Arytenoid subluxation: diagnosis and treatment

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.

Unilateral Vocal Fold Immobility After Prolonged Endotracheal Intubation

Importance

Endotracheal intubation and mechanical ventilation are life-saving treatments for acute respiratory failure but are complicated by significant rates of dyspnea and dysphonia after extubation. Unilateral vocal fold immobility (UVFI) after extubation can alter respiration and phonation, but its incidence, risk factors, and pathophysiology remain unclear.

Objectives

To determine the incidence of UVFI after prolonged (>12 hours) mechanical ventilation in a medical intensive care unit and investigate associated clinical risk factors for UVFI after prolonged mechanical ventilation.

Design, Setting, and Participants

This subgroup analysis of a prospective cohort study was conducted in a single-center medical intensive care unit from August 17, 2017, through May 31, 2018, among 100 consecutive adult patients who were intubated for more than 12 hours. Patients were identified within 36 hours of extubation and recruited for study enrollment. Those with an established tracheostomy prior to mechanical ventilation, known laryngeal or tracheal pathologic characteristics, or a history of head and neck radiotherapy were excluded.

Exposure

Invasive mechanical ventilation via an endotracheal tube.

Main Outcomes and Measures

The incidence of UVFI as determined by flexible nasolaryngoscopy.

Results

One hundred patients (62 men [62%]; median age, 58.5 years [range, 19.0-87.0 years]) underwent endoscopic evaluation after extubation. Seven patients had UVFI, of which 6 cases (86%) were left sided. Patients with hypotension while intubated (odds ratio [OR], 10.8; 95% CI, 1.6 to ∞), patients requiring vasopressors while intubated (OR, 16.7; 95% CI, 2.4 to ∞), and patients with a preadmission diagnosis of peripheral vascular disease (OR, 6.2; 95% CI, 1.2-31.9) or coronary artery disease (OR, 5.1; 95% CI, 1.0-25.5) were more likely to develop UVFI.

Conclusions and Relevance

Unilateral vocal fold immobility occurred in 7 of 100 patients in the medical intensive care unit who were intubated for more than 12 hours. Unilateral vocal fold immobility was associated with inpatient hypotension and preadmission vascular disease, suggesting that ischemia of the recurrent laryngeal nerve may play a role in disease pathogenesis.

Quantifying Vocal Power: Correlation of Whole-Body Anaerobic Power to Vocal Function Measures

Purpose The purpose of this preliminary study was to identify a vocal task that could be used as a clinical indicator of the vocal aptitude or vocal fitness required for vocally demanding occupations in a manner similar to that of the anaerobic power tests commonly used in exercise science. Performance outcomes for vocal tasks that require rapid acceleration and high force production may be useful as an indirect indicator of muscle fiber complement and bioenergetic fitness of the larynx, an organ that is difficult to study directly. Method Sixteen women (age range: 19-24 years, M _age = 22 years) were consented for participation and completed the following performance measures: forced vital capacity, three adapted vocal function tasks, and the horizontal sprint test. Results Using a within-participant correlational analyses, results indicated a positive relationship between the rate of the last second of a laryngeal diadochokinesis task that was produced at a high fundamental frequency/high sound level and anaerobic power. Forced vital capacity was not correlated with any of the vocal function tasks. Conclusions These preliminary results indicate that aspects of the laryngeal diadochokinesis task produced at a high fundamental frequency and high sound level may be useful as an ecologically valid measure of vocal power ability. Quantification of vocal power ability may be useful as a vocal fitness assessment or as an outcome measure for voice rehabilitation and habilitation for patients with vocally demanding jobs.

Prolonged Intubation Injuries of the Larynx: Endoscopic Diagnosis, Classification, And Treatment

Laryngeal trauma from prolonged endotracheal intubation occurs in patients of all ages. Most changes are superficial and heal quickly. Injuries that are found consistently during intubation include nonspecific changes, edema, granulation tissue, ulceration, and othermiscellaneous injuries. In thispapersignificant, severe, and lasting trauma of the larynx has been classified on thebasis of theknown factors in pathogenesis, observations made atendoscopy, and photographic documentation. This classification has required introduction of new descriptive terminology: "tongues of granulation tissue," "ulcerated troughs," "healed furrows," and "healed fibrous nodule." During intubation the degree of injury can be precisely assessed under general anesthesia by using telescopes for image magnification, thus assisting adecision whether to continue intubation orperform tracheotomy to minimize long-term morbidity. Changes that are found after extubation result from granulation tissue, ulceration, ora combination of both and have been illustrated on flow charts; a knowledge and understanding of these sequelae allows them to be identified by both indirect and direct laryngoscopy so that treatment can be planned.

