Senior pets undergo surgery more frequently than younger ones age brings a higher burden of tumors, orthopedic disease, and organ conditions requiring surgical management. And yet age-related tissue changes make wound closure more technically demanding in precisely the patients who also tolerate complications least well.

Understanding what changes with age in the tissue helps explain why closure technique must be adjusted for geriatric patients.

Quick answer: Geriatric dogs and cats present four specific closure challenges: thinner, less elastic skin that tears at suture entry points; delayed healing from reduced perfusion and immune function; comorbidities (diabetes, hyperadrenocorticism, CKD) that impair healing independently; and reduced collagen synthesis that weakens tissue intrinsic strength. Closure modifications include: PDS preferred over faster-absorbing materials to match extended healing timelines, smaller needle sizes, cruciate or horizontal mattress patterns instead of simple interrupted in fragile skin, intradermal closure to eliminate licking targets, and extended suture removal timing (full 14 days or beyond).

Key takeaways

• Feline and canine skin becomes thinner and less elastic with age, increasing cut-through risk at suture entry points.
• PDS is preferred in geriatric patients because delayed healing requires longer-duration tensile strength.
• Intradermal absorbable closure eliminates the removal visit stress and licking target for older pets.
• Cruciate or horizontal mattress patterns distribute bite force more broadly in fragile skin.
• Comorbidities (diabetes, Cushing's, CKD) significantly impair healing independently of the closure technique.
• Suture removal extends to 14 days or beyond in geriatric patients with slow wound healing.

Four age-related tissue changes that affect closure

1. Thin, inelastic skin

Older dogs and cats undergo dermal thinning with age. Collagen cross-linking changes make the dermis less elastic and more prone to tearing. A suture placed 4 to 5 mm from the wound edge in young tissue holds reliably; in thin geriatric skin, it may cut through at the entry point under tension.

This is the same mechanism that explains suture cut-through in fragile or inflamed tissue and the same modifications apply: cruciate or horizontal mattress patterns over simple interrupted, smaller needle sizes, and wider spacing between sutures to reduce focal stress concentration.

Practical modification: consider cruciate sutures instead of simple interrupted for skin closure in geriatric patients, particularly in cats over 12 years and large breed dogs over 8 to 9 years.

2. Delayed wound healing

Wound healing depends on adequate perfusion (to deliver immune cells, oxygen, and nutrients) and immune function (to control contamination and drive the repair phase). Both decline with age.

The implications for closure timing:

• The repair phase takes longer to build tensile strength
• Sutures may be needed for the full 14-day window rather than the shorter end (10 to 12 days feasible in young, healthy patients)
• The risk of premature suture removal is higher

Practical modification: schedule recheck at day 14 rather than day 10 to 12 for geriatric patients. If wound healing appears delayed at the recheck, defer suture removal by 3 to 5 additional days.

For suture removal timing modified for geriatric cats, see suture removal timing in geriatric cats. For dogs, see suture removal timing in geriatric dogs.

3. Comorbidities

Diabetes mellitus, hyperadrenocorticism (Cushing's disease), chronic kidney disease, and hypothyroidism each impair wound healing through distinct mechanisms:

Geriatric patients should have pre-operative bloodwork and a cardiovascular assessment before elective surgery. Uncontrolled diabetes or Cushing's disease substantially increases wound complication risk and should ideally be managed before elective procedures.

4. Reduced collagen synthesis

Collagen is the primary structural protein in healed wounds. Its synthesis rate and quality decline with age. The result: the healed wound is intrinsically weaker at the same timepoint compared to a wound in a younger patient.

Practical modification: longer-duration absorbable sutures (PDS rather than Monocryl for deep layers in geriatric patients with any delay in expected healing) provide extended structural support through the slower healing process.

Suture material modifications

Deep layers: PDS preferred over faster-absorbing alternatives

PDS (polydioxanone) retains significant tensile strength for 4 to 6 weeks and absorbs over 180 to 210 days. In a healthy young dog, this is more duration than needed for fascial healing. In a geriatric patient with delayed healing, it is appropriate.

Monocryl (poliglecaprone 25) loses most of its strength by 21 days. In a geriatric patient whose linea alba is healing slowly, the suture may lose functional strength before the tissue has adequate intrinsic strength to compensate.

Skin: intradermal absorbable over external non-absorbable

Two specific advantages in geriatric patients:

No removal visit: older patients particularly cats are stressed by veterinary visits. An intradermal closure eliminates the removal visit entirely.

No external licking target: geriatric dogs and cats may be less consistent E-collar users, and their owners may be less strict about compliance. Removing the external suture material eliminates the most common source of self-trauma.

For how intradermal closure works in this context, see intradermal closure in older dogs.

Pattern modifications

Cruciate or horizontal mattress over simple interrupted

When tissue is fragile and sutures are at risk of cutting through, the cruciate pattern distributes the bite force differently and is significantly faster to place (JAVMA 2016 data). Horizontal mattress sutures spread tension across 8 to 10 mm from each wound edge, further reducing focal stress.

Specific indication in geriatric patients: cats over 12 years with hyperadrenocorticism, Cushing's-treated dogs with thinned skin, any patient where simple interrupted sutures are pulling through the tissue at placement.

Wider spacing

Reducing suture spacing (more sutures per wound length) might seem protective, but it increases the total number of suture-skin interface points each one a potential cut-through site. Wider spacing with an appositional pattern that distributes tension is often more appropriate.

For how these pattern modifications compare in the context of high-tension and fragile-tissue closure, see pattern modifications for fragile skin.

Obese geriatric patients: compounded challenges

Obesity and aging frequently coincide in middle-to-senior-aged dogs and cats. The combined effect:

• Reduced perfusion (fat is poorly vascularized)
• Greater dead space (more fat tissue to approximate)
• Higher skin tension (weight on the wound)
• Both thin skin (age) and thick subcutaneous fat (obesity)

For how obesity specifically affects closure technique, see closure considerations in obese dogs.

