Statistical shape model of the talus bone morphology: A comparison between impinged and nonimpinged ankles

Abstract

Diagnosis of ankle impingement is performed primarily by clinical examination, whereas medical imaging is used for severity staging and treatment guidance.The association of impingement symptoms with regional three-dimensional (3D) bone shape variaties visible in medical images has not been systematically explored, nor do we know the type and magnitude of this relation. In this cross-sectional case-control study, we hypothesized that 3D talus bone shape could be used to quantitatively formulate the discriminating shape variations between ankles with impingement from ankles without impingement, and we aimed to characterize and quantify these variations. We used statistical shape modeling (SSM) methods to determine the most prevalent modes of shape variations that discriminate between the impinged and nonimpinged ankles. Results of the compactness and parallel analysis test on the statistical shape model identify 8 prominent shape modes of variations (MoVs) representing approximately 78% of the total 3D variations in the population of shapes, among which two modes captured discriminating features between impinged and nonimpinged ankles (p value of 0.023 and 0.042). Visual inspection confirms that these two shape modes, capturing abnormalities in the anterior and posterior parts of talus, represent the two main bony risk factors in anterior and posterior ankle impingement. In conclusion, in this research using SSM we have identified shape MoVs that were found to correlate significantly with bony ankle impingement. We also illustrated potential guidance from SSMs for surgical planning.

CT‐Based Calculation Model Assists Precise Treatment for Anterior and Posterior Ankle Bony Impingement

“…Arbabi et al 12 created a statistical shape model (SSM) of the talus bone morphology of impinged and nonimpinged ankles through a complex algorithm. This is a sophisticated technique which helps to group and characterize variants of the coincident shape as a group of discrete components.…”

“…This information allows the complete removal of osteophytes and can lead to good surgical results 8 . Arbabi et al 12 created the statistical shape model of the talus bone morphology through complex algorithms, demonstrated the feasibility of 3D SSMs to quantitatively characterize the specific 3D shape variations of talus bones, capturing of modes of shape variations that correlate with ankle impingement as objectified in surgical reports. Obviously, the use of standardized models has very limited reference significance for specific surgeries, but the author provides us with a feasible modeling method.…”

Multi-level multi-domain statistical shape model of the subtalar, talonavicular, and calcaneocuboid joints

“…Using SSM, a statistical model can be created to compare mean bone shape morphology and identify anatomical modes of variation. Previous ankle SSM studies have been limited to a single bone and could not, therefore, evaluate multi-domain joint relationships ( Melinska et al, 2015 ; Melinska et al, 2017 ; Tümer et al, 2019a ; Tümer et al, 2019b ; Gabrielli et al, 2020 ; Krähenbühl et al, 2020 ; Liu et al, 2020 ; Schmutz et al, 2021 ; Arbabi et al, 2022 ; Peiffer et al, 2022 ; Vafaeian et al, 2022 ). A multi-domain technique can be implemented to capture morphological and alignment changes for multiple bones throughout a population.…”