Laryngoscopy in Bilateral Vocal Fold Immobility: Can You Make a Diagnosis?

Objectives:

This study explores whether videoendoscopic findings and patient history help make the diagnosis in bilateral vocal fold immobility (BVFI).

Methods:

Medical records from 1995 to 2003 were searched to identify patients with posterior glottic stenosis (PGS) and bilateral vocal fold paralysis (BVFP) who also had videoendoscopic examinations. Videoendoscopic examination findings that could help differentiate PGS from BVFP were identified a priori. A weighted scoring index, based on the adjusted odds ratios of significant examination findings on multiple logistic regression, was derived. Associations between the weighted scoring index, patient history, and diagnosis were then evaluated.

Results:

Twenty-six patients with BVFP and 28 patients with PGS were identified. Posterior glottic scar (weight = 2), medial arytenoid erosion with a widened posterior glottis (weight =1), and appropriate vocal fold motion (weight = 1) were significant variables (p ≤ .05, multiple logistic regression) and constituted the weighted scoring index. A weighted scoring index of ≥ 2 and a history of prolonged intubation predicted PGS in 95.2% of cases. A weighted scoring index of ≤ 1 and a history of neck surgery predicted BVFP in 95.0% of cases.

Conclusions:

The weighted scoring index with the patient history provides an objective tool for diagnosing BVFI.

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.

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).

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.

Arytenoid subluxation after a bout of coughing: a rare case

Korman et al (Laryngoscope.1973;83:683-690) first reported arytenoid dislocation as a rare and unusual complication of intubation. Since then, the terms arytenoid dislocation and arytenoid subluxation (AS) have been used interchangeably to describe disruption of the cricoarytenoid joint. Only 74 cases of AS have been reported in the literature to date. The most common cause of AS is intubation trauma and external neck injury. Only 1 case of AS due to coughing has been documented. Arytenoid subluxation cases are often misdiagnosed as vocal fold paralysis. A high index of suspicion based on the history, examination findings, and objective tests helps in early diagnosis and, thus, early surgical intervention. We present a rare etiology of AS due to a bout of coughing, which was diagnosed early and reduced under general anesthesia with complete reversibility of vocal fold motion, thus restoring normal voice function.

A promising new technique for closed reduction of arytenoid dislocation

Objectives:

To study the effect of a new technique for closed reduction of dislocated arytenoids.

Methods:

The study included 21 females (72.4 per cent) and eight males (27.6 per cent) with a diagnosis of arytenoid dislocation. There were 18 cases of left arytenoid dislocation and 11 of right arytenoid dislocation.Twenty-eight cases had anteromedial dislocation and one had posterolateral dislocation. All patients were treated with closed reduction using custom-made metal rods and an operating microscope, under general anaesthesia.

Results:

Post-operatively, 21 patients’ voices returned completely to normal (including full vocal fold mobility), five had an improved voice and three failed to show any improvement. There were no post-operative complications.

Conclusion:

This new closed reduction technique is a safe procedure for patients with dislocated arytenoids. It is repeatable and the outcome is reliable and effective. Closed reduction can be a useful treatment for arytenoid dislocation.

Arytenoid subluxation after a difficult intubation treated successfully with voice therapy

Arytenoid subluxation is a rare laryngeal injury that may follow instrumentation of the airway and present as hoarseness, vocal fatigue, stridor, dysphagia, odynophagia and sore throat. We report the case of an 88-year-old man with type 2 diabetes mellitus who developed this complication during a difficult intubation where a Macintosh laryngoscope and gum elastic bougie were used to facilitate intubation. Previously considered to play a minor role in treatment, voice therapy was used successfully in this patient to correct subluxation of the arytenoid, with prompt resolution of his symptoms.

