The Inter- and Intra-observer Reliability of Three Methods for Evaluating Carpal Collapse

Kienbock’s disease is a rare and debilitating condition. The decision for surgical intervention majorly depends on the extent of the carpal collapse. Therefore, the accurate measurement of carpal collapse is of critical importance. 

The current study assessed the inter and intra-observer reliability of the three most frequent methods in measuring carpal height and determining carpal collapse. 

Fifty-Nine photocopied radiograms were reviewed by three observers (one senior orthopedic resident, one fellowship-trained hand surgeon, and one senior radiology resident) at 3 consecutive time points. Besides, one-week intervals were considered between the evaluations. The evaluated measures included the Carpal Height Ratio (CHR), Revised Carpal Height Ratio (RCHR), and Capitate-Radius (CR) index. The reliability of the measurements in determining the carpal height was examined using the Intraclass Correlation Coefficient (ICC). The agreement of the measures on determining the presence or absence of the carpal collapse was assessed by Cohen’s Kappa (K) value.

The overall inter and intra-observer reliability of the CR index in quantifying the carpal collapse was measured as 0.863 and 0.942, respectively. The overall inter and intra-observer reliability of CHR in quantifying the carpal collapse was computed to be 0.615 and 0.891, respectively. The overall inter and intra-observer reliability of RCHR in quantifying the carpal collapse equaled 0.412 and 0.792, respectively. The overall K for determining the presence or absence of a carpal collapse was calculated as 0.776, 0.683, and 0.549 for CR index, CHR, and RCHR, respectively.

The CR index is the most reliable approach to measure carpal height. Furthermore, it is appropriate for determining the presence or absence of carpal collapse.