Recurrent Laryngeal Neuropathy: What the Research Says
Evidence from 56 peer-reviewed studies
1 Systematic Review
1 RCT
11 Cohort Study
19 Case Report
24 Expert Opinion
What Professionals Should Know
- •Resting endoscopy is a reliable screening tool—normal results (grades 1-2) effectively rule out laryngeal dysfunction in most cases, avoiding unnecessary exercise testing
- •Grade 3 resting findings warrant dynamic endoscopy, as this intermediate grade shows high variability in exercise performance and cannot reliably predict outcome
- •Dynamic endoscopy remains essential because resting exams miss ~9-10% of clinically affected horses and cannot identify other causes of airway obstruction
- •Modified laryngoplasty with cricoarytenoid joint ankylosis provides superior long-term maintenance of arytenoid abduction compared to standard laryngoplasty, reducing the need for revision surgery in horses with laryngeal hemiplegia
- •The procedure achieves mechanical stability through joint fusion rather than relying on suture tension alone, offering more durable results for performance horses
- •Consider this modified approach for horses requiring laryngoplasty, particularly those with high performance demands where loss of abduction would be career-limiting
- •Yearling sale videoendoscopic assessments showing grade II.2 or worse laryngeal dysfunction are at significantly increased risk of requiring surgery later; this should inform purchasing decisions and expected outcomes
- •Many horses requiring prosthetic laryngoplasty had relatively mild yearling findings (≤grade II.2), suggesting laryngeal disease often deteriorates after sale—continued monitoring of horses with early-grade dysfunction is warranted
- •Laryngeal grading at yearling sales has meaningful predictive value for future surgery risk and should be considered alongside other pre-purchase evaluation findings
- •Draft pulling horses experience high prevalence of respiratory conditions during athletic activity; veterinarians should routinely screen for EIPH and RLH in working draft horses to identify affected animals early
- •The near-universal presence of tracheal mucus (82%) in draft pullers suggests this may be a normal response to the intense aerobic demands of pulling competitions rather than a pathological condition requiring intervention
- •Since traditional risk factors (weight, height, age, pulling amount) did not predict respiratory disease in this population, individual endoscopic examination is necessary for accurate diagnosis rather than relying on demographic or performance factors
- •Pre-purchase examinations should anticipate that 3 in 4 National Hunt horses will have some detectable abnormality; focus assessment on identifying those likely to impact racing performance rather than cosmetic findings
- •Metacarpal/metatarsal exostoses and tarsal-plantar desmitis are highly prevalent in this population—consider these findings in context of individual horse's intended use rather than as automatic deal-breakers
- •Buyers and vendors should understand that age, sex, and year of birth significantly influence abnormality prevalence; use this data to set realistic expectations during pre-purchase negotiations
- •Modified laryngoplasty is effective for returning racehorses with recurrent laryngeal neuropathy to competitive performance levels within 6 months post-surgery
- •Expect a performance dip in the immediate post-operative period (first quarter), but horses typically recover to pre-disease performance by Q2
- •Long-term racing longevity appears unaffected by the surgery, supporting it as a viable treatment option for maintaining racing careers
- •When evaluating harness racehorses for poor performance or respiratory noise, consider breed-specific susceptibility patterns to URT obstructions as part of diagnostic approach
- •Standardbred and Coldblooded Trotter horses may require breed-tailored screening protocols for different types of URT obstructive disorders
- •Genetic factors play a significant role in URT obstruction risk; breeding decisions should account for breed predispositions to these conditions
- •Laryngeal ultrasonography should be incorporated into diagnostic protocols for suspected recurrent laryngeal neuropathy, as it is more accurate than resting endoscopy alone
- •Hyperechogenicity on ultrasound of the left cricoarytenoideus lateralis muscle is a reliable indicator of abnormal arytenoid movement during exercise
- •Treadmill endoscopy remains the gold standard for assessment, but ultrasonography offers a non-exercise complementary diagnostic tool with high specificity to reduce false positives
- •Resting endoscopy alone is insufficient for diagnosing dynamic upper airway problems in performance horses—exercising videoendoscopy is essential for accurate assessment
- •Pharyngeal wall collapse is the most common finding in nonracing horses with respiratory complaints; consider this when investigating poor performance or abnormal breathing
- •Head and neck position during exercise significantly affects airway visualization—horses may require flexion positioning during endoscopy to reveal obstructions that affect performance
- •A single endoscopic examination on one day may not reliably diagnose recurrent laryngeal neuropathy; consider repeat examinations 24-48 hours apart to increase diagnostic confidence
- •When interpreting endoscopic grades from different veterinarians, expect some variation (63% agreement); ideally use the same experienced examiner for serial assessments
- •Intraobserver reliability is good, so sequential examinations by the same veterinarian are more reliable for monitoring progression or treatment response than comparing grades across different examiners
