FREE SHIPPING over $40
OVER 9000 FIVE-STAR REVIEWS
5% OFF ALL SUBSCRIPTIONS
100% HAPPINESS GUARANTEE
Analyze Diet
0
Home / Equine Research Bank / Equine Vet J / 2D-shear wave elastographic features of normal and injured e...
Equine veterinary journal2025; doi: 10.1111/evj.70091

2D-shear wave elastographic features of normal and injured equine superficial digital flexor tendons.

Abstract: Superficial digital flexor tendon (SDFT) injuries cause progressive loss of its mechanical properties. Two-dimensional shear wave elastography (2D-SWE) provides information about tissue stiffness. Objective: To determine the feasibility, repeatability, and reproducibility of 2D-SWE of healthy and pathological forelimb SDFT. Methods: Prospective observational cohort study. Methods: Horses were divided into a noninjured Group (H) and a Group with tendinopathy of the SDFT (P). 2D-SWE of both fore SDFTs was performed at three metacarpal levels (A, B, and C, from proximal to distal). Qualitative and quantitative assessments were performed by two operators, and interobserver agreement was calculated. Differences between Group H and P, and between the affected and unaffected limbs of Group P and with Group H were analysed. Statistical analysis was performed with SPSS IBM. Statistical significance was set for p < 0.05. Results: Thirty horses were enrolled (13 in Group H, 17 in Group P). Interobserver agreement was excellent to good. Qualitatively, in Group H, SDFT was from light to marked blue; in Group P, it appeared marked blue. Quantitatively, Group H had lower median mean shear wave velocity (SWV, m/s) and Young's modulus (kPa) at levels B and C (SWV: 8.19 and 8.27 m/s vs. 8.47 and 8.48 m/s; Young's modulus: 299.21 and 204 kPa vs. 216.03 and 214.44 kPa). In longitudinal scans, the unaffected limbs of Group P were different from the affected limb and from Group H at level B and in the transverse scan. The affected limbs of Group P were different from Group H in the transverse scan at levels B and C. Conclusions: Low sample size, examination of naturally occurring lesions, observational nature. Conclusions: 2D-SWE is feasible as a supplementary diagnostic method for detecting SDFT tendinopathies. Clinically healthy SDFTs exhibit lower SWV and Young's modulus values, suggesting less stiffness. Unassigned: Las lesiones de tendones flexores superficiales digitales (SDFT) causan una pérdida progresiva de las propiedades mecánicas de este. SWE en dos dimensiones (2D‐SWE) provee información sobre la rigidez tisular. Objective: determinar la factibilidad, repetibilidad y reproducibilidad de 2D‐SWE en SDFT extremidades anteriores sanos y patológicas. DISEÑO DEL ESTUDIO: estudio observacional de cohorte prospectivo. MÉTODOS: Caballos fueron divididos en grupo sano (H) y en grupo afectados por tendinopatía del SDFT (P). 2D‐SWE de ambos miembros anteriores fueron llevados a cabo en tres niveles metacarpianos (A, B, and C, de proximal a distal). Evaluaciones cualitativas y cuantitativas fueron llevadas a cabo por 2 operadores. Se calculo la concordancia inter observador. Se analizaron las diferencias entre los Grupos H y P, y entre los miembros afectados de P contra el miembro no afectado y con el Grupo H. El análisis estadístico fue llevado a cabo por SPSS IBM. La significancia estadística fue fijada en p < 0.05. Results: 30 caballos fueron enlistados (13 en Grupo H, 17 en Grupo P). La concordancia inter observador fue excelente a buena. Cualitativamente, en el Grupo H, SDFT variaba de azul claro a un azul fuerte, en el Grupo P, apareció azul fuerte. Cuantitativamente, el Grupo H tuvo una mediana m/s más baja y un Kpa en B y C (m/s: 8.19 y 8.27 vs 8.47 y 8.48; Kpa: 299.21 y 204 vs 216.03 y 214.44). En los escaners longitudinales, las extremidades no afectados de P siempre fueron diferentes de los miembros afectados y de los del Grupo H y en B y los escaners transversales. Las extremidades afectadas del Grupo P fueron diferentes a las del Grupo H en el escaner transversal en los niveles B y C. LIMITACIONES PRINCIPALES: tamaño de muestra pequeño, examen de lesiones ocurridas naturalmente, naturaleza observacional del estudio. Conclusions: 2D‐SWE se podría usar como método diagnóstico suplementario para detectar tendinopatías del SDFT. SDFT clínicamente sanos demuestran valores de m/s y kPa más bajos lo que sugiere que son menos rígidos.
© 2025 EVJ Ltd.
Get Full Text
Publication Date: 2025-09-05 PubMed ID: 40910344DOI: 10.1111/evj.70091Google 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.
LinkedInCopy
  • 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 evaluated the use of two-dimensional shear wave elastography (2D-SWE), a non-invasive ultrasound technique, to measure tissue stiffness in normal and injured superficial digital flexor tendons (SDFT) in horses.
  • The research demonstrated that 2D-SWE is a feasible, repeatable, and reproducible method for assessing tendon health and detecting tendinopathies by measuring differences in tendon stiffness.

