Shielding of the Trunk During Extremity Imaging Reduces Radiation Exposure in Pediatric Patients

BACKGROUND: Although pediatric patients are particularly sensitive to the effects of ionizing radiation, there are no established protocols for shielding the trunk during extremity orthopaedic procedures. However, some suggest that shielding not be used on the patient as it may increase radiation exposure. In this study, we aimed to quantify the effect of lead shielding on the trunk at 3 critical anatomic locations during upper-extremity imaging. METHODS: A mannequin (Laerdal Medical) approximating the size of a 5-year-old was positioned supine with the upper-extremity extended over a hand table. Exposures of the forearm were performed with a fluoroscopy machine (GE Healthcare) at 110 kVp and 4.5 mA for 10 seconds. A dosimeter (Mirion Technologies) was used to assess radiation exposure at the neck/thyroid, chest/breast, and groin. Readings were assessed with the image intensifier in both the above and the below configuration, with and without a radiation shield placed in different configurations over the trunk. Each configuration was replicated 5 times. RESULTS: Without shielding, the neck/thyroid received 110.5 and 132.7 mSv, the breast/chest received 125.8 and 118.8 mSv, and the groin received 44.9 and 46.7 mSv with the receiver below and above, respectively. These values were significantly higher than those with an anterior shield (42.9 and 80.8, 37.0 and 68.8, and 12.9 and 32.3 mSv). The addition of a side lead significantly reduced radiation exposure compared with anterior shielding alone in most locations (19.4 and 95.8, 24.0 and 46.7, 0.0 and 0.0). CONCLUSION: Radiation shields placed anteriorly over a child significantly reduced radiation exposure in 3 anatomic areas. The addition of a side wrap-around shield further reduced exposure. CLINICAL RELEVANCE: Although fluoroscopy is commonly used in extremity procedures, there is no standard guideline for radiation shielding in pediatric orthopaedic procedures. This data suggests that physicians should strongly consider placing shielding to create a radiation shadow that blocks scattered radiation from the imaged extremity. While the mannequin was the size of a child, these recommendations may be translatable to adult patients as well.