Transrectal Ultrasonography of Equine Lumbosacral Nerves: Pilot Study in 28 Healthy Warmblood Horses.

This research study aims to elaborate the potential use of transrectal ultrasonography in observing and analyzing the lumbosacral nerves of horses, and to provide details about the procedure of image acquisition. A total of 28 healthy warmblood horses underwent said technique, and the variations in nerve measurements across the sample group are also discussed.

Objective and Methodology

• The main purpose of this study was to develop and understand a non-invasive method, i.e. transrectal ultrasonography, for examining the lumbosacral nerves in horses.
• This research intended to study the horses which were suspected of having lumbosacral plexopathy or injury.
• The sample consisted of healthy and sound horses marked by a clinical and lameness evaluation.
• The procedure involved obtaining ultrasound images of the lumbosacral nerves (categorized as L6, S1, and S2) from both the sides.

Outcomes and Observations

• The study comprised 28 warmblood horses ranging from 5 to 15 years, including 15 males and 13 females.
• These nerves showcased as tubular structures displaying a characteristic hyperechoic linear echo pattern under ultrasonography.
• There were no significant differences noticed between the vertical diameter measurements of the nerves on the right and left sides.
• The interplay among sex, age, and lumbosacral nerve was noted. Particularly, the L6 nerve in males was significantly larger than S1 in the youngest group.
• Interestingly, S2 nerve was consistently smaller than L6 or S1, irrespective of the category of age group or sex.

Conclusions

• Transrectal ultrasound proved a viable method for visualizing and measuring equine lumbosacral nerves in this study.
• Although the nerve sizes varied markedly across different horses, they presented bilateral symmetry within a single horse.
• This underscores the recommendation of side comparison when potential nerve damage is being investigated.