Abstract
Introduction: The increasing popularity of minimal access surgery in orthopaedic surgery has resulted in increasing use of intra-operative fluoroscopy. The radiation dose received by the surgeon varies from procedure to procedure depending on several factors such as duration of procedure, direct exposure to radiation beam and distance from the radiation source. In particular hand and wrist injuries often involve direct fluoroscopic exposure to the hands of the surgeon and assistant during the procedure.
Aim: We undertook a prospective study to directly evaluate the exposure of the surgeon’s and assistant’s hands and thyroid glands during K-wiring procedures of the hand and wrist. In addition we evaluated the efficacy of a lead thyroid shield in limiting the radiation dose to the thyroid gland. In addition we undertook a questionnaire of orthopaedic surgeons and trainees in Ireland to assess the availability of thyroid shields and current practice in wearing them.
Method A total of 30 cases were evaluated. Dosimeter film badges (TLD) were obtained from the Radiological Protection Institute of Ireland (RPI). Two dosimeters were worn by each of the surgical team: one on the dorsum of the dominant hand and a second worn on the neck during the procedure. The number of fluoroscopic exposures, number of times that hands were caught in the image field, the total dosage of radiation for the procedure and the length of time of exposure were recorded. In 20 cases the surgical team undertook standard precautions of a lead jacket. In a random selection of 10 cases the surgical team also wore a thyroid shield.
Results. The mean dose to the surgical teams’ hands was 1.8 cGy (95% CI + 0.6). The mean dose to the thyroid gland was 0.6 cGy in unprotected cases. Notably the dose to the assistants’ hands was higher though this did not reach statistical approval. In cases in which a thyroid shield was worn a significant decrease in dose was noted (p< 0.05). 35% of surgeons had completed a radiation protection course with junior trainees being less likely to have completed such a course.
Conclusion: Significant cumulative radiation dose to the hands and thyroid gland occurs following K-wiring of extremities. The dose to the thyroid gland can be effectively decreased by the use of a thyroid collar. Junior trainees whose operative times and hence radiation exposure are higher, have limited radiation protection training. The mandatory use of thyroid shields and early introduction of radiation protection training may help minimise further radiation exposure.
The abstracts were prepared by Emer Agnew, Secretary to the IOA. Correspondence should be addressed to him at Irish Orthopaedic Association Secretariat, c/o Cappagh National Orthopaedic Hospital, Finglas, Dublin 11, Ireland.