Post-operative monitoring: more frequent and more important

What to monitor

The monitoring frequency and detail appropriate for geriatric patients is greater than for young, healthy patients:

• Twice-daily wound checks
• Document changes over time (photograph the wound at each check)
• Watch for systemic signs geriatric patients developing wound infections may show systemic signs (lethargy, inappetence, fever) before local signs become obvious
• Check suture integrity specifically suture cut-through, loosening, or loss is more likely in geriatric patients

Nutrition during recovery

Collagen synthesis requires adequate dietary protein. Geriatric patients with reduced appetite or pre-existing protein restriction (for CKD management) may have compromised wound healing from nutritional factors. Discuss any feeding changes with your vet before and during recovery.

For the post-operative monitoring protocol applicable to geriatric patients, see post-operative monitoring in geriatric patients.

Frequently asked questions

My 14-year-old cat is having a mass removed. Are older cats at higher risk for wound complications?

Yes, but manageable risk. The key factors are: the cat's overall health status, whether comorbidities are controlled, the size and location of the mass, and the closure technique chosen. An experienced vet will adjust the technique for a geriatric patient, choosing materials and patterns that match the tissue's actual properties. Careful pre-operative assessment, appropriate anesthesia monitoring, and attentive post-operative care reduce this risk substantially.

My older dog's wound opened two days after surgery. Is age the cause?

Possibly, but other factors are equally likely: E-collar non-compliance (allowing licking), premature activity, excessive wound tension at closure, or concurrent illness. Age-related healing delay typically manifests as very slow progress over 7 to 14 days, not sudden acute failure in the first 48 hours. A wound opening in the first 2 days most often reflects one of the other factors.

Should my senior dog get intradermal sutures specifically?

It is worth discussing with your vet. The main advantages for senior dogs are: no removal visit (less stress), no external material to lick (reduces E-collar dependence), and finer healed scar. The main requirement is that the wound must be low-to-moderate tension and clean for intradermal closure to be appropriate. Many routine procedures in geriatric dogs meet these criteria.

Geriatric closure requires adjusting every assumption that applies to a young, healthy patient. The healing timeline is longer. The tissue tolerates suture entry points less well. The comorbidities stack against normal wound healing. Each modification PDS instead of Monocryl for deep layers, cruciate instead of interrupted for fragile skin, intradermal instead of external for skin is a response to a specific age-related change in what the tissue can support.

Resources

• Clinician's Brief. How to Fine-Tune Suture Choices for Today's Veterinarian. cliniciansbrief.com
• VCA Animal Hospitals. Care of Surgical Incisions in Cats. vcahospitals.com
• JAVMA 2016 (Kieves et al.). Comparison of Tensile Strength Among Simple Interrupted, Cruciate, Intradermal, and Subdermal Suture Patterns in Ex Vivo Canine Skin. pubmed.ncbi.nlm.nih.gov

Not every dog needs the same skin closure. Some can tolerate external sutures perfectly well. Others lick obsessively, are poor candidates for return recheck visits, or have wounds where cosmetic outcome genuinely matters.

Subcuticular closure is the option that eliminates those problems. The sutures run beneath the skin surface, there's nothing external to target or remove, and the healing scar is typically finer and less visible.

The question is not whether subcuticular closure is good it is. The question is when it's the right choice for a specific dog, wound, and situation.

Quick answer: Subcuticular closure is best suited for clean, straight, low-tension incisions in dogs where cosmetic outcome is a priority, recheck compliance for suture removal may be limited, or the dog is a known licker. Absorbable monofilament sutures (4-0 Monocryl) placed in a continuous horizontal pattern within the dermis provide adequate holding strength without requiring removal. It is not appropriate for high-tension wounds or contaminated fields without a tension-reducing subcutaneous layer placed first.

Key takeaways

• Subcuticular closure runs horizontally within the dermis, just below the skin surface.
• No suture removal is needed when absorbable materials are used, reducing recheck visits.
• Best suited for clean, straight, low-tension incisions after adequate subcutaneous closure.
• Not appropriate as a standalone closure in high-tension or contaminated wounds.
• 4-0 Monocryl is the most studied material for subcuticular closure in dogs.
• The subcutaneous layer must be closed first to eliminate dead space before subcuticular placement.

What subcuticular closure is

Subcuticular closure (also called intradermal closure) places a continuous suture horizontally within the dermis, just below the epidermal surface. The needle alternates sides of the wound with each pass, advancing along the length of the incision.

The result: wound edges are drawn together from within, with no suture material visible at the surface and no external knots.

This is distinct from subcutaneous closure, which closes the deeper fat layer. The two terms sound similar but refer to different tissue layers:

For how subcutaneous closure differs from subcuticular closure, see subcutaneous closure that precedes subcuticular.

When subcuticular closure is the right choice

Patients who lick persistently

External sutures are a target. Dogs that persistently lick or chew wound sites can remove traditional sutures within hours of coming home. Subcuticular sutures are entirely buried and cannot be accessed without penetrating the skin.

This is the strongest practical indication for subcuticular closure in dogs.

When recheck compliance is uncertain

Subcuticular closure with absorbable sutures (Monocryl) requires no removal. For owners who may have difficulty returning for a suture removal appointment, this eliminates a step that is otherwise non-negotiable.

Cosmetically sensitive areas

Wounds on the face, lateral body, or areas visible to the owner may benefit from subcuticular closure. The intradermal pattern produces a finer scar with less inflammatory response from suture tracts compared to external sutures.

Published research (PMC9960444, Veterinary Sciences 2023) confirms that subcuticular closure "promotes epithelialization due to adequate skin apposition and minimal skin tension" and avoids "formation of percutaneous suture tracts" that can cause visible scarring.

After spay, mass removal, or biopsy

Elective, clean procedures with straight incisions are the ideal setting for subcuticular closure. These wounds carry low infection risk and predictable tension, making the technique reliable and appropriate.

For a broader view of where subcuticular closure fits within skin closure options, see subcuticular closure within skin closure options.

When subcuticular closure is not appropriate

Subcuticular closure is not universal. The technique has specific limitations:

High-tension wounds: subcuticular sutures are not tension-relieving. Without adequate subcutaneous closure reducing tension, the subcuticular layer cannot hold the skin edges against significant pull. Mattress or interrupted patterns with good tissue purchase are needed instead.

