Intraoperative measurement after excision of distal clavicle: Correlation with postoperative radiographs

Background: Injury to the acromioclavicular joint is a common diagnosis among the military population causing significant shoulder pain and disability. Once nonoperative modalities are exhausted excision of the distal clavicle is indicated. Arthroscopic technique has led to decreased morbidity, earlier return to activity, and improved cosmesis compared with open techniques. However, a postoperative radiograph is used to determine the amount of distal clavicle resected. This study attempts to validate the intraoperative measurement with the postoperative radiograph to reduce health care cost and patient radiation exposure. Methods: The charts of 19 arthroscopic excisions of the distal clavicle were retrospectively reviewed from September 2007 through March 2009. The amount of distal clavicle excised as noted on postoperative radiographs in the postanesthesia care unit was measured by four separate observers blinded to the patients' identifiable information and the intraoperative measurement from the patients' operative report. The radiographic measurements were compared to the intraoperative measurements using interclass correlation coefficients and Bland-Altman analysis to determine interrater and intrarater reliability. Results: The intrarater reliability for each radiographic observer had a mean interclass correlation coefficient of 0.89 (0.82-0.96). The interrater reliability comparing the different radiographic observers had a mean interclass correlation coefficient of 0.88 (0.77-0.94). The interclass correlation coefficient comparing the radiographic measurement and the interoperative measurement was 0.81 (0.71-0.86). Bland-Altman analysis showed that the interoperative and postoperative radiographic measurement can reliably come within 3 mm of each other. Conclusions: The intraoperative and radiographic method can be reliably used interchangeably to determine the amount of distal clavicle excised.