DOI: 10.5061/dryad.b5mkkwhqh
title: Data for: Tuning and validation of a virtual mechanical testing pipeline for condylar stress fracture risk assessment in Thoroughbred racehorses

description: Condylar stress fracture of the third metacarpal/metatarsal bone (MC3/MT3)
 in Thoroughbred racehorses is a common catastrophic injury, putting both
 the racehorse and the jockey at risk. Microdamage forms in the distal MC3
 and may result in strain elevation and higher risk of stress fracture,
 directly and through focal osteolysis resulting from the associated damage
 repair by remodelling in the condylar parasagittal grooves (PSG). Standing
 computed tomography (sCT) is a practical screening tool for detecting
 fatigue-induced structural changes, but clinical interpretation remains
 subjective. The goal of this study was to develop and validate an
 sCT-based, subject-specific finite element analysis pipeline for virtual
 mechanical testing of the distal MC3. Twelve (n = 12) MC3
 condyles with available ex vivo strain were selected. Half of the
 specimens were used for tuning Young’s modulus in fatigue sites, and the
 other half were used to evaluate the validity of the pipeline in
 predicting PSG strain. The tuned model improved the prediction of strain
 and predicted higher strain in bones with PSG lysis over the untuned
 model, which is an essential feature for a diagnostic screening tool. The
 presented pipeline can assist clinicians with the interpretation of
 sCT-detectable structural changes and, ultimately, with the assessment of
 condylar fracture risk in racing Thoroughbreds. The standing
 computed tomography (sCT) images used in the linked manuscript can be
 found here. Specimens are labeled with unique IDs, which can be found in
 condyleID.txt. Essential DICOM tags are embedded in all of the image sets.
description: A library of 12 MC3 condyles (<em>n</em> = 12) from
 11 thoracic limb specimens, with available surface strain data under
 quasi-static loading of these condyles from previous <em>ex
 vivo</em> mechanical testing, was used for this study. Specimens
 were collected from Thoroughbred racehorses that were euthanized because
 of catastrophic racetrack injuries, including contralateral MC3 fractures
 through the PSG. Age, sex, and training history of the specimens were not
 available. These condyles included specimens with
 (<em>n</em> = 4, PSG-SBI group) and without
 (<em>n</em> = 8, CTRL group) sCT-detectable focal lysis in the
 PSG of the distal end of the MC3 bone. The existence of fatigue damage in
 the PSG of the specimens in the PSG-SBI group was previously confirmed
 following soft tissue dissection. The sCT scans of the frozen limbs were
 acquired using an Equina<sup>®</sup> scanner (Asto CT Inc.,
 Middleton, WI, USA) at exposure of 160 kVp and 8 mA, with a slice
 thickness of 0.55 mm.
description: # Data for: Tuning and validation of a virtual mechanical testing pipeline
 for condylar stress fracture risk assessment in Thoroughbred racehorses
 Dataset DOI: [10.5061/dryad.b5mkkwhqh](10.5061/dryad.b5mkkwhqh) ##
 Description of the data and file structure This dataset contains DICOM
 standing computed tomography (sCT) images of the thoracic limb(s) of 11
 Thoroughbred racehorses used in the study attached (Irandoust *et al.,*
 2025, *R Soc Open Sci*; **12**:
 241935*, *[https://doi.org/10.1098/rsos.241935](https://doi.org/10.1098/rsos.241935)). PSG-SBI specimens have focal osteolysis from fatigue damage in the palmar aspect of the parasagittal groove of the condyle (MC and LC, included in the specimenID.csv, stand for medial and lateral condyle, respectively) of the third metacarpal bone (LF stands for the left forelimb and RF stands for the right forelimb). CTRL specimens do not show this site-specific fatigue-induced structural change/damage. One specimen (CTRL8_PSG-SBI4_223LF) has one CTRL condyle and one PSG-SBI condyle. ### Files and variables #### File: CTRL1\_264RF.zip **Description:** contains standing computed tomography images of the specimen CTRL1 #### File: CTRL2\_141LF.zip **Description:** contains standing computed tomography images of the specimen CTRL2  #### File: CTRL3\_234LF.zip **Description:** contains standing computed tomography images of the specimen CTRL3 #### File: CTRL4\_163LF.zip **Description:** contains standing computed tomography images of the specimen CTRL4 #### File: CTRL5\_312LF.zip **Description:** contains standing computed tomography images of the specimen CTRL5 #### File: CTRL6\_292LF.zip **Description:** contains standing computed tomography images of the specimen CTRL6 #### File: CTRL7\_92LF.zip **Description:** contains standing computed tomography images of the specimen CTRL7 #### File: CTRL8\_PSG-SBI4\_223LF.zip **Description:** contains standing computed tomography images of the specimen CTRL8 and PSG-SBI4 #### File: PSG-SBI1\_21RF.zip **Description:** contains standing computed tomography images of the specimen PSG-SBI1 #### File: PSG-SBI2\_261LF.zip **Description:** contains standing computed tomography images of the specimen PSG-SBI2 #### File: PSG-SBI3\_243LF.zip **Description:** contains standing computed tomography images of the specimen PSG-SBI3 #### File: specimenID.csv **Description:** contains the specimen ID used in the research article attached (Irandoust et al., 2025 R Soc Open Sci) and the associated limb ID embedded in the sCT image sets, as well as the condyle IDs. ## Code/software Images can be viewed with any DICOM viewer.