Optimising use of the mini C-arm in foot and ankle surgery.

Background: The mini C-arm reduces 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.

Methods: Since 2004, all elective foot surgery requiring intraoperative imaging was performed using the mini C-arm. Screening times and radiation doses were recorded for each procedure.

Results: Following a learning curve, the screening times stabilised around the median value for the individual procedures. For subtalar or triple arthrodesis this was less than 60 s, for ankle arthrodesis, less than 90 s, for hindfoot arthrodesis using a nail, less than 100 s and for joint injections less than 12 s.

Conclusion: Screening time can be used as an audit tool to measure optimum use of the mini C-arm. A protocol is presented including an audit form for every operation where the mini C-arm is used. Radiation protection issues are addressed.