Contaminated or infected wounds: burying suture material in a contaminated field risks trapping bacteria. External closure with interrupted sutures allows individual suture removal if infection develops at a specific point.

Irregular wound edges: the continuous horizontal pattern produces best results on straight, linear incisions. Curved or irregular wounds are difficult to close evenly with subcuticular sutures.

Without prior subcutaneous closure: subcuticular sutures depend on the subcutaneous layer doing the structural work. Placing subcuticular sutures without first closing the subcutaneous fat leaves the intradermal suture under too much tension.

For the cosmetic benefits of subcuticular closure in appropriate cases, see cosmetic benefits of subcuticular closure.

Suture material for subcuticular closure in dogs

First choice: 4-0 Monocryl (poliglecaprone 25)

Multiple published studies confirm Monocryl as the top-performing material for subcuticular closure in dogs:

• PMC9960444: Monocryl achieved better cosmetic scores than polypropylene in head-to-head comparison
• PMC8614295: Monocryl outperformed Caprosyn (polyglytone 6211) in cosmetic, clinical, and histological evaluations

Why monofilament materials work best:

• Low tissue drag as the suture passes through the dermis
• Minimal bacterial wicking compared to braided sutures
• Consistent absorption timeline (90 to 120 days for Monocryl)

For intradermal closure technique details specific to dogs, see intradermal closure as a related technique.

The technique in brief

Subcuticular closure follows subcutaneous closure and proceeds as follows:

1. Start 5 mm from one wound end, bury the knot in the subcutaneous tissue
2. Pass the needle horizontally through the dermis on one side, 2 to 3 mm below the skin surface
3. Cross to the opposite side and take a parallel bite at the same depth
4. Advance 5 mm along the wound length and repeat
5. End 5 mm past the wound edge and bury the final knot

Key technical rules:

• Bites taken too shallow pierce the epidermis (visible suture)
• Bites taken too deep enter fat rather than dermis (ineffective pattern)
• Even tension at each bite prevents dog-ear deformity at wound ends

What owners need to know post-surgery

No removal appointment: if absorbable sutures were placed, there is nothing to take out. The suture dissolves over 90 to 120 days.

What you will see: a thin incision line without visible stitches. A slight ridge or firmness along the line may be palpable for 2 to 4 weeks as the suture absorbs.

What you still need to do:

• Keep the E-collar on until the vet confirms it can come off
• Restrict activity for the full prescribed period
• Check the wound twice daily for swelling, discharge, or gaping

Even with buried sutures, licking at the wound surface disrupts healing tissue at the epidermal layer. The E-collar is not optional.

Frequently asked questions

Is subcuticular closure stronger than external sutures?

At placement, approximately equivalent. The pattern's clinical advantage is not superior strength it is the elimination of external suture material that can be licked, chewed, or infected. The holding strength depends primarily on the subcutaneous layer, not the skin closure.

My dog had subcuticular closure and the incision looks slightly raised. Is that normal?

Yes. A small, firm ridge along the incision is common in the first 2 to 4 weeks. This is the suture material within the dermis and the normal inflammatory healing response. It gradually softens. If the ridge is soft and fluctuant (fluid-filled), contact your vet, as this may indicate a seroma.

Can I use subcuticular closure techniques at home for small cuts?

No. Subcuticular suture placement requires surgical instruments, proper suture material, sterile technique, and the technical skill to place sutures at the correct depth within the dermis. All wound closure in dogs beyond minor cuts should be assessed and performed by a veterinarian.

Subcuticular closure earns its place when the situation calls for it: the persistent licker, the cosmetically sensitive wound, the owner who can't return for a removal appointment. Used appropriately on clean, low-tension incisions with proper subcutaneous support, it reliably delivers excellent cosmetic healing without the compliance challenges of external sutures.

Resources

• PMC (Veterinary Sciences, 2023). Comparison of Absorbable and Nonabsorbable Sutures for Intradermal Skin Closure in Dogs. ncbi.nlm.nih.gov
• PMC (Veterinary Sciences, 2021). A Controlled Trial of Polyglytone 6211 versus Poliglecaprone 25 for Intradermal Suturing in Dogs. ncbi.nlm.nih.gov
• Veterinary Surgery Online. Intradermal Skin Closure. vetsurgeryonline.com
• WCVM University of Saskatchewan. Lab 6 Part 4: Incision Closure. wcvm.usask.ca

Emergency surgery closure is not simply faster elective surgery closure. The patient's physiological state coagulopathy, hypothermia, acidosis, hemodynamic instability shapes every closure decision in ways that have no equivalent in a planned, stable procedure.

The core principle is this: do what is necessary to keep the patient alive, defer everything else to a second surgery when the patient can tolerate it.

Quick answer: Emergency abdominal surgery closure follows a spectrum: standard layered closure when the patient is stable enough to tolerate it; damage control surgery (abbreviated technique prioritizing hemorrhage control and contamination reduction, temporary closure, definitive repair 24 to 48 hours later) when the patient is hemodynamically unstable. MSPCA-Angell: "Phase 2 is the first surgery where the primary goal is to limit severe hemorrhage and control bowel leakage. No attempt is made to reconnect discontinuous sections of bowel that would be done at the second definitive surgery."

Key takeaways

• Damage control surgery (DCS) prioritizes hemorrhage control and contamination reduction over complete anatomical repair.
• Temporary abdominal closure is used when definitive closure cannot be safely performed in an unstable patient.
• Definitive surgery follows 24 to 48 hours later, once the patient is hemodynamically stable.
• Contaminated wounds from GI spillage, uroabdomen, or bite wounds require delayed primary closure principles even in emergency contexts.
• Continuous suture patterns are used in damage control to minimize time while achieving adequate contamination control.
• Standard layered closure is used when the emergency patient is sufficiently stable to tolerate full anesthetic time.

The stability spectrum: how it determines closure

Hemodynamically stable emergency patient

Some emergency patients a GI foreign body obstruction without perforation, a splenic mass removed before rupture, a planned exploratory for a suspected obstruction arrive in or can be stabilized to a state that allows complete anatomical repair.