Introduction and Background

  • The superficial digital flexor tendon (SDFT) is critical for equine forelimb function, and injuries to this tendon cause progressive loss of its mechanical properties, such as elasticity and strength.
  • Detecting changes in tendon stiffness can help identify tendinopathy (tendon disease) and monitor tendon health.
  • Two-dimensional shear wave elastography (2D-SWE) is an imaging modality that quantifies tissue stiffness by measuring shear wave velocity (SWV) and calculating Young’s modulus (a measure of elasticity) in kilopascals (kPa).
  • This method can provide both qualitative (color-coded images) and quantitative (numerical values) data about the mechanical properties of the tendon.

Objectives

  • To evaluate the feasibility, repeatability, and reproducibility of 2D-SWE in measuring stiffness of the forelimb SDFT in healthy horses and those with tendinopathies.
  • To compare the elastographic features between healthy tendons, affected tendons, and contralateral unaffected tendons in horses with injuries.

Methods

  • Study design: prospective observational cohort study involving 30 horses total.
  • Group division:
    • Group H: 13 horses with clinically healthy SDFT.
    • Group P: 17 horses diagnosed with SDFT tendinopathy.
  • Imaging protocol:
    • 2D-SWE performed on both forelimb SDFTs of each horse.
    • Three metacarpal levels (A, B, and C from proximal to distal) were scanned.
    • Qualitative assessment used color coding (blue shades) to visually represent tendon stiffness.
    • Quantitative assessment included measuring shear wave velocity (SWV in meters per second) and Young’s modulus (in kPa).
  • Two operators performed the imaging to assess interobserver agreement.
  • Statistical analysis compared Group H vs. Group P, affected vs. unaffected limbs within Group P, and unaffected limbs in Group P vs. Group H.
  • Significance threshold set at p < 0.05.

Results

  • Interobserver agreement ranged from good to excellent, indicating the technique’s reproducibility.
  • Qualitative observations:
    • Healthy tendons (Group H) appeared in shades from light blue to marked blue, indicating relatively lower stiffness.
    • Pathological tendons (Group P) consistently appeared marked blue, suggesting greater stiffness.
  • Quantitative measurements:
    • In healthy tendons, median SWV and Young’s modulus were lower at metacarpal levels B and C compared to pathological tendons.
    • For example, SWV for Group H was approximately 8.19 and 8.27 m/s at B and C versus 8.47 and 8.48 m/s in Group P.
    • Similarly, Young’s modulus was 299.21 and 204 kPa for Group H at B and C, versus 216.03 and 214.44 kPa for Group P (although note the Young’s modulus at B was slightly higher in Group H versus P, so this needs context in paper).
  • In longitudinal scans:
    • Unaffected limbs of horses in Group P differed significantly from both the affected limbs and horses in Group H at level B and in transverse scans, indicating potential subclinical changes or compensatory adaptations.
  • In transverse scans:
    • Affected limbs in Group P showed significant differences compared with Group H at levels B and C, supporting the sensitivity of 2D-SWE to detect injury-related changes.

Conclusions

  • 2D-SWE is a viable supplementary diagnostic tool for diagnosing SDFT tendinopathies in horses.
  • Clinically healthy tendons exhibit lower shear wave velocity and Young’s modulus values, indicating they are less stiff than injured tendons.
  • The technique demonstrated good reproducibility between operators.
  • The findings suggest that 2D-SWE can detect subtle changes in tendon stiffness both in obviously affected tendons and potentially in contralateral limbs.
  • Study limitations include small sample size, use of naturally occurring lesions instead of controlled injuries, and observational study design, which may limit generalizability.

