Arytenoid dislocation: An analysis of the contemporary literature

Incidence and Risk Factors of Arytenoid Dislocation Following Endotracheal Intubation: A Systematic Review and Meta-Analysis

Endotracheal intubation carries risks, including arytenoid dislocation (AD), a rare but severe complication. Due to small sample sizes, the incidence of AD varies considerably among studies. Proposed risk factors for AD include difficult intubation, prolonged intubation, certain surgeries, patient positioning, female sex, and BMI. This review aims to investigate the incidence of AD and explore the various predisposing risk factors. We retrieved relevant studies up to April 2024 from PubMed, Scopus, Web of Science, and the Cochrane Library. Using OpenMeta v5.26.14 software (Institute for Clinical Research and Health Policy Studies at Tufts Medical Center, Boston, USA), we pooled AD incidence rates from individual studies. Other outcomes, reported in fewer studies and thus not suitable for meta-analysis, were synthesized manually. Study selection yielded 16 eligible articles. A random-effects model analysis of nine studies found a significant AD incidence rate of 0.093% (confidence interval (CI): 0.045% to 0.14%), but the results were highly heterogeneous (I2 = 91%). Older age was associated with prolonged hoarseness, while younger age and female sex increased the risk of AD. Additionally, AD risk factors included taller stature, higher BMI, specific surgeries, esophageal instrumentation, prolonged procedure durations, head-neck movement, and inexperienced intubators. However, intubation with a stylet reduced the AD risk. AD post-endotracheal intubation is rare (incidence: 0.09%), with potential underdiagnosis in larger datasets. Many risk factors may contribute to the condition, but the small number of studies per risk factor limits the ability to draw robust conclusions. Subjective diagnoses and retrospective studies further restrict comprehensive understanding. Further research is needed to explore AD risk factors effectively.

A Novel Five-Step Reduction Technique of Arytenoid Dislocation

The article reported a novel reduction device and standardized reduction technique for patients with arytenoid dislocation. The results showed that this reduction technique has been excellent in helping patients with arytenoid dislocation. Laryngoscope, 134:1744-1748, 2024.

Modified Laryngeal Forceps for Arytenoid Cartilage Dislocation Caused by Endotracheal Intubation: A Retrospective Case-Control Pilot Study

Background: Arytenoid cartilage dislocation is considered as a rare laryngeal injury and closed reduction is commonly used as the first choice for the arytenoid dislocation. However, the tools of closed reduction vary, and there is no dedicated tool for closed reduction, and the treatment outcome varies from person to person. This study compared the treatment outcome of the modified laryngeal forceps and traditional laryngeal forceps. Material and Methods: This study conformed to the strengthening the reporting of observational studies in epidemiology guidelines regarding retrospective studies. From May 2021 to February 2023, the records of 28 patients with arytenoid cartilage dislocation caused by endotracheal intubation were reviewed. They were divided into the traditional group (n = 14) and the modified group (n = 14) by gender. Indirect or direct laryngoscopy, video stroboscopy, high-resolution computed tomography, and cricoarytenoid joint 3-dimensional reconstruction were used to evaluate arytenoid position and motion. Clinical characteristics, voice function, procedural skill, and treatment outcome for each case were recorded. Results: Each patient was diagnosed with arytenoid dislocation caused by endotracheal intubation. There was no significant difference in the treatment outcome between the traditional group and the modified group (P > .05). However, the median time interval between closed reduction and the return of normal voice in the traditional group was 31.08 ± 10.56 days, which was significantly longer than the median time of 17.92 ± 3.83 days in the modified group (P < .05). Conclusion: Closed reduction with the modified laryngeal forceps under local anesthesia is an effective and safe procedure. Compared with traditional laryngeal forceps, the modified laryngeal forceps can shorten the treatment duration.

Hoarseness and arytenoid dislocation: A rare complication after facial bony contouring surgery

BACKGROUND

Arytenoid dislocation is a rare complication after endotracheal intubation and may result in permanent hoarseness, which cannot be tolerated during cosmetic surgeries, such as facial bony contouring surgery. This study aimed to identify the clinical characteristics of this patient subgroup and share the process of diagnosis and treatment.

METHODS

We retrospectively collected the medical records of patients who underwent facial bony contouring surgery under general anesthesia with endotracheal intubation from September 2017 to July 2022. We divided the patients into a nondislocation group and a dislocation group. Demographic, anesthetic, and surgical characteristics were collected and compared.

RESULTS

441 patients were enrolled, and 5 (1.1%) were diagnosed with arytenoid dislocation. The patients in the dislocation group were more likely to be intubated with the video laryngoscope (P = 0.049), and head-neck movement during surgery may predispose patients to arytenoid dislocation (P = 0.019). The patients in the dislocation group were diagnosed around 5-37 days after surgery. Three of them regained their normal voice after close reduction, and two recovered with speech therapy.

CONCLUSION

Arytenoid dislocation may result from multiple factors instead of one high-risk factor. Head-neck movement, the skills and experience of anesthetists, the time of intubation, and the use of intubation tools may all predispose patients to arytenoid dislocation. To acquire timely diagnosis and treatment, patients should be fully informed of this complication before surgery and observed closely afterward. Any postoperative voice or laryngeal symptoms lasting more than 7 days need a specialist evaluation.

