You might not be able to see a roarer from a mile away, but you sure can hear them. Horses with recurrent laryngeal neuropathy (RLN, often referred to as roarers due to the sound they make breathing) frequently require surgical intervention to both reduce the noise produced during exercise and to increase the amount of air they can take in while working.
Phil Cramp, BSc, BVM&S, MS, Dipl. ACVS, ECVS, MRCVS, a veterinarian at Rainbow Equine Hospital in Yorkshire, England, and Safia Barakzai, BVSc, MSc, Cert ES (Soft Tissue), DESTS, Dipl. ECVS, MRCVS, senior lecturer in Equine Surgery at the University of Edinburgh Royal (Dick) School of Veterinary Studies, recently reviewed the different surgical options currently available to treat horses with recurrent laryngeal neuropathy (RLN), their success rates, and morbidity (the rate of disease incidence after surgery).
In horses affected by RLN, the muscles that open and close the left side of the larynx as the horse breathes are paralyzed, causing the arytenoid cartilage (which closes over the trachea when a horse swallows) to droop into the left side of the airway. This effectively blocks the flow of air into the lungs. Clinical signs of disease include respiratory noise during exercise and reduced performance.
"The goals of surgery are to eliminate or reduce respiratory noise and/or improve athletic performance in affected individuals," Cramp said.
Choosing a Surgery
Cramp said that there are four factors to consider before selecting which surgical technique to use on a patient:
- The horse’s intended use