------------------------------------------------------------------------------ TITLE: ACUTE LARYNGEAL TRAUMA DIAGNOSIS AND MANAGEMENT SOURCE: Dept. of Otolaryngology, UTMB, Grand Rounds DATE: SEPTEMBER 30, 1989 RESIDENT PHYSICIAN: Joseph J. Bradfield, M.D. FACULTY: Byron J. Bailey, M.D. DATABASE ADMINISTRATOR: Melinda McCracken, M.S. -------------------------------------------------------------------------------- "This material was prepared by resident physicians in partial fulfillment of educational requirements established for the Postgraduate Training Program of the UTMB Department of Otolaryngology/Head and Neck Surgery and was not intended for clinical use in its present form. It was prepared for the purpose of stimulating group discussion in a conference setting. No warranties, either express or implied, are made with respect to its accuracy, completeness, or timeliness. The material does not necessarily reflect the current or past opinions of members of the UTMB faculty and should not be used for purposes of diagnosis or treatment without consulting appropriate literature sources and informed professional opinion." Historical Review A. Otolaryngologists have struggled with the problem of laryngeal stenosis for decades: 1. Von Schroetter ushered in the modern era in the 1880's when he began using a core mold or lumen keeper. 2. Scmiegelow in the 1920's began placing molds at the time of open operations. 3. At the same time, Arbuckle began treating laryngeal stenoses via laryngofissure with the placement of a sponge surrounded by a STSG to graft the lumen. 4. Figi in the 1930's and 40's reported a large series and recommended the open treatment of all extensively scarred larynges. 5. McNaught in the 50's proposed the use of a keel for anterior webs. Of note is that the procedure caught on after the report of a single case treated this way. B. The treatment of acute injuries suffered from neglect until more recently. 1. Until fairly recently, it appears that most acute injuries were allowed to heal until stenosis occurred. 2. Harris and Ainsworth in 1965 reported a large series of injuries treated acutely with excellent results. They used a STSG sutured raw side out to a sponge stent. 3. Olson and Miles in 1971 reported a series of 26 cases from which they devised indications for exploration and surgical repair. 4. Most recently, Schaefer has published a series of articles reporting a large series of patients (120) treated at Parkland Hospital, and further refined the diagnosis and management of acute laryngeal trauma. Incidence and Distribution of Laryngeal Trauma A. The incidence of significant laryngeal trauma has been estimated at between 1 in 14583 and 1 in 42528 emergency room visits. B. There appears to be an ongoing decrease in the number of laryngeal injuries due to auto accidents, while knife and gun injuries continue to increase. C. Historically, older people were considered to be at higher risk for laryngeal fractures due to the increased calcification in the laryngeal skeleton. This does not appear to hold up - the vast majority of laryngeal injuries occur in young adults. D. Women have been presumed to be at increased risk for supraglottic injuries due to their longer and more slender necks. Relatively few females suffer laryngeal injuries, but there has not been any documented increase in injury at this specific site. Anatomic Considerations A. The larynx lies in a relatively protected anatomic position. 1. The mandible, sternum and clavicles protect the larynx anteriorly. Cervical vertebrae protect posteriorly. 2. Thyroid cartilage shields glottis. B. The hyoid, although not a part of the larynx, is important due to its close relationship with the larynx. Thyrohyoid membrane attaches superior cornu of thyroid cartilage to hyoid. C. The thyroepiglottic ligament connects the epiglottis to the thyroid cartilage just superior to the anterior commissure. D. Extrinsic muscles are divided into elevators (digastric, stylohyoid, geniohyoid, mylohyoid) and depressors (thyro- sterno- and omohyoid) E. The intrinsic muscles of the larynx are paired - with the exception of the interarytenoid. All are innervated by the recurrent branch of the laryngeal nerve except the cricothyroid which is innervated by the superior laryngeal. The posterior cricoarytenoid is the major abductor of the vocal cords. Pediatric Considerations A. Several unique anatomical factors are important regarding children and laryngeal trauma: 