Analyze Diet
Scientific reports2025; 16(1); 1166; doi: 10.1038/s41598-025-30921-6

Standing CT-based finite element models efficiently identify regions of high mechanical strain in equine metacarpal subchondral bone.

Abstract: Stress fractures are common in racehorses, with the metacarpophalangeal (MCP) joint being the most frequently affected site as it is subjected to high-magnitude and high-rate cyclic loads during training and racing. These loads lead to repeated compressive stresses, resulting in subchondral bone (SCB) sclerosis, fatigue microcracks, and matrix damage that can progress to parasagittal fractures or palmar osteochondral disease (POD). The present study developed joint-specific 3D FE models and slice-based FE models using standing CT images for three trained racehorses, each presenting distinct SCB conditions common in racehorses as identified by their CT images: (1) biaxial sclerotic condylar SCB with no visible lesions: BS, (2) focal lytic SCB with associated sclerosis in the PSG: LGL, and (3) focal lytic SCB with associated sclerosis in the condyles: BCL. Both models predicted similar overall patterns of SCB stress and strain, identifying peak tensile and compressive strains in the PSGs and condyles, while minimal strains were observed over the sagittal ridge. The 3D models predicted a larger volume of highly strained bone compared to slice-based models, particularly in the horse with biaxial sclerosis. Both 3D and slice-based FE models demonstrated strong agreement in identifying the PSG and midcondyles as high-strain regions. The sensitivity analysis showed that variations in input parameters had minimal impact on the results, indicating the robustness of slice-based models. Despite being less detailed, slice-based models were much faster and more straightforward to develop and provided stress and strain patterns comparable to 3D models. These findings suggest that slice-based models offer a valuable tool for rapid assessment of biomechanical behaviour in equine fetlock joints, particularly for identifying regions at high-risk of failure in the clinical setting.
Publication Date: 2025-12-11 PubMed ID: 41381693PubMed Central: PMC12789503DOI: 10.1038/s41598-025-30921-6Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
  • Journal Article

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

Overview

  • This study developed and compared 3D and slice-based finite element (FE) models from standing CT images to identify areas of high mechanical strain in the subchondral bone of equine metacarpal joints.
  • The goal was to determine if quicker, less complex slice-based models could effectively detect high-strain regions linked to stress fractures and bone damage in racehorses, which experience heavy joint loading.

Background and Rationale

  • Racehorses often suffer stress fractures, particularly in the metacarpophalangeal (MCP) joint, due to repetitive large and rapid loads during training and racing.
  • The MCP joint is vulnerable because the high-magnitude cyclic loading causes compressive stresses in the subchondral bone (SCB), leading to sclerosis (hardening), microcracks, and eventually larger bone lesions or fractures.
  • Understanding which regions within the SCB are subjected to high strain is important for predicting injury risk and managing equine athlete health.
  • Finite element (FE) modeling is a computational technique that can estimate internal bone stresses and strains from imaging data, helping identify these high-risk regions.
  • Traditional 3D FE models are detailed but time-consuming to build and analyze, while slice-based FE models simplify the structure into sectional slices, which is faster and easier.

Study Design and Methods

  • The researchers used standing CT scans of the MCP joints from three trained racehorses, each displaying different SCB pathologies commonly seen in racehorses:
    • Horse 1: Biaxial sclerotic condylar SCB without visible lesions (BS).
    • Horse 2: Focal lytic SCB with associated sclerosis in the parasagittal groove (PSG) (LGL).
    • Horse 3: Focal lytic SCB with associated sclerosis in the condyles (BCL).
  • They developed two types of FE models from the CT images for each horse:
    • Joint-specific full 3D FE models capturing the detailed geometry of the MCP joint.
    • Slice-based FE models focusing on sectional slices through the bone.
  • The models estimated patterns of stress and strain within the SCB under loading conditions representative of the standing joint.
  • A sensitivity analysis tested the influence of variations in input parameters on model results to assess robustness.

