Implant with improved flow characteristics

A method of making an intervertebral implant having a body, the body having an open truss structure, the body including opposing end surfaces, and a perimeter surface, the perimeter surface extending around an outer periphery of the body;

• the body also including a central portion and a peripheral portion, the peripheral portion extending from the perimeter surface inward toward the central portion;
• the method of making comprising the steps of:
• additively manufacturing a first layer, the first layer being proximate a base plate;
• the first layer forming a part of the perimeter surface;
• continuing to additively manufacture the body layer by layer wherein each successive layer is disposed further from the base plate than the previous layer so that the body is built vertically upward layer by layer, thereby producing:
• a generally annular shape with opposing end surfaces, the opposing end surfaces including a superior surface and an inferior surface,
• a first strut disposed at a boundary between the central portion and the peripheral portion and having a non-circular cross-sectional shape, the non-circular cross-sectional shape being one of oblong and an airfoil cross-sectional shape, and the non-circular cross-sectional shape having a cross-sectional length and a cross-sectional width, wherein the cross-sectional length is longer than the cross-sectional width;
• and
• wherein the first strut is oriented such that the cross-sectional length of the first strut extends in a radial direction extending from a center of the central portion to the peripheral portion in order to facilitate flow of bone graft material in the radial direction away from the central axis.