- •Monitoring SAA and fibrinogen levels postoperatively can help you assess whether the inflammatory response is proportional to the surgical procedure performed—unusually elevated levels may indicate infection or complications
- •WBC counts alone are insufficient for postoperative infection monitoring; use acute phase proteins (SAA, fibrinogen) and iron levels alongside clinical signs for better detection of problems
- •Understanding the expected inflammatory response timeline (peaks at days 1-3, gradually declining by day 11) helps you distinguish normal healing from pathological inflammation when evaluating recovery
- •Laryngoplasty successfully returns most National Hunt horses to racing with short-term performance comparable to unaffected peers, making it a viable treatment option for RLN
- •Expect roughly half of operated horses to improve performance, but plan for potentially shorter racing careers than non-affected horses
- •The procedure appears to restore immediate function effectively, but monitor these horses for earlier-than-normal retirement from racing
- •RLN does not provide additional benefit over laryngoplasty and ventriculocordectomy alone for horses with grade III laryngeal hemiparesis—consider omitting RLN to avoid denervation complications
- •Approximately half of treated horses show objective racing performance improvement regardless of RLN status; set realistic expectations with owners that surgery may not restore pre-disease performance
- •Owner/trainer subjective impressions of improvement are unreliable; use objective performance data (racing times, placings) to counsel clients on realistic outcomes
- •When selecting suture material for prosthetic laryngoplasty, expect polyester to elongate more overall but show less knot slippage than UHMWPE alternatives—trade-offs exist between construct stability and knot security
- •Consider applying cyanoacrylate to polyester knots as a simple intraoperative step to reduce knot elongation by ~1 mm and help preserve long-term arytenoid abduction
- •UHMWPE tape appears most resistant to total construct elongation and may better maintain surgical correction over time, though knot stability requires further investigation
- •Dorsolateral pharyngeal dissection and septum incision during laryngoplasty carry high risk of damaging the external cranial laryngeal nerve—modify surgical technique or use alternative approaches where possible
- •Gentle retractor placement and minimal retraction force are critical as the retractor blade directly compresses multiple nerve branches in all cases
- •Consider anatomical variation between individuals; some vagal branches were inconsistently present, so intraoperative identification and careful dissection around suspicious structures is essential
- •If a horse develops persistent coughing or swallowing difficulties after laryngoplasty, prosthesis removal is a viable treatment option with good success rates (66-75%)
- •Arytenoid abduction grade does not predict which horses will respond positively to prosthesis removal, so clinical response rather than endoscopic findings should guide management decisions
- •Expect about 1 in 30 laryngoplasty cases to require prosthesis removal, so counsel clients appropriately about potential post-operative complications
- •You can now assess the CAD muscle using standard ultrasound equipment at the clinic or barn without requiring referral for advanced imaging
- •The technique is simple: displace the larynx laterally with one hand while scanning transcutaneously with the other—practice on normal horses first
- •This method could support earlier or more frequent monitoring of horses at risk for or recovering from laryngeal neuropathy, potentially improving outcomes
- •A new surgical technique for recurrent laryngeal nerve paralysis based on human medical practice may provide an alternative to existing equine procedures, potentially improving outcomes for affected horses
- •Direct nerve transplantation from cervical nerves could offer selective reinnervation of laryngeal muscles, though clinical efficacy and long-term outcomes require further investigation
- •Standing laryngeal surgery is now feasible using cervical plexus blocks, eliminating general anesthesia risks in horses with poor prognosis for recovery
- •This technique provides an alternative for horses where recumbency poses safety concerns or where rapid return to function is critical
- •Practitioners should consider referral for standing prosthetic laryngoplasty in suitable candidates to improve surgical outcomes and reduce perioperative complications
- •Resting laryngeal endoscopy findings alone underestimate severity of airway dysfunction in horses with recurrent laryngeal neuropathy; dynamic exercise assessment is essential for complete pre-operative evaluation
- •Laryngoplasty significantly improves rima glottidis area during exercise, but post-operative monitoring is critical as over one-third of treated horses develop new upper airway obstructions requiring ongoing management
- •Resting arytenoid abduction angle post-laryngoplasty is a useful clinical indicator to predict exercise-induced airway function without requiring repeat dynamic endoscopy
- •Prosthetic laryngoplasty carries a risk of upper esophageal incompetence developing months to years post-operatively; monitor for persistent or delayed-onset coughing and dysphagia.
- •Iatrogenic damage to pharyngeal muscles, esophageal musculature, or their innervation during laryngoplasty can compromise swallowing safety—careful surgical technique minimizing collateral trauma is essential.
- •Horses with post-laryngoplasty coughing, especially when eating, warrant endoscopic evaluation to assess for esophageal reflux or obstruction before complications progress to food impaction.
