In vitro evaluation of a novel prosthesis for laryngoplasty of horses with recurrent laryngeal neuropathy.
A prosthesis, composed of a steel cable and stress-reducing washers, was developed to prevent failure of laryngoplasty, a common treatment for horses affected by recurrent laryngeal neuropathy. Laryngoplasties were performed on 15 cadaveric larynges using a polyester suture on one side and the cable prosthesis on the other. Each prosthesis was distracted at a displacement rate of 20 mm/s using a servohydraulic materials testing machine until laryngoplasty failed. Distraction force and actuator displacement were recorded and analysed. All 15 laryngoplasties performed with a suture failed at the muscular process at a mean +/- s.d. force of 55.8 +/- 13.1 N. Six laryngoplasties performed with the cable prosthesis failed at the muscular process at mean force 219.6 +/- 125.0 N. In the other 9, the arytenoid cartilage was avulsed from the larynx at mean force 206.4 +/- 75.3 N, and the cable then tore through the muscular process at mean force 357.0 +/- 32.0 N. The difference in force required to cause failure of laryngoplasty was significant (P<0.0001). Although the prosthesis resisted substantially higher forces than did the suture, the effects of the prosthesis in vivo must be evaluated.
Schumacher
J
J
Department of Farm Animal and Equine Medicine and Surgery, The Royal Veterinary College, University of London, Hatfield, Herts.
Wilson
A M
AM
Pardoe
C
C
Easter
J L
JL
D000818:Animals; D001193:Arytenoid Cartilage / Q000293:injuries / Q000503:physiopathology; D001696:Biomechanical Phenomena; D006734:Horse Diseases / Q000601:surgery*; D006736:Horses; D007818:Laryngeal Diseases / Q000601:surgery / Q000662:veterinary*; D007830:Larynx / Q000601:surgery*; D019736:Prostheses and Implants / Q000662:veterinary*; D019919:Prosthesis Implantation / Q000379:methods / Q000662:veterinary*; D012008:Recurrence; D013537:Sutures / Q000662:veterinary