Arytenoid cartilage dislocation: a 20-year experience

SUMMARY

Arytenoid cartilage dislocation is an infrequently diagnosed cause of vocal fold immobility. Seventy-four cases have been reported in the literature to date. Intubation is the most common origin, followed by external laryngeal trauma. Decreased volume and breathiness are the most common presenting symptoms. We report on 63 patients with arytenoid cartilage dislocation treated by the senior author (RTS) since 1983. Significantly more posterior than anterior dislocations were represented. Although reestablishing joint mobility is difficult, endoscopic reduction should be considered to align the heights of the vocal processes. This process may result in significant voice improvement even long after the dislocation. Strobovideolaryngoscopy, laryngeal electromyography, and laryngeal computed tomography (CT) imaging are helpful in the evaluation of patients with vocal fold immobility to help distinguish arytenoid cartilage dislocation from vocal fold paralysis. Familiarity with signs and symptoms of arytenoid cartilage dislocation and current treatment techniques improves the chances for optimal therapeutic results.

Blunt laryngeal trauma resulting in arytenoid dislocation and dysphonia

We present a case of left arytenoid dislocation due to blunt laryngeal trauma causing a subsequent large granuloma formation resulting in dysphonia and stridor. The patient underwent emergency excision of the obstructive granuloma and speech therapy was started post-operatively. A few weeks after surgery, the granuloma started to recur and laryngeal manipulation by a specialist osteopath was performed. A few weeks after the conservative management, the recurred granuloma resolved completely and patient's voice improved remarkably. Dislocation of the arytenoid cartilage due to blunt trauma is relatively rare and a consequent spontaneous granuloma formation has not been reported so far in the literature. This is also the first report about efficacy of speech therapy combined with laryngeal manipulation in the management of the arytenoid dislocation and the subsequent laryngeal granuloma.

Bilateral vocal fold paralysis: an unusual treatment with botulinum toxin

We presented a patient with bilateral vocal fold paralysis treated with intralaryngeal Botox injection to improve the glottal airway. The use of Botox in this manner has not been previously reported and highlights the value and role of intralaryngeal Botox in changing the configuration of the glottis. The concept and various approaches for using Botox to alter pathologic vocal fold position is reviewed and discussed.

[Not all vocal cord failure following thyroid surgery is recurrent paresis due to damage during operation. Statement of the German Interdisciplinary Study Group on Intraoperative Neuromonitoring of Thyroid Surgery concerning recurring paresis due to intubation]

Since the phoniatrician H. Bauer described the first case of recurrent laryngeal nerve palsy most likely caused by intubation some 45 years ago, several case reports have been published. However, systematic analyses regarding the frequency of recurrent laryngeal nerve palsies due to intubation are scarce, and none of them has used the proper methods to demonstrate clearly that such a mechanism exists. Currently available data justify the assumption that not every recurrent laryngeal nerve palsy following thyroid surgery is due to the operation itself and that the damage caused by intubation, however, may only account for a minority of these cases. The differential diagnosis of postoperative recurrent laryngeal nerve palsy requires the use of specific tools which go beyond simple laryngoscopy and include stroboscopy as well as intra- and extralaryngeal electromyography. A partial palsy of recurrent laryngeal nerve due to intubation would be associated with severe dysphonia or aphonia, not with dyspnea because of the typical intermediate position of the paralyzed vocal folds with a normal electromyographic function of the cricothyroid muscle. The use of these methods to identify the nature of postoperative recurrent laryngeal nerve palsy is recommended in cases of regular intraoperative neuromonitoring but postoperatively impaired function of the vocal cords.

Electromyography and the immobile vocal fold

Laryngeal EMG has become a useful tool for the otolaryngologist in the four decades since the pioneering work of Faaborg-Anderson and Buchtal. It is able to distinguish between mechanical limitation and denervation in an immobile vocal fold. In the paralyzed vocal fold, it can guide workup by pointing to the site of the lesion. In the hands of a circumspect clinician, it can provide clinically valuable information regarding prognosis. Useful application of laryngeal EMG must rest on the basic fact that it isa qualitative test. Because of factors like sampling error, interfering signal from neighboring muscles, difficulties in needle placement, and our in-complete understanding of reinnervation physiology, the boundary between sophisticated, subtle interpretation and overreading is particularly difficult to distinguish. EMG diagnosis is based on patterns of abnormalities over time and, like other tests, requires interpretation in a clinical context. As in any such undertaking, there is no substitute for good judgment and experience. The most important benefit of clinical use of laryngeal EMG may be that it has catalyzed and broadened interest in laryngeal neurophysiology in the same way that stroboscopy has focused attention on the structure and function of the vocal fold lamina propria. The continuing refinement of electrodiagnostic approaches to the larynx that has resulted, including quantitative, single-fiber. and vector laryngeal EMG, and evolving methods of nerve conduction testing will continue to yield important insights into mechanisms of neural control that are likely to drive developments in the treatment of vocal fold paralysis in the future.

