• Provides mass closure of multiple layers simultaneously
• Strong and distributes tension across the entire wound width

• Abdominal wall (mass closure) - laparotomy closure
• Closure of fascia in re-operations or contaminated wounds (Smead-Jones technique)
• Reduces risk of incisional hernia in high-tension midline closures

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GROUP 2: CONTINUOUS (RUNNING) SUTURES

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7. Simple Running (Over-and-Over) Suture

• Begins with a single interrupted stitch at one end, tied but not cut
• The needle then continues along the wound, taking successive equal bites at equal intervals, crossing the wound at a consistent angle
• A final knot is tied at the other end using the last loop and the free end

• Tension is distributed evenly along the entire wound length
• Faster than interrupted sutures - only 2 knots for any wound length
• Accommodates mild wound swelling
• Disadvantage: If suture breaks anywhere, the entire closure may fail

• Long, low-tension wounds with well-apposed edges
• Cosmetic surface closures when subcutaneous layer has been properly closed
• Scalp lacerations (fast and effective)
• Peritoneum and fascial closures

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8. Running Locked (Ford Interlocking) Suture

• A continuous suture where the needle passes through the loop of the previous stitch before entering tissue on each pass
• Creates a locked chain pattern where each bite self-locks

• Creates additional pressure along the wound edges
• More hemostatic than simple running due to compression of wound edges
• Cannot easily adjust individual loop tension after placement

• Highly vascularized regions where hemostasis is needed (scalp, oral mucosa)
• Situations requiring firm edge apposition with simultaneous compression
• Gastric or intestinal mucosal edges (avoiding puckering)

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9. Running Subcuticular (Intradermal) Suture

• The suture runs horizontally through the dermis just below the epidermis, alternating sides
• The needle enters the wound from one end (parallel to the incision), takes horizontal bites in the dermis alternating between sides, and exits at the far end
• No visible suture crosses the skin surface

• No "railroad track" or cross-hatch marks from suture penetration
• Can remain in place for 2-3 weeks without scarring
• If a single loop comes out in the middle of a long wound, it facilitates removal
• Absorbable suture eliminates the need for removal entirely

• Cosmetically sensitive wounds (face, neck, chest)
• Trunk and extremity closures where sutures must stay 2-3 weeks
• Patients who cannot easily return for suture removal
• Post-surgical incision closure in elective procedures

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10. Interrupted Subcuticular (Horizontal Dermal) Suture

• Individual horizontal bites within the dermis on alternating sides, each tied separately
• The knot is buried beneath the skin surface

• Provides dermal support without surface penetration
• More flexible than running subcuticular - each bite is independent
• Suitable for wounds with strong static skin tension

• Deep dermal closure for wounds requiring prolonged support
• Areas where running subcuticular would fail due to high tension
• Layered wound closure in areas prone to dehiscence

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GROUP 3: VISCERAL / BOWEL SUTURES

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11. Lembert Suture (Inverting)

• The needle enters the serosal surface, passes through the muscular layer and into (but not through) the submucosa, then exits the serosa on the same side
• Crosses the anastomosis and mirrors the same bite on the opposite side
• When tied, it inverts (tucks inward) the bowel wall, bringing serosa to serosa

• The first reliable intestinal suture technique in surgical history
• Achieves serosal apposition - the strongest healing interface in bowel
• Does not penetrate the mucosa - prevents luminal contents from contacting the suture
• Can be used as interrupted or continuous

• Bowel anastomosis (intestinal continuity restoration)
• Closure of bowel ends
• Second-layer (serosal) reinforcing suture over a mucosal closure
• Any hollow organ requiring inverting seromuscular repair

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12. Connell Suture (Inverting, Mucosal)

• A continuous suture that enters the bowel from the outside, passes through all layers including mucosa, crosses the lumen, and takes mirror bites on the opposite wall
• The bites are taken in a U-shape pattern, inverting the inner wall

• Inverts the inner (mucosal) wall of the bowel
• May include mucosa and submucosa only (inner layer only)
• Particularly useful for closing the angles of a bowel anastomosis

• Inner layer of a two-layer bowel anastomosis
• Closing angles of bowel anastomosis (corner stitches)
• Bowel closure when mucosa-to-mucosa approximation is desired with inversion
• Bladder and ureter repairs

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13. Cushing Suture

• A continuous inverting suture similar to Lembert but placed parallel to the bowel edge rather than crossing it perpendicularly
• The suture runs parallel to the wound, with each bite taken parallel to the incision line

• Creates a waterproof serosal layer over a mucosal closure
• Less inverting than Lembert - takes only serosal and muscular layers
• Produces a smooth, continuous serosal surface

• Second-layer reinforcing closure over a bowel anastomosis
• Gastric and intestinal closures requiring a watertight serosal seal
• Closure of the appendix stump

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14. Purse-String Suture

• A continuous suture placed circumferentially around the perimeter of a circular opening or defect
• When pulled tight, the edges pucker and close concentrically like the mouth of a drawstring bag

• Closes a circular defect without creating a linear incision
• Can partially or completely close depending on how tightly it is pulled
• The degree of closure depends on tissue laxity and defect size

• Inverting the appendix stump (appendectomy)
• Closing hernia sacs circumferentially
• Partial or complete closure of circular skin defects to reduce healing time (allows second-intention healing for the remainder)
• Securing ostomy appliances and tubes (e.g., gastrostomy, colostomy)
• Rectal prolapse repair

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15. Lock-Stitch Suture

• A continuous suture where every 3rd or 4th bite passes under the previous stitch rather than looping over it
• Creates a locking chain effect along the mucosal edge

• Prevents puckering of mucosal edges
• Distributes tension more evenly than a simple running suture along mucosal surfaces

• Mucosal edges in bowel anastomosis
• Situations where puckering of the anastomosis must be avoided
• Oral mucosal closure

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16. Figure-Eight Bowel Suture

• Used specifically for interrupted bowel wall closure
• The needle takes a bite on one side, crosses diagonally, takes a bite on the other side, then recrosses back to the starting side - creating a figure-8 pattern through the bowel wall

• Interrupted closure of bowel wall
• Provides strong individual approximating bites without continuous suture risk

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Quick Summary Table

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