- •CO2 laser debridement of the cricoarytenoid joint combined with laryngoplasty may help prevent the common post-operative loss of arytenoid abduction seen with laryngoplasty alone in horses with recurrent laryngeal neuropathy
- •The procedure induces cartilage necrosis and fibrosis that stabilizes over time without compromising airway flow, suggesting a biological mechanism for maintaining abduction
- •This combined approach warrants consideration for horses undergoing laryngoplasty, particularly those at high risk for abduction loss
- •Week 6 postoperative endoscopic assessment is more predictive of long-term laryngoplasty outcome than week 1 assessment; use week 6 findings for prognostication rather than early postoperative grades
- •Resting arytenoid abduction grade does not reliably predict stability during exercise, so horses with adequate resting abduction may still develop dynamic collapse during work
- •Approximately 1 in 5 laryngoplasty cases will show cartilage instability during exercise despite adequate resting abduction; consider this when setting post-operative expectations with owners
- •Laryngeal prosthesis effectiveness for treating RLN is not compromised by patient age, allowing treatment consideration across all age groups
- •Prosthesis location choice can be based on surgical accessibility and anatomical factors rather than age-related concerns about tissue response
- •Standardized tensioning protocols enable consistent prosthesis placement and predictable airway outcomes regardless of horse age
- •Consider using 2-3 laryngeal prostheses rather than a single prosthesis to maximize airway opening in horses undergoing laryngoplasty for paralysis.
- •Maintain suture tension around 15 N during laryngoplasty procedures to achieve optimal rima glottidis area without excessive tension.
- •Prosthesis placement location is less critical than the number used and tension applied—focus on achieving proper load rather than precise anatomic positioning.
- •Laryngoplasty suture placement must avoid excessive pressure on the arytenoid muscular process to prevent progressive cartilage necrosis and suture pull-through
- •Monitor horses post-laryngoplasty for signs of recurrent airway obstruction, as gradual cartilage failure may progress over weeks before catastrophic failure occurs
- •Consider postoperative infection prevention protocols, as low-grade infection combined with mechanical stress may accelerate laryngoplasty failure
- •Adding ventriculocordectomy to laryngoplasty may improve rima glottidis opening and reduce suture-related complications by requiring less tension on the prosthetic suture
- •This combined surgical approach could potentially improve airway caliber in horses with laryngeal hemiplegia, though clinical outcomes require in vivo confirmation
- •The mechanical advantage gained may be particularly beneficial in cases where maximum airway opening is desired or where suture-related complications (nerve damage, dehiscence) are a concern
- •Surgeons should not be discouraged by moderate (grade 3) long-term laryngeal abduction after laryngoplasty, as it does not predict poor racing performance in National Hunt horses
- •Horses with excellent immediate postoperative abduction (grade 1) paradoxically lose more abduction over time; moderate initial abduction (grade 3) appears more stable
- •Abduction grade alone should not be used as a prognostic indicator for postoperative racing success in racehorses
- •Laryngeal hemiplegia causes measurable cellular changes in muscle fiber composition that shift toward fast-twitch glycolytic fibers, which may affect long-term muscle recovery potential
- •Grossly normal laryngeal muscles can still show microscopic denervation changes, meaning subclinical nerve damage may be more widespread than clinical signs suggest
- •Understanding these cellular-level changes may inform future treatment strategies for laryngeal muscle regeneration or reinnervation therapies
- •Guttural pouch chondroids can be safely removed in standing sedated horses using a modified Whitehouse approach, avoiding general anesthesia risks and costs
- •Most horses (80%) return to full athletic function post-operatively, making this a viable treatment option for cases refractory to medical management
- •Pre-operative evaluation should include endoscopy and radiography to confirm diagnosis and assess for concurrent conditions like dysphagia or laryngeal neuropathy that may affect prognosis
- •This minimally invasive approach offers an alternative to traditional general anaesthesia surgical techniques, potentially reducing perioperative risks and recovery time
- •Standing sedated procedure may improve client convenience and reduce costs associated with general anaesthesia and hospitalization
- •Technique targets both noise reduction and functional airway improvement in horses with laryngeal hemiplegia
- •This uncommon upper airway problem can only be diagnosed using high-speed treadmill videoendoscopy—standard endoscopy at rest will miss it.
- •Affected horses are predominantly young males (2-5 years) in racing disciplines; consider this diagnosis in Thoroughbreds and Standardbreds with poor performance or respiratory noise that fail other diagnostic workups.
- •The condition may develop after previous laryngeal surgery for RLN, suggesting a possible link to advanced adductor nerve involvement requiring further investigation.