For these patients, standard layered closure proceeds:

• Hollow organ closure with inverting patterns (Cushing, Lembert) if enterotomy was performed
• Abdominal wall closure with PDS or equivalent in simple continuous
• Subcutaneous closure with Monocryl or Vicryl
• Skin closure with interrupted nylon or intradermal Monocryl

These closures follow the same protocol as equivalent elective procedures. The emergency designation describes the urgency of the decision to operate, not necessarily a modification of technique.

Hemodynamically unstable emergency patient

The lethal triad of trauma acidosis, coagulopathy, and hypothermia creates a physiological state incompatible with prolonged surgery. Every additional minute under anesthesia risks coagulation failure, cardiac arrest, or irreversible multi-organ injury.

MSD Veterinary Manual: "Damage control surgery is a limited laparotomy designed only to control hemorrhage and/or to minimize contamination but not to perform definitive surgical repair, to avoid similar clinical complications. Definitive care is delayed until the patient is able to tolerate extended anesthesia and surgery."

Damage control surgery: the three-phase approach

MSPCA-Angell (Damage Control Surgery: Is There a Role in Veterinary Medicine?):

Phase 1: Pre-operative stabilization

• Limit hemorrhage
• Manage hypothermia
• Transfuse blood products to correct coagulopathy
• Get the patient to the operating room as quickly as safely possible

Phase 2: Damage control laparotomy

• Control hemorrhage (pack the abdomen with laparotomy pads, ligate major bleeding vessels)
• Reduce contamination (rapid running suture closure of identified bowel leaks; do not attempt full anastomosis)
• "Identified lesions are rapidly sutured in running/continuous suture pattern to reduce contamination"
• Urinary diversion if bladder or urinary tract rupture is present (urinary catheter, Jackson-Pratt drain)
• Temporary abdominal closure leave laparotomy pads in place for compression if needed
• Do not attempt bowel reconnection

Phase 3: Definitive surgery (24 to 48 hours later)

• Re-enter the abdomen once the patient has achieved hemodynamic stability
• Perform complete anatomical repair (bowel anastomosis, permanent organ repair)
• Definitive abdominal wall closure

VetEducation: "Definitive surgical repair should take place following patient stabilisation, and usually occurs 24 to 48 hours following damage control surgery."

For how the delayed primary closure principles apply after damage control, see delayed closure in emergency context.

Temporary abdominal closure

When the abdomen must be left open between damage control and definitive surgery, a temporary closure barrier is applied.

Purpose: prevent evisceration, limit contamination, allow abdominal decompression if needed.

Technique: a sterile barrier (damp laparotomy pads, sterile plastic sheeting, or negative-pressure dressing) is placed over the abdominal contents, then the skin is loosely approximated with large interrupted sutures or towel clamps. This is not a wound closure it is a controlled open abdomen.

MSPCA-Angell: "The abdomen is then left open with a temporary closure or barrier to limit contamination."

GI contamination: closure decisions after bowel leakage

Bowel spillage into the abdominal cavity creates a contaminated environment. Closure decisions must account for this regardless of whether the procedure is elective or emergency.

Intraoperative spillage during elective surgery: lavage the abdomen thoroughly, consider drain placement, proceed with standard closure. The contamination was controlled during the procedure.

Pre-existing peritonitis (e.g., GI perforation before surgery): the contamination is established. After bowel repair or resection, abdominal lavage is performed (warm saline), a drain is placed (Jackson-Pratt or closed suction), and the abdomen is closed over the drain. In severe cases of septic peritonitis, open abdominal management may be preferred.

DVM360: "Drainage of the abdomen may be indicated in cases such as septic peritonitis and bile peritonitis. In cases of septic peritonitis in small animals, the mortality rate is 30 to 50%."

For how contamination principles shape the full closure decision in wound management, see contaminated wound closure principles.

Uroabdomen and bile peritonitis: specific closure considerations

Uroabdomen (bladder or urinary tract rupture):

• Surgical repair of the rupture site using a simple continuous absorbable suture
• Urinary catheter placement for bladder decompression post-repair
• Closed abdominal drain for residual urine or ongoing minor leakage
• Standard layered abdominal wall closure once the source is controlled

Bile peritonitis:

• Cholecystectomy or biliary repair depending on the source
• Copious abdominal lavage
• Closed abdominal drain
• Patients with bile peritonitis have significant systemic consequences (inflammation, coagulopathy) the closure decision must account for the patient's metabolic state

Skin and body wall closure in emergency surgery: practical considerations

Time under anesthesia: every additional layer of closure adds anesthetic time. In an unstable patient, subcutaneous closure may be simplified or omitted if it would extend surgery time dangerously.

Contaminated skin wounds (trauma cases): bite wounds, degloving injuries, and penetrating trauma present to emergency rooms as contaminated. Do not close these wounds primarily. Manage open with daily wound care and delayed primary closure at day 3 to 5.

For how common closure errors apply in emergency settings, see closure errors in emergency cases. For the wound closure principles that underpin emergency closure decisions, see principles of wound closure in emergency context.

What owners need to understand about emergency surgery recovery

Surgery may have been abbreviated: if your pet underwent damage control surgery, a second procedure is planned. The first surgery controlled the immediate life threat; the second surgery completes the anatomical repair.

Recovery timeline is less predictable: unlike elective surgery with known procedure scope, emergency cases may have ongoing fluid losses, infection risks, or metabolic instability that extend the recovery compared to a comparable elective procedure.

Drains: emergency cases more frequently require drains for abdominal or wound fluid management. These are typically removed within 3 to 7 days but will be assessed at each recheck.

For the post-operative monitoring that follows emergency closure, see post-op monitoring after emergency surgery closure.

Frequently asked questions

My dog had emergency abdominal surgery and the vet mentioned a possible second surgery. Does that mean something went wrong?

Not at all. In some cases, damage control surgery is the planned approach controlling the most critical problem (hemorrhage or GI contamination) while the patient is too unstable for complete repair. The second surgery is part of the protocol, not a complication. Your vet should have explained this plan.

The vet said they "closed the abdomen quickly." Does that mean the closure is inadequate?

Rapid closure in an emergency does not mean inadequate closure. A skilled surgeon can perform a sound abdominal wall closure quickly using continuous suture technique. "Quickly" refers to the overall surgical time being limited by the patient's stability, not to cutting corners on the structural closure.