1. Advantages of pediatric larynx a. Increased flexiblity of cartilage - Calcification increases risk of fracture - But children more susceptible to soft tissue injury. b. Located higher in neck - Protected more by mandible c. Larynx is more mobile - More resistive to dislocations 2. Disadvantage of pediatric larynx a. Relatively smaller diameter - Tolerates less edema and stenosis - Predisposes to bad outcome from laryngeal trauma b. Uncooperative patients - More difficult exam - Tracheotomy under local not tolerated - Use inhalation technique, bronchoscopic airway control with trach team ready B. Children suffer different types of injury as a result of the above. Soft tissue edema and inflammation, telescoping injuries, arytenoid dislocations, laryngeal collapse, and TVC paralysis were remarkable in small series (10 patients) reported by Myer. Particular care should be exercised in the recognition of telescoping injuries. Because of its position, the cricoid is frequently dislocated superiorly under the thyroid cartilage. Mechanism of Injury A. Blunt External Trauma is the most common cause of laryngeal stenosis (failure to reduce dislocated or fractured cartilage), and the second most common cause of death in head and neck trauma. 1. The overall incidence low - 0.34 - 0.5% of trauma patients. 2. Schaefer reports 68 patients admitted with acute laryngeal trauma in 10 years (total ER visits - 157,000/year) 3. Injury occurs when forward motion is decelerated, and the larynx of an extended neck is crushed between the rigid cervical vertebrae and object against which the patient decelerates, with mucosal shearing and damage to underlying cartilaginous support. - Motor vehicle accidents - Motorcycle accidents - Sports injuries - Biking injuries 4. Sustained low velocity force - i.e. strangulation - can cause serious cartilage damage without crepitus, mucosal tears (no hemoptysis) or airway compromise (no hoarseness or stridor). If not repaired may cause permanent morbidity. a. Line reported on 171 strangulation victims - only one was felt to have a life threatening airway injury. Death was usually secondary to non-airway etiology (Vascular constriction, spinal cord injury, carotid sinus stimulation, etc.) b. Females were more likely to have fractures than males, and a hyoid bone fracture was most common, followed by thyroid cartilage fracture B. Blunt Internal Trauma 1. Intubation Trauma - as well as laryngoscopy and bronchoscopy a. Contributing factors - Poor visualization prior to attempt - Misdirected tube (poor technique) - Oversize tube - Local infection b. Best treatment is prevention c. Classes of injury i. Supraglottic - edema, laceration, hematoma ii. Glottic - ulcer or granuloma, damaged TVC, arytenoid dislocation iii. Subglottic - Lacerations from protruding obturator 2. Endotracheal tubes and tracheostomy tubes a. Contributing factors - Oversized - Time left in place - Cuff inflation pressures - Movement of tube (positive pressure ventilation, poor fixation, repositioning of head, coughing or "bucking") - Systemic factors (diabetes, hypotension, steroid dependency, infections) b. Can cause circumferential damage c. Most commonly affects interarytenoid area, medial surface of arytenoids, and anterolateral aspect of cricoid. d. May rarely cause cord paralysis - Cavo proposes the site of recurrent nerve injury to be about 6 to 10 mm below the posterior third of the true cord, where an over-inflated cuff may compress the anterior branch of the nerve against the overlying thyroid cartilage. - The anterior branch innervates adductors - so hoarseness as opposed to airway distress would be seen. - Brandwein identified a case of bilateral cord paralysis from intubation - and proposed the site of injury to be the anterior ramus as it passes between the thyroid and arytenoid cartilages. 3. Nasogastric tubes may erode posterior plate of cricoid, causing ulceration, infection and delayed healing. 4. Foreign bodies may cause damage on entry into larynx, while lodged in larynx, or during attempts at removal C. Penetrating Trauma - See penetrating neck trauma Grand Rounds D. Chemical and Thermal Trauma 1. Caustic substances result in mucosal ulceration (2nd and 3rd degree burns). NaOH most common - as well as phenol, KOH, bleach. 2. Most commonly injured areas are the epiglottis, A-E folds, arytenoids and the post cricoid region 3. Wounds heal usually by granulating and may lead to stenosis. 