RADIATION EXPOSURE TO THE HANDS AND THE THYROID OF THE SURGEON DURINGINTRAMEDULLARY NAILING

During 41 procedures of intramedullary nailing of femoral and tibial f ractures, the primary surgeon and the first assistant wore ring dosime ters on their dominant index fingers. While the average fluoroscopy ti me per procedure was 4.6 min, the average dose of radiation to the dom inant hand of the primary surgeon was 1.27 mSv to the first assistant. The dose limit for the extremities is 500 mSv per year, as recommende d by the International Commission on Radiological Protection. Extrapol ation of the mean dose of the primary surgeon and first assistant per procedure of 1.23 mSv leads to the result that the recommended dose li mit of 500 mSv would only be exceeded if more than 407 intramedullary nailing procedures are carried out per year. The duration of fluorosco py time correlated with the radiation dose to the hands of the surgeon s, though it was determined by phantom measurements that the majority of radiation exposure occurred during brief exposures of the hands in the direct x-ray beam on the x-ray tube near side of the patient. In o rder to assess the surface doses of the thyroid gland to the primary s urgeon with and without a lead shield, we performed in vitro measureme nts during operative procedures of the lower leg simulating different intraoperative situations under fluoroscopic control. The average regi stered ionizing dosage without a thyroid shield was approximately 70 t imes higher than with thyroid lead protection. In a previous study we found average fluoroscopy times during intramedullary nailing of the t ibia and femur of 4.6 min per procedure. Extrapolation of this value l eads to the result, that even when 1000 intramedullary nailing were ca rried out without wearing lead protection, only 13 percent of the dose limit recommended by the International Commission on Radiological Pro tection for the thyroid of 300 mSv per year would be reached; by weari ng the lead protection only 0.2 percent of the recommended dose would be reached. (C) Published by Elsevier Science Ltd. All rights reserved .