My cat had emergency abdominal surgery and there is a drain coming from the wound. How long will it stay?

Drains after emergency abdominal surgery typically remain for 3 to 7 days, depending on output and the underlying condition. For septic peritonitis, drains may remain longer. Drain output is assessed at each recheck decreasing volume and clearer color (from bloody to clear serous) indicate the drain is ready for removal.

Emergency closure strategy is defined by one constraint: what can this patient safely tolerate right now? Standard layered closure when the patient is stable. Damage control when they are not. Temporary closure when even damage control cannot be completed safely. In every case, the goal is the same get the patient out of the operating room alive, then finish the repair when they can survive the finishing.

Resources

• MSPCA-Angell. Damage Control Surgery: Is There a Role in Veterinary Medicine? mspca.org
• VetEducation. Damage Control Surgery for Traumatic Haemoabdomen in Dogs and Cats. veteducation.com
• MSD Veterinary Manual. Trauma in Emergency Medicine in Small Animals. msdvetmanual.com
• DVM360. Drains: Proper Use and Management. dvm360.com

Large breed dogs present a specific wound closure challenge: when skin is removed or lost over the trunk, there is often not enough laxity to simply pull the edges together. Pulling too hard creates tension. Tension causes ischemia. Ischemia causes dehiscence.

Walking sutures solve this by redistributing the tension before the skin edges ever come together.

Quick answer: Walking sutures are subcutaneous sutures that anchor the dermis to the underlying fascia at intervals along a wound, advancing skin progressively toward the defect with each placement rather than attempting to close the full gap in one pull. DVM360 (Swaim) describes them as "tension-type sutures that can be used to close large skin defects in areas where sufficient skin surrounds the wound." Standard material: 2-0 PDS or Biosyn (3-0 in patients under 15 kg). Particularly indicated for trunk and lateral thorax wounds in large dogs.

Key takeaways

• Walking sutures anchor dermis to fascia at intervals, advancing skin progressively toward the wound center.
• Primary indication: large trunk and lateral thorax skin defects in dogs where direct closure would create excessive tension.
• Standard material: 2-0 PDS or Biosyn; 3-0 in patients under 15 kg.
• Staggered removal protocol: remove every other suture at day 10, remaining sutures at day 14.
• Thorax wounds require respiratory monitoring tight closure can impair breathing in smaller patients.
• Not appropriate over skin flaps walking sutures risk damaging the blood supply to the flap.

What walking sutures do

A walking suture does not close the wound at the skin surface. It anchors the dermis to the fascia beneath the skin, pulling the skin toward the defect from underneath.

DVM360 (Dr. Steven Swaim, reconstructive surgery techniques): "Walking sutures are tension-type sutures that can be used to close large skin defects in areas where sufficient skin surrounds the wound that can be moved or stretched to close the wound. These sutures are primarily indicated for closing skin defects on the trunks of small animals."

Veterinary Surgery Online: "Walking sutures can be used to tack down the dermis to the underlying fascia. These also help decrease tension on the wound edges. After placement, the wound edges should be in close proximity and under minimal tension."

Each walking suture placed advances the skin a small distance. Placed sequentially from the wound edges inward, they bring the skin incrementally closer to the defect center with each stitch hence "walking" the skin across.

When walking sutures are used

Primary indication: large trunk skin defects

• Mass excisions on the lateral thorax or abdomen requiring wide margins
• Degloving injuries where skin was lost over the trunk
• Wounds too large for simple closure but with adequate adjacent skin for advancement
• Cases where a skin flap or graft is not available or not planned

DVM360 (Swaim): "Most large skin defects on the trunks of dogs and cats can be closed with walking sutures, either using the technique described here or a modification of it. These sutures advance local skin to close large defects without requiring additional incisions to create flaps or attain relaxation."

When walking sutures cannot fully close the wound

If the defect is too large for complete walking suture closure, the technique closes the wound as much as possible, then allows the remainder to heal by second intention or stages it for a secondary surgery.

Veterinary Surgery Online: "If a wound is too large to be closed completely using this technique, it can be closed enough to allow the remainder of the wound to heal by second intention or with a secondary surgery."

Contraindication: skin flaps

Today's Veterinary Practice (Caudal Superficial Epigastric Flap technique notes): "I prefer not to tack down or use walking sutures in the subcutaneous tissues to attempt to reduce motion and dead space under the flap and inguinal region. These sutures could inadvertently damage the blood supply to the flap."

For how tension-relieving sutures are used for high-tension surgical wounds generally, see tension-relieving sutures alongside walking sutures.

Technique overview

Bite placement:

• The needle passes through the dermis on one side of the advancing skin edge
• Then through the superficial fascia at the target location (where that skin edge should end up)
• Tied the skin edge advances to meet the fascia at that point
• The next suture is placed in the adjacent skin, advancing the next section

Pattern sequence:

• Begin at the wound margins and work inward
• Each suture advances one section of skin; sequential sutures advance the whole leading edge
• After all walking sutures are placed, the wound edges should be in close proximity or apposed

Final skin closure:Placed after all walking sutures. Standard options: 3-0 to 4-0 Prolene or nylon (interrupted), or skin staples for speed.

Suture material for walking sutures

Veterinary Surgery Online: "Typically, walking sutures and muscle fascia sutures are applied using 2-0 PDS or Biosyn (3-0 in patients under 15 kg, or occasionally 0 in larger dogs). Subcutaneous tissues closed using 3-0 PDS, Biosyn, or Monocryl (4-0 in smaller patients). Dermal closure performed using 3-0 Monocryl or Biosyn (4-0 in smaller patients)."

PDS and Biosyn are monofilament absorbable materials with adequate strength retention for the 3 to 4 weeks needed while the tissue planes adhere and the skin advances fully. They are preferred over braided absorbable materials in the subcutaneous plane because of lower infection risk.

For how suture size relates to patient weight in this context, see suture size selection for walking sutures.

Thorax wounds: a specific caution

Tight closure of thorax skin restricts the chest wall's ability to expand. DVM360 (Swaim): "Keep in mind that tight skin closure on the thorax can impair respiration, especially in smaller animals. Therefore, thorough preoperative assessment and special care during closure should be taken to avoid this complication."