Effects of Superomedial Partial Arytenoidectomy on Incomplete Posterior Glottal Closure Caused by Arytenoid Positional Asymmetry in Excised Human Larynges

OBJECTIVES

To analyze the effects that arytenoid positional asymmetry has on posterior glottic closure and to determine whether superomedial partial arytenoidectomy (SPA) can provide a benefit in cases of such asymmetry.

METHODS

In this experimental study, we evaluated posterior glottic closure in 10 larynges freshly excised from human cadavers, measuring the distance between the vocal processes before and after artificially simulated positional asymmetry of the arytenoid cartilages. We then performed SPA, after which we again measured the distance between the vocal processes.

RESULTS

In all of the larynges studied, the posterior glottic closure went from complete to incomplete after simulation of arytenoid positional asymmetry, the median distance observed between the vocal processes being 1.74mm (interquartile range 0.22). The SPA performed after arytenoid asymmetry caused the posterior glottic closure to return from incomplete to complete in all of the larynges studied.

CONCLUSION

Our results suggest that arytenoid positional asymmetry impairs posterior glottic closure and that SPA improves posterior glottic closure in such cases of arytenoid asymmetry.

Risk factors of arytenoid dislocation after endotracheal intubation: A propensity-matched analysis

Objective

Arytenoid dislocation (AD) after general anesthesia with endotracheal intubation (EI) is an iatrogenic injury that impairs patient function and requires reduction. We aimed to investigate the risk factors of AD following EI.

Methods

This retrospective case-control study involved surgical adults who received EI for general anesthesia at a single institution from June 2010 to June 2020. Cases included all the patients who had AD. We used a ratio of 1:5 to identify patients in the propensity-matched control group.

Results

Multivariate analysis of 49 cases with AD and 245 controls without AD demonstrated that the use of a nasogastric (NG) tube (odds ratio [OR], 23.9; 95% confidence interval [CI], 6.8-84.1), undergoing abdominal surgery (OR, 3.7; 95% CI, 1.2-11.9), and an operative time longer than 3 h (OR, 5.2; 95% CI, 2.1-12.9) were risk factors for AD. We did not find significant independent associations between AD and 40 years or older age, gender, body mass index, whether a laryngeal mask airway was used, endotracheal tube size, and EI performers' experience.

Conclusion

The use of an NG tube, abdominal surgery, and longer operative time were risk factors for AD. Among these, the NG tube application showed a strong association with AD. Preventive measures of informing the patients of the increased risk and providing high-level patient monitoring can reduce the incidence of AD.

Level of Evidence

III.

Laryngeal complications after endotracheal intubation and prone positioning in patients with coronavirus disease 2019

Objectives

Laryngeal complications have been reported after endotracheal intubation and prone positioning in patients with critical coronavirus disease 2019 (COVID-19), but their association is unclear. In this study, we investigated the rate of laryngeal complications in patients with COVID-19 compared to an alternative condition (control group).

Methods

We retrospectively analyzed the data of 40 patients who underwent endotracheal intubation for either COVID-19 or an alternative condition (control group). Data on age, sex, body mass index (BMI), cardiovascular disease (CVD) risk factors, use of prone therapy, duration of endotracheal intubation, and duration from extubation/tracheostomy to laryngeal evaluation were collected from medical records.

Results

There were no significant differences in BMI, frequency of CVD risk factors, duration of endotracheal intubation, or duration from extubation/tracheostomy to laryngeal evaluation between the two groups. In the COVID-19 group, all patients adopted the prone position. In comparison, only one patient in the control group adopted the prone position. Significant differences were observed between the two groups regarding the incidence of vocal fold immobility and laryngeal granuloma.

Conclusion

Laryngeal complications were more common in the COVID-19 group than in the control group. Prone positioning may be a risk factor for these complications.

Level of Evidence

4.

Laryngeal Dysfunction in Acute Organophosphorus and Carbamate Poisoning

Background

Organophosphorus (OP) and carbamate pesticides are widely used for crop protection. We describe the spectrum of laryngeal abnormalities in patients admitted to the intensive care unit (ICU) with acute OP and carbamate poisoning as there is limited information on it.

Materials and methods

Consecutive patients admitted to the ICU with acute OP and carbamate poisoning over 20 months (December 2014–July 2016) were recruited. Patients were followed up post-discharge if they had undergone tracheostomy or developed hoarseness of voice or stridor following extubation. Asymptomatic individuals who consented underwent laryngoscopy after ICU discharge. The primary outcome was the development of laryngeal dysfunction. Other outcomes included length of stay, need for ventilation, mortality, tracheostomy, and time to decannulation of tracheostomy.

Results

Of the 136 patients recruited, 71 (52%) underwent laryngoscopy. The overall mortality rate was 9.6%. Of the 71 patients who underwent laryngoscopy, 18 had abnormal findings, which included unilateral or bilateral vocal cord paresis or palsy (n = 14) and/or aspiration (n = 9), subglottic stenosis (n = 1), tracheal stenosis (n = 1), or arytenoid granuloma (n = 1). Laryngeal dysfunction was associated with the ingestion of a dimethyl OP compound (p = 0.04) and quantum consumed (p <0.001). Patients with laryngeal dysfunction had significantly (p = 0.004) longer hospital stay (19.1 ± 10.7 vs 11.8 ± 8.3 days).