Topography and interactions of the arytenoid and cricoid articular facets: Implications for vocal process positional shifts

Using new computer applications and digital technologies, we provide a rigorous description and realistic illustrations of the arytenoid-on-the cricoid rotations. We also provide the articular facet topography and interactions that underlay those rotations and the concomitant vocal process positional shifts. The thyroid cartilage and all soft tissues were removed from three excised, preserved, normal, adult human larynges without disturbing the crico-arytenoid (CA) articular capsule. Three CA assemblies were thus prepared and used to digitize arytenoid rotations and vocal process positional shifts, and, after disarticulation, also the surface contour of the arytenoid and cricoid facets, and the cricoid lumen margin. The digitized data served to computer generate 2D and 3D graphic visualizations of the vocal process positional shifts, of the topography of the facets, and of the facet motion sequences that show that the anteroposteriorly concave arytenoid facet slides and conjunctly rotates on the anteroposteriorly convex cricoid facet. Visual details of all graphic representations and facet motion sequences were essentially identical across the three assemblies. Then, based on the computer generated data obtained from the largest of the CA assemblies, 3D, realistic, and hand-drawn images were made that illustrate the directions in which the arytenoids can rotate and the vocal processes concomitantly shift positions. Results indicate that when the arytenoids rotate by sliding from anterior to posterior on the cricoid facets about a primary axis of motion aligned from medial, posterior, and superior, to lateral, anterior, and inferior, their vocal processes shift positions along a plane obliquely oriented from anterior and medial, to posterior and lateral, and from inferior and medial, to superior and lateral.

Long-term complications of artificial airways

In summary, long-term complications of artificial airways are rare but important sequelae of artificial airways. Many of the potential long-term complications of translaryngeal intubation and tracheotomy are similar and overlapping. Although most patients who undergo these procedures tend to tolerate them without difficulties, significant morbidity and mortality may occur. Identifying the exact cause of the complication may not be possible at times, due to the multiple risk factors involved in the pathogenesis. It is hoped that understanding these potential complications will lead to a more vigilant preventive measures during the institution of long-term artificial airways and a judicious early search for the underlying pathology when a complication is suspected.

Arytenoid subluxation

BACKGROUND

Disruption of the cricoarytenoid joint is uncommon and possibly underdiagnosed.

AIM

To highlight the diagnosis of arytenoid subluxation and its management.

METHOD

Two case reports.

CONCLUSION

Arytenoid subluxation is a rare condition that should always be considered in patients presenting with symptoms following upper airway instrumentation or external trauma to the neck. Early diagnosis optimises the possibility of restoring normal voice and laryngeal function.

An unusual cause of foreign-body sensation in the throat: corniculate cartilage subluxation

Corniculate cartilage subluxation is a pathology that has not been reported in the medical literature. Causing vague pharyngeal symptoms, this disease entity may be overlooked or misdiagnosed as chronic nonspecific pharyngitis, globus pharyngis, or laryngopharyngeal reflux disease. A careful laryngoscopic examination is the key to detect this disorder. In this article, we present a 45-year-old patient with the complaints of foreign-body sensation in the throat, difficulty in swallowing solid food, and an urge to turn his head toward the left during the act of swallowing. His laryngeal examination revealed corniculate cartilage subluxation, and excision of the subluxated cartilage was performed by microlaryngoscopic surgery. The patient was free of his symptoms immediately after the operation and remained as such in the 6 months of follow-up.

Management of bilateral arytenoid cartilage fixation versus recurrent laryngeal nerve paralysis