This is most relevant in patients under 10 to 15 kg and in wounds over the mid-lateral or dorsal thorax. The surgeon must assess respiratory function after closure and before recovery from anesthesia.

Suture removal protocol

Walking sutures use a staggered removal schedule to prevent the wound from reopening as tension redistributes during healing:

DVM360 (Swaim): "Remove every other suture (half the sutures) 10 days after surgery. Remove the remaining sutures after 14 days."

This staggered approach maintains some mechanical support while allowing the earlier-placed sutures to be assessed. If the wound looks precarious at day 10, the vet may delay removing any sutures at that visit.

For how suture removal timing applies to walking suture cases, see suture removal timing in high-tension closures.

What to monitor at home

Days 1 to 10:

• Swelling or firmness along the suture line is normal as the skin advances and adheres
• Discharge should be minimal serosanguinous (slightly blood-tinged watery) discharge is expected in small amounts; purulent or copious discharge is not
• The wound line may look "bunched" immediately after surgery this is expected as the skin advances and will flatten during healing

Signs requiring contact with your vet:

• Wound edges separating
• Increasing redness extending beyond the wound margins
• Wound discharging pus
• Patient showing respiratory changes (for thorax wounds)

For how dead space management intersects with walking suture technique, see dead space management alongside walking sutures. In obese dogs, walking sutures are especially valuable for managing the thick subcutaneous fat layer; see walking sutures in obese dog closure.

Frequently asked questions

My large dog had a mass removed and the vet used "walking sutures." Why not just standard sutures?

Standard closure sutures are placed at the skin surface and close the gap by pulling the edges together. In large wounds, that pull creates ischemia-inducing tension. Walking sutures move the skin toward the gap at the subcutaneous level first, so by the time skin closure sutures are placed, the edges are already close together and under minimal tension.

Are walking sutures the same as tension sutures?

Related but not identical. Walking sutures advance skin by anchoring dermis to fascia progressively. Tension-relieving sutures (mattress, far-near-near-far) redistribute tension across a wider surface area of an existing closure. Both reduce tension but through different mechanisms and at different stages of wound closure.

The wound looks wrinkled and bunched after my dog's surgery. Is that a problem?

Not usually. When skin is advanced toward a defect using walking sutures, the surrounding skin gathers slightly before it redistributes. This bunching typically resolves over 5 to 10 days as the skin stretches and adheres. If the wrinkling is accompanied by redness, warmth, or discharge, contact your vet.

Walking sutures do something the skin surface cannot: they move the wound edges before the skin is asked to span a gap under tension. In large breed dogs with significant trunk defects, they are the difference between a closure that holds and one that dehisces in the first week.

Resources

• DVM360 (Dr. Steven Swaim). Skills Laboratory: Reconstructive Surgery Techniques, Part 5: Walking Sutures. dvm360.com
• Veterinary Surgery Online. Wound Closure Continued. vetsurgeryonline.com
• Today's Veterinary Practice. Caudal Superficial Epigastric Flap. todaysveterinarypractice.com
• WSAVA 2007 (VIN). Reconstructive Surgery. vin.com

Before the skin is touched, several critical layers beneath it need to be properly closed. Muscle closure is one of the most structurally important steps in any abdominal or orthopedic surgery. Get it wrong, and the consequences are serious: herniation, dehiscence, or permanent loss of abdominal wall integrity.

For owners, understanding this step helps explain why your vet takes closure seriously and why post-operative rest is non-negotiable.

Quick answer: Muscle layer closure uses absorbable monofilament sutures (typically PDS or Biosyn) placed in a simple continuous or interrupted pattern. The linea alba (the fibrous midline band between the abdominal muscles) is the critical holding layer in abdominal closure. Sutures must incorporate fascia, not just muscle belly, to achieve adequate strength. Proper muscle closure prevents herniation, infection, and wound dehiscence.

Key takeaways

• The linea alba is the primary holding layer in abdominal closure, not the muscle belly itself.
• PDS (polydioxanone) is the preferred material for muscle and fascial layers in small animals.
• Simple continuous pattern is standard for linea alba closure in most soft tissue surgeries.
• Suture bites must incorporate fascia, not just muscle, or dehiscence risk increases significantly.
• Excessive tension strangulates tissue and delays healing despite technically adequate closure.
• Hernia is the most serious consequence of inadequate muscle layer closure.

Why muscle layer closure matters

Muscle and fascia form the structural wall of the abdomen. When an incision opens this wall for abdominal surgery, it creates a defect that the body cannot close on its own in the correct anatomical configuration.

Without proper suture closure:

• Abdominal organs can herniate through the gap
• Dead space forms where fluid and bacteria accumulate
• The skin closure must bear all of the wound tension, increasing dehiscence risk

Veterian Key (Surgery of the Abdominal Cavity) states: "Make sure to incorporate fascia in the linea closure. Because the holding layer of abdominal incisions consists of fascia rather than muscle, dehiscence is common if the rectus fascia is not incorporated in sutures."

The linea alba: the critical holding layer

The linea alba is a white fibrous band running along the ventral midline of the abdomen. It is formed by the interdigitation of fascial sheaths from the abdominal muscles on each side.

Key anatomical points:

• Muscle belly tissue does not hold sutures well (sutures pull through it)
• The fascia of the linea alba is the tissue with suture-holding strength
• Suture bites must capture 4 to 10 mm of fascia to achieve adequate closure
• Bites placed too far from the incision edge are weaker than those close to it

This is why the incision for abdominal surgery is deliberately made on the linea alba: it provides the holding layer needed for secure closure.

For how muscle closure fits within the full layered technique, see muscle layer within the full layered technique.

Suture materials for muscle layer closure

PDS is considered the preferred choice for muscle and fascial closure in most small animal surgeries. Its extended strength retention supports the healing tissue through the critical weeks when the abdominal wall is rebuilding tensile strength.

For the full material selection decision including how tissue type affects the choice, see suture material selection for muscle closure.

Suture patterns used for muscle closure

Simple continuous pattern

The most common choice for linea alba closure. A single running suture distributes tension evenly along the entire closure length.

