Custom Implants and Patient-Specific Instrumentation in Total Shoulder Arthroplasty.

Patients with complex anatomy and osseous deformity undergoing primary and revision total shoulder arthroplasty can pose challenges to surgeons and render off-the-shelf implants insufficient. The advent of three-dimensional printing has enabled the emergence of patient-specific instrumentation and custom implants which offer tailored solutions to address each patient's unique anatomy. This article examines the principles, indications, and clinical outcomes of patient-specific instrumentation and custom implants in total shoulder arthroplasty.