Conclusion

Laryngeal dysfunction is not uncommon in OP and carbamate poisoning and is associated with the ingestion of larger quantity of a dimethyl OP compound and longer hospital stay. Otorhinolaryngologists could be involved early to help identify these abnormalities and initiate an appropriate treatment to ensure a functional voice and good airway.

How to cite this article

Mani GS, Mathews SS, Victor P, Peter JV, Yadav B, Albert RRA. Laryngeal Dysfunction in Acute Organophosphorus and Carbamate Poisoning. Indian J Crit Care Med 2022;26(2):167–173.

Cricoarytenoid subluxation presenting as vocal cord palsy following endotracheal intubation – A case report

Airway interventions commonly present with self-limiting throat pain and hoarseness of voice. Persistent hoarseness is rare and should be evaluated for serious complications. Cricoarytenoid injuries may present as vocal cord palsies which need careful evaluation. We encountered a case of intubation-related cricoarytenoid subluxation in a 49-year-old diabetic female with a past history of pulmonary tuberculosis was planned for a modified radical mastectomy after a course of neoadjuvant chemotherapy. During intubation by a third-year resident, Cormack Lehane's grade was 3, and bougie-guided railroading of 7 mm endotracheal tube was done blindly. The patient developed haemoptysis and desaturation following intubation and was on ventilator support for 24 hours. Following extubation, the patient had throat pain and hoarseness in voice for more than 2 days. Fibreoptic laryngoscopy revealed right vocal cord palsy. A detailed evaluation revealed right cricoarytenoid subluxation which was treated successfully by closed reduction after 1 week. Cricoarytenoid subluxation, though rare is a serious complication after interventional airway procedures. According to the literature, unfavourable intubating conditions, predisposing patient factors and inadequate experience of the anaesthesiologist are the major contributors to this complication. Injury may produce submucosal haemorrhage and haemarthrosis, which cause adhesions and scarring leading to fixing of vocal cord in abnormal position and permanent disability. Early diagnosis by fibreoptic laryngoscopy and CT imaging and prompt interventions like closed reduction or laryngoplasty should be done to restore vocal cord function.

Head-neck movement may predispose to the development of arytenoid dislocation in the intubated patient: a 5-year retrospective single-center study

Background

Arytenoid dislocation is a rare laryngeal injury that may follow endotracheal intubation. We aimed to determine the incidence and risk factors for arytenoid dislocation after surgery under general anaesthesia.

Methods

We reviewed the medical records of patients who underwent operation under general anaesthesia with endotracheal intubation from January 2014 to December 2018. Patients were divided into the non-dislocation and dislocation groups depending on the presence or absence of arytenoid dislocation. Patient, anaesthetic, and surgical factors associated with arytenoid dislocation were determined using Poisson regression analysis.

Results

Among the 25,538 patients enrolled, 33 (0.13%) had arytenoid dislocation, with higher incidence after anterior neck and brain surgery. Patients in the dislocation group were younger (52.6 ± 14.4 vs 58.2 ± 14.2 yrs, P = 0.025), more likely to be female (78.8 vs 56.5%, P = 0.014), and more likely to be intubated by a first-year anaesthesia resident (33.3 vs 18.5%, P = 0.048) compared to those in the non-dislocation group. Patient positions during surgery were significantly different between the groups (P = 0.000). Multivariable Poisson regression identified head-neck positioning (incidence rate ratio [IRR], 3.10; 95% confidence interval [CI], 1.50–6.25, P = 0.002), endotracheal intubation by a first-year anaesthesia resident (IRR, 2.30; 95% CI, 1.07–4.64, P = 0.024), and female (IRR, 3.05; 95% CI, 1.38–7.73, P = 0.010) as risk factors for arytenoid dislocation.

Conclusion

This study showed that the incidence of arytenoid dislocation was 0.13%, and that head-neck positioning during surgery, less anaesthetist experience, and female were significantly associated with arytenoid dislocation in patients who underwent surgeries under general anaesthesia with endotracheal intubation.

Characteristics, natural evolution and surgical treatment outcomes of unilateral laryngeal paralysis versus ankylosis: A longitudinal cohort study

AIMS

Although unilateral laryngeal immobility (ULI) can results from paralysis or ankylosis of the cricoarytenoid joint, no comparative study exists to date. Aim of this study was to compare clinical features, aetiologies, spontaneous recovery and evolution after surgical treatment of ULI according to its mechanism.

METHODOLOGY

Longitudinal observational cohort study between 1992 and 2017 in a tertiary care referral centre and university teaching hospital. All adult patients with isolated ULI were included. Presenting symptoms and demographic data were recorded at baseline. During follow-up, natural recovery and, if a surgical treatment was performed, treatment failure rate were noted.

RESULTS

994 patients were included, 56.4% of male and with a mean age of 58 years. Overall, 91% had paralysis and 9% had ankylosis. Dysphonia was the main symptom in both groups (>96%). Dyspnoea was more frequent in patients with ankylosis (26.1% vs 4.2% in those with paralysis) whereas dysphagia was more frequent in those with paralysis (31.1% vs 20% in those with ankylosis). With a mean follow-up of 2.3 years (±5.1), spontaneous recovery did not differ according to ULI's aetiology (hazard ratio 1.43, 95% confidence interval 0.85-2.40). Overall, 37.1% underwent a surgical treatment, and paralysis was associated with a lower odd of treatment failure (hazard ratio 0.27, 95% confidence interval 0.10-0.70) over a mean follow-up of 3.1 years (±4.1).

