Highly-versatile variable-angle bone plate system

A bone plate system for securing a bone plate to bone, the system comprising:

• a bone plate having an upper surface, a lower bone-engaging surface, and an hourglass-shaped hole extending therethrough from the upper surface to the lower surface, the hole having an inner surface that defines a circumference of the hole, the hole defining a central axis and being configured and dimensioned to receive a bone screw therein, wherein:
• the bone plate has a plurality of discrete columns of protrusions arranged on the inner surface of the hole and spaced apart from one another around the circumference, each column extending in a direction from the upper surface to the lower surface;
• and
• the protrusions on the columns being configured, dimensioned and spaced apart from one another around the circumference by a distance selected to permit the protrusions to engage a thread on a head of a bone screw inserted into the hole to lock the bone screw at a selectable angle within a range of selectable angles forming a cone of angulation around the central axis of the hole.