Gross anatomy, computed tomographic contrast tenography, and needle endoscopy of the equine medial digital flexor tendon sheath.
Abstract: To investigate the computed tomography (CT) and gross anatomy of the equine medial digital flexor tendon sheath (MDFTS), and the endoscopic anatomy and approach to the MDFTS. Methods: Ex vivo experimental study and one clinical case. Methods: Twelve clinically normal cadaveric hindlimbs. Methods: Dissection, native and contrast CT scans were conducted to evaluate the anatomy of the MDFTS. Based on these findings, the portal locations for the endoscopic approaches were determined. Six hindlimbs were used in the pilot phase and another six limbs were selected for the main study. Endoscopic images were reviewed by three observers for the quality of visualization of intrasynovial structures during endoscopy. Results: Intrasynovial structures that could consistently be identified during dissection and CT examination included the mesotenon in the proximal recess and two synovial plicae surrounding the medial digital flexor tendon. Communication between MDFTS and tarsal sheath varied among individual horses. Two portals were necessary to visualize the complete length of the MDFTS. Endoscopic entry was possible with both a needle scope and a conventional arthroscope; however, endoscopic examination was only feasible with the needle scope. The aforementioned intrasynovial structures could also be visualized endoscopically. One clinical case is presented with septic tenosynovitis due to a laceration with penetration of the MDFTS. Conclusions: Endoscopic examination of the MDFTS is possible with the use of a needle scope. Conclusions: Endoscopic lavage of the MDFTS might be indicated in cases of septic tenosynovitis of the MDFTS and/or tarsal sheath.
© 2025 The Author(s). Veterinary Surgery published by Wiley Periodicals LLC on behalf of American College of Veterinary Surgeons.
Publication Date: 2025-04-14 PubMed ID: 40223504PubMed Central: PMC12344221DOI: 10.1111/vsu.14263Google Scholar: Lookup
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- Journal Article
Summary
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The study investigates the possibility of using needle endoscopy to examine the medial digital flexor tendon sheath (MDFTS) in horses. Starting through dissection and CT scans, the study identifies specific structures in the MDFTS, establishes the best ways to visualize them, and confirms that endoscopic examination is feasible with a needle scope, providing a new approach to potentially treat cases of septic tenosynovitis of the MDFTS and/or tarsal sheath in horses.
Study Design and Methods
- The research began with an ex vivo experimental study involving twelve clinically normal cadaveric hindlimbs from horses.
- The study methods involved dissection, native and contrast CT scans to evaluate the anatomy of the MDFTS.
- Observations from the dissection and CT scans informed the identification of the ideal locations of the portals for endoscopic examination.
- For testing, six hindlimbs were initially used in a pilot phase while the remaining six formed the main study.
Results and Observations
- Intrasynovial structures consistently identifiable were a mesotenon in the proximal recess and two synovial plicae around the medial digital flexor tendon.
- Communication between MDFTS and the tarsal sheath showed variability between individual horses.
- Complete visualization of the MDFTS required the use of two entry portals.
- Both a needle scope and a conventional arthroscope could be used for endoscopic entry, however; a complete endoscopic examination was only achievable with the needle scope.
Case Study and Conclusions
- The study also reports a clinical case featuring a horse with septic tenosynovitis due to a laceration that penetrated the MDFTS.
- The needle scope endoscopic examination confirmed its efficacy in such examinations, thereby heralding its potential in the diagnosis and treatment of similar cases.
- The study, therefore, shows the possibility and feasibility of endoscopically examining the MDFTS in live horses using a needle scope, especially in cases related to septic tenosynovitis of the MDFTS and/or tarsal sheath.
Cite This Article
APA
Kerbert MP, Delling U, Verhaar N.
(2025).
Gross anatomy, computed tomographic contrast tenography, and needle endoscopy of the equine medial digital flexor tendon sheath.
Vet Surg, 54(6), 1133-1144.
https://doi.org/10.1111/vsu.14263 Publication
Researcher Affiliations
- Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany.
- Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany.
- Clinic for Horses, University of Veterinary Medicine Hannover, Hannover, Germany.
Conflict of Interest Statement
No conflict of interest to declare.
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