How Mattress Suture Technique Distributes Tension Along a Skin Closure

Mattress suture technique is a family of skin closure patterns in which the suture passes through both wound edges more than once before it is tied. The reason to use it is tension. A clinical article by a board certified veterinary surgeon at MSPCA-Angell states that closure of a wound under excessive tension is the most common cause of wound dehiscence, and the mattress patterns are one of the ways a surgeon shares that load.

This article explains how the horizontal and vertical patterns differ, what each does to the wound edge, and where each carries a risk. Most of the detailed figures come from a human wound care article, and the article flags where that matters. It also sets out which Gexfix materials suit a skin closure and where mattress sutures are the wrong tool.

What Is Mattress Suture Technique?

Mattress suture technique covers two main patterns, the horizontal mattress suture and the vertical mattress suture. The Large Animal Surgery notes on the University of Minnesota open library state that both patterns are everting and force the cut edges outward. Eversion is the shared feature, and the two patterns differ in what else they do. The wider comparison of skin closure patterns is covered in the guide to the best sutures for skin closure after surgery.

Horizontal Mattress Suture

The American Family Physician article on the mattress sutures describes the horizontal mattress suture as an everting technique that spreads tension along a wound edge. It lists pulling wound edges together over a distance, anchoring sutures, holding flaps and holding fragile skin among its uses, and it notes that the pattern is an effective haemostatic suture on vascular tissue such as the scalp.

The same article places the first pass 4 to 8 mm from the wound edge, and later passes advance along the wound edge. It also states the cost. If the suture is tied tightly, the loops can strangulate the skin they enclose, and bolsters of plastic tubing, cardboard or gauze may be placed under the loops.

Vertical Mattress Suture

The AAFP article gives the main indication for a vertical mattress suture as everting the skin edges. The far-far passes lie 4 to 8 mm from the wound edge and deep, and the near-near passes lie within 1 to 2 mm of the edge. The article says the suture should be tied snugly but gently, because over-tightening increases eversion and tension and can cause tearing or necrosis, with necrosis described beneath the external loops. It adds that surface loops can leave cross-hatched marks that limit use on cosmetically sensitive areas.

The AAFP article is written for human wound care. Its distances are not veterinary specifications, and canine and feline skin differs in thickness and mobility. They show how the patterns are built, not how far a given bite should sit in a given dog.

Why Tension Decides Wound Closure

The MSPCA-Angell article, written by Michael Pavletic, DVM, DACVS-SA, gives a mechanism for why the bite position matters. Collagenase activity remains high within 5 mm of the skin incision, which means the tissue within about 5 mm of the incision is where the wound is weakest. In the AAFP description the near-near pass of a vertical mattress suture lies within 1 to 2 mm of the edge, which is inside that zone. That is one reason the human figures cannot be applied to a dog or cat without judgement.

The same article lists the surgical options for reducing tension at closure. They are careful undermining, release or relaxing incisions, load cycling with skin hooks, tacking sutures including walking sutures, skin flaps and skin stretchers. The article does not name mattress sutures, so they are one option among several, and the guide to the causes of surgical wound dehiscence in dogs explains how closure tension acts on every bite of the suture.

Comparing Horizontal and Vertical Mattress Patterns

The table sets the two patterns side by side using the figures in the AAFP article. The figures describe human wound care and are shown to explain the difference between the patterns, not to set a veterinary standard.

The difference in purpose is the useful part. On the AAFP descriptions, the horizontal pattern is the tension tool and the vertical pattern is the eversion tool, so a closure under tension calls for the first and a closure whose priority is eversion calls for the second.

The Minnesota notes show a related use in a large animal setting. A mattress suture is placed, a simple continuous pattern is placed across the skin margins, and the mattress suture can be removed after the skin stretches, which the notes give as 3 to 4 days. The resources on that page focus on horses, so this is a large animal example and is not a timing for dogs or cats, but it shows that a mattress suture can act as a temporary load sharing device for a second closure.

Choosing Suture Material for Mattress Closure

The AAFP article states that all of the techniques it describes use nonabsorbable suture material, and it notes that large-diameter absorbable sutures of 2-0 or 3-0 cause more skin injury than 5-0 or 6-0 material. Those sizes are from human practice. The Gexfix Product Reference positions ASSUNYL® polyamide, a non-absorbable monofilament, for skin closures and external use, with low tissue reactivity, and it notes that the suture requires removal if it is not subcuticular. A mattress suture is not subcuticular, so removal is part of the plan.

The Product Reference positions the absorbable materials for soft tissue closures, and the table sets them beside polyamide. The guide to polyamide nylon suture covers the material in more detail.