Bilateral arytenoid cartilage fixation (ACF) closely resembles vocal cord immobility due to recurrent laryngeal nerve paralysis (RLNP). This study sought to determine the etiologic differences between these two entities and to derive conclusions about treatment. The charts of 218 consecutive adult patients with immobility of both vocal cords requiring surgery for airway restoration were reviewed. The results of laryngeal electromyography and laryngotracheoscopy were used to distinguish ACF from RLNP. In 186 patients (85.3%), RLNP was identified. Of these, 154 paralyses (82.8%) were caused by surgical interventions, 5 (2.7%) were caused by previous intubation, 16 (8.6%) were caused by various malignancies, and 7 (3.8%) were neurogenic. In 4 patients (2.2%), the cause remained unclear. We identified ACF in 32 patients. The etiologic factors included previous long-term intubation in 22 patients (68.8%), short-term intubation in 3 patients (9.4%), Wegener's granulomatosis in 3 patients (9.4%), rheumatoid arthritis in 2 patients (6.3%), previous laryngeal surgery in 1 patient (3.1%), and caustic ingestion in 1 patient (3.1%). Additional second-site airway stenosis was found in 10 of the RLNP patients (5.4%) and in 15 of the ACF patients (46.9%). All RLNP patients had endoscopic surgery without temporary tracheotomy. Eighteen ACF patients required open surgery, and 4 were managed endoscopically but required temporary tracheotomy. The etiologic factors were significantly different for the two entities under study. Additional sites of stenosis were more frequent in ACF patients. Stenosis due to RLNP could be managed endoscopically without preliminary tracheotomy, while ACF frequently required open surgery and temporary tracheotomy.

A biomechanical study of the human cricoarytenoid joint

OBJECTIVES/HYPOTHESIS

To develop a model to investigate the biomechanics of the cricoarytenoid joint and establish stiffness, laxity, and range of motion of the cricoarytenoid joint in adult human larynges.

STUDY DESIGN

Laboratory investigation of freshly frozen larynges from adult humans, measuring the stiffness, laxity, and range of motion in intact and injured cricoarytenoid joints.

METHODS

Eight normal-appearing frozen cadaver larynges from adult humans were studied. The cricoid cartilage was fixed to a load cell sensitive to forces in three dimensions. A probe was rigidly fixed to the arytenoid cartilage and attached to a frame to allow active rotation, rocking, and gliding of the arytenoid. A computer program simultaneously recorded forces generated by these motions and tracked the motion of the arytenoid in three dimensions. The joint was studied before and after injury to the posterior cricoarytenoid ligament, and the joint surfaces were digitized after completion of these studies.

RESULTS

A successful method of evaluating the biomechanical properties of the cricoarytenoid joint was developed. Comparing intact and injured joints confirmed that laxity and range of motion increased during rocking, gliding, and rotational motion when the cricoarytenoid ligament had been divided. Stiffness measurements for rocking, rotation, and gliding also were documented.

CONCLUSIONS

The model of study introduced in this report provides a significant and unique method of investigating the biomechanics of the cricoarytenoid joint, allowing insight into the basic joint characteristics and alteration in joint biomechanics related to injuries and surgical procedures. Dividing the cricoarytenoid ligament increases laxity and range of motion in sagittal rocking, gliding, and axial rotation. Secondary constraints on the joint provide significant stiffness of greater degrees of displacement. Further studies should provide insight into the significant secondary elements supporting the joint and into the mechanisms of cricoarytenoid injuries, as well as the effect of surgical procedures on the cricoarytenoid joint.

Three-dimensional analysis of cricoarytenoid joint motion

The normal motion of the cricoarytenoid joint was characterized and analyzed in this study using seven fresh cadaver larynges mounted rigidly in an external fixator apparatus after radiopaque markers were attached to laryngeal landmarks. Fluoroscopic imaging and recording was performed of top, front, and side views while the arytenoid cartilages of each larynx were manipulated through the full range of motion from adduction to abduction. Computer video capture was performed of the recordings and editing of still frames accomplished to generate three-dimensional plots of cricoarytenoid joint motion, which are shown in the manuscript. Selective and varying sequential disconnection of muscular and ligamentous structures to the arytenoid cartilage was achieved to determine their contributions to cricoarytenoid joint motion limitations and stability. The vocalis ligament, cricoarytenoid ligament, and conus elasticus are most important in controlling abduction, whereas the posterior cricoarytenoid muscle and conus elasticus are crucial in limiting adduction. The vocalis ligament prevents posterior displacement of the vocal process, while the cricoarytenoid ligament and a newly described ligament, the posterior capsular ligament, restricts anterior vocal process migration. Another ligament, the anterior capsular ligament, is described, which limits backward arytenoid cartilage tilting and lateral movement of the arytenoid cartilage on the cricoid cartilage facet. Section of the vocalis ligament with underlying conus elasticus produced reducible lateral arytenoid cartilage subluxation. Confirmation of cricoarytenoid joint facet relationships in full adduction and abduction was accomplished by fixation of the cricoarytenoid joints of one larynx in the two positions with adhesive, and subsequent exposure of the joint surfaces. Review of literature detailing human laryngeal embryological development shows that the glottis and arytenoid cartilages are formed in adduction, which explains how cricoarytenoid joint ligaments collaborate to achieve accurate vocal process approximation in adduction despite side-to-side asymmetries of the cricoarytenoid joint structures in the same larynges.