Key Findings

  • Both 3D and slice-based models predicted similar overall spatial patterns of stress and strain:
    • Peak tensile and compressive strains were consistently located in the parasagittal grooves (PSGs) and condyles.
    • The sagittal ridge showed minimal strains in all models and cases.
  • The 3D models predicted a greater volume of highly strained bone, especially in the horse with biaxial sclerosis, indicating more detailed stress distribution representation.
  • Strong agreement existed between the two modeling approaches in pinpointing the PSG and midcondyles as regions of high mechanical strain, which are clinically relevant locations for stress fracture development.
  • The sensitivity analysis demonstrated that reasonable variations in input parameters minimally affected strain predictions, indicating that slice-based models are robust despite their simplifications.
  • Slice-based FE models were much faster and easier to develop compared to full 3D models, yet provided comparable stress-strain pattern insights relevant for clinical evaluation.

Implications and Conclusion

  • Slice-based FE models from standing CT scans offer a practical and efficient tool for rapid biomechanical assessment of equine MCP joints, helping identify regions at high risk of failure.
  • This approach could support clinicians in monitoring racehorses for early signs of stress-related bone damage, potentially allowing for quicker intervention to prevent severe fractures.
  • While 3D FE models provide more detailed volumetric information, slice-based models balance accuracy and resource demands, making them suitable for clinical settings where speed and simplicity are valuable.
  • Future work might refine slice-based models further or integrate both modeling strategies to optimize diagnosis and treatment planning in equine sports medicine.

Cite This Article

APA
Malekipour F, Whitton RC, Muir P, Lee PV. (2025). Standing CT-based finite element models efficiently identify regions of high mechanical strain in equine metacarpal subchondral bone. Sci Rep, 16(1), 1166. https://doi.org/10.1038/s41598-025-30921-6

Publication

ISSN: 2045-2322
NlmUniqueID: 101563288
Country: England
Language: English
Volume: 16
Issue: 1
Pages: 1166
PII: 1166

Researcher Affiliations

Malekipour, Fatemeh
  • Department of Biomedical Engineering, University of Melbourne, Parkville, VIC, 3010, Australia.
Whitton, R Chris
  • Equine Centre, Faculty of Veterinary and Agricultural Sciences, University of Melbourne, Werribee, VIC, 3030, Australia.
Muir, Peter
  • Department of Surgical Sciences, School of Veterinary Medicine, University of Wisconsin-Madison, Madison, USA.
Lee, Peter Vee-Sin
  • Department of Biomedical Engineering, University of Melbourne, Parkville, VIC, 3010, Australia. pvlee@unimelb.edu.au.

MeSH Terms

  • Horses
  • Animals
  • Metacarpal Bones / diagnostic imaging
  • Finite Element Analysis
  • Stress, Mechanical
  • Tomography, X-Ray Computed / methods
  • Metacarpophalangeal Joint / diagnostic imaging
  • Biomechanical Phenomena
  • Fractures, Stress / diagnostic imaging
  • Fractures, Stress / veterinary
  • Horse Diseases / diagnostic imaging

Conflict of Interest Statement

Declarations. Competing interests: Peter Muir is a Founder of Asto CT, a subsidiary of Centaur Health Holdings Inc. and the founder of Eclipse Consulting LLC.

