Abstract
Introduction: The mini C-arm is a compact, user-friendly device with the advantage of reducing exposure to ionising radiation compared to the conventional C-arm. Optimising radiation exposure is not only desirable, but also a legal requirement and protocols should be in place to achieve this. The purpose of this paper is to review our use of the mini C-arm for elective foot surgery and to suggest guidelines for optimising its use.
Materials and Methods: Between 2004 and 2006, all elective foot surgery requiring intraoperative imaging were performed using the mini C-arm unit. Procedures performed included ankle, midfoot and hindfoot arthrodeses and joint injections or aspirations. Screening times and radiation doses were recorded for each procedure.
Results: Following an initial learning curve, the screening times stabilised around the median value for the individual procedures. For a subtalar or triple arthrodesis this was less than 60 seconds, for ankle arthrodesis, less than 90 seconds and for hindfoot arthrodesis using a nail, less than 100 seconds. Other single joint arthrodeses had a screening time under 30 seconds and injections or aspirations, under 12 seconds.
Discussion: As screening time is the main variable that can be controlled by the surgeon, assuming that all other precautions are followed, screening time can be used as a useful audit tool to measure optimum use of the mini C-arm. A protocol is presented which includes completion of an audit form for every operation where the mini C-arm is used. The above times can be used as a guide to enable hospital trusts to formulate their own protocols to regulate radiation exposure.
Conclusion: The mini C-arm is well suited for foot and ankle surgery. Having a protocol in place and periodic audit is essential to optimise its use. Apart from being good clinical practice, this is now a legal requirement.
Results: In males CA was significantly larger in all regions of the foot than in females. There were no significant between sex differences in PP, CT and PTI. FTI was significantly greater in males than females for most regions in the foot. IPP was earlier in females. MaxF was also significantly higher in males in all the regions except the 2nd toe. MeanF was also higher in males.
Conclusion: There were no PP differences; however the plantar surface area of the male foot was larger than females.
Correspondence should be addressed to: D. Singh, BOFAS, c/o BOA, The Royal College of Surgeons, 35–43 Lincoln’s Inn Fields, London WC2A 3PE.
