The 50 % rule technique for guidewire placement in minimally invasive bunion surgery

Abstract

Minimally Invasive Bunion Surgery (MIBS) continues to gain popularity with advancements in fixation systems, although there continues to be a steep learning curve associated with this procedure. This study aims to provide an additional technique to facilitate the placement of accurate and reproducible guidewires for screw fixation. As achieving the desired alignment with the proximal guidewire can be challenging, this study focuses on a reproducible technique that adheres to the important stability principles of MIBS.

This technique describes pre-operative planning for guidewire placement referred to as establishing the “cross-hairs and gunsights”. This provides external visualization to aid in guidewire placement. The 50% rule provides a landmark on lateral x-ray that allows for initial wire placement along the lateral cortex for efficient and accurate positioning that correlates with the expected capital fragment translation.