Implications for Veterinary Practice

  • 2D-SWE can be integrated into clinical settings to improve detection and monitoring of tendon injuries in horses without invasive procedures.
  • Early detection through stiffness measurement may help to guide management and rehabilitation of affected tendons.
  • This technique may also be useful in research to better understand tendon healing and response to therapies.

Cite This Article

APA
Guerri G, Bandera L, Straticò P, Palozzo A, Di Nunzio L, Celani G, Varasano V, Vignoli M, Petrizzi L. (2025). 2D-shear wave elastographic features of normal and injured equine superficial digital flexor tendons. Equine Vet J. https://doi.org/10.1111/evj.70091

Publication

Equine veterinary journal
ISSN: 2042-3306
NlmUniqueID: 0173320
Country: United States
Language: English

Researcher Affiliations

Guerri, G
  • Department of Veterinary Medicine, University of Teramo, Teramo, Italy.
Bandera, L
  • Department of Veterinary Medicine, University of Teramo, Teramo, Italy.
Straticò, P
  • Department of Veterinary Medicine, University of Teramo, Teramo, Italy.
Palozzo, A
  • Equine Veterinary Medical Center, Education City, Qatar Foundation, Doha, Qatar.
Di Nunzio, L
  • Department of Veterinary Medicine, University of Teramo, Teramo, Italy.
Celani, G
  • Department of Veterinary Medicine, University of Teramo, Teramo, Italy.
Varasano, V
  • Department of Veterinary Medicine, University of Teramo, Teramo, Italy.
Vignoli, M
  • Department of Veterinary Medicine, University of Teramo, Teramo, Italy.
Petrizzi, L
  • Department of Veterinary Medicine, University of Teramo, Teramo, Italy.

Grant Funding

  • ECS00000041 / European Union -Next Generation EU
  • C43C22000380007 / European Union -Next Generation EU

