Wound Closure – Primary Closure: Halsted’s Principles, Tension, and Techniques

Principles of Wound Reconstruction – Primary Closure

  • Objective overview- Learn Halsted’s Principles

    • Understand variables affecting wound healing

    • Understand how tension interferes with healing and techniques to combat tension

    • Become familiar with surgical techniques for closing variably shaped tissue defects

Halsted’s Principles

  • Gentle tissue handling

  • Meticulous control of hemorrhage

  • Observe strict aseptic technique

  • Preserve blood supply to tissues

  • Eliminate dead space

  • Appose tissues accurately with minimal tension

  • Historical note: William Stewart Halsted (1852–1922), 1st professor of surgery, Johns Hopkins University

Wound Closure – Why and Goals

  • Primary wound closure advantages over other techniques

    • More straightforward wound care

    • Decreased need for bandages

    • Faster resolution of the wound

    • Less pain and scarring

    • Better cosmesis and protection of underlying structures

  • Ideal approach if patient and wound qualify and client consents

  • Closure goals

    • Minimize tension

    • Return to full function (ROM, robust skin coverage)

    • Pain-free final outcome

    • Cost-effective

    • Acceptable cosmesis

    • Satisfied owner

Decision Making & Planning – Wound Factors

  • Factors to assess when planning closure- Size: may require tension-relieving closure or a skin flap for wounds > 5 cm

    • Geometric shape

    • Anatomic location

    • Chronicity

    • Bacterial load: consider culture; drain placement?

    • Structural damage: severe tissue trauma requires wound declaration before closure

    • Peri-wound status: delay closure until surrounding skin is healthy

Patient Factors and Owner Considerations

  • Species: cats have lower cutaneous perfusion and earlier wound breaking strength issues

  • Breed: tight or thin skin (e.g., Greyhounds) may complicate closure

  • Body Condition Score (BCS): > 7/9 challenges reconstruction

  • Age: older animals have reduced perfusion and slower healing

  • Temperament and owner factors- Commitment and logistical capability

    • Financial considerations

    • Cosmesis importance to owner (consider anticipated cosmetic outcome)

    • Experience and referral dynamics

Typical Closure Patterns and Suture Options

  • Fascial/Intramuscular closure (often first choice in cats)

    • Suture size: typically 3-0 or larger in fascia/intramuscular layers

    • Closure: simple interrupted or continuous

    • Suture type: monofilament absorbable (e.g., PDS = polydioxanone) is common

  • Subcutaneous (SQ) closure patterns

    • Typical sizes: 3-0 and 4-0

    • Options: Poliglecaprone-25 (Monocryl), Glycolide types such as Glycomer-631 (Biosyn), or PDS

    • Important: cats are prone to inflammatory steatitis; adding 2 extra throws increases knot volume and tissue reactivity by roughly 1.5 times

  • Intradermal/subcuticular closure

    • Size: 3-0 and 4-0 Monocryl on a cutting needle

    • Patterns: continuous horizontal, continuous vertical (including bites in SQ), and SQ-to-intradermal (final intradermal bite tied to SQ knot)

  • Cutaneous closure

    • Usually 3-0 or 4-0; 2-0 rarely used except for tie-over bands

    • Materials: Ethilon (Nylon) or Prolene (polypropylene)

  • Staples

    • Can reduce skin closure time by approximately 3 to 4-fold compared with hand suturing

    • Associated with higher infection risk in elective TPLO surgeries (Frey TN, JAVMA, 2010)

    • Staples: minimum distance between staples = 4.0 to 6.5 mm

  • Tissue adhesives (cyanoacrylate)

    • Strength: at day 1 post-op only about 15% as strong as sutured wounds

    • Not suitable for wounds under tension

    • Do not allow contact with subcutaneous tissue (SQ) due to potential foreign body reaction

  • Reference and data source

    • Data from Grier RL: Surgical sutures – Part II (Iowa State Univ Vet 34:89-92, 1972)

Suture Size Guide (Table II Concepts)

  • Skin: 4-0 to 2-0

  • Subcutaneous tissue: 4-0 to 3-0

  • Muscle: 3-0 to 2-0

  • Fascia: 3-0 to 0

  • Viscera: 5-0 to 3-0

  • Ligation of small vessels: 4-0 to 3-0

  • Ligation of large vessels: 2-0 to 1

  • Tension sutures: 2-0 to 1

  • Note: Data footnoted as data from Grier RL (1972)

