Modular screw

A modular screw comprising:

• a post including a tapered portion extending along a portion of a length of the post, the post defining a first bore;
• and
• a head assembly adjustably coupled with the post, the head assembly including:
• a head defining a slot configured to receive a spinal rod therein;
• an elongate screw having external threads extending along a portion of a length of the elongate screw;
• and
• a screw shank defining a second bore defining internal threads configured to engage the external threads of the elongate screw when the elongate screw is received within the second bore of the screw shank, the screw shank including a shaft having a keyed outer surface including a longitudinal ridge and an engaging portion provided with a gripping surface, the engaging portion configured to expand radially outward when the elongate screw engages the engaging portion,
• wherein at least a portion of the screw shank is dimensioned to be selectively received in the first bore of the post.