- •Suture anchor implants may be advantageous if minimizing initial abduction force is clinically desirable, though long-term stability data is needed
- •Tie-bolt implants offer superior mechanical durability and resistance to cyclic loading degradation, potentially providing longer-lasting surgical outcomes
- •Choice between implant types should consider both surgical ease (suture anchor advantage) and long-term mechanical stability (tie-bolt advantage) based on individual case requirements
- •The titanium corkscrew anchoring technique offers biomechanical advantages over traditional Jamshidi needle methods, requiring less force and causing less tissue disruption during laryngoplasty
- •Corkscrew implantation may enable more physiologic muscle function by minimizing CAD muscle indentation and laryngeal rotation, potentially improving long-term surgical outcomes
- •This technique opens possibilities for combined nerve graft procedures in recurrent laryngeal neuropathy cases, which could improve functional recovery beyond current single-procedure approaches
- •CFD modeling offers a non-invasive tool to predict and compare outcomes of different RLN surgical procedures before clinical application
- •This computational approach may help surgeons optimize technique selection and refinement for individual cases of laryngeal hemiplegia
- •Future development of CFD analysis could reduce trial-and-error in surgical planning for obstructive airway disorders
- •When evaluating laryngeal endoscopy videos, use frame-by-frame playback at known frame rates and apply this decision tree to achieve more consistent, objective grading of laryngeal function across cases.
- •The critical distinction between grades III.1 and II.2 depends on whether arytenoid abduction is maintained for at least 0.2 seconds—use this as your timing benchmark during video review.
- •This standardized approach reduces subjective interpretation and improves communication with referring veterinarians by providing consistent, evidence-based laryngeal grades.
- •While two-prosthesis techniques with single-loop arytenoid fixation dominate practice, evidence suggests alternative biomechanical approaches may offer advantages—consider exploring these if outcomes warrant it
- •Standing sedation is increasingly used for laryngoplasty (36% of respondents), offering potential advantages in recovery and cost—evaluate feasibility in your facility
- •Antimicrobial protocols vary widely with no consensus on duration or local vs. systemic use—audit your current practice against evidence-based guidelines to optimize outcomes
- •Colombian Paso horses with abnormal respiratory sounds and poor exercise performance should be evaluated for dynamic laryngeal collapse and arytenoid cartilage pathology via overground endoscopy, as these are highly prevalent (87.5%) in this breed.
- •The breed's characteristic high poll flexion during special gaits appears to predispose to laryngeal dysfunction; consider this when assessing respiratory issues and performance problems.
- •Ventromedial luxation of the arytenoid is notably overrepresented in this breed compared to others, suggesting breed-specific anatomical or biomechanical vulnerability warranting specific diagnostic attention.
- •A dynamic system could potentially provide additional arytenoid abduction beyond what fixed laryngoplasty alone achieves, though clinical benefit remains to be proven
- •This is early-stage technology development; results are from dissected larynges and do not yet demonstrate effects on actual airway function or patient outcomes
- •Further research is needed to determine if this system would reduce post-operative stridor or improve exercise tolerance compared to conventional laryngoplasty
- •Understanding the precise anatomical boundaries of the vestibulum esophagi is critical for surgeons performing laryngoplasty—awareness alone reduced complication rates from 72% to 9%
- •When placing sutures through the arytenoid muscular process during laryngoplasty, stay rostral and avoid deep penetration to prevent entering the esophageal lumen or adventitia
- •This anatomical knowledge should be emphasised in surgical training and case planning before performing prosthetic laryngoplasty procedures
- •FASTak II anchors may improve surgical outcomes in laryngoplasty by requiring less suture tension to achieve adequate arytenoid abduction, potentially reducing postoperative loss of function
- •Consider FASTak II technique as preferred attachment method over traditional suture patterns for horses undergoing laryngoplasty
- •Lower load requirements with FASTak II may translate to improved long-term durability of the surgical repair
- •Metallic button reinforcement of cricoid sutures may reduce loss of arytenoid abduction and improve long-term stability of laryngoplasty, potentially reducing recurrence of clinical signs.
- •Standard single-pass suture techniques show greater suture migration under cyclic loading; consider reinforcement strategies in cases at high risk of recurrence.
- •These ex vivo findings suggest metallic button constructs warrant in vivo clinical trials, but until then, standard techniques remain the clinical reference.