Utility of helical computed tomography in the study of arytenoid dislocation and arytenoid subluxation

Conventional computed tomography (CT) has been considered a mainstay in the evaluation of the larynx. A major difficulty with utilizing this modality, especially in the study of the arytenoid, is the time necessary to perform a thin-slice examination through a structure that has a propensity to move with respiration and swallowing. Helical CT not only significantly reduces the time necessary to study the larynx, but enables one to perform multiple high-resolution multiplanar reconstructions. Eleven patients with arytenoid abnormalities documented by strobovideolaryngoscopy or direct laryngoscopy were imaged with helical CT. A comprehensive radiographic examination illustrating the cricoarytenoid relationship in all of the subjects was completed in less than 20 seconds by using axial reconstructions in 2-mm-thick slices at 1-mm intervals, with subsequently derived sagittal and coronal reconstructions. Helical CT may be a useful adjunct in the diagnosis of arytenoid subluxation or dislocation.

Disease-specific survival and locoregional control in tonsillar carcinoma

In a nationwide survey on oropharyngeal carcinoma in the Netherlands (1986-1990), 380 patients with a tonsillar carcinoma were retrospectively studied. The records of 268 (71%) men and 112 (29%) women with a median age of 59 yr (range 31-91), who had squamous cell carcinoma (272 patients, 98%) or undifferentiated carcinoma (8 patients, 2%) were reviewed with respect to treatment, disease-specific survival and locoregional control. Distribution by stage according to the UICC'92 system was: 27 patients (7%) stage I, 59 (15%) stage II, 99 (26%) stage III, 182 (48%) stage IV and 13 patients (3%) unknown stage. Using a previously reported revised staging system the following distribution was obtained: 118 patients (31%) stage I, 120 (31%) stage II, 67 (18%) stage III, 54 (14%) stage IV and 21 patients (6%) with an unknown stage. Treatment consisted of radiotherapy alone in 231 patients (61%), surgery and radiotherapy in 101 (27%), surgery alone in 30 (8%), chemotherapy in 5 (2%) and 13 patients (3%) did not receive any treatment. At 5-yr the overall survival was 32%, the disease-specific survival 42% and the locoregional control 61%. In patients treated with radiotherapy alone the disease-specific survival was 39%, for surgery and radiotherapy 53% and for surgery alone 83%. The disease-specific survival according to UICC'92 stage was 71% in stage I, 59% in II, 50% in III and 32% in stage IV (P < 0.0001). In the revised staging the survival figures were 63% in stage I, 43% in II, 31% in III and 9% in IV (P < 0.0001). The two staging systems appeared to be comparable in prognostic discrimination; the clinical relevance of the revised stage might, however, be slightly superior to the UICC'92 version. The difference in results after radiotherapy alone and surgery + radiotherapy remained significant, also after adjusting for stage (P < 0.0001).

Value of electromyography in differential diagnosis of laryngeal joint injuries after intubation

Laryngeal joint injury or arytenoid dislocation is not an uncommon complication resulting from intubation trauma, and is best evaluated by laryngeal electromyography (EMG) combined with laryngoscopic examinations. Two cases of cricoarytenoid joint injuries after intubation are reported along with laryngeal EMG findings. Early diagnosis of arytenoid dislocation is important for appropriate surgical management and better prognosis. However, the reported cases, because of delayed referrals, showed prolonged cricoarytenoid joint injuries associated with thyroarytenoid muscle denervation or myopathy, and resultant vocal fold immobility. The results of laryngeal EMG in cricoarytenoid joint injuries can be classified into three different patterns: 1) normal recruitment, 2) myopathy, and 3) denervation or reinnervation of the thyroarytenoid muscles. It is particularly valuable to sample different portions of the thyroarytenoid muscles with EMG in order to evaluate different patterns or pathologic changes of the muscles and nerve paralysis.