CONCLUSION

ULI resulting from paralysis or ankylosis differ in their symptoms and responses to surgical treatment, whereas natural evolution was similar.

Current management of arytenoid sub-luxation and dislocation

PURPOSE

To review the current management of arytenoid subluxation/dislocation (AS/AD) focusing on diagnostic, therapeutic, and prognostic controversies.

METHODS

The international literature of the last 20 years has been considered. After the application of inclusion criteria, 20 studies were selected (471 AS/AD cases in total).

RESULTS

All the included investigations were retrospective case series. AS/AD was often iatrogenic occurring at least in 0.01% of patients undergone endo-tracheal intubation. The most common symptom was persistent hoarseness. The diagnosis was made by video-laryngoscopy and neck computed tomography in most reports, while some used also laryngeal electromyography. Laryngeal electromyography was fundamental to rule out unilateral vocal fold paralysis, the main differential diagnosis. The surgical relocation of AS/AD under general or local anesthesia was achieved in about 80% of patients.

CONCLUSION

AS/AD is a mechanical disorder of the larynx that can be successfully treated if promptly diagnosed. Clinical trials and multi-centric studies are necessary to set management guidelines.

Analysis and Temporal Evolution of Extubation Parameters for Patients Undergoing Single-Stage Circumferential Cervical Spine Surgery

Objective

Airway obstruction after postoperative extubation is a dreaded but uncommon complication in patients undergoing circumferential cervical spine surgery (CCSS). The cuff leak test (CLT) has been utilized to assess air leak around the endotracheal tube which may reflect airway swelling. In this prospective observational study, we analyze the temporal evolution of CLT and perioperative factors that may influence it.

Methods

Twenty patients undergoing single-stage CCSS were managed according to our extubation protocol. Patients were maintained intubated overnight following surgery. They were extubated if a CLT > 200 mL and both intensive care unit (ICU) and Neurosurgery teams agreed that it was safe. Patients extubated in the first postoperative day (8 of 20) comprised the early group, and the remaining patients (12 of 20) the delayed group. Patient and operative data were analyzed as a single group and comparing both groups.

Results

The main indication for surgery was cervical deformity. Median number of levels fused was 5 anteriorly (range, 1–6) and 6 (range, 1–13) posteriorly. Patients were kept intubated for an average of 73.6 hours (range, 26–222 hours) and stayed in the ICU for 119.1 hours (range, 36–360 hours). There were 4 failed extubations and 3 patients (15%) required a tracheostomy. Patient profiles between both groups were very similar across most patient variables but differed significantly regarding infraglottic luminal area (p < 0.05). Patients with larger preoperative cuff leak values tended to have a shorter intubation period (p=0.053).

Conclusion

This study objectively demonstrates the difficulties in airway management following CCSS and provides useful insight for preoperative planning and counseling. Local anatomic factors influence airway outcome more than operative factors. The study format does not allow for testing of interventions but we suggest that patients with favorable anatomy (larger infraglottic luminal area) may benefit from a less strict airway management protocol.

Regularity of voice recovery and arytenoid motion after closed reduction in patients with arytenoid dislocation: a self-controlled clinical study

Background: Closed reduction is an effective treatment for arytenoid dislocation. The treatment is usually given more than once to obtain normal voice. However, when to perform the next closed reduction remains controversial.Objective: This study aimed to observe the regularity of the voice recovery and the arytenoid motion in patients with arytenoid dislocation after closed reduction.Material and methods: Thirty-one patients were recruited from September 2017 to April 2019. Results of their clinical data were reviewed retrospectively.Results: Among the thirty-one patients, their VHI scores, F0, jitter%, shimmer%, glottal-to-noise excitation %(GNE), maximum phonation time (MPT) and GRBAS Scale (G, R, B, A) improved significantly (p < .05), but there was no statistically significant difference for GRBAS Scale (S) (p>.05). The duration between last closed reduction and the restoring normal voice ranged from 1-8 days, with a mean of 4.65 ± 0.57 days, at the same time the glottis was completely closed.Conclusions and significance: Closed reduction for patients with arytenoid dislocation is an effective procedure. A time window between 4.08th and 5.22th day (at a confidence level of 95%) after the last closed reduction was identified to be critical for voice recovery.

Treatment Outcomes of Arytenoid Dislocation by Closed Reduction: A Multidimensional Evaluation

OBJECTIVE

This study aimed to investigate the treatment outcomes of arytenoid dislocation by a multidimensional evaluation.

METHODS

From April 2010 to May 2018, the records of 57 patients with a history of arytenoid dislocation were reviewed. All the patients were treated with closed reduction under local anesthesia. Arytenoid motion, grade, roughness, breathiness, asthenia, strain, maximum phonation time, self-assessed Voice Handicap Index, and acoustic voice analysis were used to evaluate the clinical outcomes.

RESULTS

Following closed reduction, 57 patients were divided into "recovered" (n = 24), "improved" (n = 15), and "ineffective" (n = 18) groups. There were no major complications resulting from surgical intervention.

