FREE SHIPPING over $40
OVER 10000 FIVE-STAR REVIEWS
5% OFF ALL SUBSCRIPTIONS
100% HAPPINESS GUARANTEE
Analyze Diet
0
Veterinary surgery : VS2025; 55(3); 620-630; doi: 10.1111/vsu.70071

Comparative biomechanical analysis of equine accessory carpal bone fracture repair: Cortical screws in lag fashion versus X-plate technique.

Abstract: To compare the feasibility and biomechanical stability of two surgical techniques for fixation of vertical plane fractures of the accessory carpal bone (ACB). Methods: Randomized experimental ex vivo study. Methods: Eight equine accessory carpal bones were included in a control group. A total of 20 equine cadaveric forelimbs were randomly assigned into two groups (n = 10 per group). Methods: Vertical plane fractures were created palmar to the extensor sulcus using an oscillating saw. In Group 1 (CS), fractures were stabilized with two 4.5 mm cortical screws in lag fashion. In Group 2 (XP), fixation included one 4.5 mm cortical screw in lag fashion and a laterally applied angular stable X-plate with four 2.7 mm locking screws. Control ACBs were excised and tested under axial compression using a four-column testing machine. Postoperative specimens in Groups CS and XP were tested under the same conditions. The failure mode was assessed radiographically. Results: The mean maximum strength of native bone was 11.26 (±2.14) kN. Two constructs per group were excluded due to cortical screw protrusion. No difference in failure load was observed (CS: 6.82 [±2.34] kN; XP: 8.02 [±1.10] kN; p = .7558). Failure mode analysis revealed a greater fracture gap size (p = .0039) and implant bending in CS specimens (p = 1.074e-7). Conclusions: Both techniques were feasible, though neither restored native bone strength. Conclusions: A lateral X-plate with a single cortical screw demonstrated equivalent biomechanical performance to two cortical screws and was technically less demanding, offering a simpler fixation option for ACB fractures.
© 2025 The Author(s). Veterinary Surgery published by Wiley Periodicals LLC on behalf of American College of Veterinary Surgeons.
Get Full Text
Publication Date: 2025-12-21 PubMed ID: 41423917DOI: 10.1111/vsu.70071Google 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
  • Comparative Study

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 compares two surgical methods for repairing vertical fractures in the equine accessory carpal bone (ACB) using biomechanical testing on cadaver limbs.
  • The goal was to evaluate which fixation technique provides better stability and is more feasible for clinical use.

Background and Purpose

  • The accessory carpal bone is a small bone in a horse’s carpus (wrist region) prone to vertical fractures.
  • Treating these fractures requires stable fixation to allow proper healing and restore function.
  • This study aims to compare:
    • Using two 4.5 mm cortical screws applied in a lag fashion (Group CS).
    • Using a combination of one 4.5 mm cortical screw in lag fashion plus a lateral angular stable X-plate with four 2.7 mm locking screws (Group XP).

Methods

  • A total of 28 equine accessory carpal bones (from cadaver forelimbs) were used:
    • 8 intact bones in a control group with no fractures, tested for baseline biomechanical strength.
    • 20 limbs randomly assigned into two experimental groups of 10 each (Group CS and Group XP).
  • Vertical fractures were artificially created using an oscillating saw on the palmar side of the ACB.
  • Fractures were fixed according to group assignment:
    • Group CS: two cortical screws placed in lag fashion.
    • Group XP: one cortical screw in lag fashion plus the X-plate laterally applied with four locking screws.
  • Specimens were tested under axial compression loading mimicking forces the bone would experience physiologically.
  • The failure mode was assessed radiographically to understand how and where failure occurred.

Results

  • The maximum strength of intact (native) ACBs averaged 11.26 kN ± 2.14.
  • Two specimens from each experimental group were excluded due to improper screw placement (protrusion).
  • No statistically significant difference was found in failure load between the two fixation techniques:
    • CS group: 6.82 kN ± 2.34
    • XP group: 8.02 kN ± 1.10
    • p-value = 0.7558, indicating similar mechanical strength.
  • Failure mode differences:
    • CS group showed significantly greater fracture gap size post-failure (p = 0.0039), suggesting more displacement.
    • CS specimens exhibited more implant bending (p ≈ 1.07e-7), indicating less rigid fixation.

