Sutures, commonly known as stitches, are medical materials used to hold body tissues together after an injury or surgical procedure. They allow wound edges to remain closely approximated while the underlying tissue repairs itself. A “spitting stitch” occurs when a buried suture material, intended to dissolve inside the body, begins to emerge through the skin surface. This phenomenon is a common post-operative occurrence that is typically the body’s natural attempt to expel a foreign object.
Why the Body Rejects Absorbable Sutures
The primary cause of a spitting stitch is the body’s natural response to the suture material. This reaction is classified as a foreign body reaction, a localized inflammatory process that occurs when the immune system encounters a substance it cannot easily break down or integrate. Absorbable sutures, such as those made from synthetic polymers like poliglecaprone (Monocryl) or polyglactin 910 (Vicryl), are designed to be broken down by hydrolysis.
When a suture is placed too close to the skin surface, or if the body’s localized inflammatory response is particularly strong, the material may be encapsulated and pushed outward. This extrusion process is the body’s attempt to eliminate the foreign object rather than wait for the full absorption process to complete. Spitting stitches typically occur weeks to months after the original surgery, often beginning around four to six weeks post-operation. The timing depends on the specific material used, as some long-lasting sutures can take several months to fully dissolve.
How to Visually Identify a Spitting Stitch
A spitting stitch is often first noticed as a small, localized abnormality along the incision line that was previously healing well. The most common initial presentation is a small, pink or reddish bump that can resemble a pimple or a minor skin irritation. This bump is highly localized, meaning the redness and swelling are confined to the immediate area surrounding the emerging material.
The definitive visual sign is a tiny piece of thread or knot protruding from the center of the bump. The material may look like a piece of white, clear, or off-white thread, depending on the type of suture used. Sometimes, a small amount of clear or yellowish fluid is present, rather than the thick, foul-smelling pus associated with a serious infection. This localized extrusion is a clear indication that the body is successfully pushing the foreign material to the surface.
Spitting Stitches Versus Surgical Site Infection
Distinguishing a spitting stitch from a true surgical site infection is important for patient safety and appropriate management. A spitting stitch causes highly localized inflammation, where the redness and tenderness are limited to the immediate point of suture extrusion. The patient usually does not experience systemic symptoms like fever or general malaise.
A surgical site infection, in contrast, presents with widespread and intense symptoms. Signs of a true infection include spreading redness and warmth that extends significantly beyond the incision line, often accompanied by increasing and intense pain. The discharge from an infection is frequently copious, thick, and may have a foul odor, and the patient may develop a fever or chills. If the entire area is becoming increasingly swollen and painful, and the redness is rapidly spreading, it suggests a deeper infection that requires immediate medical attention.
Safe Steps for Managing the Exposed Suture
If a thin piece of suture material is visible, the primary goal is to manage the exposed thread without causing further trauma to the healing wound. It is generally safe to clean the area gently with mild soap and water, keeping the site dry afterward. If the exposed thread is short and easily accessible, some healthcare providers may advise trimming the material close to the skin’s surface with clean scissors.
Never forcefully pull on the suture, as this can disrupt the underlying healing tissue or pull a deeper knot out prematurely. If the thread does not come out with a very gentle tug, or if removing it causes any pain or bleeding, it should be left alone and trimmed instead. If the exposed knot is large, deeply embedded, or if the surrounding skin is showing signs of escalating irritation or pain, a healthcare provider should be contacted, as they can safely remove the material in a sterile environment.