Statistical shape modeling of the talocrural joint using a hybrid multi-articulation joint approach

Nicola Krähenbühl,Andrew C Peterson,Alexej Barg,Amy L Lenz,Charles L Saltzman,Rich J Lisonbee,Andrew E Anderson,Beat Hintermann

doi:10.1038/s41598-021-86567-7

Abstract

Historically, conventional radiographs have been the primary tool to morphometrically evaluate the talocrural joint, which is comprised of the distal tibia, distal fibula, and proximal talus. More recently, high-resolution volumetric imaging, including computed tomography (CT), has enabled the generation of three-dimensional (3D) reconstructions of the talocrural joint. Weightbearing cone-beam CT (WBCT) technology provides additional benefit to assess 3D spatial relationships and joint congruency while the patient is load bearing. In this study we applied statistical shape modeling, a computational morphometrics technique, to objectively quantify anatomical variation, joint level coverage, joint space distance, and congruency at the talocrural joint. Shape models were developed from segmented WBCT images and included the distal tibia, distal fibula, and full talus. Key anatomical variation across subjects included the fibular notch on the tibia, talar trochlea sagittal plane rate of curvature, tibial plafond curvature with medial malleolus prominence, and changes in the fibular shaft diameter. The shape analysis also revealed a highly congruent talocrural joint with minimal inter-individual morphometric differences at the articular regions. These data are helpful to improve understanding of ankle joint pathologies and to guide refinement of operative treatments.

Highlights

Conventional radiographs have been the primary tool to morphometrically evaluate the talocrural joint, which is comprised of the distal tibia, distal fibula, and proximal talus
With little differences seen on the medial aspect, this led to a trapezoidal versus rectangular shape for the tibial
Statistical shape modeling (SSM) of the bones of the ankle were performed on 2D radiographs using manual landmark selection[21]

Summary

Introduction

Conventional radiographs have been the primary tool to morphometrically evaluate the talocrural joint, which is comprised of the distal tibia, distal fibula, and proximal talus. In this study we applied statistical shape modeling, a computational morphometrics technique, to objectively quantify anatomical variation, joint level coverage, joint space distance, and congruency at the talocrural joint. Numerous 2D measurements have been developed in attempt to quantify normal and pathological anatomy within the ankle joint, distal syndesmosis and medial/lateral g utter[4,5,6] These complex three-dimensional (3D) morphologies are not adequately represented in single 2D measurements that are most often isolated to a single imaging plane[7]. The objective of the present study was to develop a talocrural joint level SSM to evaluate shape variances in combination with joint coverage, distance and congruency based on cone-beam WBCT. The presented model should serve as a reference for future research focusing on ankle or hindfoot pathologies

Objectives

Methods

Results

Conclusion