Postintubation arytenoid subluxation

Arytenoid subluxation (AS), ie, malpositioning of the arytenoid cartilage with abnormal but existent contact between the joint surfaces, is an uncommon entity, and fewer than 70 cases have been reported, 26 of which were in a recently published series. Usually, AS is the result of upper airway instrumentation, and only a few cases were reported to occur with external trauma to the neck. Some predisposing factors and possible mechanisms have been suggested, but the reason for its occurrence remains obscure. Hoarseness and, to a lesser degree, dysphagia, odynophagia, cough, and sore throat may be indicative of AS. Diagnosis is established by the clinical course, laryngoscopy, and computed tomography. Electromyography and strobovideolaryngoscopy are additional diagnostic measures described. We report 7 cases of postintubation AS of long standing. Three of these patients had prior unilateral vocal cord paralysis, formerly undescribed as a possible contributing factor for AS. The pertinent literature is reviewed and treatment options are discussed.

A comparison of direct, indirect, and fiberoptic laryngoscopy to evaluate vocal cord paralysis after thyroid surgery

After thyroidectomy, the anesthesiologist usually performs a laryngoscopy to detect laryngeal edema and nerve palsies. The goal of this study was to compare three different methods of laryngeal examination after tracheal extubation of the patients. For that purpose, between 1990 and 1995, a prospective series of 1608 patients operated for thyroidectomy has been studied. The series was divided into 4 groups. In group I (n = 200), four anesthesiologists have evaluated the efficiency of the immediate postextubation direct laryngoscopy. In group II (n = 100), one anesthesiologist has compared the direct, indirect, and flexible laryngoscopies in every patient in a fixed and timed fashion. In group III (n = 100), the four examiners have evaluated the flexible laryngoscopy at a different timing so as to eliminate the possible temporal relationship of the ease of visualization in group II. In group IV (n = 1208), the four examiners have evaluated flexible laryngoscopy, on a large scale, at any time during the 1-h stay in the recovery room. Special attention was directed to the patients with known cardiovascular diseases. Direct and indirect laryngoscopies were only effective in 76 and 73%, respectively, of the patients, whereas flexible laryngoscopy was effective in 99.6% of them. Flexible laryngoscopy was easy to perform in 96.5% of the patients versus 65 and 55% with direct and indirect laryngoscopies. Finally, variations in monitored cardiovascular parameters were significantly lower with flexible and indirect laryngoscopies than with direct laryngoscopy. These mild variations induced by flexible laryngoscopy were well tolerated by patients with known cardiovascular diseases. Flexible laryngoscopy is the best method for an immediate laryngoscopic examination after thyroidectomy.

The importance of correct stage grouping in oncology. Results of a nationwide study of oropharyngeal carcinoma in The Netherlands

BACKGROUND

In the frame of a nationwide study of oropharyngeal carcinoma in the Netherlands (1986-1990), the current International Union Against Cancer 1992/American Joint Committee on Cancer 1988 staging system was evaluated with respect to patient distribution and prognostic value.

METHODS

Data related to epidemiology, treatment and survival from 640 patients referred for primary treatment were analyzed. Staging was first evaluated in a proportional-hazard regression analysis controlled for these data. Next, all possible combinations of T, N, and M were tested in a stepwise backward elimination model until all remaining indicator variables had a P value of less than 0.05. New stages were defined, based on the coefficients of the remaining indicator variables.

RESULTS

The revised stages revealed two advantages compared with the UICC 1992/AJCC 1988 version: a more balanced distribution of patients (31% in Stage I, 31% in Stage II, 18% in Stage III, 14% in Stage IV, and 5% unknown in the revised staging system versus 7% in Stage I, 17% in Stage II, 24% in Stage III, 50% in Stage IV, and 2% unknown in the UICC 1992/AJCC 1988 staging system), and an improved prognostic discrimination for the disease specific survival (5-year results in the revised staging were 67% in Stage I, 42% in Stage II, 28% in Stage III, and 11% in Stage IV, versus 68% in Stage I, 64% in Stage II, 44% in Stage III and 27% in Stage IV in UICC 1992/AJCC 1988).

CONCLUSION

Improvements in the current staging system in patient distribution in the stages in prognostic discrimination is feasible by regrouping the T, N, and M but without redefining the categories themselves.

