10 3D-printed medical devices having a gyroid structure; surgical instruments; 3D-printed surgical implants, custom surgical implants, and surgical implants having a gyroid structure, namely, implants for upper and lower extremities; 3D printed medical devices, surgical implants, custom surgical implants, and surgical implants having a gyroid structure for orthopedic and spinal conditions produced by additive manufacturing, namely, stereolithography or powder bed fusion