| 摘要 |
A pedicle screw comprises a head. A shaft is joined to the head. The shaft comprises a first threaded portion, a middle portion and a second threaded portion. The middle portion comprises a modified threaded portion being configured to mitigate damage to a patient's nerve root. A first marker is joinable to the shaft proximate the modified threaded portion. The first marker comprises a material being radiographically distinguishable from the shaft in which a placement of the modified threaded portion is observable. |
