An ex vivo model to evaluate the effect of cyclical adductory forces on maintenance of arytenoid abduction after prosthetic laryngoplasty performed with and without mechanical arytenoid abduction.
OBJECTIVE
To (1) develop a model of cyclical adduction force on an abducted left arytenoid cartilage that mimics swallowing or coughing; (2) determine if arytenoid abduction by a clamp before knot tying will improve the maintenance of abduction under cyclical adduction testing.


METHODS
Experimental.


METHODS
Cadaveric equine larynges (n = 14).


METHODS
Left laryngoplasty performed using a single suture of #5 Ethibond with (n = 7) and without (n = 7) abducting the arytenoid with a clamp before knot tying. Each laryngoplasty was loaded cyclically from 2 to 26 N at 0.5 Hz for 5000 cycles in a servohydraulic test frame. Arytenoid displacement data were collected at 1 Hz intervals and median percent loss of abduction compared between groups. Significance was set at P < .05.


RESULTS
Median left arytenoid abduction distance was 16.9 mm (range, 9.8-19.8 mm). One larynx in each group failed at <1000 cycles. Loss of abduction was determined by progressive displacement of the testing actuator and confirmed by measurement. There was no difference in loss of abduction between clamped and non-clamped larynges after 5000 cycles. This model of cyclical adduction resulted in arytenoid displacements similar to those seen in the 1st week postoperatively.


CONCLUSIONS
Ex vivo cyclical adductory forces produced a significant loss of laryngoplasty abduction. The use of a clamp to abduct the arytenoid cartilage before knot tying did not reduce the loss of abduction.
Department of Veterinary Clinical Sciences, The Ohio State University, Columbus, Ohio.
Nathaniel R
NR
McClellan
Elizabeth M
EM
Santschi
Samuel D A
SD
Hurcombe
Alan S
AS
Litsky
D000818:Animals; D001193:Arytenoid Cartilage / Q000601:surgery*; D001696:Biomechanical Phenomena; D002102:Cadaver; D006734:Horse Diseases / Q000601:surgery*; D006736:Horses; D058753:Laryngoplasty / Q000662:veterinary*; D007830:Larynx / Q000601:surgery*; D008954:Models, Biological; D013537:Sutures / Q000662:veterinary