Mandibular nerve block in juvenile Nile crocodile: a cadaveric study

Area of Science:

• Veterinary Anatomy
• Comparative Neurology
• Reptilian Physiology

Background:

• The mandibular nerve block is crucial for pain management in various species.
• Limited information exists regarding its application in Nile crocodiles.
• Developing precise techniques is vital for welfare and research in crocodilians.

Purpose of the Study:

• To establish and evaluate a novel technique for performing a mandibular nerve block in Nile crocodiles.
• To identify reliable anatomical landmarks for accurate needle placement.
• To assess the distribution of injected contrast medium and nerve staining.

Main Methods:

• An experimental cadaveric study involving 16 juvenile Nile crocodile heads.
• Dissection, computed tomography (CT), and methylene blue/iohexol injections were utilized.
• Needle insertion was performed through the external mandibular fenestra, with varying injection volumes (0.5 mL and 1.0 mL).

Main Results:

• The external mandibular fenestra was confirmed as a reliable landmark for needle insertion.
• CT imaging showed accurate needle tip placement in 100% of cases.
• Both injection volumes resulted in significant rostrocaudal and dorsoventral spread of contrast, with larger volumes showing greater distribution (p < 0.001).

Conclusions:

• The developed technique for mandibular nerve block in Nile crocodiles is feasible and safe.
• Successful staining of the mandibular nerve was achieved, suggesting potential for effective sensory blockade.
• This technique offers a valuable tool for pain management and research in Nile crocodiles.