Basic Study
Copyright ©The Author(s) 2021. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Orthop. Aug 18, 2021; 12(8): 548-554
Published online Aug 18, 2021. doi: 10.5312/wjo.v12.i8.548
Fibula pro-tibia vs standard locking plate fixation in an ankle fracture saw bone model
Tosan Okoro, Kar Hao Teoh, Hiro Tanaka
Tosan Okoro, Department of Arthroplasty, Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Foundation Trust, Oswestry SY10 7AG, United Kingdom
Kar Hao Teoh, Department of Orthopaedic Surgery, Princess Alexandra Hospital NHS Trust, Harlow CM20 1QX, United Kingdom
Hiro Tanaka, Department of Orthopaedics, Royal Gwent Hospital, Newport NP20 2UB, United Kingdom
Author contributions: Okoro T contributed study design, performance of biomechanical testing, analysis of results, drafting and proof reading of manuscript; Teoh KH contributed study design, analysis of results, drafting and proof-reading of manuscript; Tanaka H contributed study design, supervision of study, analysis of results, drafting and proof reading of manuscript.
Supported by Research Grant Provided by AOUK.
Institutional review board statement: This was a biomechanical study and did not involve human and the use of animals.
Conflict-of-interest statement: The authors have no conflict of interest to declare.
Data sharing statement: No additional data are available.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Tosan Okoro, BSc, FRCS, MBChB, PhD, Doctor, Surgeon, Department of Arthroplasty, Robert Jones and Agnes Hunt Orthopaedic Hospital NHS Foundation Trust, Gobowen, Oswestry SY10 7AG, United Kingdom. tosanwumi@hotmail.com
Received: February 9, 2021
Peer-review started: February 9, 2021
First decision: June 25, 2021
Revised: July 2, 2021
Accepted: August 2, 2021
Article in press: August 2, 2021
Published online: August 18, 2021
Abstract
BACKGROUND

Locking plate fixation in osteoporotic ankle fractures may fail due to cut-out or metalwork failure. Fibula pro-tibia fixation was a technique prior to the advent of locking plates that was used to enhance stability in ankle fractures by achieving tri or tetra-cortical fixation. With locking plates, the strength of this fixation construct can be further enhanced. There is lack of evidence currently on the merits of tibia-pro-fibula augmented locking plate fixation of unstable ankle fractures.

AIM

To assess if there is increased strength to failure, in an ankle fracture saw bone model, with a fibula pro-tibia construct when compared with standard locking plate fixation.

METHODS

Ten osteoporotic saw bones with simulated supination external rotation injuries were used. Five saw bones were fixed with standard locking plates whilst the other 5 saw bones were fixed with locking plates in a fibula pro-tibia construct. The fibula pro-tibia construct involved fixation with 3 consecutive locking screws applied across 3 cortices proximally from the level of the syndesmosis. All fixations were tested in axial external rotation to failure on an electromagnetic test frame (MTS 858 Mini-Bionix test machine, MTS Corp, Eden Praire, MN, United States). Torque at 30 degrees external rotation, failure torque, and external rotation angle at failure were compared between both groups and statistically analyzed.

RESULTS

The fibula pro-tibia construct demonstrated a statistically higher torque at 30 degrees external rotation (4.421 ± 0.796 N/m vs 1.451 ± 0.467 N/m; t-test P = 0.000), as well as maximum torque at failure (5.079 ± 0.694N/m vs 2.299 ± 0.931 N/m; t-test P = 0.001) compared to the standard locking plate construct. The fibula pro-tibia construct also had a lower external rotation angle at failure (54.7 ± 14.5 vs 67.7 ± 22.9).

CONCLUSION

The fibula pro-tibia locking plate construct demonstrates biomechanical superiority to standard locking plates in fixation of unstable ankle fractures in this saw bone model. There is merit in the use of this construct in patients with unstable osteoporotic ankle fractures as it may aid improved clinical outcomes.

Keywords: Unstable ankle fractures, Pro-tibia fixation, Improved stability, Simulated biomechanical analysis, Osteoporotic fractures, Ankle injuries

Core Tip: Locking plate fixation in osteoporotic ankle fractures may fail due to cut-out or metalwork failure. This study compared a fibula pro-tibia construct to standard locking plate fixation in an ankle fracture saw bone model. The fibula pro-tibia construct demonstrated biomechanical superiority and there is merit to consideration of its use in patients with unstable osteoporotic ankle fractures.