The International Commission on Radiological Protection (ICRP) currently recommends a maximum of 50 rem (500 millisieverts, or mSv) of occupational hand-radiation exposure annually. A fascinating study using a surgeon manikin, mini and standard fluoroscopic c-arms, and a Sawbones model of distal radial fracture fixation showed that hand-radiation exposure averaged 31 µSv per minute. That finding suggests that hand surgeons would not approach the ICRP-recommended hand-exposure limit unless they performed close to 2,000 hand procedures involving fluoroscopy each year. However, authors Hoffler et al. are quick to add that “the effect of consistent exposure that does not exceed the annual limit, but continues for a multiple-decade career, is unknown.”
It comes as little surprise that treating a distal radial fracture can be a high-exposure event. To quantify the situation more precisely, Hoffler et al. fit a surgeon manikin with radiation-attenuating glasses, thyroid shield/apron, and gloves, and measured radiation exposure with dosimeters placed on the manikin in both exposed and shielded positions. They exposed the Sawbones model and the manikin, which was in a standard seated position for hand surgery, to radiation from three mini and three standard fluoroscopes for fifteen minutes continuously. The authors explained their rationale for fifteen minutes of continuous exposure as follows: “The mean fluoroscopy time for volar radial plating at our institution is sixty seconds…It is common for hand surgeons to use a fluoroscope fifteen times a month…If exposures average sixty seconds each, the hand surgeon could be routinely exposed to fifteen minutes of fluoroscopy monthly.”
The authors found that hand exposure was 13 times higher than exposures at the thyroid, groin, or chest. The eyes, the second-most exposed site, received an average of 4 µSv per minute. Radiation-attenuating gloves reduced hand exposure by a mean of 69%, and radiation-attenuating glasses decreased eye exposure by a mean of 65%. There were no significant differences in hand exposure between the mini and standard fluoroscopes.
OrthoBuzz encourages orthopaedic surgeons to consider these findings in light of the current proliferation of fluoroscopes outside the OR, especially in office settings. For their part, the authors encourage surgeons to minimize their own and their patients’ radiation exposure “by understanding the basic physics of x-ray radiation and maximizing all of the safety technologies that their specific fluoroscopy units offer,” including the use of personal protective equipment.