While headshaking can be a purely behavioral problem in many horses, it can also result from severe facial pain or irritation, possibly due to a nerve disorder. Some headshakers with nerve disorders are euthanized while others undergo a surgical procedure called caudal compression of the infraorbital nerve to relieve the pain. The procedure involves placing a tiny platinum coil into the infraorbital canal to put pressure on the infraorbital nerve. In theory, the coil’s continuous feedback should stop nerve firing, thereby corroborating the nerve as a source of facial pain or irritation.
A recent study suggests this surgery could be a viable option with a long-term success rate of nearly 50%; however, researchers are continually working to find a more effective treatment method for headshaking.
To evaluate the long-term success rate of caudal compression of the infraorbital nerve, Veronica Roberts, MA, VetMB MA, Dipl. ECEIM, MRCVS, a clinical fellow in equine medicine at the University of Bristol, England, and her team reviewed clinical records of 58 horses that underwent this surgery between June 2004 and January 2011 at the University of Liverpool or the Royal Veterinary College in England or at the Strömsholm Specialist Animal Hospital in Sweden. The horses, aged 1 to 17 years, were used for general riding, show jumping, eventing, or dressage and had a history of headshaking.
Key findings from the study included:
- Surgery was initially considered a success in 35 of 57 (63%) horses, but headshaking recurred between nine and 30 months later in nine horses;
- Practitioners repeated the surgery in 10 horses;