- •Do not expect single genetic tests to reliably diagnose or predict equine airway diseases; genetic risk must be assessed alongside environmental factors and management practices
- •Family history and individual genetics should inform breeding decisions, but environmental control (dust, ammonia, exercise management) remains critical for disease prevention
- •Emerging genetic profiling panels may eventually help identify high-risk individuals, but these tools are not yet clinically validated—consult current research before adoption
- •Prosthetic laryngoplasty combined with laser ventriculocordectomy is an effective surgical option for treating RLN in racing Thoroughbreds seeking to maintain or improve performance
- •Polyurethane offers a viable prosthetic material choice for laryngoplasty procedures, providing surgeons with an alternative to traditional materials
- •This procedure restores normal airway mechanics, addressing the performance-limiting airway obstruction caused by RLN
- •Laryngoplasty repairs lose significant abduction under physiologic-level forces simulating early postoperative swallowing and coughing—postoperative management restricting these activities may be critical
- •Using a clamp to pre-abduct the arytenoid before knot tying does not improve long-term maintenance of abduction, so this surgical refinement may not be worth the additional operative time
- •Consider modified postoperative protocols or alternative surgical techniques if mechanical failure occurs in nearly 7% of cases within the first few hundred cycles
- •Understanding cricothyroid muscle anatomy and innervation is essential for veterinarians considering functional electrical stimulation as treatment for recurrent laryngeal neuropathy
- •Proper electrode placement requires detailed knowledge of muscle neuroanatomy to effectively recruit muscle fibers and improve laryngeal patency
- •This anatomic foundation supports development of therapeutic interventions for horses with upper airway obstruction secondary to laryngeal nerve damage
- •The ALPS system may offer improved durability and reduced motion at the surgical site compared to traditional single-suture laryngoplasty, potentially reducing recurrence of clinical signs
- •Reduced distraction with ALPS could translate to better long-term arytenoid positioning and functional outcomes in RLN cases
- •In vitro findings are promising but clinical trials are needed to confirm whether improved mechanical properties translate to better surgical success rates in living horses
- •Do not rely on owner-reported noise patterns alone to diagnose specific upper respiratory conditions—many horses with abnormal noise have complex, multifactorial obstructions that require DRE to identify completely
- •Perform dynamic respiratory endoscopy in all racehorses presenting with abnormal respiratory noise, even if the noise pattern seems characteristic, to avoid missing concurrent conditions that may affect performance
- •While whistling and roaring are reasonably specific for laryngeal pathology, gurgling and rattling are non-specific markers that commonly indicate palatal dysfunction but frequently coexist with other obstructions
- •Neuroprosthetic stimulation of the recurrent laryngeal nerve can restore effective airway opening in horses with laryngeal paralysis, offering an alternative to conventional prosthetic laryngoplasty
- •Expect increasing tissue impedance in the first 2 months post-implantation; device programming may need adjustment during this period
- •This approach may be particularly suitable for horses with grades I-III laryngeal dysfunction; results in grade IV cases were poor
- •This in vitro model enables systematic testing and optimization of laryngoplasty implants and suture techniques before clinical application, reducing need for trial-and-error in surgery
- •The validated pressure and flow data provide objective benchmarks for evaluating whether new prosthetic designs actually improve airway function during maximal exercise conditions
- •Surgeons can use findings to understand which suture materials and abduction angles best maintain upper airway patency under the high-demand conditions horses experience at speed
- •When performing arytenoid prosthesis placement, prioritise double suture patterns over single patterns for improved construct stability and resistance to failure
- •Ensure sutures engage the spine of the muscular process, as this anatomical engagement provides superior biomechanical strength compared to alternative positioning
- •Design surgical approach to minimise muscular process failure, which is the most common failure mode in poorly configured single suture patterns
- •Understanding the dual compartment anatomy is critical for surgeons planning reinnervation procedures or neuroprosthesis implantation for recurrent laryngeal neuropathy
- •The lateral compartment's superior role in increasing airway diameter may make it a priority target for surgical intervention in RLN cases
- •Knowledge of discrete motor endplate locations informs precise electrode or graft placement for functional restoration
- •PMMA augmentation of laryngoplasty may reduce early post-operative abduction loss by mechanically stabilizing the cricoarytenoid joint against physiological airflow forces
- •This technique could improve long-term outcomes in horses undergoing laryngoplasty for recurrent laryngeal neuropathy by reducing suture strain
- •Further in vivo studies are needed before clinical adoption, but the biomechanical evidence supports investigation as an adjunctive surgical technique
- •Both suture placement techniques achieve similar mechanical strength in vitro, so choice may depend on surgeon preference and equipment availability