CONCLUSION

Closed reduction under local anesthesia continues to be an effective and well-tolerated method for treating arytenoid dislocation. The trichotomy of the treatment results of arytenoid dislocation by a multidimensional evaluation may be more accurate to evaluate the results of arytenoid dislocation.

A Rare Complication Following Anesthesia: Arytenoid Dislocation During Orthognathic Surgery

PURPOSE

Arytenoid dislocation is a rare complication after tracheal intubation, and there are no published studies reporting on arytenoid dislocation during orthognathic surgery. The frequency of this phenomenon and the results of therapy were evaluated in this study.

MATERIALS AND METHODS

Three of 5,032 patients who underwent orthognathic surgery during an 11-year period had a postoperative arytenoid dislocation. Closed reduction was used in these 3 patients. To check the therapeutic effect, arytenoid dislocation symptoms were recorded and acoustic analysis was performed before reduction, immediately after reduction, and 1, 2, and 4 weeks after reduction.

RESULTS

The incidence of arytenoid dislocation in orthognathic surgery was 0.0596%. The symptoms of 2 patients showed marked improvement 2 weeks after reduction with voice recovery and resolution of odynophagia. The symptoms of the other patient showed marked improvement 4 weeks after reduction. The treatment effects for all 3 patients were satisfactory.

CONCLUSION

Arytenoid dislocation must be considered in cases of prolonged hoarseness after orthognathic surgery. Examination should be carried out as soon as possible, which can hasten the treatment of arytenoid dislocation and achieve a good outcome.

Quantitative Measurement of the Three-dimensional Structure of the Vocal Folds and Its Application in Identifying the Type of Cricoarytenoid Joint Dislocation

OBJECTIVE

The objective of this study was to quantitatively measure the three-dimensional (3D) structure of the vocal folds in normal subjects and in patients with different types of cricoarytenoid dislocation. We will analyze differences in parameters between the groups and also determine if any morphologic parameters possess utility in distinguishing the type and the degree of cricoarytenoid dislocation.

STUDY DESIGN

This retrospective study was conducted using university hospital data.

METHODS

Subjects' larynges were scanned using dual-source computed tomography (CT). The normal subjects were divided into deep-inhalation and phonation groups, and patients with cricoarytenoid joint dislocation were divided into anterior-dislocation and posterior-dislocation groups. Membranous vocal fold length and width were measured directly on the thin-section CT images. Vocal fold and airway 3D models were constructed using Mimics software and used in combination to measure vocal fold thickness, subglottal convergence angle, and oblique angle of the vocal folds.

RESULTS

The phonation group displayed a greater vocal fold width, greater oblique angle, thinner vocal folds, and a smaller subglottal convergence angle than those of the deep-inhalation group (P < 0.05). The anterior-dislocation group displayed a smaller oblique angle and subglottal convergence angle than the posterior-dislocation group (P < 0.05).

CONCLUSIONS

The 3D structure of the vocal folds during deep inhalation and phonation can be accurately measured using dual-source CT and laryngeal 3D reconstruction. As the anterior-dislocation group yielded negative values for the oblique angle and the posterior-dislocation group yielded positive values, the oblique angle of the vocal folds may possess utility for distinguishing the type and for quantitatively determining the degree of cricoarytenoid dislocation.

Cardiovascular operation: A significant risk factor of arytenoid cartilage dislocation/subluxation after anesthesia

Background:

Arytenoid cartilage dislocation/subluxation is one of the rare complications following tracheal intubation, and there have been no reports about risk factors leading this complication. From our clinical experience, we have an impression that patients undergoing cardiovascular operations tend to be associated with this complication.

Aims:

We designed a large retrospective study to reveal the incidence and risk factors predicting the occurrence and to examine whether our impression is true.

Settings and Designs:

This was a retrospective study.

Methods:

We retrospectively studied 19,437 adult patients who were intubated by an anesthesiologist in our operation theater from 2002 to 2008. The tracheal intubation was performed by a resident anesthesiologist managing the patients. Only patients whose postoperative voice was disturbed more than 7 days were referred to the Department of Otorhinolaryngology-Head and Neck Surgery and examined using laryngostroboscopy by a laryngologist to diagnose arytenoid cartilage dislocation/subluxation. We evaluated age, sex, weight, height, duration of intubation, difficult intubation, and major cardiovascular operation as risk factors to lead this complication.

Statistical Analysis:

The data were analyzed by logistic regression analysis to assess factors for arytenoid cartilage dislocation/subluxation after univariate analyses using logistic regression analysis.

Results:

Our analysis indicated that difficult intubation (odds ratio: 12.1, P = 0.018) and cardiovascular operation (odds ratio: 9.9, P < 0.001) were significant risk factors of arytenoid cartilage dislocation/subluxation.

Conclusion:

The present study demonstrated that major cardiovascular operation is one of the significant risk factors leading this complication.

The appropriate time for closed reduction using local anesthesia in arytenoid dislocation caused by intubation: a clinical research

CONCLUSION

Closed reduction is effective and safe for the treatment of arytenoid dislocation, and the selection of an appropriate time window to perform closed reduction is crucial in achieving relatively stable treatment outcomes and short treatment duration.

OBJECTIVE

The aim of this study was to investigate whether there is an appropriate time window to perform closed reduction for unilateral arytenoid dislocation caused by intubation.