References

This article includes 47 references
  1. Dowling BA, Dart AJ, Hodgson DR, Smith RKW. Superficial digital flexor tendonitis in the horse. Equine Vet J 2000;32:369–378.
  2. Alzola R, Easter C, Riggs CM, Gardner DS, Freeman SL. Ultrasonographic‐based predictive factors influencing successful return to racing after superficial digital flexor tendon injuries in flat racehorses: a retrospective cohort study in 469 thoroughbred racehorses in Hong Kong. Equine Vet J 2018;50:602–608.
  3. Goodship AE, Birch HL, Wilson AM. The pathobiology and repair of tendon and ligament injury. Vet Clin North Am Equine Pract 1994;10:323–349.
  4. Patterson‐Kane JC, Becker DL, Rich T. The pathogenesis of tendon microdamage in athletes: the horse as a natural model for basic cellular research. J Comp Pathol 2012;147:227–247.
  5. Patterson‐Kane JC, Firth EC. The pathobiology of exercise‐induced superficial digital flexor tendon injury in thoroughbred racehorses. Vet J 2009;181:79–89.
  6. O'Brien C, Marr N, Thorpe C. Microdamage in the equine superficial digital flexor tendon. Equine Vet J 2021;53:417–430.
  7. Berner D. Diagnostic imaging of tendinopathies of the superficial flexor tendon in horses. Vet Rec 2017;181:652–654.
  8. Davis LC, Baumer TG, Bey MJ, Van Holsbeeck M. Clinical utilization of shear wave elastography in the musculoskeletal system. Ultrasonography 2019;38:2–12.
  9. Drakonaki E, Allen GM, Wilson DJ. Ultrasound elastography for musculoskeletal applications. Br J Radiol 2012;85:1435–1445.
  10. Del Signore F, De Dominicis S, Mastromatteo G, Simeoni F, Scapolo PA, Tamburro R. Sonoelastography of normal canine common calcaneal tendon: preliminary results. Vet Comp Orthop Traumatol 2021;34:200–205.
  11. Straticò P, Guerri G, Palozzo A, Di Francesco P, Vignoli M, Varasano V. Elastosonographic features of the metacarpophalangeal joint capsule in horses. BMC Vet Res 2021;17:1–10.
  12. Lustgarten M, Redding WR, Labens R, Morgan M, Davis W, Seiler GS. Elastographic characteristics of the metacarpal tendons in horses without clinical evidence of tendon injury. Vet Radiol Ultrasound 2014;55:92–101.
  13. Tamura N, Kuroda T, Kotoyori Y, Fukuda K, Nukada T, Kato T. Application of sonoelastography for evaluating the stiffness of equine superficial digital flexor tendon during healing. Vet Rec 2017;180:120.
  14. Guerri G, Palozzo A, Straticò P, Varasano V, Celani G, Di Francesco P. 2D‐SWE of the metacarpophalangeal joint capsule in horses. Vet Sci 2022;9:478.
  15. Tamura N, Nukada T, Kato T, Kuroda T, Kotoyori Y, Fukuda K. The use of sonoelastography to assess the recovery of stiffness after equine superficial digital flexor tendon injuries: a preliminary prospective longitudinal study of the healing process. Equine Vet J 2017;49:590–595.
  16. Lustgarten M, Redding WR, Labens R, Davis W, Daniel TM, Griffith E. Elastographic evaluation of naturally occurring tendon and ligament injuries of the equine distal limb. Vet Radiol Ultrasound 2015;56:670–679.
  17. Secchi V, Masala G, Corda A, Corda F, Potop E, Fernandez AB. Strain elastography of injured equine superficial digital flexor tendons: a reliability study of manual measurements. Animals 2021;11:1–15.
  18. Johnson SA, Biscoe EW, Eilertson KE, Lutter JD, Schneider RK, Roberts GD. Tissue predictability of elastography is low in collagenase induced deep digital flexor tendinopathy. Vet Radiol Ultrasound 2022;63:111–123.
  19. Bernardi NS, Feliciano MAR, Gravena K, Avante ML, Simões APR, Uscategui RAR. Elastografia Acoustic Radiation Force Impulse (ARFI) das estruturas flexoras da porção distal do membro torácico de equinos. Arq Bras Med Vet Zootec 2020;72:1154–1162.
  20. Goddi A, Bonardi M, Alessi S. Breast elastography: a literature review. J Ultrasound 2012;15:192–198.
  21. Bassage LH II, Ross MW. Diagnostic analgesia. Diagnosis and Management of Lameness in the Horse Amsterdam: Elsevier; 2003. p. 93–124.
  22. Alzola Domingo R, Riggs CM, Gardner DS, Freeman SL. Ultrasonographic scoring system for superficial digital flexor tendon injuries in horses: intra‐and inter‐rater variability. Vet Rec 2017;181:655.
  23. Dirrichs T, Schrading S, Gatz M, Tingart M, Kuhl CK, Quack V. Shear wave elastography (SWE) of asymptomatic Achilles tendons: a comparison between semiprofessional athletes and the nonathletic general population. Acad Radiol 2019;26:1345–1351.
    doi: 10.1016/j.acra.2018.12.014google scholar: lookup
  24. Drakonaki EE, Allen GM, Wilson DJ. Real‐time ultrasound elastography of the normal Achilles tendon: reproducibility and pattern description. Clin Radiol 2009;64:1196–1202.
    doi: 10.1016/j.crad.2009.08.006google scholar: lookup
  25. Bouchet P, Gennisson J‐L, Podda A, Alilet M, Carrié M, Aubry S. Artifacts and technical restrictions in 2D shear wave elastography. Eur J Ultrasound 2020;41:267–277.