Carcinoma of the soft palate and the posterior oropharyngeal wall

Between 1966 and 1984, 14 patients with carcinoma of the soft palate and eight patients with a posterior oropharyngeal wall carcinoma were treated at the Netherlands Cancer Institute. In the soft palate group, the majority of patients (10) had small tumours T1-T2; the median patient delay was 1 month (range 0-5). Eleven patients were treated with radiotherapy and three with surgery, as single treatment modalities. Tumour control was achieved in 10 patients following initial treatment. Five-year results for tumour control and overall survival were 67% and 41%, respectively. In the posterior wall group all patients had advanced tumours (T3-T4), after a median patient delay of 4 months (range 0-6). Six patients were treated with radiotherapy, one with surgery only and one with a combination of these. Following the initial treatment, tumour control was achieved in half of the patients. Five-year tumour control was 50%, and overall survival at 5 years was 38%. In conclusion, the tumours in these two sub-sites of the oropharynx differ significantly in the extent of the primary tumour (P < 0.01), posterior wall tumours being more advanced on admission, after a significantly longer history (P < 0.01).

Arytenoid subluxation from blunt laryngeal trauma

Isolated arytenoid dislocation and subluxation are uncommon laryngeal injuries most often resulting from endotracheal intubation. However, these diagnoses must be entertained in all patients having sustained laryngeal trauma. Complaints of dysphonia, pain with phonation, or odynophagia in the setting of laryngeal trauma should include evaluation for possible arytenoid displacement after an airway is secured. Prolonged hoarseness or odynophagia after endotracheal intubation should alert the physician to the possibility of a cricoarytenoid joint injury. This represents the first reported case of isolated arytenoid injury resulting from blunt external trauma to the larynx. The patient had a stable airway without intervention, and the displaced joint spontaneously relocated with resolution of the cricoarytenoid edema and hemarthrosis. We propose that the cricoarytenoid joint was subluxed probably due to edema, hematoma, and/or cricoarytenoid hemarthrosis sustained from blunt laryngeal trauma. We furthermore propose that some cases of cricoarytenoid subluxation may be treated without operative intervention.

Prolonged intubation injuries of the larynx: endoscopic diagnosis, classification, and treatment

Laryngeal trauma from prolonged endotracheal intubation occurs in patients of all ages. Most changes are superficial and heal quickly. Injuries that are found consistently during intubation include nonspecific changes, edema, granulation tissue, ulceration, and other miscellaneous injuries. In this paper significant, severe, and lasting trauma of the larynx has been classified on the basis of the known factors in pathogenesis, observations made at endoscopy, and photographic documentation. This classification has required introduction of new descriptive terminology: "tongues of granulation tissue," "ulcerated troughs," "healed furrows," and "healed fibrous nodule." During intubation the degree of injury can be precisely assessed under general anesthesia by using telescopes for image magnification, thus assisting a decision whether to continue intubation or perform tracheotomy to minimize long-term morbidity. Changes that are found after extubation result from granulation tissue, ulceration, or a combination of both and have been illustrated on flow charts; a knowledge and understanding of these sequelae allows them to be identified by both indirect and direct laryngoscopy so that treatment can be planned.

The clinical differentiation between vocal cord paralysis and vocal cord fixation using electromyography

With newer techniques for laryngeal intervention, it becomes a practical necessity to understand whether an immobile cord is due to neurogenic dysfunction or cricoarytenoid fixation. An objective test for this differentiation is laryngeal electromyography, which can be done as an office procedure with a minimum of discomfort. Our experience in a clinical setting has shown laryngeal electromyography to be efficient in accurately assessing the neuromuscular status of the intrinsic laryngeal musculature.

Intraoperative laryngeal electromyographic assessment of patients with immobile vocal fold

The differential diagnosis of laryngeal ankylosis versus paralysis is occasionally difficult in patients with immobile vocal folds. Eight patients with acute and chronic evidence of vocal fold immobility were investigated by intraoperative electromyography (IEMG) during planned microlaryngoscopy. Bipolar hook wire electrodes were inserted into the thyroarytenoid muscle, of which the electrical activity was monitored during neuromotor blockade and emergence from anesthesia. The normal side and the side with ankylosis or stenosis showed normal IEMG activity. There was progressive recruitment of larger motor units during recovery from muscle relaxation. Patients with laryngeal paralysis failed to show such recruitment patterns. Thus, IEMG can be used as a diagnostic tool during operative laryngoscopy to differentiate neuromotor injury from anatomic causes of vocal fold immobility. The advantages of IEMG are its ease of application and certainty of electrode position. It can also be used to monitor recurrent nerve integrity and detect early laryngospasm. Further IEMG clinical study is warranted.