Planning software and patient-specific instruments in shoulder arthroplasty.

Computer planning software and patient-specific instrumentation have been investigated in multiple subspecialties of orthopedics with mixed results. Shoulder arthroplasty has evolved over the last decade with improvements in implant design and surgical instrumentation. Despite these advances, glenoid positioning in shoulder arthroplasty continues to be a difficult problem. Recent advances in three-dimensional imaging techniques and the use of computer planning software may potentially address some of the common difficulties encountered by surgeons. The addition of patient-specific instrumentation and guides provide an option for patients with significant glenoid deformity that may allow improved accuracy of glenoid component implantation compared to using standard instrumentation. Studies have reported improved positioning of the glenoid component in both anatomic and reverse total shoulder arthroplasty with patient-specific instrumentation and guides. More research is needed to determine whether these improvements lead to better patient-reported outcomes or implant survival. In addition, further studies will be needed to address whether this technology is cost effective for large-scale implementation in the orthopedic community.