08/19/2025
Radial nerve
Who ever said radial nerve injury in the previous post was correct ###
When this nerve gets injured it can be quite frightening for the owner, as often the horse will present by dragging the toe unable to extend the forelimb, stumbling or struggling to weightbare.
I will preface this to say it is quite rare for this type of injury to occur and similar to the Suprascapular nerve the tendency for both of these nerves to succumb to trauma is because both at some point sit closer to the surface, the superficial branch of the Radial nerve sits quite cutaneous on the lateral side exiting the lateral head of the Triceps (Triceps are the extensors of the elbow) while the deep branch innervates the extensors of the forelimb. others nerves are often protected deep beneath the surface.
I personally have only ever encountered one case in all the years I have been around horses (over 30 years), and it was a foal who we think mum had maybe stepped on it while in the stable and although it looked very dramatic it made a full recovery with some veterinary intervention and time for the body to heal
Trauma is the most likely cause, extreme abduction (out to the side) or protraction (stretching back) of the forelimb can attribute, so slips or falls, laying on the side for a lengthy amount of time (anaesthetised), and of course blunt force Trauma,
Sensation can be affected aswell as motor function, the radial nerve innervates all the extensors in the forelimb and the superficial branch of the nerve innervates the lateral cutaneous antebrachium
The lacertus fibrosus links the Biceps Brachii to the Extensor Carpi Radialis tendon, remember each tendon in the lower limb does attach to a muscle in the upper limb which then connects to the rest of the body, so if the horse is unable to use the stay apparatus then the horses may not be able to use the vital energy saving system to the muscles.
Veterinary intervention as early as possible is important for appropriate diagnosis and to determine the extent of damage as with all nerve injuries the outcome can vary depending on the severity of the damage to the nerve, guesswork could delay the appropriate treatment. Also the other forelimb will need careful watching or support as it will be taking an extra load onto it, and remember the rest of the body will also offload an injury site
But like I say it is quite rare but once you see it you never forget