Biplanar High-Speed Fluoroscopy of Pony Superficial Digital Flexor Tendon (SDFT)—An In Vivo Pilot Study

• Published in: Veterinary sciences 2021-05, Vol.8 (6), p.92
• Main Authors: Wagner, Franziska C., Gerlach, Kerstin, Geiger, Sandra M., Gittel, Claudia, Böttcher, Peter, Mülling, Christoph K. W.
• Format: Article
• Language: English
• Subjects: Bone marrow; collagenase; equine; Fitness equipment; Fluoroscopy; gait; horse; Kinematics; Metacarpal; Musculoskeletal system; Pain; Skin; strain; Strain gauges; Tendinitis; Tendons; Ultrasonic imaging; Wound healing; XROMM
• ISSN: 2306-7381; 2306-7381
• DOI: 10.3390/vetsci8060092

The superficial digital flexor tendon (SDFT) is the most frequently injured structure of the musculoskeletal system in sport horses and a common cause for early retirement. This project’s aim was to visualize and measure the strain of the sound, injured, and healing SDFTs in a pony during walk and trot. For this purpose, biplanar high-speed fluoroscopic kinematography (FluoKin), as a high precision X-ray movement analysis tool, was used for the first time in vivo with equine tendons. The strain in the metacarpal region of the sound SDFT was 2.86% during walk and 6.78% during trot. When injured, the strain increased to 3.38% during walk and decreased to 5.96% during trot. The baseline strain in the mid-metacarpal region was 3.13% during walk and 6.06% during trot and, when injured, decreased to 2.98% and increased to 7.61%, respectively. Following tendon injury, the mid-metacarpal region contributed less to the overall strain during walk but showed increased contribution during trot. Using this marker-based FluoKin technique, direct, high-precision, and long-term strain measurements in the same individual are possible. We conclude that FluoKin is a powerful tool for gaining deeper insight into equine tendon biomechanics.