Ankle fusion percutaneous home run screw fixation: Technical aspects and soft tissue structures at risk

Pseudoaneurysm of the Peroneal Artery After Ankle Arthrodesis Treated by Endovascular Coil Embolization: A Case Report

CASE

Pseudoaneurysms of the peroneal artery around the ankle joint have rarely been reported. We present the case of a 64-year-old man with a pseudoaneurysm of the anterior perforating branch of the peroneal artery associated with a screw inserted from the anterolateral distal tibia during ankle arthrodesis. Endovascular treatment with selective catheterization and coil embolization was successfully performed. The ankle joint achieved bone union without delay, and the pseudoaneurysm did not recur at the 18-month follow-up.

CONCLUSION

This is the first report describing a pseudoaneurysm of the peroneal artery after ankle arthrodesis. Successful outcomes can be achieved by endovascular treatment.

Finite element analysis of the initial stability of arthroscopic ankle arthrodesis with three-screw fixation: posteromedial versus posterolateral home-run screw

Objective

Arthroscopic ankle arthrodesis (AAA) is a standard surgical method for the treatment of advanced traumatic ankle arthritis and has become more popular due to its advantages. To fix the tibiotalar joint, the use of three percutaneous screws is considered to have better mechanical stability than the use of two screws. However, it is sometimes difficult to insert three screws because they might block each other due to the small area of the tibiotalar joint surface and the large diameter of the screws; few articles illustrate how to insert three screws without the screws disturbing each other. The purpose of this study is to explore possible screw configurations of tripod fixation in arthroscopic ankle arthrodesis that avoid the collision of screws and yield better biomechanical performance.

Methods

We used the finite element method to examine the impact of different screw positions and orientations on the biomechanical characteristics of a three-dimensional (3D) ankle model. Maximum and average micromotion, pressure on the articular surface, and von Mises stress values of the tibia and the talus were used to evaluate the initial stability of the ankle.

Results

Five kinds of three-screw configurations were identified, and finite element analysis results suggested that configurations with the posteromedial home-run screw presented lower micromotion (maximum, 17.96 ± 7.49 μm versus 22.52 ± 12.8 μm; mean, 4.88 ± 1.89 μm versus 5.19 ± 1.92 μm) (especially configuration 3) and better screw distributions on the articular surface than those with the posterolateral home-run screw.

Conclusion

Screw configurations with the posteromedial home-run screw avoid collision and are more biomechanically stable than those with the posterolateral home-run screw. Thus, inserting the home-run screw through the posteromedial approach is recommended for clinical practice.