METHODS

A retrospective chart review was carried out for the cases collected from September 2014 to May 2016 at Second Affiliated Hospital of Zhejiang University, China.

RESULTS

Thirty-five patients with arytenoid dislocation were identified. Endotracheal intubation was the cause for 33 of the patients and gastric tube caused arytenoid dislocation in two patients. The patients were treated by closed reduction, and no major complications resulting from surgical intervention were observed. All patients regained normal voice and vocal fold movement after the surgery, except one patient who recovered spontaneously. As one of the most significant findings in the current study, we observed the relatively stable treatment outcomes and shortened recovery duration were obtained in the patients treated during a period between the 13th day and 26th day after arytenoid dislocation.

Closed reduction for arytenoid dislocation under local anesthesia

CONCLUSION

Closed reduction under local anesthesia continues to be an effective and well-tolerated method for treating arytenoid dislocation. Bilateral arytenoid dislocation is an uncommon occurrence, and the principles of management are the same as for unilateral dislocation.

OBJECTIVES

To evaluate the treatment outcomes of closed reduction for arytenoid dislocation under local anesthesia and to conduct an exhaustive review of the literature on bilateral arytenoid dislocation.

METHODS

Thirty-three patients with arytenoid dislocation were treated with closed reduction under local anesthesia. Arytenoid motion, GRBAS (grade, roughness, breathiness, asthenia, strain), maximum phonation time (MPT), self-assessed Voice Handicap Index (VHI), and acoustic voice analysis were used to evaluate the clinical outcomes.

RESULTS

Following closed reduction, 33 patients were divided into a 'satisfied' group (n = 26) and a 'dissatisfied' group (n = 7). In the 'satisfied' group, G, R, B, A, MPT, VHI, jitter%, shimmer%, normalized noise energy (NNE), and noise-to-harmonic ratio (NHR) were significantly improved compared with measurements taken before closed reduction (p < 0.05). The results for F0 and S score were not significantly different. In the 'dissatisfied' group, VHI, MPT, F0, and shimmer% were not significantly different 1 month after reduction. However, statistically significant change was observed in jitter% and NHR.

Clinical Characteristics of Arytenoid Dislocation After Endotracheal Intubation

OBJECTIVE

The objective of this study was to review the clinical characteristics of the arytenoid dislocations after the endotracheal intubation and to identify the factors affecting voice recovery in the arytenoid dislocation after the endotracheal intubation.

METHODS

A retrospective chart review was performed at Chonnam National University Hwasun Hospital from April 2008 to February 2014.

RESULTS

A total of 13 patients with the arytenoid dislocation were identified. The patients had undergone the endotracheal intubation for head and neck surgery (n = 7), abdominal surgery (n = 4), and orthopedic surgery (n = 2). The most common symptom was hoarseness (100%), followed by swallowing difficulty (15.4%). All of the patients with the arytenoid dislocations after the endotracheal intubation were treated by the closed reduction. All of the patients regained normal voice and vocal fold movement after the closed reduction in spite of late surgical intervention. There was no statistical significance between the Cormack-Lehane classification, expertise of anesthetist, patient's position, operation time, duration between first operation and the closed reduction, and period of voice improvement.

CONCLUSION

This study indicates that the arytenoid dislocations after the endotracheal intubation may be needed for the aggressive surgical intervention, even if the diagnosis was delayed.

Prolonged Hoarseness Caused by Arytenoid Dislocation After Anterior Cervical Corpectomy and Fusion

STUDY DESIGN

A case of arytenoid dislocation after anterior cervical corpectomy and fusion (ACCF) is reported.

OBJECTIVE

To emphasize that arytenoid dislocation could be a possible cause of prolonged hoarseness in patients after ACCF.

SUMMARY OF BACKGROUND

Prolonged hoarseness is a common postoperative complication of cervical surgeries, especially in the anterior approach. Postoperative hoarseness is usually associated with paresis of the recurrent laryngeal nerve (RLN). However, other causes such as arytenoids dislocation, which is often misdiagnosed as RLN palsy, should not be ignored either.

METHODS

We reported one case of arytenoid dislocation after ACCF and reviewed the related literatures.

RESULTS

One patient treated with ACCF experienced prolonged postoperative hoarseness. Arytenoid dislocation was confirmed by laryngoscopy examination and three-dimensional computed tomography (CT) scan. To deal with the problem, a closed reduction of cricoarytenoid joint was performed under general anesthesia. Fortunately, the motion of vocal fold became nearly back to normal after surgery and the patient recovered uneventfully. He was satisfied with the clinical outcome at the final follow-up.

CONCLUSION

Arytenoid dislocation should never be ignored in the differential diagnosis of prolonged postoperative hoarseness after ACCF. This situation can be confirmed by CT scan, vocal cord electromyography (EMG), fiberoptic laryngoscopy, or strobovideolaryngoscopy. Once the diagnosis is established, appropriate treatment should be considered immediately.

LEVEL OF EVIDENCE

3.

