Dynamic spinal screw-rod connectors

A spinal fixation system comprising:

• two substantially parallel rods, each having a first end and a second end;
• a fixed rod connector engageable to a first vertebra in the spine and having a lower surface and an upper surface and defining a thru-hole, said fixed rod connector immovably fixed to the first end of both of said rods;
• a one-piece dynamic rod connector engageable to a second vertebra in the spine and having a lower surface and an upper surface and defining a thru-hole, said dynamic rod connector slidably engaged to each of said rods and moveable relative to said fixed rod connector to vary the distance between the first and second vertebrae, said dynamic rod connector fixable to said rods to fix the distance between the vertebrae;
• one bolt for each connector, each said bolt having a vertebra engaging portion on a first end and a threaded post on an opposite second end, said post insertable through said thru-holes of said connectors;
• each said bolt including an integral flange between said vertebra engaging portion and said post for supporting a corresponding connector;
• and
• a threaded nut for each of said bolts, one nut engageable to one bolt to secure said fixed rod connector to said one bolt and the other nut enaageable to the other bolt to compress said dynamic rod connector about said rods and to secure said dynamic rod connector to said other bolt.