A review of patient matched implants for shoulder arthroplasty.

Background: Advances in technology have enabled implant designers and shoulder surgeons to strive towards improving implant survival and patient outcomes. Patient matched implants (PMIs) for arthroplasty have developed from the use of technologies such as computer aided design and computer-aided manufacturing technology and three-dimentional printing. Methods: We conducted a computerized search of the electronic databases. We included studies which reported on PMI used in shoulder arthroplasty. Data were extracted by authors, publication year, study level, study type, demographic data (age, sex, sample size), type of arthroplasty, follow-up time, and outcomes. Results: 5 studies were identified as being eligible for this analysis. 55 patients and 57 shoulders were included. The average age was 72.3 across 5 studies. Average follow-up was 28.26 months. 22/57 (39%) were for primary shoulder arthroplasty and 35/57 (61%) were revision procedures. 50/56 (89%) of shoulders improved. 7/56 (13%) of shoulder had a complication. Discussion: PMI for shoulder arthroplasty has so far only been used for severe glenoid bone loss in primary and revision shoulder arthroplasty. PMI can not only be used in the severe glenoid bone loss patient but there are some advantages to using it in the regular patient who attends seeking a shoulder arthroplasty. A limitation of our review is that there are no studies published on PMI for primary shoulder arthroplasty without significant glenoid bone loss. A paradigm shift in shoulder arthroplasty may occur where PMI is not only used for glenoid bone loss and challenging revision cases but also in primary shoulder arthroplasty without significant bone loss.