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Updated: May 2, 2026

Pedicle Screw Placement Using an Augmented Reality Head-Mounted Display in a Porcine Model
Published on: May 24, 2024
A novel technique for accurate Poller (blocking) screw placement
Andrew Hannah1, Tariq Aboelmagd1, Grace Yip1
1Department of Trauma and Orthopaedics, Cambridge University Hospitals NHS Foundation Trust, Addenbrooke's Hospital, Hills Road, Cambridge CB2 0QQ, United Kingdom.
Abstract:
Achieving good results with intramedullary nailing of oblique long bone fractures at the metaphyseal-diaphyseal junction can be difficult. There is a strong tendency for axial displacement and an association with characteristic malalignment of the short fragment. Poller or blocking screws have been shown to be effective in aiding fracture reduction. While several papers describe methods for screw placement, these are confusing to understand, difficult to follow in clinical practice and not always applicable. Here we describe a new, simple, reproducible and easy to use method for ensuring accurate Poller screw placement, in order to maximise the benefits of their use and achieve good overall results.
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