Laryngeal Tie-forward Procedure Research Articles

Outcome analysis of 95 harness racehorses with confirmed dorsal displacement of the soft palate treated with laryngeal tie-forward surgery.

The laryngeal tie-forward (LTF) procedure is commonly used to treat intermittent dorsal displacement of the soft palate (iDDSP). There is a wide range in reported efficacy of treating horses with and without a definitive diagnosis of iDDSP. To evaluate the racing performance of harness racehorses in which iDDSP had been definitely diagnosed and treated solely with the LTF procedure. Retrospective case series. Ninety-five harness racehorses were treated with LTF for confirmed iDDSP. A definite diagnosis of iDDSP was made with high-speed treadmill or overground endoscopy. Upper respiratory tract (URT) disorders, short-term complications, and horses returning for recurrence of URT problems were recorded. Performance before and after LTF was assessed by reviewing career race records and comparing performance index (PI), and racing speed marks from the baseline, preoperative, and postoperative periods. The effect of basihyoid-cricoid (BC) net distance shortened on racing performance was assessed. Postoperatively, PI increased in 36/54 (67%, 95% CI 54%-79%) of experienced racehorses, and 44/67 (66%, 54%-77%) established or improved their racing speed mark relative to the preoperative period. As a group, PI decreased by a mean (SE) of 0.9 (0.17) points (P<.001) prior to diagnosis/surgery. Postoperatively, PI increased by 0.5 (0.16) points (P=.003), and racing speed improved by 0.83 (0.22)s (P<.001). Twenty-five percent (17%-34%) and 49% (39%-60%) of horses did not demonstrate a decline in PI and racing speed prior to diagnosis, respectively. Net BC distance shortening did not affect performance postoperatively. Twenty of 95 horses (21%, 13%-29%) had confirmed recurrence of iDDSP 46-708days postoperatively. Not all horses were evaluated with exercising endoscopy postoperatively. Racehorses inevitably develop other racing-related problems which confound studies of this nature. This study provides scientific support for the use of LTF to treat iDDSP in harness racehorses although iDDSP seems to affect harness racehorses differently as individuals.

Longus capitis and rectus capitis ventralis minor rupture in a horse following general anaesthesia for a laryngeal tie-forward procedure

The authors present a case of a racehorse with acute respiratory distress, bilateral epistaxis and laryngeal swelling following a laryngeal tie-forward procedure. An emergency tracheostomy was performed following brief endoscopic...

Ex-vivo Mechanical Testing of Novel Laryngeal Clamps Used for Laryngeal Advancement Constructs.

Rostral laryngeal advancement, also known as laryngeal tie-forward, is used to treat horses for intermittent dorsal displacement of the soft palate and has a morbidity rate of about 6%. We hypothesized that a novel laryngeal clamp would prevent morbidity associated with the sutures tearing through the thyroid cartilage. Larynges (n = 35 horses) were used for ex vivo testing. For uniaxial testing, 15 equine larynges were tested in one of three laryngeal tie-forward constructs [standard laryngeal tie-forward; modified laryngeal tie-forward using a suture-button; and modified laryngeal tie-forward using a laryngeal clamp]. For biaxial testing, 20 larynges were tested in one of two treatment groups: laryngeal tie-forward and laryngeal tie-forward using a laryngeal clamp. Constructs were tested in single cycle-to-failure. Statistical analyses were performed using ANOVA for uniaxial testing and t-tests for biaxial testing. The laryngeal tie-forward using a laryngeal clamp construct was superior to laryngeal tie-forward and laryngeal tie-forward using a suture-button constructs in resistance to pullout in uniaxial testing. The laryngeal tie-forward using a laryngeal clamp presented a significantly different method of failure than the standard laryngeal tie-forward in the biaxial testing. Failure modes for each construct were primarily by suture failure at the clamp (laryngeal tie-forward using a laryngeal clamp), suture pullout through the thyroid cartilage, or, less commonly, tearing of the cricothyroid ligament (laryngeal tie-forward). In uniaxial testing, the laryngeal tie-forward using a laryngeal clamp failed most commonly due to tearing of the cricothyroid ligament, whereas the standard laryngeal tie-forward and the laryngeal tie-forward using a suture-button failed due to the tearing of the cartilage. The laryngeal clamps provided greater stiffness, load at yield, and tensile stress at yield than did the standard construct. Laryngeal clamps may offer an alternative to standard methods of anchoring the thyroid cartilage when performing the laryngeal tie-forward procedure. Further testing and clinical trials are needed to elucidate the utility of the laryngeal tie-forward using a laryngeal clamp.

Racing performance of National Hunt thoroughbred racehorses after treatment of palatal dysfunction with a laryngeal tie-forward procedure and thermocautery of the soft palate with or without aryepiglottic folds resection.

