The color of internal stitches can be yellow, purple, green, or white but it depends on the type of suture material that was used. Each type of suture material is dyed a certain color for ease of recognition. Therefore, you can often figure out what the material is from the color of it.
However, not every type of stitch is used internally because the preference skews towards absorbable suture use for the inside of the body. Non-absorbable stitches are infrequently used for internal wound closures because they’re preferred for external use.
What color are internal stitches?
Most clinicians will use absorbable stitches for suturing up wounds that are on the inside of the body. That means the vast majority of stitches that you find internally should be dissolvable ones.
Therefore, the color of internal stitches should be identical to absorbable sutures.
However, there are instances of clinicians using non-absorbable sutures internally but those situations are much more rare.
Most common colors
Since dissolvable stitches are most commonly used internally, the most common colors for the sutures would be based on their color.
| Suture Type | Color |
|---|---|
| Gut/Catgut/Chromic | Yellow-Gold |
| Polyglycolic acid (Polysyn) | Violet |
| Polyglactin 910 (Vicryl) | Violet or White |
| Polydioxanone (PDS) | Violet |
| Polytrimethylene carbonate (Maxon) | Green or White |
| Glycomer 631 (Biosyn) | Violet |
| Polyglytone 6211 (Caprosyn) | Violet or White |
| Poliglecaprone (Monocryl) | Violet or White |
The table above lists every type of stitch that can dissolve and their respective color.
In summary, the color of internal stitches are most likely going to be yellow, purple, green or white. That is because those are the colors for each respective material.
Less common colors
The less common colors for stitches that are placed internally would be the non-absorbable suture colors of black and blue. Of course, we’ve excluded the overlapping colors of white and green since some dissolvable ones come in those colors.
Below is a complete table for all of the non-dissolvable stitches and their colors:
| Suture Material | Suture Color |
|---|---|
| Silk | Black and virgin |
| Linen | White |
| Polypropylene | Blue |
| Nylon (polyamide) | Black and blue; Green |
| Polyester | Green and white |
| Polytetrafluoroethylene (PTFE/Gore-Tex®) | White |
| Polyvinylidine fluoride (PVDF) | Blue |
| Stainless steel | Steel/Metallic |
That is in case you were interested in what color they were!
Dissolvable vs Non-dissolvable for internal use
As a general rule of thumb, non-dissolvable sutures are used externally while dissolvable sutures are used internally for the body.
Reasons for stitches choices:
- Absorbable sutures elicit a stronger inflammatory response than non-absorbable ones.
- Dissolvable stitches are placed internally in order to avoid suture removal later on.
Essentially, the dissolution process for the stitches undergoes an inflammatory response. That is how your body breaks them down for absorption. Therefore, whenever it is possible it is always preferred to use non-absorbable stitches in order to decrease inflammation.
However, there are situations where removal of sutures may be difficult such as closing up an internal wound. Since your doctor cannot remove internal stitches, absorbable ones are used so that they don’t have to.
If they used non-dissolvable stitches internally, they would literally need to open you back up in order to have them removed. The risk to benefits do not warrant such an action so a dissolvable one is used instead so that they don’t have to remove them!
Exception
There is one exception to the rule which we can think of where you would get non-absorbable sutures for an internal wound. That would be if you needed an artery ligation.
An artery ligation is a surgical procedure where the artery is stitched and closed off permanently with a non-absorbable suture. This procedure can be done for any type of artery (uterine, aortic, hepatic, etc).
A classic example of when we would do this is if you had a deep laceration and an artery was lacerated. In order to ensure that you don’t bleed to death, we would typically ligate the artery with a non-dissolvable suture.
The reason is because if we place a dissolvable stitch for the ligated artery, there is a chance it may dissolve before your body can repair it. If that happens, you may bleed to death internally while you’re back at home… Having the ligation done with a non-absorbable one ensures that it won’t get dissolved once you leave the hospital!
Verdict
The color for internal stitches are most likely going to be yellow, purple, green, or white because that’s the color of dissolvable stitches. Absorbable sutures are the preferred type to use for closing internal wounds because suture removal later on would be difficult.
Placing the ones that will dissolve on their own removes the necessity of having to remove them. However, there are exceptions because there are situations where a different type of stitch is used internally.