The present study had several limitations. First, the study assessed only the reliability of the qualification of the glenoid bone defect without considering the location and type of defect, which might affect the measurement reliability. Second, variation in the training and experience of the three observers might be one of the reasons for the inter-observer variations in measurement.
In conclusion, it is more reliable to measure the glenoid defect using areal measurement than linear measurement. However, the reliability of the measurements of areal bone defect is moderate or worse. Thus, there is a need for the development of a more accurate and objective measurement method in the determination of the en-face view and best-fit circle. Subjective factors affecting the measurement of glenoid bone loss should be eradicated as much as possible.
We thank the experts from the Department of Radiology and Epidemiology for providing CT data and statistical analysis.
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