To assess racing performance of National Hunt thoroughbred (NH) racehorses with a definite diagnosis of palatal dysfunction treated with a laryngeal tie-forward procedure (LTF) and soft palate cautery (SPC) with or without transendoscopic laser excision of the aryepiglottic folds (TLEAF) and to determine correlation between performance measures. Retrospective cohort study. National Hunt racehorses treated with LTF, SPC ± TLEAF (n = 44) and nonaffected controls (n = 88). Performance was evaluated by using Racing Post ratings (RPR), race earnings (RE), and performance index (PIndex). Affected horses were compared with nonaffected horses. The effect of TLEAF and correlations between measures were analyzed. Racing Post rating, RE and PIndex improved by 50%, 26%, and 12% in treated, and by 50%, 39%, and 24% in control horses, respectively, when measurements were evaluated for the median of three presurgical and postsurgical races. Lower postsurgical performance was detected when five postsurgical races were compared with two presurgical races (P ≤ .03). The number of postsurgical earnings rated at zero was greater in treated horses than in control horses (P < .05). Race earnings and RPR correlated more strongly (r = 0.634-0.796) than PIndex and other measures (r = 0.378-0.692). Postsurgical performance of NH racehorses with palatal dysfunction after LTF and SPC ± TLEAF was decreased compared with unaffected controls. The negative effect of TLEAF on performance was detected. Although LTF is widely performed in NH racehorses, it may not be the most efficient treatment for palatal dysfunction.

Clinical outcome in two adult horses treated for cleft palate with laryngeal tie-forward surgery

Two adult sport horses were referred for respiratory noise, exercise intolerance, coughing and nasal discharge containing food material. An asymmetrical, mild to moderate defect of the soft palate was diagnosed...

The effect of the laryngeal tie-forward procedure and soft palate cautery on nasopharyngeal diameter in horses

The laryngeal tie-forward (LTF) procedure has been shown to move the larynx rostrally and dorsally whilst repositioning the basihyoid bone caudally and dorsally. Other studies have shown that the position...

A Modified Laryngeal Tie‐Forward Procedure Using Metallic Implants for Treatment of Dorsal Displacement of the Soft Palate in Horses

To describe a modified laryngeal tie-forward procedure (LTFP) using metallic implants. Retrospective case series. Twenty-seven horses (including 24 race horses) with dorsal displacement of the soft palate (DDSP) or palatal instability (PI) diagnosed using high-speed treadmill endoscopy (n = 15), history and resting examination (n = 8), or dynamic endoscopy over ground (n = 4). All horses underwent the modified LTFP. Modifications of the surgical procedure consisted in the use of 3 metallic stents called Suture Button(TM) through which the sutures are threaded and in a tying technique that involved a single knot connecting left and right suture loops (versus tying each separately). Lateral radiographs were taken 24 hours after surgery. Follow-up was obtained by telephone communication with trainers or owners. Surgery was performed without complications on all horses. The 3 metallic buttons were clearly visible on the postoperative radiographic examination. No evidence of suture breakage was observed 24 hours postoperatively based on radiographs. In other aspects, this technique is not very different from that originally described by Ducharme et al; it is an innovation that could offer some advantages to the surgeons and increase suture resistance to pullout from the thyroid cartilage. Our technique was used without complication in a small group of horses and return to performance may be similar to the original technique.

Effect of Head Position on Radiographic Assessment of Laryngeal Tie‐Forward Procedure in Horses

To assess the effect of head position on relative position of the larynx and hyoid apparatus in horses with palatal dysfunction, and to define a standard position for radiographic assessment of laryngeal tie-forward. Prospective clinical study. Adult horses (n=9) with palatal dysfunction. Left lateral radiographs of the larynx were obtained pre and postoperatively for 3 different head positions (flexed=90 degrees ; neutral=100 degrees ; extended=115 degrees ). Distance between thyrohyoid bone and thyroid cartilage was measured. Data were analyzed to investigate differences between head positions, and to compare differences between pre- and postoperative measurements. Head position had a significant effect on relative position of the larynx and hyoid apparatus preoperatively. There was no significant difference in postoperative measurements of the 3 head positions. A significant difference between pre- and postoperative measurements was found with the head in the neutral or extended position whereas there were no significant differences between pre- and postoperative measurements using the flexed position. Head position affects the relationship between the hyoid apparatus and larynx preoperatively, with greatest distance occurring when the head is extended. In a flexed position, it is not possible to ascertain whether laryngeal position has changed postoperatively. A standardized head position is necessary when assessing the laryngeal tie-forward procedure radiographically. An extended head position is most useful for this assessment.

Racing performance following the laryngeal tie‐forward procedure: A case‐controlled study

The laryngeal tie-forward procedure (LTFP) is becoming widely used for correction of dorsal displacement of the soft palate (DDSP) despite the absence of an evidence-based assessment of its efficacy. The LTFP returns racing performance to preoperative baseline levels and to that of matched controls; and post operative laryngohyoid position is associated with post operative performance. Case-controlled study of racehorses undergoing a LTFP for dorsal displacement of the soft palate at Cornell University between October 2002 and June 2007. The presence of at least one post operative start and race earnings ($) were used as outcome variables. Controls were matched by age, breed and sex from the third race prior to surgery. A novel radiographic reference system was used to determine laryngohyoid position pre- and post operatively. Data for definitively and presumptively diagnosed cases were analysed separately. During the study interval, 263 racehorses presented, of which 106 were included in the study; 36 had a definitive diagnosis of DDSP and 70 a presumptive diagnosis. Treated horses were equally likely to race post operatively as controls in the equivalent race. Treated horses had significantly lower earnings in the race before surgery than matched controls. The procedure moved the basihyoid bone dorsally and caudally and the larynx dorsally and rostrally. A more dorsal post operative basihyoid position and more dorsal and less rostral laryngeal position were associated with an increased probability of racing post operatively. Horses undergoing a LTFP are as likely to race post operatively as matched controls. The procedure restores race earnings to preoperative baseline levels and to those of matched controls. This study provides strong evidence supporting the use of the LTFP in racehorses. Further work is needed to determine the relationship between laryngohyoid conformation and nasopharyngeal stability in horses.