Occupational radiation exposure risk in orthopaedics
1. Occupational exposure limits
Occupational dose limits for radiation exposure are set by the International Commission on Radiation Protection.
Current recommended overall limits are:
- 20mSv/year
- or 100mSv in 5 years with no 1 year > 50mSv
These are based on average radiation exposure over a working life of 47 years, with a resultant excess cancer risk of less than 1 in 1,000. Separate limits are described for specific body tissues, such as thyroid and eyes [1].
Most orthopaedic surgeons have a dose exposure less than 2mSv/year [2,3]. This is lower than in specialities using extensive live fluoroscopy, such as interventional cardiology, interventional radiology and vascular surgery.
2. Health risks related to ionising radiation
Ionising radiation is defined by the International Agency for Research on Cancer (IARC) as a Group I human carcinogen. The carcinogenic effects of high and moderate level exposure to ionising radiation are well-known, but the impact of chronic low-level exposure is less clear. Results from the INWORKS study on nuclear workers suggest a linear increase in mortality with increasing exposure for solid cancers, lymphoma and leukaemia [4].
There is no specific longitudinal data on the risks of ionising radiation exposure in orthopaedic surgeons, either in relation to cancer risk or to other risks, such as cataract formation.
Evidence from other healthcare workers has shown increased risks of thyroid cancers, head and neck cancers and cataracts in those exposed to ionising radiation [5-7]. Self-reported surveys of US female orthopaedic surgeons have suggested an increased all-cause and breast cancer prevalence [8-10].
3. Who is most at risk of exposure in the operating theatre?
Aside from the patient, the operating surgeon receives the largest dose of radiation, due to proximity to the source and scatter radiation from the patient. For example, during an intramedullary nailing procedure, the assistant would receive 37-62% of the dose received by the primary surgeon, with the scrub nurse receiving 11-20% [11].
In multiple studies, junior surgeons have been shown to use more fluoroscopy and thus are exposed to higher radiation doses compared to experienced surgeons [12-14].
4. Reducing individual exposure
The following general measures can assist in reducing exposure to ionising radiation:
- Always consider the radiation principles of time, distance and shielding
- Ensure correct orientation of the c-arm
- Be aware of scatter when radiation is deflected from the patient or surfaces
- Step away from the beam when screening, if able to do so.
- Avoid the use of the image intensifier in the true lateral position where possible
- If a lateral view is required, consider a 70-degree view, with the beam directed away from the operating surgeon
- Consider the additional value of each image to the success of the procedure and minimise overall number of images
- Avoid live screening
- Wear appropriate, correctly fitting PPE
Specific methods to reduce radiation to the axilla and lateral chest wall
Additional measures that surgeons can take to reduce radiation exposure to the axilla and lateral chest wall include:
- Stand perpendicular to the beam so that it is not directed at the lateral chest
- Ensure screens are in an appropriate position to avoid twisting
- Position your body to ensure axilla is further from the beam
- Avoid the lateral view where possible, and keep arms down when screening in this position
5. What about pregnancy?
Pregnant surgeons should contact their local Radiation Protection Supervisor to discuss exposure and additional protective measures during pregnancy.
More extensive information is given here.
References
[1] AO. Characteristics of X-rays [Internet]. [cited 2023 Feb 4]. Available from: https://images.aofoundation.org/CIP/asset/download/Gallery/13464
[2] Raza M, Geleit R, Houston J, Williams R, Trompeter A. Radiation in orthopaedics (RIO) study: a national survey of UK orthopaedic surgeons. BJR. 2021 Sep 1;94(1125):20210736.
[3] Radiation protection of medical staff in orthopedic surgery | IAEA [Internet]. [cited 2022 Nov 9]. Available from: https://www.iaea.org/resources/rpop/health-professionals/other-specialities-and-imaging-modalities/orthopedic-surgery/staff#5
[4] Laurier D, Richardson DB, Cardis E, Daniels RD, Gillies M, O'Hagan J, et al. The International Nuclear Workers Study (Inworks): A Collaborative Epidemiological Study to Improve Knowledge About Health Effects of Protracted Low-Dose Exposure. Radiat. Prot. Dosim. 2017. Apr, 173, https://doi.org/10.1093/rpd/ncw314
[5] Sigurdson AJ, Doody MM, Rao RS, Freedman DM, Alexander BH, Hauptmann M, et al. Cancer incidence in the US radiologic technologists health study, 1983-1998. Cancer. 2003 Jun 15;97(12):3080–9.
