Description
The objective of this study was to assess the reliability of glenoid track measurements by CT and MRI. We hypothesized that CT and MRI would have equivalent reliability. A cohort of 46 patients with Hill-Sachs lesions following anterior shoulder dislocations were collected. Glenoid circumference using a best-fit circle, anterior bone loss, and Hill-Sachs interval were assessed by a sport medicine fellow and an orthopaedic surgeon. CT and MRI did not demonstrate similar reliability regarding measurements of the glenoid track. Based on the results of our study, MRI showed a higher interrater reliability across multiple measurements. This may be due to the lower number of slices per MRI for raters to assess. The larger number of slices available for analysis in CT may lead to lower reliability between raters. The additional measurement of HSI may have contributed to decreased reliability when compared to current literature on measurement reliability of anterior glenoid bone loss. Poor reliability between CT measurements of the glenoid track may potentially affect clinical decisions. While MRI demonstrated better interrater reliability, the discrepancy between CT and MRI in the same individual implies that the modalities are not equivalent for calculating the glenoid track.