References

This article includes 40 references
  1. Harrison SM, Whitton RC, Kawcak CE, Stover SM, Pandy MG. Evaluation of a subject-specific finite-element model of the equine metacarpophalangeal joint under physiological load. 65–73 (2014).
  2. Bani Hassan E, Mirams M, Mackie EJ, Whitton RC. Prevalence of subchondral bone pathological changes in the distal metacarpi/metatarsi of racing thoroughbred horses. 362–369 (2017).
    doi: 10.1111/avj.12628pubmed: 28948629google scholar: lookup
  3. Pinchbeck GL, Clegg PD, Boyde A, Riggs CM. Pathological and clinical features associated with palmar/plantar osteochondral disease of the metacarpo/metatarsophalangeal joint in thoroughbred racehorses. 587–592 (2013).
    doi: 10.1111/evj.12036pubmed: 23418959google scholar: lookup
  4. Whitton RC, Ayodele BA, Hitchens PL, Mackie EJ. Subchondral bone microdamage accumulation in distal metacarpus of thoroughbred racehorses. 766–773 (2018).
    doi: 10.1111/evj.12948pubmed: 29660153google scholar: lookup
  5. Barr ED, Pinchbeck GL, Clegg PD, Boyde A, Riggs CM. Post mortem evaluation of palmar osteochondral disease (traumatic osteochondrosis) of the metacarpo/metatarsophalangeal joint in thoroughbred racehorses. 366–371 (2009).
    doi: 10.2746/042516409X368372pubmed: 19562898google scholar: lookup
  6. Parkin TDH. Catastrophic fracture of the lateral condyle of the third metacarpus/metatarsus in UK racehorses - Fracture descriptions and pre-existing pathology. 157–165 (2006).
    doi: 10.1016/j.tvjl.2004.10.009pubmed: 16427592google scholar: lookup
  7. Brounts SH. Use of a novel helical fan beam imaging system for computed tomography of the distal limb in sedated standing horses: 167 cases (2019–2020). 1351–1360 (2022).
    doi: 10.2460/javma.21.10.0471pubmed: 35943949google scholar: lookup
  8. Bani Hassan E, Mirams M, Ghasem-Zadeh A, Mackie EJ, Whitton RC. Role of subchondral bone remodelling in collapse of the articular surface of thoroughbred racehorses with palmar osteochondral disease. 228–233 (2016).
    doi: 10.1111/evj.12415pubmed: 25582246google scholar: lookup
  9. Colgate VA, Riggs CM. IFHA global summit of equine safety and technology: fracture prediction and prevention. (5) (2025).
    doi: 10.1111/evj.14458google scholar: lookup
  10. Dubois MS. Computed tomographic imaging of subchondral fatigue cracks in the distal end of the third metacarpal bone in the thoroughbred racehorse can predict crack micromotion in an ex-vivo model. 9 (2014).
  11. Malekipour F, Oetomo D, Lee PVS. Equine subchondral bone failure threshold under impact compression applied through articular cartilage. 1–7 (2016).
  12. Malekipour F, Whitton RC, Lee PVS. Distribution of mechanical strain in equine distal metacarpal subchondral bone: A microCT-based finite element model. 100036 (2020).
  13. McCarty CA. Finite-element analysis of bone stresses on primary impact in a large-animal model: the distal end of the equine third metacarpal. 1–22 (2016).
  14. Jiang H, Robinson DL, Yates CJ, Lee PVS, Wark JD. Peripheral quantitative computed tomography (pQCT)–based finite element analysis provides enhanced diagnostic performance in identifying non-vertebral fracture patients compared with dual-energy X-ray absorptiometry. 141–151 (2020).
    doi: 10.1007/s00198-019-05213-1pubmed: 31720708google scholar: lookup
  15. Robinson DL. The application of finite element modelling based on clinical pQCT for classification of fracture status. 245–260 (2019).
    doi: 10.1007/s10237-018-1079-7pubmed: 30293203google scholar: lookup
  16. Malekipour F, Lee PVS, CW. Compressive stiffness of the third metacarpal subchondral bone in thoroughbred racehorses: a combined experimental and finite element study. Aust. New Zeal. Orthop. Res. Soc. Melbourne, Aust. 2016.
  17. Malekipour F, Whitton CR, Lee PVS. Stiffness and energy dissipation across the superficial and deeper third metacarpal subchondral bone in thoroughbred racehorses under high-rate compression. 51–56 (2018).
    doi: 10.1016/j.jmbbm.2018.05.031pubmed: 29852352google scholar: lookup
  18. Shaktivesh Malekipour, F. & CWLPVS. (Int. Soc. Biomech. Calgary, 2019).
    pubmed: 31403713
  19. Martig S, Lee PVS, Anderson G, Whitton RC. Compressive fatigue life of subchondral bone of the metacarpal condyle in thoroughbred racehorses. 392–398 (2013).
    doi: 10.1016/j.bone.2013.09.006pubmed: 24063945google scholar: lookup
  20. Shaffer SK, Sachs N, Garcia TC, Fyhrie DP, Stover SM. In vitro assessment of the motion of equine proximal sesamoid bones relative to the third metacarpal bone under physiologic Midstance loads. 198–206 (2021).
