The accuracy of digital templating in uncemented total hip arthroplasty.

We analyzed the reproducibility and reliability of computer templating in primary uncemented total hip arthroplasties as compared to standard onlay templating techniques with hardcopy radiographs from a digital source. Digital templating showed good intraobserver and interoberserver reliability with intraclass correlation coefficient values greater than 0.7. Using computer templating, prediction of sizing to within 1 size was 85% accurate for femoral stem sizing and 80% accurate for acetabular sizing. Using onlay templating, prediction of sizing to within 1 size was 85% accurate for femoral sizing and 60% accurate for acetabular sizing. We conclude that the introduction of digital templating has significant benefits in preoperative planning for total hip arthroplasty over onlay templating.