4. Avoid neutralization attempts - exothermic reactions! Also avoid nasogastric tube (risk chondritis, recommend gastrostomy tube) 5. Thermal trauma is a relatively uncommon consequence of burn injuries - only 2 to 3% of burn patients. Most have suffered >50% TBSA burns. 6. Thermal trauma is much more often upper airway than lower airway, because of: a. The natural cooling capacity of the mucosa of the upper airway b. Reflex closure of the glottis - Moritz showed in dogs that only when the TVC were stented open could enough heat be delivered to cause significant lower airway injury. 7. An exception to the rule is inhaled steam - the heat carrying capacity is much greater than dry air, and even apparently minor steam inhalations may result in severe lower airway injury. 8. Singed nasal hair, carbonaceous sputum, hoarseness, wheezes and rales on PE in a burn victim should heighten suspicion. Care must be taken in diagnosis, as patients initially examined while hypovolemic may not have the ability to develop the characteristic edema. Acute Management of Patient A. Secure Airway 1. Must be established without flexion or extension of neck due to the possibility of coexistent spinal injury. 2. Although there continues to be some debate, most otolaryngologists agree that tracheotomy is the preferred modality if the airway is compromised or there is known extensive laryngeal injury. Reece reported that 76% of patients with attempted oral or nasal intubation had worsened respiratory difficulty. Gussack, however feels there maybe a place for intubation when it can be done under direct vision. Others advocate bronchoscopic control of airway in controlled environment when possible. 3. Blind intubation is to be avoided if laryngeal injury possible. 4. Cricothyrotomy does not guarantee airway if cricothyroid separation has occurred, and may contribute to the injury. 5. As a rule, the airway should be secured by the least traumatic method possible. B. Stabilize life-threatening injuries - Angood 1986 noted that 75% had serious multisystem trauma. C. C-Spine survey with neurologic assessment and placement of immobilizer until cleared. D. Rule out Esophageal Perforations 1. Gastrograffin (water soluble) contrast study or esophagoscopy 2. Methylene blue at surgery to demonstrate leak 3. Prompt operative intervention for perforations with closed suction drainage E. Further Evaluation of Laryngeal Injury 1. Indirect laryngoscopy being replaced by fiberoptic exam - better tolerated and gives superior visualization. Perform as early as possible 2. Laryngeal tomos and laryngograms obsolete. The diagnostic procedure of choice is CT scan. Schaefer recommends scans when the result would influence treatment decisions - that is, no reason for CT when history and presentation clearly indicate the need for operative intervention or no intervention. Others should get scans to evaluate the laryngeal skeleton, cricoarytenoid joints and endolaryngeal soft tissue. F. Evaluation of Associated Injuries 1. Cervical spine fracture or dislocation - Must not flex or extend neck - Neurologic survery 2. Vascular injury - Expanding hematoma - Hypovolemia - Arteriography to determine site 3. Esophageal and pharyngeal injuries - Oral exam - Avoid NG tube 4. Lower respiratory tract injuries - Pneumo thorax (breath sounds, CXR) - Bronchial tears Diagnosis of Acute Laryngeal Trauma A. History 1. Progressive dyspnea, hypoxemia, stridor is common and suggests impending airway compromise 2. Voice changes (hoarseness to aphonia) may occur secondary to edema or TVC damage 3. Hemoptysis strongly suggests intralaryngeal laceration 4. Odynophagia, dysphagia may be due to hypopharyngeal lacerations or hyoid fracture 5. Pain is a variable indicator and may radiate to the ears 6. Severe injury may be well tolerated for 24-48 hours before symptoms arise * a. Angood notes up to 1/3 have minimal symptoms on presentation. b. Snow reported a case of a motorcyclist with complete tracheal separation and bilateral cord paralysis who walked several miles to get help B. Physical Exam 1. Crepitus, subcutaneous emphysema suggests fracture but can also be associated with ruptures of hypopharynx or esophagus, or from the mediastinum secondary to a ruptured bronchus 2. Palpable fracture, dislocation, or discontinuity 3. Loss of normal contour of larynx, loss of prominence of thyroid or cricoid cartilages 4. Localized tenderness 5. Echymosis or swelling of anterior neck 6. External signs may be minimal with even