  26. Bamber J, Cosgrove D, Dietrich CF, Fromageau J, Bojunga J, Calliada F. EFSUMB guidelines and recommendations on the clinical use of ultrasound elastography. Part 1: basic principles and technology. Eur J Ultrasound 2013;34:169–184.
  27. Thorpe CT, Clegg PD, Birch HL. A review of tendon injury: why is the equine superficial digital flexor tendon most at risk?. Equine Vet J 2010;42:174–180.
  28. Rich T, Patterson‐Kane JC. Science‐in‐brief: what is needed to prevent tendon injury in equine athletes? A conversation between researchers and industry stakeholders. Equine Vet J 2014;46:393–398.
  29. Ehrle A, Lilge S, Clegg PD, Maddox TW. Equine flexor tendon imaging part 1: recent developments in ultrasonography, with focus on the superficial digital flexor tendon. Vet J 2021;278:105764.
    doi: 10.1016/j.tvjl.2021.105764google scholar: lookup
  30. Fulton IC, MacLean AA, O'Rielly JL, Church S. Superior check ligament desmotomy for treatment of superficial digital flexor tendonitis in thoroughbred and standardbred horses. Aust Vet J 1994;71:233–235.
  31. Kristoffersen M, Öhberg L, Johnston C, Alfredson H. Neovascularisation in chronic tendon injuries detected with colour Doppler ultrasound in horse and man: implications for research and treatment.. Knee Surg Sports Traumatol Arthrosc 2005;13:505–508.
  32. Boesen MI, Nanni S, Langberg H, Boesen M, Falk‐Ronne J, Bliddal H. Colour Doppler ultrasonography and sclerosing therapy in diagnosis and treatment of tendinopathy in horses—a research model for human medicine.. Knee Surg Sports Traumatol Arthrosc 2007;15:935–939.
  33. Murata D, Misumi K, Fujiki M. A preliminary study of diagnostic color Doppler ultrasonography in equine superficial digital flexor tendonitis.. J Vet Med Sci 2012;74:1639–1642.
  34. Rabba S, Grulke S, Verwilghen D, Evrard L, Busoni V. B‐mode and power Doppler ultrasonography of the equine suspensory ligament branches: a descriptive study on 13 horses.. Vet Radiol Ultrasound 2018;59:453–460.
  35. Lacitignola L, Rossella S, Crovace A. Power Doppler to investigate superficial digital flexor tendinopathy in the horse.. Open Vet J 2019;9:317–321.
  36. Rabba S, Petrucci V, Petrizzi L, Giommi DW, Busoni V. B‐mode ultrasonographic abnormalities and power Doppler signal in suspensory ligament branches of nonlame working quarter horses.. J Equine Vet Sci 2020;94:103254.
  37. Tamura N, Yoshihara E, Seki K, Mae N, Kodaira K, Iimori M. Prognostic value of power Doppler ultrasonography for equine superficial digital flexor tendon injury in thoroughbred racehorses.. Vet J 2024;306:106179.
  38. Boesen MI, Koenig MJ, Torp‐Pedersen S, Bliddal H, Langberg H. Tendinopathy and Doppler activity: the vascular response of the Achilles tendon to exercise.. Scand J Med Sci Sports 2006;16:463–469.
  39. Hatazoe T, Endo Y, Iwamoto Y, Korosue K, Kuroda T, Inoue S. A study of the distribution of color Doppler flows in the superficial digital flexor tendon of young thoroughbreds during their training periods.. J Equine Sci 2015;26:99–104.
  40. Risch L, Mayer F, Cassel M. Doppler flow response following running exercise differs between healthy and tendinopathic Achilles tendons.. Front Physiol 2021;12:650507.
  41. Bandera L, Guerri G, Straticò P, Pincelli MC, Celani G, Varasano V. Use of 2D‐shear wave elastography for the evaluation of lens in horses.. Vet Radiol Ultrasound 2025;66(3):e70052.
    doi: 10.1111/vru.70052google scholar: lookup
  42. Bernardi NS, da Cruz ICK, Maronezi MC, Santos MM, Lera KRJL, Gasser B. Applicability of ARFI elastography in detecting elasticity changes of the equine superficial digital flexor tendon with induced injury.. Vet Radiol Ultrasound 2022;63:790–797.
  43. Tamura N, Kodaira K, Yoshihara E, Mae N, Yamazaki Y, Mita H. A retrospective cohort study investigating risk factors for the failure of thoroughbred racehorses to return to racing after superficial digital flexor tendon injury.. Vet J 2018;235:42–46.
  44. Clegg PD, Strassburg S, Smith RK. Cell phenotypic variation in normal and damaged tendons.. Int J Exp Pathol 2007;88:227–235.
  45. Webbon PM. A post mortem study of equine digital flexor tendons.. Equine Vet J 1977;9:61–67.
  46. Agut A, Martínez ML, Sánchez‐Valverde MÁ, Soler M, Rodríguez MJ. Ultrasonographic characteristics (cross‐sectional area and relative echogenicity) of the digital flexor tendons and ligaments of the metacarpal region in purebred Spanish horses.. Vet J 2009;180:377–383.
  47. Ellison ME, Duenwald‐Kuehl S, Forrest LJ, Vanderby R, Brounts SH. Reproducibility and feasibility of acoustoelastography in the superficial digital flexor tendons of clinically normal horses.. Am J Vet Res 2014;75:581–587.

Citations

This article has been cited 0 times.
Subscribe to our newsletter
Join 99,002 horse owners like you who receive our email updates on horse health and nutrition.