A spinal anchor system (10) comprising spinal anchors (16), each of which including a proximal portion (30), a distal bone engaging portion (32), a passage (34) extending from an opening in the proximal portion to the distal bone engaging portion, and an opening (36) in a sidewall of the distal bone engaging portion, the opening communicating with the passage； a screw extension (517) connectable to one of the bone anchors； a bone cement delivery system (18)； a cement delivery tube (814) having a proximal end (856) connectable to the bone cement delivery system and a distal end (854) sized to be positioned within the passage of the distal bone engaging portion of a spinal anchor； and an anchor connection instrument (800) having an instrument body (802) having a proximal end (806), a distal end (804), and a passage therebetween for receiving the cement delivery tube, the distal end including a first connection feature (810) configured to connect to the proximal portion of one of the bone anchors and a second connection feature (812) configured to connect to the distal bone engaging portion of the spinal anchor.