- •Bone trocar pre-drilling appears to produce more predictable failure patterns with reduced fissure formation, potentially lowering long-term complications from suture pullout
- •Results suggest bone trocar technique may be preferable for laryngoplasty in clinical practice to minimize cartilage damage, though clinical validation is needed
- •RLN presents predominantly as left-sided paralysis in Thoroughbreds and performance horses; suspect this diagnosis in athletic horses with exercise-induced respiratory noise even if exercise intolerance has not yet developed
- •Bilateral laryngeal paralysis is rare in RLN but common in ponies with non-idiopathic causes—investigate hepatic disease and consider anaesthetic complications in these cases
- •Intercurrent respiratory disease affects 40% of RLN cases, so always perform complete upper and lower airway assessment rather than assuming a single diagnosis explains clinical signs
- •Current suture-based laryngoplasties fail at relatively low forces (~56 N), suggesting potential for inadequate durability in clinical use
- •A cable prosthesis design shows 4–6 fold greater resistance to failure forces in cadaveric testing, warranting further development
- •This is early-stage device research; clinical efficacy and long-term safety in living horses remain to be established before adoption
Key Research Findings
Resting endoscopy demonstrated 74.4% sensitivity and 95.1% specificity for predicting abnormal laryngeal function at exercise
Only 3.5% of horses with grade 1 and 11.9% with grade 2 resting laryngeal function showed abnormal function at exercise
Among horses with grade 3 resting function, 57.6% demonstrated complete or partial paralysis (grade C) at exercise
Negative predictive value was 90.5%, indicating good reliability for ruling out disease when resting endoscopy appears normal
Modified laryngoplasty resulted in fibrous ankylosis of the cricoarytenoid joint, confirmed histologically in all treated horses
Loss of arytenoid abduction at 3 months was significantly greater in control laryngoplasty (n=3) versus modified procedure (n=5)
Translaryngeal impedance was significantly lower in the modified laryngoplasty group compared to control, indicating better airway patency
Intact sutures maintained lower impedance compared to cut sutures, demonstrating the stabilizing effect of the surgical modification
Yearling laryngeal function ≥grade II.2 had 4.61 times higher odds of requiring prosthetic laryngoplasty compared to <grade II.2
Yearling laryngeal function ≥grade III.1 had 10.7 times higher odds of requiring prosthetic laryngoplasty compared to <grade III.1
Three-quarters of the prosthetic laryngoplasty group had ≤grade II.2 yearling laryngeal function, indicating post-sale deterioration in laryngeal function was common
Risk of requiring prosthetic laryngoplasty increased progressively from grade II.2 onwards, with grades III.2 and above showing dramatically elevated odds ratios
EIPH was identified in 26% of competitive draft pulling horses
RLH was present in 32% of the study population
Tracheal mucus was found in 82% of participating draft horses
Evidence Base
Meta-analysis evaluating resting laryngeal endoscopy as a diagnostic tool for recurrent laryngeal neuropathy in the equine athlete.
Elliott S, Cheetham J (2019) — Equine veterinary journal
Systematic Review
A modified laryngoplasty approach promoting ankylosis of the cricoarytenoid joint.
Parente Eric J, Birks Eric K, Habecker Perry (2011) — Veterinary surgery : VS
RCT
Yearling laryngeal function in Thoroughbreds that underwent a laryngoplasty differs from controls.
Hardwick Josephine L, Ahern Benjamin J, Crawford Kylie L et al. (2025) — Equine veterinary journal
Cohort Study
Prevalence of Exercise-Induced Pulmonary Hemorrhage, Tracheal Mucus and Recurrent Laryngeal Neuropathy in Competitive Draft Pulling Horses.
Burns Jennifer J, MacMillan Kathleen M, John Emily (2023) — Journal of equine veterinary science
Cohort Study
Abnormalities detected at pre-purchase examination of National Hunt racehorses presented at sale.
Barrett E, Arkins S (2020) — Equine veterinary journal
Cohort Study
Using quarterly earnings to assess racing performance in 70 thoroughbreds after modified laryngoplasty for treatment of recurrent laryngeal neuropathy.
Aceto Helen, Parente Eric J (2012) — Veterinary surgery : VS
Cohort Study
Relative prevalence of upper respiratory tract obstructive disorders in two breeds of harness racehorses (185 cases: 1998-2006).
Strand E, Fjordbakk C T, Sundberg K et al. (2012) — Equine veterinary journal
Cohort Study
Association of treadmill upper airway endoscopic evaluation with results of ultrasonography and resting upper airway endoscopic evaluation.
Garrett K S, Woodie J B, Embertson R M (2011) — Equine veterinary journal
Cohort Study
Exercising upper respiratory videoendoscopic evaluation of 100 nonracing performance horses with abnormal respiratory noise and/or poor performance.
Davidson E J, Martin B B, Boston R C et al. (2011) — Equine veterinary journal
Cohort Study
Variability of resting endoscopic grading for assessment of recurrent laryngeal neuropathy in horses.
Perkins J D, Salz R O, Schumacher J et al. (2009) — Equine veterinary journal
Cohort Study
Acute phase response to surgery of varying intensity in horses: a preliminary study.
Jacobsen Stine, Nielsen Jon Vedding, Kjelgaard-Hansen Mads et al. (2009) — Veterinary surgery : VS
Cohort Study
Race performance after laryngoplasty and ventriculocordectomy in National Hunt racehorses.
Barakzai Safia Z, Boden Lisa A, Dixon Padraic M (2009) — Veterinary surgery : VS
Cohort Study
The effect of recurrent laryngeal neurectomy in conjunction with laryngoplasty and unilateral ventriculocordectomy in thoroughbred racehorses.