    doi: 10.2460/ajvr.82.3.198pubmed: 33629903google scholar: lookup
  21. Wirtz DC et al. Critical evaluation of known bone material properties to realize anisotropic FE-simulation of the proximal femur. 1325–1330 (2000).
    doi: 10.1016/S0021-9290(00)00069-5pubmed: 10899344google scholar: lookup
  22. Ateshian G, Ellis BJ, Weiss JA. Equivalence between short-time biphasic and incompressible elastic material responses. 405–12 (2007).
    pmc: PMC3312381pubmed: 17536908doi: 10.1115/1.2720918google scholar: lookup
  23. Chegini S, Ferguson SJ. Time and depth dependent poisson’s ratio of cartilage explained by an inhomogeneous orthotropic fiber embedded biphasic model. 1660–1666 (2010).
  24. Canal CE et al. Optical measurement of in situ strain fields within osteochondral tissue under indentation. 2–3 (2002).
  25. Korhonen RK et al. Comparison of the equilibrium response of articular cartilage in unconfined compression, confined compression and indentation. 903–909 (2002).
    doi: 10.1016/S0021-9290(02)00052-0pubmed: 12052392google scholar: lookup
  26. Wilson W, van Donkelaar CC, van Rietbergen B, Huiskes R. A fibril-reinforced poroviscoelastic swelling model for articular cartilage. 1195–1204 (2005).
  27. Julkunen P et al. Stress-relaxation of human patellar articular cartilage in unconfined compression: prediction of mechanical response by tissue composition and structure. 1978–1986 (2008).
  28. Segal NA et al. Baseline articular contact stress levels predict incident symptomatic knee osteoarthritis development in the MOST cohort. 1562–1568 (2009).
    doi: 10.1002/jor.20936pmc: PMC2981407pubmed: 19533741google scholar: lookup
  29. Easton KL. Effect of bone geometry on stress distribution patterns in the equine metacarpophalangeal joint. 99 (2012).
  30. Brama PAJ, Karssenberg D, Barneveld A, Van Weeren PR. Contact areas and pressure distribution on the proximal articular surface of the proximal phalanx under sagittal plane loading. 26–32 (2001).
    doi: 10.2746/042516401776767377pubmed: 11191606google scholar: lookup
  31. Irandoust S, Whitton RC, Muir P, Henak CR. Subchondral bone fatigue injury in the parasagittal condylar grooves of the distal end of the third metacarpal bone in thoroughbred racehorses elevates Site-Specific strain concentration. 106561 (2023).
    doi: 10.1016/j.jmbbm.2024.106561pubmed: 38678748google scholar: lookup
  32. Duboust N et al. 2D and 3D finite element models for the edge trimming of CFRP. 233–238 (2017).
  33. Romeed SA, Fok SL, Wilson NHF. A comparison of 2D and 3D finite element analysis of a restored tooth. 209–215 (2006).
  34. Malekipour F, Hitchens PL, Whitton RC, Vee-Sin Lee P. Effects of in vivo fatigue-induced microdamage on local subchondral bone strains. 105491 (2022).
    doi: 10.1016/j.jmbbm.2022.105491pubmed: 36198232google scholar: lookup
  35. Malekipour F, Whitton CR, Lee PVS. Stiffness and energy dissipation across the superficial and deeper third metacarpal subchondral bone in thoroughbred racehorses under high-rate compression. 51–56 (2018).
    doi: 10.1016/j.jmbbm.2018.05.031pubmed: 29852352google scholar: lookup
  36. Wang D, Akbari A, Jiang F, Liu Y, Chen J. The effects of different types of periodontal ligament material models on stresses computed using finite element models. e328–e336 (2022).
    doi: 10.1016/j.ajodo.2022.09.008pmc: PMC9722581pubmed: 36307342google scholar: lookup
  37. Bi S, Shi G. The crucial role of periodontal ligament’s poisson’s ratio and tension-compression asymmetric moduli on the evaluation of tooth displacement and stress state of periodontal ligament. 106217 (2023).
    doi: 10.1016/j.jmbbm.2023.106217pubmed: 37931551google scholar: lookup
  38. Ayobami OO, Goldring SR, Goldring MB, Wright TM, van der Meulen MCH. Contribution of joint tissue properties to load-induced osteoarthritis. 101602 (2022).
    doi: 10.1016/j.bonr.2022.101602pmc: PMC9309407pubmed: 35899096google scholar: lookup
  39. Hayes A, Clift SE, Miles AW. An investigation of the stress distribution generated in articular cartilage by crystal aggregates of varying material properties. 242–252 (1997).
    doi: 10.1016/S1350-4533(96)00072-0pubmed: 9239643google scholar: lookup
  40. Malekipour F, Hitchens PL, Whitton RC, Lee PVS. Effects of in vivo fatigue-induced subchondral bone microdamage on the mechanical response of cartilage-bone under a single impact compression. 109594 (2020).

Citations

This article has been cited 0 times.