major laryngeal injury. C. Laryngoscopy 1. IDL to evaluate cord mobility, mucosal edema, lacerations, exposed cartilage, dislocations, fractures or hematomas. Now largely replaced by: 2. Fiberoptic laryngoscopy which as previously noted requires less patient cooperation and no need to move neck while providing superior visualization 3. Supraglottic edema may hide distal injuries D. Imaging Studies 1. CT Scan - imaging procedure of choice, provides cross sectional view of anatomy, excellent visualization of cartilage and soft tissue 2. CT indicated to evaluate injured larynx that lacks clear indications for exploration (mucosal edema and/or hematoma with questionable fracture or dislocation). Also helpful to evaluate severe injury when major surgery indicated, and to evaluate adequacy of repair. 3. Cervical Spine Series 4. Chest X-ray - look for pneumothorax, mediastinal injury or rib and sternal injuries 5. In most cases the clinical assessment - not the imaging studies - determines if a surgical procedure is indicated. Management of Acute Laryngeal Trauma A. Basic Principles of Management 1. Recognition of the injury requires a high index of suspicion - mechanism of injury, other head and neck trauma (maxillofacial fracture, first rib fracture, sternum fracture, etc.) a. Make a deliberate search for laryngeal injury b. May be disguised by rapid (successful) intubation as part of resuscitation effort, to be uncovered upon extubation 2. Maintenance of airway - Must continue to be top priority 3. Define the injury perform laryngoscopy after airway is secured. Injuries noted in a series by Pennington included: a. Thyroid cartilage fracture (midline, vertical) 81% b. Rupture of thyroepiglottic ligament 50% c. Severe mucosal tears (TVC, ventricle, etc.) 45% d. Laryngotracheal separation 18% e. Pyriform and esophageal tears 13% 4. Indicators of a poor prognosis include: a. Early airway obstruction b. Exposed cartilage c. Cartilage fracture d. TVC immobility 5. Early anatomical restoration a. Most authors support early repair (<24 hours), decreased incidence of stenosis, over delayed repair to allow resolution of edema b. Delay is associated with increased failure of decannulation, poor speech recovery, increased risk of aspiration. c. In severe multiple trauma patient, delay may be unavoidable, repair should be done as soon as stabilized. 6. Conservative management may be indicated with minor hematomas, lacerations, edema without airway obstruction. Therapy includes voice rest, bed rest with elevated HOB, humidification 7. Adjuvant Therapy a. Antibiotics - Cephalosporins are indicated with lacerations (particularly hypopharyngeal), most recommend 5-10 days post-operatively b. Steroids - No good studies of efficacy - if used, should be given as early as possible - preferably at the time of the injury. c. Vitamins and minerals promote healing of larynx d. Tetanus toxoid e. Racemic epinephrine B. Classes of Injury 1. Supraglottic injury is typically associated with fracture of thyroid cartilage and hyoid bone, and is said to be more common in patients with long, thin necks a. Prominent symptoms i. Muffled voice ii. Stridor iii. Odynophagia (hyoid injury, hypopharyngeal injury) b. Prominent findings i. Posterior and superior displacement of epiglottis (secondary to tearing of thyroepiglottic ligament) obscuring view of the anterior commisure on laryngoscopy ii. Normal TVC mobility iii. Anterior commisure normal once visualized iv. Loss of prominence of thyroid cartilage notch v. Vertical tears of hypopharyngeal mucosa vi. Crepitus not uncommon c. Contamination and infection are common d. Often severity is missed by positioning of laryngoscope against epiglottis resulting in correction of posterior displacement of torn epiglottis. 2. Glottic injuries typically involve fracture of thyroid cartilage (vertical) in area of attachment of TVC at anterior commissure a. Prominent symptoms i. Poor voice ii. Airway obstruction iii. Hemoptysis b. Prominent findings i. TVC edema, distortion ii. Disrupted anterior commissure with decreased anterior-posterior diameter iii. Abnormal cord mobility 3. Subglottic injuries are typically associated with fracture of cricoid cartilage, and are more common in patients with short necks a. Prominent symptoms i. Early dysphagia ii. Hoarseness not a prominent symptom b. Prominent findings i. Loss of cricoid prominence ii. Subglottic edema and narrowing on DL iii. Possible associated RLN injury 4. Tracheal