Clinical Research Abstracts of the British Equine Veterinary Association Congress 2015.

This study documents a treatment method for blackthorn plant thorn synovitis, an infection caused by blackthorn penetration in horses. The treatment is a two-stage surgical procedure which successfully healed all horses involved in the study, despite initial high levels of synovial fluid total protein and TNCC, typically associated with sepsis or contamination.

Research Aim and Methodology

• The aim of the study was to document the presentation, diagnosis, treatment, and outcome of horses affected by blackthorn plant thorn synovitis.
• The methodology was a series of cases where all the cases presented with an acute onset of synovitis within twenty-four hours of thorn penetration.
• Each case underwent a standardized clinical assessment, surgical treatment, and received aftercare. The surgical treatment was performed within 24 hours of presentation under general anesthesia, in two stages.

The Two-stage Surgical Procedure

• Stage 1 involved ultrasound-guided placement of a 20 gauge 35mm needle marker, which was used as a guide for electrosurgical dissection onto perisynovial thorn fragments.
• Stage 2 involved the use of endoscopic techniques using standard and novel portals to locate and remove thorn fragments and debris from synovial structures.

Results Summary

• Over a 24 month period, thirty-five cases met the study’s inclusion criteria.
• The most commonly affected structures were the fetlock joints (11 cases) and tendon sheaths (10 cases).
• All synovial fluid cultures were negative and all horses returned to full work and soundness five days after surgery.

Conclusions

• The consensus from a limited number of case series of blackthorn injury in humans has shown that surgical treatment is required for a successful outcome. This study builds on that consensus with horses.
• The two-stage surgical procedure allowed for accurate identification and removal of thorn material in all documented cases.
• Despite high pre- and post-operative synovial fluid total protein and TNCC levels, the outcome was positive in contrast with previous studies on synovial sepsis. This suggests that thorn synovitis cases have a different etiology from synovitis originating from sepsis or contamination.
• The study was reviewed and approved by the Ethics Committee of the School of Veterinary Medicine and Science at the University of Nottingham, with informed consent given by all horse owners for their animals’ inclusion in the study.