Wound Healing Variables and Influences

  • Tension, pressure, and motion- Movement impairs healing

    • Proximity to a joint complicates healing

    • Self-mutilation risk

  • Patient health factors- Diabetes, Cushing’s syndrome, hypothyroidism (low T4), immunosuppression, cancer

  • Perioperative considerations- Ensure systemic health supports healing

Tension and Its Management

  • Too much tension

    • Do not close by direct edge approximation if it will cause ischemia from suture pressure

    • On the extremities, excessive tension can create a biologic tourniquet effect

  • Tension lines and wound planning

    • Skin tension lines reflect the direction of pull from cutaneous muscles and gravity

    • Much of skin’s connective tissue orients parallel to these lines

    • Closure parallel to tension lines reduces closure tension

  • Assessing tension in practice

    • Position the animal in a natural standing position

    • Tent the peri-wound skin and explore closure directions by moving skin

    • The optimal closure direction is the one with the least tension

    • Use established tension line patterns as a frame of reference (Tobias & Johnson: Veterinary Surgery: Small Animal, Saunders/Elsevier, 2012)

  • Incisions and tension lines

    • Incisions across tension lines tend to gape and require more sutures

    • Ideal: incisions parallel to skin tension lines

  • Exceptions

    • Some cases permit closing perpendicular to tension lines on extremities as exceptions to the general rule

Techniques to Relieve Tension

  • Undermining (the primary relaxation technique)

    • Use metzenbaum scissors to undermine skin and SQ or skin and panniculus muscle to release attachments

    • Blunt technique (blunt blades closed): opening the blades or using a blunted scalpel handle

    • Sharp technique (blades open to closed): snipping tissue as blades advance; more appropriate in extremities

    • Most common to combine blunt and sharp dissection

  • Undermining benefits and cautions

    • Draws upon the skin’s elastic potential for closure

    • Peri-wound skin must be healthy and pliable for blood supply, inflammation, and edema considerations

    • The undermining process elevates the direct cutaneous vessel with undermined skin, preserving blood supply to the deep subdermal plexus

    • Plexuses arborize to perfuse the dermis through superficial plexi

    • Important note: creating dead space is an intentional consequence of undermining

  • Tension-relieving suture patterns

    • Mattress sutures

    • Vertical mattress: can cause edge eversion but acceptable

    • Horizontal mattress: risk that the horizontal component may compromise blood supply; not ideal

    • Pattern variations

    • Far-Far-Near-Near

    • Far-Near-Near-Far- Far: about 1 cm from the wound edge

      • Near: about 5 mm from the wound edge; apposes rather than everts

    • Knot placement and technique

    • Do not place knots directly over the incision

    • Can intersperse mattress sutures with simple interrupted sutures

    • Use with rubber stents if needed to prevent tissue strangulation

  • Releasing (Relaxing) Incisions

    • Create relaxing incisions near the defect to allow skin apposition

    • After undermining, consider unilateral or bilateral simple relaxing incisions adjacent to the wound

    • Can be planned after preplacing a continuous subcuticular suture pattern

    • Multiple punctate incisions can be made parallel to the wound to facilitate closure

Summary of Practical Guidelines

  • Before closure, evaluate whether primary closure is feasible with minimal tension

  • If tension is excessive, apply tension-relieving strategies (undermining, releasing incisions, tension-relieving sutures)

  • Choose closure patterns appropriate to tissue type, location, and patient factors

  • Be mindful of the risk of dead space; manage with undermining and appropriate suturing patterns

  • Consider cosmetic and owner expectations when choosing closure technique

  • Maintain strict asepsis and preserve tissue vascularity to promote healing

References and Notes

  • Tobias & Johnson Veterinary Surgery: Small Animal Reference (20014 edition cited as basis for tension line framework)

  • Frey TN, JAVMA 2010: Ptacle data on staples and infection risk in elective orthopedic procedures (TPLO)

  • Table II: Guide for selecting suture size (data derived from Grier RL, Surgical sutures – Part II, Iowa State Univ Vet, 1972)

  • Practical takeaways: parallel incisions to tension lines minimized; avoid edge ischemia; undermining preserves deep subdermal blood supply while creating necessary dead space for flap design