Modular uniplanar pedicle screw assembly for use with a polyaxial bone fastener

A method of using a modular uniplanar pedicle screw assembly on a polyaxial bone fastener that has been inserted into a vertebra, the method comprising:

• inserting a lower portion of an adapter into a recess arranged on a spherical head of the bone fastener;
• inserting an upper portion of the adapter into a longitudinal slot of a uniplanar tulip assembly, wherein the upper portion extends from the lower portion, the upper portion having an upper surface, a pair of oppositely positioned lateral surfaces extending from the upper surface, an a pair of oppositely positioned inclined surfaces extending from the upper surface, the inclined surfaces are received in the longitudinal slot, thereby allowing movement of the uniplanar tulip assembly in a first plane a long a direction that is parallel to a longitudinal axis of the longitudinal slot, and the longitudinal slot preventing movement of the uniplanar tulip assembly in a second plane lateral to the first plane relative to the bone fastener;
• attaching a fusion bar to the uniplanar tulip assembly;
• and
• moving the vertebrae to a desired position in the second plane using the uniplanar tulip assembly with the inserted adapter and the attached fusion bar.

A method of using a modular uniplanar pedicle screw assembly, the method comprising:

• inserting a bone fastener into a vertebra, the bone fastener having a spherical head defining a recess and a shaft extending from the head;
• attaching a uniplanar tulip assembly to the head of the bone fastener, the uniplanar tulip assembly comprising a detachable tulip having a bottom opening for receiving the head of the bone fastener, a saddle having an upper surface and a lower surface and defining a longitudinal slot extending through the saddle from the upper surface to the lower surface, and a clamp defining a non-linear slot;
• inserting a lower portion of an adapter into a recess arranged on the head of the bone fastener;
• and
• inserting an upper portion of the adapter into the longitudinal slot of the uniplanar tulip assembly, the upper portion having an upper surface, a pair of oppositely positioned lateral surfaces extending from the upper surface, and a pair of oppositely positioned inclined surfaces extending from the upper surface, the inclined surfaces configured to be received into the longitudinal slot of the saddle to allow movement of the uniplanar tulip assembly in a first plane along a direction that is parallel to a longitudinal axis of the longitudinal slot, the longitudinal slot preventing movement of the uniplanar tulip assembly in a second plane lateral to the first plane relative to the bone fastener.