Undermining: What it is?

Hi, I'm new to the nursing forum ... saw your post. It's been a while, so you may already have clarified your problem.

Basically, sinus tracts & tunneling is the same thing, just different terms. Undermining is a wider area of wounding that lies beneath the wound opening. Think of undermining like this: the wound is larger than the "hole" or entrance of the wound. Tunneling is like a cave, undermining is like a cavern or cavity.

Hope I've helped. Have a great day.

Undermining looks like a Michigan basement. A basement that has a ledge all the way around the open area. That is a the best description I can think of.

Underming is deep tissue (subcutaneous fat and muscle) damage around the wound margin. Tunneling is just under the skin surface and doesn't involve deep tissue, and sinus tracts are a narrow tract that are away from the wound margins and go downward into the wound. They are very different from tunnels.

Basically, undermining is like the wound is spread out underneath the skin that surrounds the visible part of the sore. So... the wound is bigger than what appears at first glance. You use a cotton tipped applicator to feel under the wound edges to see if the tip will go "underneath" the skin. If it does, the wound has undermined. Sometimes when packing a wound with wet to dry dressings, if the wet dressing touches the healthy tissue surrounding the wound, it affects the integrity of the healthy skin and can cause undermining. TUNNELING, however is like a portion of the wound that continues to travel. You actually pack tunneling with strips of gauze. Without packing the tunneling, the wound can't heal completely. The superficial part of the wound may close, but the tunneling will not. Tunnelling is often associated with abcesses.

Another thing you want to think about with undermining is what caused it. For example, if you are dealing with a sacral/coccyx pressure ulcer, shearing is most likely the cause. If the patient's head of the bed is too elevated, it may cause the patient to slip, which causes undermining. Head of the bed should not be more than 30 degrees if this is the case.

Hi I am just wondering if this wound looks like if it is tunneling or undermining...i am having trouble identifying...and to me looks like a stage 3 pressure ulcer?

Could anyone help me upload a wound photo? I am unable to find out how? It is an image on my computer so not a url.

Undermining: when the depth of the wound extends past the original opening. Sort of like a plastic water bottle.

It differs from tunneling in that tunneling is usually in one direction, whereas undermining extends past the opening in all directions.

Does that help?

I think the easiest way to describe undermining is like a lip on the inside of the wound. You can stick your finger in the wound and bend it and you feel a space. To determine how much undermining is there you run your finger or cotton tipped applicator around the lip and see how far it goes. An example of this measurement is 4x3x2 with 2cm of undermining from 2 O'clock to 4 O'clock.

Tunneling...in the wound bed or wound edges you'll see 2 distinct holes that you are able to pass a curette thru.

Sinus tract: A hole you see in the wound bed or wound edges that has no end and that you cannot see the end of.

Hope this helps.