Since 1980, the United States has experienced a sixfold increase in medical radiation exposure. Estimates suggest that up to 3% of all future malignant neoplasia could be caused by previous ionizing radiation exposure . Several studies, therefore, have been and are being conducted to gather information to develop education for using the best available evidence and technology, while preventing harm to patients and medical teams.
Currently, the literature contains conflicting evidence regarding some effects of ionizing radiation. One interesting idea is that daily radiation exposure in male doctors while working may increase the chances of producing female offspring. Zadeh and Briggs published one of the first related studies in 1997. They reported that male obstetricians, gynecologists, and orthopedic surgeons in the United Kingdom had a higher incidence of female offspring . In addition, an increased risk for congenital abnormalities was present, and a statistical difference existed in all the findings compared to the population . Since the obstetricians and gynecologists were not exposed to radiation, Zadeh and Briggs proposed that occupational exposure to x-ray was not associated with the findings, and the possible cause was exposure to the operating theatre environment . However, Hama et al. from Japan divided participants of his study into two groups, “lightly irradiated” and “highly irradiated” (one or more incidents of annual radiation exposure > 10 mSv). They found a significant statistical increase in the risk of radiologists from the “highly irradiated” group producing a lower proportion of male offspring . The most recent study on this topic published by Choi et al. used a sample of male invasive cardiologists. The authors found no significant difference in the proportion of male and female offspring, even when analyzing a subgroup with higher radiation exposure . In the present study, we found similar results to Choi et al. and Zadeh and Briggs. No difference was identified in the proportion of male offspring born to male orthopedic surgeons in Brazil. The proportions were similar to the Brazilian population. We also compared a group of lower radiation exposure to one of higher exposure, determined by the number of surgeries requiring fluoroscopy per week per surgeon. Again, no difference was found in offspring gender proportion.
Another controversial topic is the relationship between lead apron use and back pain in orthopedic surgeons or professionals that deal with x-rays. To our knowledge, the first study investigating this relationship was published by Moore et al. and did not prove lead apron use as a risk factor for back pain . Later, research on the prevalence of spinal disc disease among interventional cardiologists argued the existence of the “interventionalist’s disc disease”. It reported significant differences between the incidence of skeletal complaints among interventional cardiologists compared to orthopedists and rheumatologists . Their study showed a greater incidence of cervical, rather than lumbar, problems. It was also noted that interventional cardiologists use aprons for longer periods, which increases the impact on the axial skeleton . However, our study produced results similar to Moore. No significant relationship occurred between back pain frequency and apron use among orthopedic surgeons in Brazil, but the descriptive analysis showed that most of our participants complained of back pain during prolonged surgeries. Therefore, we think that more hours of apron use might be necessary to cause harmful effects and related back pain, similar to the study of interventional cardiologists. Even without apron use, prolonged procedures might be a cause of back pain, although we have yet to see a study comparing both situations.
Our study also assessed how orthopedic surgeons in Brazil protect themselves from occupational ionizing radiation and whether they know the theory behind prevention from harmful x-rays. Unfortunately, the results showed a lack of radiation protection equipment use and lack of knowledge about basic radiation prevention. In our sample, 65.9% only used the apron as protection equipment despite the well-known fact that radiation is the main risk factor for thyroid cancer. Only 32.1% used at least the apron and thyroid shield, and 5.8% used the apron, thyroid shield, and radiation protection glasses. The dosimeter was not used by the majority, 52.7%, and only 22.1% always used it. A study about fluoroscopic radiation exposure highlighted that surgeon eyes and hands receive more radiation than other body parts, and therefore surgeons should routinely use eye and hand protection in addition to the apron and thyroid shield . It is noteworthy that a study published by Muir et al. showed that some aprons were labeled as having higher protection than they in fact presented when tested.
Regarding the questions on radiation prevention knowledge, most of the orthopedic surgeons answered poorly. Only 2.7% reached the acceptable annual maximum permissible radiation dose. Just 10.5% knew the period of greater risk to the fetus when exposed to x-rays, and 5.8% reached the maximum permissible radiation dose during pregnancy. About one quarter, 25.2%, knew that 3 meters or more from the radiation-emitting tube is considered the safe distance, and 44.2% knew the safest positioning of the radiation-emitting tube. Only 25.2% knew that smaller tubes generally emit greater radiation at the entrance dose to magnify the image. Just over half, 55.4%, knew that the surgery team receives more scattered radiation in surgical procedures performed on obese patients. Finally, the question if the hand, eyes, and thyroid are the most exposed and at greater risk of radiation-related lesions was correctly answered by only 58.5% of participants.
No significant differences in knowledge were found when comparing all orthopedic surgery specialties. All specialties performed similarly. It seems that the poor performance on the survey is not limited to Brazil. An original study in 2013 showed that orthopedic surgeons from Canada lacked knowledge about the risk of eye cataracts when exposed to radiation, and 75% were unaware of radiation dose limits . A survey analysis from Turkey demonstrated inadequate knowledge about the uses and risks of fluoroscopy and radiation prevention . Another article from Latin America showed that 75.7% of their sample rarely or never used a dosimeter badge, and only 20.2% used lead glasses in their practice. The article also highlighted significant differences and many knowledge deficiencies among countries .
An interventional study was performed to analyze the effect of surgeon education about radiation protection . The educational intervention was applied to surgeons performing complex endovascular procedures. A strong relationship (p < 0.001) between the intervention and decrease in radiation dose was found, excluding cases of fenestrated endovascular aneurysm repair which continued to present high radiation exposure . Additionally, some articles summarize the main important aspects of how to decrease unnecessary radiation exposure, by explaining radiation effects, dose, and protection equipment. These articles highlight that minimally invasive surgery increases radiation exposure, especially in cases of spinal surgery [19, 20]. The concepts of ALARA (as low as reasonably achievable) and DEBT (distance, exposure, barriers, and time) are highlighted as pillars of practical guidelines [2-6, 21].
As a main limitation, our study design and sample characteristics preclude concluding that orthopaedic surgeons worldwide present the same knowledge regarding radiation exposure and safety procedures to avoid harmful effects. Another limitation is the lack of uniformity among subspecialties. We had 134 trauma surgeons versus 6 pediatric surgeons, 15 foot and ankle surgeons, and 17 hand surgeons, potentially limiting comparison among specialists in terms of knowledge and other variables analyzed in the study. Nevertheless, by focusing on basic education for medical residents before specialization, we feel our data demonstrates quite clearly that orthopedic practitioners present a low level of knowledge regarding the harmful effects of radiation exposure.