Its a wick. When you get a deep infection they drain it, then pack the wound with as much of that as they can push in. They want wound to heal from the inside to outside so the infection doesn't get sealed in. They repack it every other day ir so. Wick gets smaller and smaller. The packing hurts like a mother ****er.
iodiform, I've packed many wounds with it, l had a length almost that long in one guy's face in Iraq, he had to come in and see me to get it re-packed every day for a week.
I had that done to my back and neck when i had mrsa about 5 years ago, back hurt worse than the neck, but they both sucked. Now on deployments i purell the **** out of everything. That **** is everywhere.