Davenport C L, Tulleners E P, Parente E J (2001) — Veterinary surgery : VS
Cohort Study
The effect of cyanoacrylate on knot elongation in three sutures used for prosthetic laryngoplasty in the horse.
Watkins Amanda R, Ford Matt, van Eps Andrew W et al. (2023) — Veterinary surgery : VS
Case Report
Ex vivo study of vagal branches at risk for iatrogenic injury during laryngoplasty in horses.
Pisano Simone R R, Stoffel Michael H, Bodó Gábor (2021) — Veterinary surgery : VS
Case Report
Outcomes of horses treated with removal of a laryngoplasty prosthesis.
Fitzharris Laura E, Lane J Geoffrey, Allen Kate J (2019) — Veterinary surgery : VS
Case Report
Transcutaneous Ultrasonography Is a Feasible Method for Characterizing the Cricoarytenoideus Dorsalis Muscle in Horses.
Satoh Masato, Higuchi Tohru, Inoue Satoshi et al. (2019) — Journal of equine veterinary science
Case Report
Modified first or second cervical nerve transplantation technique for the treatment of recurrent laryngeal neuropathy in horses.
Rossignol F, Brandenberger O, Perkins J D et al. (2018) — Equine veterinary journal
Case Report
Unilateral cervical plexus block for prosthetic laryngoplasty in the standing horse.
Campoy L, Morris T B, Ducharme N G et al. (2018) — Equine veterinary journal
Case Report
Dynamic respiratory endoscopic findings pre- and post laryngoplasty in Thoroughbred racehorses.
Leutton J L, Lumsden J M (2015) — Equine veterinary journal
Case Report
Show 36 more references
Upper esophageal incompetence in five horses after prosthetic laryngoplasty.
Barakzai Safia Z, Dixon Paddy M, Hawkes Claire S et al. (2015) — Veterinary surgery : VS
Case Report
Maintenance of arytenoid abduction following carbon dioxide laser debridement of the articular cartilage and joint capsule of the cricoarytenoid joint combined with prosthetic laryngoplasty in horses: an in vivo and in vitro study.
Hawkins J F, Couetil L, Miller M A (2014) — Veterinary journal (London, England : 1997)
Case Report
Long-term maintenance of arytenoid cartilage abduction and stability during exercise after laryngoplasty in 33 horses.
Barnett Timothy P, O'Leary John Mark, Parkin Timothy D H et al. (2013) — Veterinary surgery : VS
Case Report
Effect of age and prostheses location on rima glottidis area in equine cadaveric larynges.
Bischofberger Andrea S, Hadidane Ines, Wereszka Marta M et al. (2013) — Veterinary surgery : VS
Case Report
Optimal tension, position, and number of prostheses required for maximum rima glottidis area after laryngoplasty.
Bischofberger Andrea S, Wereszka Marta M, Hadidane Ines et al. (2013) — Veterinary surgery : VS
Case Report
Clinicopathologic observations on laryngoplasty failure in a horse.
Hardcastle Michael Robert, Pauwels Frederik Ekhart Theo, Collett Mark Grey (2012) — Veterinary surgery : VS
Case Report
In vitro effect of ventriculocordectomy before laryngoplasty on abduction of the equine arytenoid cartilage.
Perkins Justin D, Meighan Hazel, Windley Zoë et al. (2011) — Veterinary surgery : VS
Case Report
Postoperative race performance is not correlated with degree of surgical abduction after laryngoplasty in National Hunt Thoroughbred racehorses.
Barakzai Safia Z, Boden Lisa A, Dixon Padraic M (2009) — Veterinary surgery : VS
Case Report
Myosin heavy chain composition in normal and atrophic equine laryngeal muscle.
Adreani C M, Li Z B, Lehar M et al. (2006) — Veterinary pathology
Case Report
Standing surgical removal of inspissated guttural pouch exudate (chondroids) in ten horses.
Perkins Justin D, Schumacher Jim, Kelly Ger et al. (2006) — Veterinary surgery : VS
Case Report
Effects of unilateral laser-assisted ventriculocordectomy in horses with laryngeal hemiplegia.
Robinson P, Derksen F J, Stick J A et al. (2006) — Equine veterinary journal
Case Report
Upper airway dysfunction associated with collapse of the apex of the corniculate process of the left arytenoid cartilage during exercise in 15 horses.
Dart Andrew J, Dowling Bradley A, Smith Christine L (2005) — Veterinary surgery : VS
Case Report
Biomechanical testing of three constructs for prosthetic laryngoplasty in horses demonstrates advantages of differing metallic implants in the arytenoid cartilage.
Ysebaert Machiel P, Johnson James, Marie Ulrika et al. (2026) — Veterinary surgery : VS
Expert Opinion
Equine laryngoplasty: Effects of three anchoring techniques in the muscular process and three positions for suture implantation in the cricoid cartilage.