Advantages:

• Faster than interrupted
• Even tension distribution
• Uses less suture material

Disadvantage:

• If the suture breaks, the entire closure is at risk

WCVM (University of Saskatchewan): "The simple interrupted and simple continuous patterns are both appropriate to close the abdominal wall in small animals. Simple continuous is preferred by most surgeons as it is as strong as the interrupted but is faster and places less foreign material."

Simple interrupted pattern

Individual sutures placed separately. If one fails, the others remain intact.

Best used when:

• Tissue quality is poor and continuous pattern failure risk is elevated
• Activity restriction compliance after surgery is uncertain (per WCVM guidance, 2-0 suture may be used in these cases)
• The wound is under variable tension along its length

Near-far-far-near (Tension-relieving)

Used when wound edges are difficult to appose without excessive tension. Not a substitute for proper dead space elimination.

For technique details on closing the fascial layer adjacent to muscle, see fascial layers closed alongside muscle layers.

Suture size selection for muscle closure

Size varies by patient weight. Veterian Key general guidelines for abdominal wall closure:

These are guidelines. Tissue condition, wound tension, and surgeon judgment all influence the final choice.

For how tissue type determines the technique across all layers, see how tissue type determines muscle closure technique.

Complications from inadequate muscle closure

Incisional hernia: the most serious outcome. Abdominal organs push through the fascial gap. Visible as a soft bulge at the incision site weeks to months after surgery. Requires surgical repair.

Wound dehiscence: the incision reopens. Can occur superficially (skin only) or at depth. Deep dehiscence is a surgical emergency.

Seroma and hematoma: inadequate closure leaves dead space where fluid accumulates.

Infection: dead space and insufficient tissue apposition create conditions favorable to bacterial growth.

For how muscle closure decisions affect absorbable suture choice, see absorbable sutures used in muscle closure.

What owners can do to protect muscle closure

The sutures your vet placed will hold the muscle layer together, but only if the dog is rested appropriately.

Critical owner actions:

• No jumping or running for the full restriction period (usually 10 to 14 days minimum, longer for orthopedic procedures)
• No stairs unsupervised for the first week post-surgery
• E-collar on at all times to prevent licking at the external wound
• Contact your vet immediately if a soft bulge appears near the incision, which may indicate early hernia

Frequently asked questions

My dog seems to be healing well. Can she start normal activity sooner?

Surface healing does not reflect deep healing. The linea alba and muscle fascia take 4 to 6 weeks to regain functional strength. The wound may look completely healed externally while the internal closure is still remodeling. Follow your vet's activity restriction timeline, not how the incision looks.

Is the linea alba always closed the same way in all abdominal surgeries?

The general approach is consistent, but suture size, bite spacing, and pattern may be adapted for the specific procedure. Emergency abdominal surgeries (where contamination is a factor) may use a more conservative protocol. Elective procedures like spay surgery follow a well-established routine.

What does a hernia look like after surgery?

An incisional hernia typically appears as a soft, reducible bulge near the incision line. It may appear weeks after surgery as swelling resolves and the gap becomes visible. Some hernias are only detectable on palpation. If you notice any new lumps near a healing incision, contact your vet promptly.

Muscle layer closure is the step that holds everything else together, literally. The skin closure an owner can see represents the final 10% of the closure process. The linea alba and fascial repair underneath are what determine whether the patient heals without complication or returns for a second surgery.

Resources

• Veterian Key. Surgery of the Abdominal Cavity. veteriankey.com
• WCVM University of Saskatchewan. Lab 6 Part 4: Incision Closure. wcvm.usask.ca
• Veterian Key. Suturing Techniques and Common Surgical Procedures. veteriankey.com
• WSAVA 2016 (VIN). Suture Materials. vin.com

Intradermal closure is the default skin closure method for most feline elective procedures at many practices. That is not coincidence it is the result of feline-specific factors that make buried sutures significantly preferable to external sutures in cats.

Cats lick aggressively. Their skin is thin and marks easily at suture entry points. And they tolerate E-collars with varying degrees of resentment. Intradermal closure addresses all three issues simultaneously.

Quick answer: Intradermal (subcuticular) closure in cats places a continuous horizontal suture within the dermis, below the epidermis. No external material is visible or accessible to lick. The material of choice is 4-0 Monocryl (poliglecaprone 25) because of its smooth surface, minimal tissue reaction, and appropriate absorption timeline (90 to 119 days well after skin healing is complete). No removal visit is required. Published data (PMC2885123) confirms absorbable sutures are equivalent to non-absorbable for intradermal closure in cats.

Key takeaways

• No external material is visible or accessible the suture runs entirely within the dermis.
• 4-0 Monocryl is the preferred material: minimal tissue reaction, smooth monofilament, appropriate absorption.
• No removal visit required with absorbable intradermal closure reduces stress for cat and owner.
• Knots must be buried in subcutaneous tissue poorly buried knots cause licking, irritation, and increased infection rates.
• Published evidence confirms absorbable and non-absorbable sutures are equivalent for intradermal closure in cats (PMC2885123).
• E-collar still required for 10 to 14 days the incision surface can be disrupted by licking even without external sutures.

Why intradermal closure is preferred in cats

Cats lick wounds aggressively

Cats will access abdominal spay incisions with their hind legs even with a properly fitted standard E-collar. Their grooming behavior is persistent, systematic, and effective at removing sutures. External sutures which protrude above the skin surface are significantly more accessible to licking than buried intradermal sutures.

WCVM (University of Saskatchewan): "Knots are buried at the beginning and the end of the pattern. Poorly buried knots are frequently associated with excess licking, irritation and increased infection rates."

Feline skin is thin and marks easily

Suture entry points in feline skin create more pronounced tracks and marks than in most dog breeds. External suture patterns whether interrupted or cruciate leave visible marks at removal that become permanent scars. Intradermal closure creates no percutaneous tracks.

E-collar compliance challenge

Many cats resist standard E-collars. Owners may remove collars prematurely. Intradermal closure reduces the critical window during which self-trauma can remove sutures there are no external sutures to remove. Licking can still disrupt epidermal healing, but the damage threshold is higher.

