What are "spitting sutures"?
Sutures, or stitches, are threads used to hold the edges of a wound together, allowing the skin and deeper tissues to heal. While some stitches are removed by a healthcare provider, others, known as dissolvable or absorbable sutures, are designed to break down and be absorbed by the body over time. A "spitting suture" is a common and often harmless phenomenon where the body expels a piece of suture material to the surface of the skin. This can occur with both dissolvable and non-dissolvable sutures, but is a key part of the process for absorbable materials.
The mechanism of foreign body rejection
The body's immune system is programmed to identify and eliminate foreign materials. While sutures are medically inert, they are still foreign objects. As the wound heals around the sutures, the body's natural inflammatory response can sometimes treat the suture material as a foreign invader. Instead of the material dissolving internally as intended, the body walls it off and pushes it out through the skin. This can happen days, weeks, or even months after the initial procedure.
Distinguishing normal dissolution from extrusion
For dissolvable stitches, it is completely normal for them to fall off or be absorbed as they break down. This is a slow and gradual process. Extrusion, or spitting, is a more active form of rejection where the body forces a piece of the suture material out. The key difference lies in the visible threads: during normal dissolution, you may notice tiny pieces of the thread fall off, whereas with extrusion, a thread may actively poke through or emerge from the skin with a red bump.
Signs that stitches are pushing themselves out
Recognizing the signs of a spitting suture can help you manage your wound care correctly. Common indications include:
- Visible thread: A small piece of suture, which may be white or clear, pokes out from the incision line.
- Red bump: A small, pimple-like red bump or inflamed spot appears along the incision.
- Irritation and discharge: There may be minor redness, swelling, or a small amount of discharge (which may be white blood cells, not necessarily pus) around the protruding stitch.
- Sharp sensation: You may feel a sharp or poking sensation as the hard suture material moves towards the surface of the skin.
Why does suture extrusion happen?
Several factors can contribute to suture extrusion:
- Immune response: The body's normal immune reaction to foreign material is the most common cause.
- Excessive tension: If a suture is placed under too much tension, it can create a pulling force that pushes it out over time.
- Incision location: Areas of the body with more movement, such as joints, can be more prone to extrusion due to constant stretching and pressure.
- Suture material: Some materials, particularly older, more reactive types like chromic gut, are more likely to cause a reaction than newer synthetic materials.
Do all types of stitches push themselves out?
No, not all stitches behave the same way. The likelihood and manner in which they exit the body depends on whether they are designed to be absorbed or are permanent. It is crucial to know which type of sutures you have.
| Feature | Dissolvable (Absorbable) Sutures | Non-Dissolvable (Permanent) Sutures |
|---|---|---|
| Material | Made from natural or synthetic materials that are broken down by the body's enzymes or hydrolysis. | Made from materials like nylon or silk that are not absorbed by the body. |
| Behavior | Gradually break down and are absorbed over weeks or months. May be actively expelled by the body in the case of extrusion. | Remain intact and require manual removal by a healthcare professional. Should not come out on their own. |
| Expulsion | Normal dissolution occurs over time. Extrusion involves the body actively pushing out material that hasn't fully broken down. | Not designed for expulsion. If they come out, it may indicate that the knot has come undone or the wound is under excessive stress. |
| Management | Often fall off on their own. Protruding pieces may be gently clipped or removed by a professional. | Must be professionally removed. If they come loose, it requires immediate medical attention. |
How to care for a spitting stitch
If you notice a spitting suture, follow these steps to ensure proper healing and prevent complications:
- Do not panic: Suture extrusion is a common and typically benign event. Stay calm and assess the situation.
- Assess the wound: Check that the wound edges are still held together and that there is no excessive bleeding or drainage.
- Clean the area gently: Wash your hands and gently clean the area around the stitch with mild soap and water. Avoid harsh rubbing.
- Try gentle removal: If the stitch is visibly poking out and feels loose, you may attempt to remove it with sterile tweezers. If there is any resistance, do not pull.
- Trim the thread: If the thread does not come out easily, you can use a sterile nail clipper or scissors to trim the excess thread close to the skin's surface. This reduces irritation.
- Apply ointment: A thin layer of antibiotic ointment can be applied to keep the area clean, followed by a bandage.
- Monitor for infection: Continue to watch for any signs of infection, such as increased redness, swelling, or pain.
When to contact a healthcare professional
While spitting sutures are often harmless, certain signs indicate a more serious problem. Contact your doctor immediately if you experience:
- Signs of infection: Worsening redness, warmth, swelling, pus, a bad odor, or fever.
- Wound opening: The incision line separates or pulls apart significantly.
- Excessive bleeding: Continuous or heavy bleeding from the wound.
- Significant discomfort: Pain that increases rather than improves over time.
- Non-dissolvable sutures: If a permanent suture comes loose on its own.
Conclusion
In summary, the question of whether do stitches push themselves out has a clear answer: yes, they can. This natural biological process, known as suture extrusion or "spitting a stitch," is the body's way of expelling foreign material. While it can be alarming to witness, it is generally a normal part of the healing process, especially for dissolvable sutures. The key is to know what to look for, perform proper wound care, and understand when the situation warrants a call to your healthcare provider to rule out infection or other complications. For most patients, it is a minor setback on the road to a full recovery. A guide to Incision & Surgical Wound Care, Cleveland Clinic offers additional tips on managing surgical wounds.