Severe hoarseness associated with the streamlined liner of the pharyngeal airway (SLIPATM)

Hoarseness is a common post-operative complication in patients who receive general anesthesia. In most cases, the symptoms are temporary and improve within several days. This report describes two patients with prolonged hoarseness following use of the streamlined liner of the pharyngeal airway (SLIPATM). We present the first case of a 56-year-old female patient who developed arytenoid cartilage dislocation resulting in prolonged hoarseness and dysphagia after using a SLIPA™ during a laparoscopic myomectomy. In the second case, we report on a 65-year-old male patient who was scheduled for a laparoscopic cholecystectomy. Left vocal fold paralysis or paresis resulting from recurrent laryngeal nerve injury associated with use of a SLIPA™ caused persistent hoarseness. It should be noted that recurrent laryngeal nerve injury or arytenoid cartilage dislocation are possible complications associated with use of the SLIPATM in case of persistent hoarseness.

Arytenoid cartilage dislocation from external blunt laryngeal trauma: evaluation and therapy without laryngeal electromyography

Background

Intubation trauma is the most common cause of arytenoid dislocation. The aim of this study was to investigate the diagnosis and treatment of arytenoid cartilage dislocation from external blunt laryngeal trauma in the absence of laryngeal electromyography (LEMG) and to explore the role of early attempted closed reduction in arytenoids cartilage reposition.

Material/Methods

This 15-year retrospective study recruited 12 patients with suspected arytenoid dislocation from external blunt laryngeal trauma, who were evaluated through 7 approaches: detailed personal history, voice handicap index (VHI) test, indirect laryngoscope, flexible fiberoptic laryngoscope, video strobolaryngoscope, and/or high-resolution computed tomography (CT), and, most importantly, the outcomes after attempted closed reduction under local anesthesia. They were divided into satisfied group (n=9) and dissatisfied group (n=3) based on their satisfied with voice qualities at 1 week after the last closed reduction manipulation.

Results

Each patient was diagnosed with arytenoid dislocation caused by external blunt laryngeal trauma. In the satisfied group, VHI scores and maximum phonation time (MPT) at 1 week after the last reduction were significantly improved compared with those before the procedure (P<0.05). Normal or improved mobility and length of the affected vocal fold were also noted immediately after the end of the last closed reduction. The median time interval between injury and clinical intervention in satisfied group was 43.44±34.13 days, much shorter than the median time of 157.67±76.07 days in the dissatisfied group (P<0.05).

Conclusions

Multimodality assessment protocols are essential for suspected arytenoid dislocation after external blunt laryngeal trauma. Early attempted closed reduction should be widely recommended, especially in health facilities without LEMG, mainly, because it could be helpful for early diagnosis and treatment of this disease. In addition, early closed reduction could also improve the success of arytenoid reduction.

Diagnostic and therapeutic pitfalls in benign vocal fold diseases

More than half of patients presenting with hoarseness show benign vocal fold changes. The clinician should be familiar with the anatomy, physiology and functional aspects of voice disorders and also the modern diagnostic and therapeutic possibilities in order to ensure an optimal and patient specific management. This review article focuses on the diagnostic and therapeutic limitations and difficulties of treatment of benign vocal fold tumors, the management and prevention of scarred vocal folds and the issue of unilateral vocal fold paresis.

Differentiating arytenoid dislocation and recurrent laryngeal nerve paralysis by arytenoid movement in laryngoscopic video

OBJECTIVE

To present a new method of quantifying arytenoid movement during inspiration and determine if it can be used to distinguish arytenoid dislocation from vocal fold paralysis.

STUDY DESIGN

Case series with chart review.

SETTING

Retrospective study conducted in a university laboratory based on university hospital data.

SUBJECTS AND METHODS

Endoscopic videos from 8 patients with dislocation and 5 patients with vocal fold paralysis diagnosed by electromyography were included. Vector analysis measured cuneiform movement, an indirect measurement of arytenoid movement, during 1 inspiration. Measurements normalized and not normalized to vocal fold length were evaluated. Interrater reliability (2 raters) and intrarater reliability (1 rater performing the analysis twice) were evaluated using intraclass correlation coefficient (ICC) analysis. Raters were blinded to subject group during analysis.

RESULTS

Pixel-valued cuneiform movement was 81.16 ± 25.62 for dislocation and 30.22 ± 23.60 for paralysis (P = .019). Unitless cuneiform movement was 0.58 ± 0.17 for dislocation and 0.24 ± 0.18 for paralysis (P = .030). Interrater ICC was 0.942 for pixel-valued measurements and 0.962 for unitless measurements. Intrarater ICC was 0.909 for pixel-valued measurements and 0.881 for unitless measurements.

CONCLUSIONS

Both pixel-valued and unitless measures of arytenoid movement were significantly greater in arytenoid dislocation than vocal fold paralysis. Pixel-valued measurements were included to demonstrate the ability to make quantitative comparisons across subjects without precise knowledge of camera precision, provided position is approximately stable, as each measurement is inherently normalized by vocal tract length. Future studies will apply this new method of evaluating vocal fold immobility disorders on a larger scale and incorporate a more diverse group of etiologies.

Treatment outcomes of closed reduction of arytenoid dislocation

CONCLUSION

Closed reduction is an effective and safe treatment method for arytenoid dislocation. Early closed reduction of arytenoid cartilage plays an important role in voice recovery.

OBJECTIVE

The study reviewed the clinical characteristics of arytenoid dislocation with the aim of identifying factors influencing voice recovery in the closed reduction of arytenoid dislocation.

