Total elbow arthroplasty (TEA) is a definitive surgical procedure for treating rheumatoid arthritis and (posttraumatic) osteoarthritis of the elbow and is also useful in comminuted elbow fractures. Pre-operative digital templating may theoretically improve the surgical implantation of TEA, but reliability and predictive values of templating are unknown. The aim of this study was to determine the intra- and inter-observer reliability and the validity of pre-operative digital templating for TEA.
All pre-operative plain anterior-posterior and lateral calibrated elbow radiographs from patients who underwent TEA in our center from 2008 to June 2014 were reviewed. Two independent assessors templated implant sizes using digital overlays twice. Intra- and inter-observer reliability were evaluated with Cohen's kappa. Two experienced elbow surgeons reviewed post-operative radiographs for evaluation. The predictive value of templating was the percentage of the correctly templated sizes, with the optimal implant size as the reference standard.
Twenty-one cases were included. Intra-observer reliability was substantial to almost perfect (κ = 0.61 and κ = 0.90) for humeral implants, moderate to substantial (κ = 0.54 and κ = 0.73) for ulnar implants. Inter-observer reliability was substantial (κ = 0.67) for humeral implants and moderate (κ = 0.60) for ulnar implants. The predictive value was 53 % for both implants.
Pre-operative digital templating for TEA is a reliable method to plan implant sizes. However, the predictive value is low.