Duocentric® reversed shoulder prosthesis and Personal Fit® templates: innovative strategies to optimize prosthesis positioning and prevent scapular notching.

We describe our experience with a new system of patient-specific template called Personal Fit(®), which is unique in shoulder surgery and used in combination with Duocentric(®) prosthesis. The reverse prosthesis's concept is the invention of Paul Grammont, developed with Grammont's team of Dijon University as from 1981, which led to the first reversed total shoulder prosthesis called Trumpet in 1985. The Duocentric(®) prosthesis developed in 2001 is the third-generation prosthesis, coming from the Trumpet and the second-generation prosthesis Delta(®) (DePuy). This prosthesis provides a novel solution to the notching problem with an inferior overhang integrated onto the glenoid baseplate. Personal Fit(®) system is based on reconstructing the shoulder joint bones in three dimensions using CT scan data, placing a landmark on the scapula and locating points on the glenoid and humerus. That will be used as a reference for the patient-specific templates. We study the glenoid position planned with Personal Fit(®) software relative to native glenoid position in 30 cases. On average, the difference between the planned retroversion (or anteversion in one case) and native retroversion was 8.6°.