[6] Roguin A, Goldstein J, Bar O, Goldstein JA. Brain and neck tumors among physicians performing interventional procedures. Am J Cardiol. 2013 May 1;111(9):1368–72.
[7] Ramoutar DN, Thakur Y, Batta V, Chung V, Liu D, Guy P. Orthopaedic Surgeon Brain Radiation During Fluoroscopy: A Cadaver Model. J Bone Joint Surg Am. 2020 Nov 18;102(22):e125.
[8] Chou LB, Johnson B, Shapiro LM, Pun S, Cannada LK, Chen AF, et al. Increased Prevalence of Breast and All-cause Cancer in Female Orthopaedic Surgeons. JAAOS Glob Res Rev [Internet]. 2022 May [cited 2022 Oct 31];6(5). Available from: https://journals.lww.com/10.5435/JAAOSGlobal-D-22-00031
[9] Chou LB, Chandran S, Harris AHS, Tung J, Butler LM. Increased Breast Cancer Prevalence Among Female Orthopedic Surgeons. Journal of Women’s Health. 2012 Jun;21(6):683–9.
[10] Chou LB, Lerner LB, Harris AHS, Brandon AJ, Girod S, Butler LM. Cancer Prevalence among a Cross-sectional Survey of Female Orthopedic, Urology, and Plastic Surgeons in the United States. Women’s Health Issues. 2015 Sep;25(5):476–81.
[11] Patra SK, Shetty AP, Jayaramaraju D, Rajasekaran S. Radiation Exposure to the Surgeon, Surgical Assistant, and Scrub Nurse During Closed Intramedullary Nailing of Long Bones-Does It Vary Depending on the Experience of the Surgeon? J Orthop Trauma. 2019 Feb;33(2):e52–7.
[12] Patel N, Mohamed A, Cooper G, McFadyen I. Ionising radiation exposure in paediatric trauma. annals. 2014 Apr;96(3):190–3.
[13] Quah C, Mehta R, Shivji F, Hassan S, Chandrasenan J, Moran C, et al. The effect of surgical experience on the amount of radiation exposure from fluoroscopy during dynamic hip screw fixation. annals. 2017 Mar;99(3):198–202.
[14] Malik AT, Rai HH, Lakdawala RH, Noordin S. Does surgeon experience influence the amount of radiation exposure during orthopedic procedures? A systematic review. Orthop Rev (Pavia) [Internet]. 2019 Mar 12 [cited 2022 Oct 31];11(1). Available from: https://www.pagepress.org/journals/index.php/or/article/view/7667
[15] Cancer Research UK. Internet. [cited 2023 Feb 8] Available from: https://www.cancerresearchuk.org/health-professional/cancer-statistics/statistics-by-cancer-type/breast-cancer.
[16] Ronckers CM, Erdmann CA, Land CE. Radiation and breast cancer: a review of current evidence. Breast Cancer Res. 2004 Feb;7(1):21.
[17] Rummel S. Tumour location within the breast: Does tumour site have prognostic ability? ecancer [Internet]. 2015 Jul 13 [cited 2022 Nov 7];9. Available from: http://www.ecancer.org/journal/9/full/552-tumour-location-within-the-breast-does-tumour-site-have-prognostic-ability.php
[18] Swergold N, Murthy V, Chamberlain RS. Males at High Risk for Breast Cancer: Who Are They and How Should We Screen Them? SS. 2014;05(07):320–31.
[19] Wang JX, Zhang LA, Li BX, Zhao YC, Wang ZQ, Zhang JY, et al. Cancer incidence and risk estimation among medical x-ray workers in China, 1950-1995. Health Phys. 2002 Apr;82(4):455–66.
[20] Jartti P, Pukkala E, Uitti J, Auvinen A. Cancer incidence among physicians occupationally exposed to ionizing radiation in Finland. Scand J Work Environ Health. 2006 Oct;32(5):368–73.
[21] Valone LC, Chambers M, Lattanza L, James MA. Breast Radiation Exposure in Female Orthopaedic Surgeons. The Journal of Bone and Joint Surgery. 2016 Nov 2;98(21):1808–13.
[22] Hurley RJ, McCabe FJ, Turley L, Maguire D, Lucey J, Hurson CJ. Whole-body radiation exposure in Trauma and Orthopaedic surgery. Bone & Joint Open. 2022 Nov 1;3(11):907–12.
[23] Van Nortwick SS, Leonard DA, Finlay AK, Chou L, Valone LC. Methods for Reducing Intraoperative Breast Radiation Exposure of Orthopaedic Surgeons. Journal of Bone and Joint Surgery. 2021 Sep 1;103(17):1646–51.