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Scientific reports2019; 9(1); 9978; doi: 10.1038/s41598-019-46444-w

Evaluation of the Structure of Myodural Bridges in an Equine Model of Ehlers-Danlos Syndromes.

Abstract: Myodural bridges have been described in various species as connective tissue structures "bridging" small cranio-cervical muscles to the dura. Myodural bridges are thought to stabilize the dural sac during head and neck movements and promote cerebrospinal fluid motion; however, their role in neurological diseases has not yet been established. We report ultrasonographic visualization, necropsy, histopathologic and ultrastructural findings of myodural bridges in horses with hereditary equine regional dermal asthenia (HERDA), an equine model of Ehlers-Danlos syndromes. Five HERDA and 5 control horses were studied. Post-mortem examination and ultrasonographic studies (3 HERDA and 4 controls) demonstrated that the atlanto-occipital and atlanto-axial myodural bridges are dynamic structures "moving" the dura. En block resection of the myodural bridges (4 HERDA and 5 controls) was accomplished and histopathology showed myofiber degeneration in 3 HERDA horses and 1 control. Ultrastructural examination revealed loosely packed collagen fibrils with abnormal orientation in all HERDA horses compared to mild abnormalities in 2 controls. Our study provides necropsy and ultrasonographic evidence of the dynamic aspect of the myodural bridges as dural sac stabilizers. Myodural bridges may be pathologically altered in connective tissue disease as evidenced by the ultrastructural morphology in the HERDA myodural bridge.
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Publication Date: 2019-07-10 PubMed ID: 31292490PubMed Central: PMC6620297DOI: 10.1038/s41598-019-46444-wGoogle Scholar: Lookup
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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.

The study explores the role and structure of myodural bridges (connective tissues in the neck) in relation to Ehlers-Danlos syndromes, a group of disorders affecting connective tissues. Through observation and examination of horses with hereditary equine regional dermal asthenia (HERDA), an equine model of Ehlers-Danlos syndromes, this research sheds light on potential impacts of altered myodural bridges in connective tissue diseases.

Understanding Myodural Bridges

  • The researchers in this study sought to investigate myodural bridges, connective tissue structures found in various species. These “bridges” are tied between small cranio-cervical muscles and the dura, a layer surrounding the brain and spinal cord.
  • The primary function of these myodural bridges is to maintain stability in the dural sac during neck and head movements, and to facilitate cerebrospinal fluid movement.
  • The role of these structures in neurological diseases still remains largely unexplored.

Methodology and Findings

  • HERDA (hereditary equine regional dermal asthenia) horses, an equine equivalent of Ehlers-Danlos syndromes, were the focus of this study, with a total of five HERDA horses and five control horses being examined.
  • Both post-mortem examination and ultrasonographic studies indicate that the myodural bridges found at the atlanto-occipital and atlanto-axial regions are dynamic structures that contribute to movement of the dura.
  • After resection of the myodural bridges, histopathology showed signs of muscle fiber degeneration in three of the HERDA horses and one control horse.
  • On a more intricate level, ultrastructural examination revealed abnormalities in the arrangement of the collagen fibrils in the HERDA horses, as compared to only minor abnormalities observed in two of the control horses.

Conclusion

  • This study provides proof via necropsy and ultrasonography of the dynamic role myodural bridges play in dural sac stability.
  • The researchers suggest that myodural bridges could be pathologically altered in connective tissue diseases, as indicated by the abnormal collagen configuration found in the myodural bridges of the HERDA horses.
  • While this research is a step in the right direction, more extensive study is needed to identify the full role of myodural bridges in the pathology of neurological and connective tissue diseases.

Cite This Article

APA
McElroy A, Rashmir A, Manfredi J, Sledge D, Carr E, Stopa E, Klinge P. (2019). Evaluation of the Structure of Myodural Bridges in an Equine Model of Ehlers-Danlos Syndromes. Sci Rep, 9(1), 9978. https://doi.org/10.1038/s41598-019-46444-w

Publication

Scientific reports
ISSN: 2045-2322
NlmUniqueID: 101563288
Country: England
Language: English
Volume: 9
Issue: 1
Pages: 9978

Researcher Affiliations

McElroy, Abigail
  • Michigan State University College of Veterinary Medicine, Large Animal Clinical Sciences, East Lansing, MI, USA. amce1991@gmail.com.
Rashmir, Ann
  • Michigan State University College of Veterinary Medicine, Large Animal Clinical Sciences, East Lansing, MI, USA.
Manfredi, Jane
  • Michigan State University College of Veterinary Medicine, Pathobiology and Diagnostic Investigation, East Lansing, MI, USA.
Sledge, Dodd
  • Michigan State University Veterinary Diagnostic Laboratory, Lansing, MI, USA.
Carr, Elizabeth
  • Michigan State University College of Veterinary Medicine, Large Animal Clinical Sciences, East Lansing, MI, USA.
Stopa, Edward
  • Rhode Island Hospital, Departments of Pathology and Neurosurgery, Providence, RI, USA.
Klinge, Petra
  • Rhode Island Hospital, Department of Neurosurgery, Providence, RI, USA.

MeSH Terms

  • Animals
  • Cervical Vertebrae / pathology
  • Connective Tissue / pathology
  • Connective Tissue / ultrastructure
  • Dura Mater / pathology
  • Ehlers-Danlos Syndrome / pathology
  • Ehlers-Danlos Syndrome / veterinary
  • Horse Diseases / pathology
  • Horses
  • Neck / pathology
  • Neck Muscles / pathology
  • Skin / pathology
  • Skin Abnormalities / pathology

Conflict of Interest Statement

The authors declare no competing interests.

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Citations

This article has been cited 7 times.
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