avulsion or disruption typically occurs at level of first tracheal ring, associated fracture of cricoid cartilage a. Prominent symptoms i. Airway obstruction ii. Crepitus iii. Hemoptysis - May be surprisingly asymptomatic b. Prominent findings i. Bilateral TVC paralysis (RLN injury) ii. Blood distally on DL iii. Palpable dislocation c. Distal trachea may be retracted into upper mediastinum 5. Combined Injuries - Laryngeal trauma typically presents with a combination of above with combination of symptoms and findings. Commonly associated injuries include: a. Cricoarytenoid dislocation i. Pain, hoarseness ii. Arytenoid appears tipped forward and rotated medially, TVC appear bowed and flaccid iii. Palpate joint on DL (decreased mobility) b. Hyoid bone fracture i. Pain on protrusion of tongue ii. Edema and hematoma common iii. Central body is most common area of fracture iv. Usually visible on X-ray C. Surgical Exploration and Repair 1. Indications for surgery a. Vocal cord paralysis b. Mucous membrane lacerations c. Arytenoid dislocation d. disruption of structural stability - Cartilage exposure e. Other criteria (Biller 1985) - Progressive subcutaneous emphysema - Airway obstruction requiring tracheostomy - Exposure of cricoid cartilage D. Treatment of Specific Injuries 1. Lacerations in mucosal membranes - Untreated mucosal loss may lead to superficial infection, perichondritis, granulation tissue, and laryngeal distortion a. Lacerations seen on IDL demands at least DL b. Primary closure with 5-0 or 6-0 absorbable suture c. Local advancement flaps from aryepiglottic fold and epiglottis to cover defects d. Grafts from buccal mucosa, split thickness skin and dermis for larger defects 2. Cartilage fracture and dislocation a. In general i. Transverse skin incision ii. Avoid transection of strap muscles - May be useful in reconstruction - May be needed for support iii. Mid-line thyrotomy - May utilize fracture line in some cases iv. Restore cartilages to normal alignment - elevate from depressed position and fix with wire suture v. Remove free cartilage fragments that are devoid of pericondrium - Prevents foreign body reaction - Controversial - emphasize importance of saving all cartilage b. Stents - Endolaryngeal stenting is reserved for wounds involving disruption of the anterior commissure, comminuted laryngeal skeletal fractures,and massive mucosal injuries. Stents are used to maintain positioning and provide support for unstable cartilage fractures, prevent web formation in anterior commissure injury. Ideal characteristics of stent i. Avoid rigid materials that increase mucosal trauma ii. Fixation in such a way that it moves with the larynx during swallowing iii. Consistently recoverable at endoscopy without further traumatizing the larynx c. Stabilized with wire suture to external buttons, with closed endoscopic removal d. Most authors recommend early removal at 10-14 days e. Previously left for up to 12 months (associated with higher morbidity) 3. Cricoarytenoid dislocation a. Reposition endoscopically by direct manual palpation - posterior, lateral, superior pressure. b. Occasionally anterior pressure with anterior commissure scope will facilitate repositioning c. Requires early repositioning - < 14 days d. A lateral blow may squeeze the arytenoid between the thyroid ala and c-spine and result in a degloving type injury to the arytenoid. The arytenoid is exposed through an irregular laceration and may or may not be dislocated. Wound repair principles as above are applicable, and if necessary, attempt to reduce the arytenoid should be made. As a rule, repair of degloving injury without dislocation results in good voice and mobile TVC. TVC mobility is unlikely to return if there is coexistent dislocation. 4. Hyoid fracture a. Repair usually not necessary in isolated fractures unless dysphagia persists b. May repair by direct wiring or may remove central fractured segment 5. Torn epiglottis a. Posterior displacement from torn thyroepiglottic ligament b. Excise torn tissue, do not try to repair 6. Tracheal avulsion or disruption - suprahyoid release and cervicothoracic mobilization will allow closure of up to a 5-6 cm gap a. Upper trachea - Low tracheotomy - Reanastomose lower to proximal segment of trachea or cricoid cartilage (steel sutures) b. Lower trachea - End to end anastomosis - Trach above or below depending on injury 7. Recurrent laryngeal nerve injury a. May be temporary - for example paresis from intubation generally resolves. b. If no return by eight weeks, consider decompression or repair i. Primary Repair - 9-0 nylon suture of epineurium under microscopic control - Rarely successful due to complex anatomy ii. Implantation of avulsed nerve into posterior cricoarytenoid muscle - Generally accepted iii. Arytenoidectomy for bilateral permanent, non-responsive TVC paralysis Treatment Results A. Leopold summarized 200 cases of laryngeal trauma in 1983 and analyzed these with regard to treatment and outcome: 1. Cases managed conservatively (medically) did better than those which required surgical intervention. Cases treated medically were admittedly less severe. 