Maire Ulrika, Ducharme Norm G, Rossignol Anthony et al. (2024) — Veterinary surgery : VS
Expert Opinion
Comparison of treatments for equine laryngeal hemiplegia using computational fluid dynamic analysis in an equine head model.
Tucker Michelle L, Wilson David G, Bergstrom Donald J et al. (2024) — Frontiers in veterinary science
Expert Opinion
A first step towards objective grading of equine laryngeal function.
Hardwick Josephine, Ahern Benjamin, Franklin Samantha (2024) — Veterinary journal (London, England : 1997)
Expert Opinion
Variations in the application of equine prosthetic laryngoplasty: A survey of 128 equine surgeons.
Byrne Christian A, Hotchkiss Joel W, Barakzai Safia Z (2023) — Veterinary surgery : VS
Expert Opinion
Evaluation of Overground Endoscopy Findings in Colombian Criollo Paso Horses.
Joó Kinga, Duque Betancourt Diego, Vasquez Marin Tomas et al. (2021) — Journal of equine veterinary science
Expert Opinion
In vitro evaluation of the effect of a prototype dynamic laryngoplasty system on arytenoid abduction.
Ahern Benjamin J, Lim Yee-Wei, van Eps Andrew et al. (2018) — Veterinary surgery : VS
Expert Opinion
Anatomy of the vestibulum esophagi and surgical implications during prosthetic laryngoplasty in horses.
Brandenberger Olivier, Martens Ann, Robert Céline et al. (2018) — Veterinary surgery : VS
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In vitro comparison of 3 techniques of prosthesis attachment to the muscular process of the equine arytenoid cartilage.
Ahern Benjamin J, Van Eps Andrew W, Boston Raymond C et al. (2017) — Veterinary surgery : VS
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Ex vivo biomechanical stability of 5 cricoid-suture constructs for equine laryngoplasty.
Brandenberger Olivier, Rossignol Fabrice, Perkins Justin D et al. (2017) — Veterinary surgery : VS
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Genetics of upper and lower airway diseases in the horse.
Gerber V, Tessier C, Marti E (2015) — Equine veterinary journal
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Racing performance following prosthetic laryngoplasty using a polyurethane prosthesis combined with a laser-assisted ventriculocordectomy for treatment of recurrent laryngeal neuropathy in 78 Thoroughbred racehorses.
Raffetto J A, Wearn J G, Fischer A T (2015) — Equine veterinary journal
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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.
McClellan Nathaniel R, Santschi Elizabeth M, Hurcombe Samuel D A et al. (2014) — Veterinary surgery : VS
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Anatomic and neuromuscular characterisation of the equine cricothyroid muscle.
Reesink H L, Hermanson J W, Cheetham J et al. (2013) — Equine veterinary journal
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In vitro mechanical testing of an alternate laryngoplasty system (ALPS) for horses.
Ahern Benjamin J, Boston Raymond C, Parente Eric J (2012) — Veterinary surgery : VS
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Association of owner-reported noise with findings during dynamic respiratory endoscopy in Thoroughbred racehorses.
Witte S H P, Witte T H, Harriss F et al. (2011) — Equine veterinary journal
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Considerations for pacing of the cricoarytenoid dorsalis muscle by neuroprosthesis in horses.
Ducharme N G, Cheetham J, Sanders I et al. (2010) — Equine veterinary journal
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In vitro model for testing novel implants for equine laryngoplasty.
Cheetham Jon, Witte Thomas H, Soderholm Leo V et al. (2008) — Veterinary surgery : VS
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Biomechanical comparison of six suture configurations using a large diameter polyester prosthesis in the muscular process of the equine arytenoid cartilage.
Kelly Jenny R, Carmalt James, Hendrick Steven et al. (2008) — Veterinary surgery : VS
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Neuroanatomy of the equine dorsal cricoarytenoid muscle: surgical implications.
Cheetham J, Radcliffe C R, Ducharme N G et al. (2008) — Equine veterinary journal
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Intra-articular stabilisation of the equine cricoarytenoid joint.
Cheetham J, Witte T H, Rawlinson J J et al. (2008) — Equine veterinary journal
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In vitro comparison of two techniques for suture prosthesis placement in the muscular process of the equine arytenoid cartilage.
Rossignol Fabrice, Perrin Roland, Desbrosse Francis et al. (2006) — Veterinary surgery : VS
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Laryngeal paralysis: a study of 375 cases in a mixed-breed population of horses.
Dixon P M, McGorum B C, Railton D I et al. (2001) — Equine veterinary journal
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In vitro evaluation of a novel prosthesis for laryngoplasty of horses with recurrent laryngeal neuropathy.
Schumacher J, Wilson A M, Pardoe C et al. (2000) — Equine veterinary journal
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