The technique

Preparation

The dermis must be well exposed before starting. After subcutaneous closure, the wound is assessed at the dermal level not just the skin surface.

Needle entry at the commissure (start)

1. The first bite enters the subcutaneous tissue at one end of the wound, 3 to 4 mm from the commissure (wound end)
2. A square knot is tied in the subcutaneous tissue (start knot this buries the knot below the dermis)
3. The suture is redirected toward the wound

PMC9960444 (Comparison of Absorbable and Nonabsorbable Sutures for Intradermal Closure in Dogs): "The initial knot of the suture material was buried in the subcutaneous tissue at a distance of 4 mm from the commissure of the wound with a square knot (5 throws), and then the suture material was directed towards the start of the incision in the middle of the dermis."

Running dermal bites

1. The needle takes horizontal bites through the dermis, alternating sides left dermis, then right dermis, advancing 3 to 4 mm with each pass
2. Each bite enters and exits within the dermis, well below the epidermis the suture never crosses the skin surface
3. Tension is maintained so each bite draws the wound edges into apposition as the suture is placed

End knot

1. At the wound end, an Aberdeen knot (or standard buried square knot) terminates the suture in the subcutaneous tissue again buried below the dermis
2. The wound surface should show no suture material only a thin, clean incision line

WCVM: "For the intradermal, an absorbable suture material is indicated. A monofilament is typically preferred because of decreased tissue drag. The skin heals rapidly so a rapidly absorbable suture, like poliglecaprone 25, can be used."

Material selection

Preferred: 4-0 Monocryl (poliglecaprone 25)

• Rapidly absorbable monofilament
• Loses 50% of tensile strength by 7 to 14 days, 100% by 21 days well matched to feline skin healing timeline
• Smooth surface: minimal tissue drag during placement, minimal inflammatory reaction
• Fully absorbed by 90 to 119 days

Published evidence on material choice in cats

PMC2885123 (Comparison of Absorbable and Nonabsorbable Sutures for Intradermal Skin Closure in Cats, 6 cats): Compared Monosyn (absorbable) to polypropylene (non-absorbable). Conclusion: both produced equivalent healing outcomes. Absorbable was preferred because it eliminates the need for later suture removal.

This publication is a feline-specific study confirming what the canine literature (PMC9960444) similarly demonstrated: both material types work; absorbable eliminates the removal visit and is therefore the preferred choice.

For how intradermal material selection compares in dogs, see intradermal material in dogs vs cats.

Where intradermal closure is used in cats

• Spay (OVH): the most common application; routine skin layer closure for the ventral midline incision
• Lateral flank spay: some practitioners use an intradermal closure for the flank approach spay as well
• Mass removal: any small-to-medium sized mass removal where primary closure is achievable without tension
• Biopsy sites
• Traumatic lacerations: only if fresh, clean, and low-tension

For how intradermal closure fits within the full cat spay closure protocol, see intradermal closure in the cat spay protocol. For the full skin closure method comparison including how intradermal ranks, see skin closure methods that include intradermal. For cosmetic closure outcomes that intradermal achieves in cats, see cosmetic outcomes of intradermal closure in cats.

What owners should expect

Immediately after surgery

• No visible sutures or knots
• A thin, clean incision line may have a tiny sealed wound at each end where the buried knots were placed
• Mild swelling and redness at the incision for 2 to 3 days: normal

Under the skin

A faint, firm ridge may be palpable along the incision line for the first 3 to 4 weeks. This is the suture material within the dermis it is normal and will resolve as the suture absorbs.

E-collar

Still required. The E-collar is not for removing sutures there are none to remove. It prevents licking that would disrupt epidermal healing before the wound surface has adequate strength.

No removal visit (for wound)

There is no suture removal appointment. A post-operative recheck is still recommended at 10 to 14 days to assess healing, but the visit does not involve suture removal.

For how suture removal timing applies when external sutures are used instead, see suture removal timing context in cats.

Complications specific to intradermal closure in cats

Suture reaction: if the suture material provokes a localized inflammatory response, a small firm nodule may develop along the incision in the first few weeks. This is usually self-resolving but should be assessed if it is growing or the cat is uncomfortable.

Knot protrusion: if the start or end knot was not adequately buried, the suture ends may emerge through the wound commissure. This creates a licking target contact your vet if you notice a small loop of suture appearing at the wound end.

Wound gaping: if the intradermal suture does not achieve adequate tension throughout the closure, a small gap may appear at the wound surface. This is uncommon with correctly placed technique but may require one or two interrupted sutures at the gap site.

Frequently asked questions

My cat had her spay done and has no visible sutures. The vet said she has "dissolvable" sutures inside. How long do they last?

The intradermal suture is 4-0 Monocryl, which loses its strength by 21 days (well after skin healing is complete) and fully absorbs by 90 to 119 days. You will not feel it dissolve the process is gradual and internal. By around 3 months post-surgery, there is no foreign material remaining at the incision site.

Does intradermal closure hurt more when healing?

No. The absence of external sutures actually reduces discomfort compared to external interrupted sutures, which can cause local irritation and pull as the skin swells slightly during healing. The buried intradermal pattern is well tolerated.

My cat's incision has a small bump at one end. Is that the knot?

Possibly the start and end knots are placed in the subcutaneous tissue just beyond the wound ends. A small, firm bump in those locations is the buried knot dissolving over the first few weeks. If the bump is growing, soft and fluid-filled, or the cat shows signs of discomfort around it, contact your vet.

Intradermal closure in cats is the right technique for the right patient: a species that will self-trauma external sutures, whose skin marks easily, and whose owners struggle with E-collar compliance. By burying everything the cat might otherwise access, intradermal closure removes the most predictable source of post-operative closure complications in feline surgery.

Resources

• WCVM University of Saskatchewan. Lab 6 Part 4: Incision Closure. wcvm.usask.ca
• PMC2885123. Comparison of Absorbable and Nonabsorbable Sutures for Intradermal Skin Closure in Cats. pmc.ncbi.nlm.nih.gov
• PMC9960444. Comparison of Absorbable and Nonabsorbable Sutures for Intradermal Skin Closure in Dogs. ncbi.nlm.nih.gov