The Product Reference does not name mattress sutures or any skin closure pattern. The final row therefore combines the AAFP statement about nonabsorbable material with the Product Reference positioning, and it is a reasoned match, not a manufacturer claim.

When Mattress Sutures Are NOT the Appropriate Choice

When Another Tension Technique Fits Better

The MSPCA-Angell list shows that undermining, relaxing incisions, walking sutures and flaps all reduce tension without placing loops of suture across the skin. A wound that is too tight to close with a mattress pattern may need one of those techniques first. The guide to subcuticular suture technique covers the buried alternative for the final layer.

Cosmetically Sensitive Areas

The AAFP article states that the surface loops of a vertical mattress suture can leave cross-hatched marks, which is why it limits their use on areas such as the face.

Fragile or Poorly Perfused Skin

The same article lists fragile skin as an indication for the horizontal pattern, and it also warns that tight loops can strangulate the skin. Both statements apply together, so the pattern depends on gentle tying.

Choosing a Mattress Suture Technique for a Skin Closure

The choice follows the problem. On the sources reviewed, the horizontal mattress suture fits a closure under tension and the vertical mattress suture fits edges that need eversion, and either must be tied gently. Bites within 5 mm of the edge sit in weakened tissue, and undermining, a relaxing incision or a walking suture may solve the tension more directly.

Gexfix International Corp., in partnership with Assut Europe S.P.A., supplies ASSUNYL® non-absorbable polyamide monofilament sutures for skin and external closure in veterinary practice. The complete suture range also includes ASSUFIL® PGA, PGCL MONOFIL®, ASSUFIL® PDS monofilament, ASSUCROM® Chromic Catgut and FILBLOC® Barbed Sutures. With over 30 years of manufacturing expertise and ISO 13485-certified production standards, Gexfix provides veterinary practices with the reliable skin closure sutures and full suture portfolio that consistent outcomes require.

Explore the full range at medicaldevicevet.com.

Sources

American Family Physician (Zuber T.J.), The Mattress Sutures: Vertical, Horizontal, and Corner Stitch (2002). Clinical review in a family medicine journal, written for human wound care. The author reports no conflicts of interest and no funding. Supports the descriptions of both mattress patterns, the placement distances, the risks and the nonabsorbable material statement. The article is from 2002 and is not veterinary.

MSPCA-Angell (Pavletic M.M.), Wound Dehiscence: Causes, Prevention, Management (2026). Clinical article from a veterinary hospital, written by a board certified veterinary surgeon, with no sponsor disclosure on the page. Supports the tension statement, the 5 mm collagenase zone and the list of tension reducing options.

University of Minnesota open library (Malone E.), Large Animal Surgery Supplemental Notes, Suturing: tension relieving suture patterns (undated). Teaching notes hosted by the University of Minnesota, licensed CC BY-NC 4.0, written for large animal surgery, with no publisher or date on the page. Supports the statement that both mattress patterns are everting and the equine example of a temporary mattress suture.

Absorption windows, handling notes and infection field guidance come from technical data supplied by Gexfix International Corp. and Assut Europe S.P.A. and are manufacturer information.

FAQs

Q. What is mattress suture technique and when is it used?

A. Mattress suture technique is a family of skin closure patterns in which the suture passes through both wound edges more than once before it is tied. The horizontal pattern spreads tension along a wound edge, and the vertical pattern everts the skin edges. Both are everting patterns.

Q. What is the difference between a horizontal mattress suture and a vertical mattress suture?

A. The AAFP article describes the horizontal mattress suture as spreading tension along a wound edge and the vertical mattress suture as mainly everting the edges. The vertical pattern uses far-far and near-near passes, while the horizontal pattern advances along the wound edge in passes along the wound edge. Both carry a risk of tissue damage if tied too tightly.

Q. How tightly should a mattress suture be tied?

A. Gently. The AAFP article states that the vertical mattress suture should be tied snugly but gently, and that tight horizontal loops can strangulate the skin. Over-tightening can cause tearing or necrosis.

Q. Which suture material is used for mattress skin closure?

A. The AAFP article describes nonabsorbable material for all of its techniques. The Gexfix Product Reference positions ASSUNYL® polyamide, a non-absorbable monofilament, for skin closures, and notes that it requires removal if it is not subcuticular.

Q. Why does tension matter in wound closure?

A. The MSPCA-Angell article states that closure of a wound under excessive tension is the most common cause of wound dehiscence. It also notes that collagenase activity remains high within 5 mm of the incision, which marks the zone where the wound is weakest. Mattress sutures are one of several tension reducing options.