2. Airway and voice results were better in those operated on within 24 hours when surgery was necessary. 3. The need for a stent was a poor prognostic indicator both regarding voice and airway. 4. Immobile vocal cords prior to operative intervention gave a considerably poorer prognosis both for airway and voice result. 5. Stenting for best results should be left for 2 to 3.5 weeks. Treatment Protocols A. Treatment Based on Injury Classification 1. Group 1 Finding: Minor hematoma or lacerations, no fractures Management: Conservative - elevate HOB, humidification, voice rest, (+/-) steroids, (+/-) antibiotics, (+/-) CT to confirm integrity of cartilage 2. Group 2 Finding: Hematoma, edema, laceration without exposed cartilage Management: Tracheotomy, DL, CT scan (if DL inconclusive or limited) 3. Group 3 Finding: Massive edema, large mucosal tears, exposed cartilage, TVC immobility, displaced cartilage fracture Management: Tracheotomy, DL, exploration, repair 4. Group 4 Finding: As in Group 3 Management: As in Group 3 Repair requiring a stent or keel ------------------------------------------------------------------------------- BIBLIOGRAPHY 1. Angood PB et al. Extrinsic Civilian Trauma to the Larynx and Cervical Trachea - Important Predictors of Long-term Morbidity. The Journal of Trauma 1986, 26(10):869-873. 2. Berman JM. Diagnosis of Laryngeal Trauma. Ear, Nose, & Throat Journal 1981, 60:352-355. 3. Biller HF, Lawson W. Management of Acute Laryngeal Trauma, in Bailey BJ & Biller HF: Surgery of the Larynx, Saunders, 1985:149-154. 4. Brandwein, M et al. Bilateral Vocal Cord Paralysis Following Endotracheal Intubation. Archives Otolaryngology 1986, 112:877-882. 5. Cavo, JW. True Vocal Cord Paralysis Following Intubation. Laryngoscope 1985, 95:1352-59. 6. Close, LG et al. Cricoarytenoid Subluxation, Computed Tomography, and Electromyographic Findings. Head and Neck Surgery 1987, 9:341-348. 7. Gaynor,EB. Gastroesophageal Reflux as an Etiologic Factor in Laryngeal Complications Of Intubation. Laryngoscope 1988, 98:972-79. 8. Gussack,GS et al. Laryngotracheal Trauma: A Protocol Approach to A Rare Injury. Laryngoscope 1986, 96:660-665. 9. Kennedy KS, Harley EH. Diagnosis and Treatment of Acute Laryngeal Trauma. Ear, Nose, & Throat Journal 1988, 67:584-602. 10. Leopold DA. Laryngeal Trauma: A Historical Comparison of Treatment Methods. Archives of Otolaryngology 1983, 109:106-112. 11. Line WS et al. Strangulation: A Full Spectrum of Blunt Neck Trauma. Ann Otol Rhinol Laryngol 1985, 94:542-546. 12. Miller, RP et al. Airway Reconstuction Following Laryngotracheal Thermal Trauma. Laryngoscope 1988, 98:826-29. 13. Myer CM et al. Blunt Laryngeal Trauma in Children. Laryngoscope 1987, 97:1043-1048. 14. Myers EM, Iko BO. The Management of Acute Laryngeal Trauma. The Journal of Trauma 1987, 27(4):448-452. 15. Schaefer SD. Primary Management of Laryngeal Trauma. Ann Otol Rhinol Laryngol 1982, 91:399-402. 16. Schaefer SD, Brown OE. Selective Application of CT in the Management of Laryngeal Trauma. Laryngoscope 1983, 93:1473-1475. 17. Schaefer SD, Close LG. Acute Management of Laryngeal Trauma Update. Ann Otol Rhinol Laryngol 1989, 98:98-104. 18. Schaefer, SD. The Treatment of Acute External Laryngeal Injuries 'State of the Art'. Archives Otolaryngology - Head and Neck Surgery 1991, 117:35-39. 19. Snow JB. Diagnosis and Therapy for Acute Laryngeal and Tracheal Trauma. Otolaryngologic Clinics of North America 1984, 17(1):101-106. 20. Stanley RB. Value of Computed Tomography in Management of Acute Laryngeal Injury. The Journal of Trauma 1984, 24(4):359-362. 21. Stanley,RB and Colman, MF. Unilateral Degloving Injuries of the Arytenoid Cartilage. Arch Otolaryngology - Head and Neck Surgery 1986, 112:516-18. ------------------------------END--------------------------------------------