Conclusions and Clinical Relevance

  • Both fixation techniques were technically feasible for ACB fracture repair.
  • Neither technique fully restored the original strength of the native bone under testing conditions.
  • The lateral X-plate combined with a single cortical screw provided biomechanical performance equivalent to two cortical screws, but with less implant bending and smaller fracture gap.
  • The X-plate method was less technically demanding and simpler to apply, which may translate into clinical ease and reliability.
  • These findings support the lateral X-plate technique as a viable alternative for repairing vertical plane ACB fractures in horses.

Cite This Article

APA
Gernhardt J, Reuter T, Mählmann K, Schulze N, Lischer CJ. (2025). Comparative biomechanical analysis of equine accessory carpal bone fracture repair: Cortical screws in lag fashion versus X-plate technique. Vet Surg, 55(3), 620-630. https://doi.org/10.1111/vsu.70071

Publication

Veterinary surgery : VS
ISSN: 1532-950X
NlmUniqueID: 8113214
Country: United States
Language: English
Volume: 55
Issue: 3
Pages: 620-630

Researcher Affiliations

Gernhardt, Jennifer
  • Equine Clinic, Freie Universität Berlin, Berlin, Germany.
Reuter, Thomas
  • ICM-Institut Chemnitzer Maschinen- und Anlagenbau e.V, Chemnitz, Germany.
Mählmann, Kathrin
  • Equine Clinic, Freie Universität Berlin, Berlin, Germany.
Schulze, Nicole
  • Equine Clinic, Freie Universität Berlin, Berlin, Germany.
Lischer, Christoph J
  • Equine Clinic, Freie Universität Berlin, Berlin, Germany.

MeSH Terms

  • Animals
  • Horses / injuries
  • Horses / surgery
  • Bone Screws / veterinary
  • Biomechanical Phenomena
  • Fractures, Bone / surgery
  • Fractures, Bone / veterinary
  • Fracture Fixation, Internal / veterinary
  • Fracture Fixation, Internal / methods
  • Fracture Fixation, Internal / instrumentation
  • Bone Plates / veterinary
  • Cadaver
  • Carpal Bones / surgery
  • Carpal Bones / injuries