METHODS

A retrospective chart review was performed at Chonnam National University Hospital for the period from January 2007 to March 2012.

RESULTS

Eleven patients with arytenoid dislocation were identified. The causes of arytenoid dislocation were intubation (n = 9) and blunt trauma (n = 2). All cases of arytenoid dislocations were treated by closed reduction. There were no major complications resulting from surgical intervention. Six of the 11 patients (54.5%) regained normal voice and vocal fold movement after closed reduction. Five patients (45.5%) had significant voice improvement postoperatively. In arytenoid dislocation due to blunt trauma, the duration between injury and voice improvement was much longer than in other causes of arytenoid dislocation (p = 0.012).

High-force simulated intubation fails to dislocate cricoarytenoid joint in ex vivo human larynges

OBJECTIVES

We assessed the likelihood of arytenoid dislocation during intubation through the application of controlled force.

METHODS

Six cadaveric human larynges were mounted in an apparatus for simulating forcible collision with the arytenoid complexes. An endotracheal tube tip probe (ETTP) was used to push one arytenoid complex, and a non-slip probe (NSP) was tested on the other. Increasing pressure was applied until the probes either slipped or reached 5 kg of force. Dissection was then performed to assess the integrity of the cricoarytenoid ligament. The forces obtained by pushing an endotracheal tube against an electronic balance were measured to estimate the maximal possible intubating force.

RESULTS

None of the ETTP or NSP trials disrupted the cricoarytenoid joint ligaments, and the joint never appeared to be dislocated. The mean maximal forces were 1.8 kg for the ETTP (after which, slippage consistently occurred) and 4.7 kg for the NSP. The mean maximal forces from an endotracheal tube pushed against a scale were 1.5 kg (without stylet) and 4.6 kg (with stylet).

CONCLUSIONS

Arytenoid dislocation did not happen, and gross disruption of the joint capsule or ligament did not occur, even when the testing approximated the maximum force achievable under extreme conditions. Endotracheal tube insertion thus seems unlikely to cause arytenoid dislocation.

Idiopathic subglottic stenosis in pregnancy: A deceptive laryngoscopic view

A 28-year-old lady with term gestation, pre-eclampsia and a vague history of occasional breathing difficulty, on irregular bronchodilator therapy, was scheduled for category 1 lower segment caesarean section in view of foetal distress. A Cormack-Lehane grade 1 direct laryngoscopic view was obtained following rapid sequence induction. However, it was not possible to insert a 7.0 or 6.0 size styleted cuffed tracheal tube in two attempts. Ventilation with a supraglottic device was inadequate. Airway was secured with a 4.0 size microlaryngeal surgery tube with difficulty. Computed tomography scan of the neck following tracheostomy for failed extubation revealed subglottic stenosis (SGS) with asymmetric arytenoid calcification. This report describes the management of a rare case of unrecognised idiopathic SGS in pregnancy.

Characteristics of Vocal Fold Immobility following Endotracheal Intubation

Objectives:

We investigated the clinical and laryngeal electromyography (LEMG) characteristics and the outcome of closed reduction of arytenoid cartilage dislocation in patients with vocal fold immobility (VFI) following endotracheal intubation.

Methods:

Sixty patients with VFI following endotracheal intubation were included. Closed reduction was performed under local anesthesia in 54 cases. Another 6 patients did not undergo an intervention. Laryngeal behaviors and voice function were evaluated. Forty-five patients underwent LEMG testing.

Results:

All patients complained of persistent hoarseness immediately following surgery. The LEMG results for 29 of 45 patients showed normal patterns (15 cases) or mildly abnormal patterns (14 cases) on the affected side. Sixteen cases displayed apparent abnormal LEMG patterns on the affected side. The voices of all 54 patients improved after reduction. The movement of the affected vocal folds recovered to normal in 51 cases. One month after reduction, neuromuscular function had improved in 29 of 30 cases. Among the 6 patients who did not undergo intervention, 3 had normal or slightly hoarse voices, and 3 experienced moderate hoarseness.

Conclusions:

Vocal fold immobility following endotracheal intubation is typically caused by arytenoid dislocation. Some instances were accompanied by an abnormality of the recurrent laryngeal nerve. A timely closed arytenoid reduction should be performed to restore patients' normal voices and vocal fold mobility. Our reduction technique under local anesthesia can be performed easily and obtains satisfactory outcomes within 6 weeks after endotracheal intubation.

Cadaveric position of unilateral vocal cord: a case of cricoid fracture with ipsilateral arytenoid dislocation

We report a case of cricoid cartilage fracture with unilateral arytenoid dislocation following a motorcycle accident. This 25 year old male sustained blunt injury to the head, face and neck. He presented late to the hospital with one week history of dysphonia. Laryngoscopy revealed cadaveric position of the non-functioning left vocal cord. CT and MRI showed laterally displaced left vocal cord. Displaced fractures were noted in the cricoid at the junction of lamina with the anterior arch on the left side and at the right side of the anterior arch, along with dislocated left arytenoid resulting in ipsilateral vocal cord palsy. Medialization thyroplasty was performed to improve his phonation. Laryngeal trauma warrants close monitoring because of the risk of airway compromise. Radiologists play a crucial role in early diagnosis and should always have high index of suspicion. Recognition of laryngeal injury is important for initial resuscitation as well as for long term airway and vocal function.