Ex vivo study shows novel, rapid, suture-free tenotomy technique for the equine deep digital flexor tendon.

This research study explores a new technique to sever the deep digital flexor tendon (DDFT) in horses, involving the use of surgical thread and ultrasound guidance, with promising results, despite some surrounding structural damage.

Introduction and Methodology

• The objective of the study was to assess the feasibility of using a novel method: thread-transection, for performing tenotomy (a surgical procedure to cut a tendon) on the deep digital flexor tendon (DDFT) in horses. The DDFT is a critical structure in equine limbs, playing a significant role in strength, flexibility, and overall function.
• Testing was performed on 39 equine limb specimens, split into 22 forelimbs and 17 hindlimbs.
• The procedure was executed under ultrasonographic guidance to accurately locate the DDFT. This method also assisted in avoiding damage to adjacent structures during the process.
• A surgical thread was inserted through two needle punctures (one lateral, one medial), around the DDFT utilizing a Tuohysi needle, then was moved back-and-forth, essentially sawing through the tendon until released from the initial entry point.

Results

• The technique successfully achieved complete transection of the DDFT in all 39 specimens. The average time for the procedure was approximately 8.6 minutes, indicating that this method is fairly quick and efficient.
• However, the study did find that iatrogenic damage (accidental harm caused by the medical intervention) to surrounding structures occurred in 44% of the limbs, with 15% of the limbs experiencing damage to more than one nearby structure.
• The most frequently damaged adjacent structure was the communicating branches of the palmar or plantar nerves. This, however, is not surprising considering that these delicate nerve structures are located very close to the DDFT.

Conclusion

• Overall, the research concluded that the thread-transecting technique for the tenotomy of the equine DDFT can be effective and rapid, without requiring any suturing.
• However, there is a considerable risk involved for damaging surrounding structures, which suggests that improvement or modification of the procedure might be necessary.
• This raises the need for further assessment and studies to understand the clinical significance of potential collateral damage in actual clinical cases, before advocating widespread adoption of the technique.