Sponges and Positioning Aids

When a technologist needs to take an image, positioning sponges are used for generally two purposes:
First is comfort and support for a patient while imaging a specific body part. Imagine if a patient was in a car accident and broke their hand. You need to take an image of the damaged hand. However, the patient’s arm is badly scrapped or cut and they are extremely sore or bleeding. In order to position the patient properly, safely and comfortably, you may use a positioning sponge to prop up their arm. Since you are imaging only the hand, this sponge is not in the field of view. Because of this, it does not matter if this sponge is radiolucent or if it will show in an image. The sponge  is protected from the bodily fluids and can be wiped clean after use.
The other purpose is positioning of the actual body part in the image. Let’s say you need to image the hand of the patient in the car accident. However, the hand is so badly damaged that you cannot spread the fingers apart properly to get the angles needed. You may use a sponge to rest the patients hand on during the procedure. The angles or “steps” of a hand sponge will help spread the fingers and position them properly for the image. Since this sponge is in the field of view, it is extremely important that the sponge be radiolucent and will not show an artifact.