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Bone Ninja Mobile App for Reverse Planning Method in Internal Limb Deformity and Lengthening Surgery.
Alec Lik-Hang Hung1, Philip K McClure2, Jeanne M Franzone3
1Department of Orthopedics and Traumatology, Prince of Wales Hospital, Chinese University of Hong Kong, Hong Kong.
Strategies in Trauma and Limb Reconstruction
|August 4, 2020
Summary
Bone Ninja, a digital tool, offers accurate reverse planning for intramedullary limb lengthening and deformity correction surgery. This mobile app provides a practical alternative to traditional methods, enhancing surgical planning.
Area of Science:
- Orthopedic surgery
- Limb reconstruction
- Digital surgical planning
Background:
- Motorized intramedullary (IM) lengthening devices are increasingly used for limb lengthening, offering advantages over external fixators.
- Precise preoperative planning is crucial to prevent mechanical axis deviation in femur lengthening procedures.
- The established Reverse Planning Method (RPM) by Baumgart ensures accurate limb length, angulation, and translation correction but traditionally requires cumbersome paper tracings.
Purpose of the Study:
- To evaluate the reliability of the Bone Ninja (BN) mobile application as a tool for teaching and performing the Reverse Planning Method (RPM).
- To assess BN's suitability for planning implantable intramedullary (IM) limb-lengthening procedures and deformity correction surgery.
Main Methods:
- The study utilized the Bone Ninja (version 4.2) mobile application on an iPad mini.
- The RPM steps and terminology, as originally described by Baumgart, were performed using the BN app.
- Measurements and planning were conducted digitally, comparing the app's functionality to traditional methods.
Main Results:
- Bone Ninja demonstrated accuracy comparable to Picture Archiving and Communication Systems (PACS) for limb length and deformity angle measurements.
- The digital RPM using BN proved to be a simple and validated method for deformity correction.
- The app facilitated the RPM process, offering a feasible and practical alternative to manual paper-based planning.
Conclusions:
- Bone Ninja is a reliable and validated digital tool for deformity correction in orthopedic surgery.
- It serves as a practical and convenient alternative to traditional paper-and-pencil methods for applying the RPM in IM limb lengthening and deformity correction.
- The digitized RPM using BN enhances surgical planning feasibility and practicality for internal limb lengthening surgeries.