Grant Funding

  • DePuy Synthes

References

This article includes 36 references
  1. Rijkenhuizen AB, Nemeth F. Accessory carpal bone fractures in the horse. Vet Q 1994;16:101‐103.
  2. Auer J. Diseases of the carpus. Vet Clin North Am Large Anim Pract 1980;2:81‐99.
  3. Barr AR, Sinnott MJ, Denny HR. Fractures of the accessory carpal bone in the horse. Vet Rec 1990;126:432‐434.
  4. Easley KJ. The accessory carpal bone. In: Mansmann RA, McAllister ES, Pratt PW, eds. Equine Medicine and Surgery. 3rd ed. American Veterinary Publications; 1982:1126‐1131.
  5. Wyn‐Jones G. Conditions of the upper forelimb. In: Wyn‐Jones G, ed. Equine lameness. Blackwell Scientific Publications; 1988:112‐115.
  6. Carson DM. The osseous repair of a horizontal fracture of the accessory carpal bone in a thoroughbred racehorse. Equine Vet Educ 1990;2:173‐176.
  7. Roberts EJ. Carpal Lameness. Equine Veterinary Journal 1964:18‐28.
  8. Ruggles AJ. Carpus. In: Auer J, Stick A, Kümmerle J, et al., eds. Equine Surgery. 5th ed. Elsevier Inc; 2019:1658‐1660.
  9. Minshall GJ, Wright IM. Frontal plane fractures of the accessory carpal bone and implications for the carpal sheath of the digital flexor tendons. Equine Vet J 2014;46:579‐584.
  10. Ross MW. The carpus. In: Ross MW, Dyson SJ, eds. Diagnosis and Management of Lameness in the Horse. Elsevier Inc; 2011:446.
  11. McIlwraith CW. Accessory carpal bone fractures. In: Nixon AJ, ed. Equine Fracture Repair. Wiley‐Blackwell; 2020:510‐512.
  12. Boyce T, Edwards J, Scarborough N. Allograft bone. The influence of processing on safety and performance. Orthop Clin North Am 1999;30:571‐581.
  13. Burchardt H, Jones H, Glowczewskie F, Rudner C, Enneking WF. Freeze‐dried allogeneic segmental cortical‐bone grafts in dogs. J Bone Joint Surg Am 1978;60:1082‐1090.
  14. Erhart J, Unger E, Schefzig P. Rotational stability of scaphoid Osteosyntheses: an in vitro comparison of small fragment cannulated screws to novel bone screw sets. PLoS One 2016;11:1‐17.
  15. De Preux M, Van der Vekens E, Racine J. Accessory carpal bone fracture repair by means of computer‐assisted orthopaedic surgery in a warmblood stallion. Equine Vet Educ 2022;34:478‐484.
  16. Aßmann AD, Fürst AE, Bischofberger AS. Standing osteosynthesis of an accessory carpal bone fracture in a warmblood mare with a 6‐hole 3.5 talonavicular fusion plate and 3.5‐mm screws.. Equine Vet Educ 2023;35:398‐405.
  17. Launois T, Vandekeybus L, Desbrosse F. Accessory Carpal Bone Fixation in Cases of Simple Frontal Fracture, using the dorso 80° proximo 30° lateral ‐ palmarodistomedial (Skyline) View. Proceedings of the European College of Veterinary Surgeons, 10th Annual Scientific Meeting Velbert, Germany, 2001; 35–37.
  18. Synthes GmbH. Instructions for Use Plate and Screw Implants. 2019.
  19. Campos A, Rossignol F. 3D printed 3.5mm LCP titanium plate for accessory carpal bone fracture repair in horses. Veterinary and Comparative Orthopaedics and Traumatology 2023:1‐27.
  20. Launois T, Vandekeybus L, Desbrosse F, Perrin R. Dorsal 80° proximal 30° lateral‐palmarodistal medial oblique view for screw fixation of the accessory carpal bone. J Equine Vet Sci 2002;22:265‐271.
  21. Dunn OJ. Multiple comparisons using rank sums. Technometrics 1964;2:241‐252.
  22. Landis JR, Koch GG. The measurement of observer agreement for categorical data. Biometrics 1977;33:159‐174.
  23. Fox J, Weisberg S. An R Companion to Applied Regression. Sage; 2019.
  24. Revelle W. psych: Procedures for Psychological, Psychometric, and Personality Research. R package 2.5.6. Northwestern University; 2025.
  25. Kassambara A. rstatix: Pipe‐Friendly Framework for Basic Statistical Tests. R package version 0.7.2. 2023.
  26. Signorell A. DescTools: Tools for Descriptive Statistics. R package version 0.99.60 ed. 2024.
  27. Wickham H. Welcome to the tidyverse. J Open Source Softw 2019;4:1686.
  28. Ben‐Shachar MS, Lüdecke D, Makowski D. Effectsize: estimation of effect size indices and standardized parameters. J Open Source Softw 2020;5:2815.
  29. Cohen J. A power primer. Psychol Bull 1992;112:155‐159.
  30. De Preux M, Klopfenstein Bregger MD, Brünisholz HP, der Van Vekens E, Schweizer‐Gorgas D, Koch C. Clinical use of computer‐assisted orthopedic surgery in horses. Vet Surg 2020;49:1075‐1087.
  31. De Preux M, Vidondo B, Koch C. Influence of a purpose‐built frame on the accuracy of computer‐assisted orthopedic surgery of equine extremities.. Vet Surg 2020;49:1367‐1377.
  32. Munroe GA, Cauvin E. Surgical treatment of a comminuted articular fracture of the accessory carpal bone in a thoroughbred horse.. Vet Rec 1997;141:47‐49.
  33. Wilke M, Nixon AJ, Malark J, Myhre G. Fractures of the palmar aspect of the carpal bones in horses: 10 cases (1984‐2000).. J Am Vet Med Assoc 2001;219:801‐804.
  34. Personal communication of Lischer, Christoph with Denoix, Jean‐Marie. 2019.
  35. Reuter T, Gernhardt J, Rutter C. 3‐D modeling of stresses and strains in accessory carpal bone under maximum compressive loading.. Paper presented at: COMSOL Conference. Munich, 2023.
  36. Reuter T, Gernhardt J, Rutter C. Biomechanical characterization of accessory carpal bone by force‐to‐failure experiments.. 29th Congress of the European Society of Biomechanics. European Society of Biomechanics; 2024.

Citations

This article has been cited 0 times.
Subscribe to our newsletter
Join 100,191 horse owners like you who receive our email updates on horse health and nutrition.