Could a Kinematic Model Pave the Way for Improvements in PCFD Ligament Reconstruction?

Mania and team, in their Foot and Ankle International study, took a closer look at key features of a ligament reconstruction to help stabilize peritalar subluxation that presents in progressive collapsing foot deformity (PCFD).¹ In this condition, the painful subluxation may result from internal and plantar rotation of the talus on the calcaneus. Traditionally, surgeons have chosen medial soft tissue procedures to address this when bony intervention does not fully do so. However, these authors sought to determine if a subtalar talocalcaneal ligament reconstruction might be a favorable alternative option.¹

The researchers created a 3-dimensional surface model from 10 healthy ankles, from which, they investigated over 1,000 different courses that the subtalar talocalcaneal ligament could take. They simulated various ranges of motion between the talus and calcaneus, along with ligament strain (as a positive length variation).¹ Taking this data, they selected the best combination of features for this simulated reconstruction, including extraarticular talocalcaneal insertion, isometric kinematic behavior in inversion/eversion, and increased length in talar internal rotation.¹ They shared these preferred parameters included a laterodistal orientation of the talar insertion in relation to the subtalar joint axis and laterodistal deviation of the calcaneal insertion.

The authors concluded that their model showed “that a ligament reconstruction in the subtalar space presents a pattern of length variation that may stabilize the internal talar rotation without impeding the physiological subtalar motion.”1                

Reference

1. Mania S, Beeler S, Wirth S, Viehöfer A. Talocalcaneal Ligament Reconstruction Kinematic Simulation for Progressive Collapsing Foot Deformity. Foot Ankle Int. 2023;0(0). doi:10.1177/10711007231213361