title: A novel approach to cricoarytenoid joint injections: An anatomic study.
abstract: To demonstrate a novel approach to cricoarytenoid joint (CAJ) injections.
  
  
  
  Anatomic feasibility study.
  
  
  
  Five human cadaveric larynges providing 10 CAJ s were used to obtain trajectory measurements of a 27-gauge 1½-inch needle placed between the CAJ capsule and the contralateral cricothyroid membrane. Ten additional larynges providing 20 CAJ s were then used to assess the efficacy of applying the previously obtained measurements to guide 0.2-cc methylene blue injections of the CAJ using a 27-gauge 1½-inch needle. Successful injection was confirmed by direct visualization of methylene blue within the CAJ capsule.
  
  
  
  The tip of the needle made a 70 ± 1.87 degree (confidence interval [CI] 95%) angle relative to the plane parallel to the anterior lamella of the cricoid cartilage; the needle was within the cricothyroid membrane 5 ± 0.77 mm (CI 95%) lateral to the midsagittal plane; the needle was 4 ± 0.80 mm (CI 95%) anteroinferior from the vocal process of the arytenoid cartilage as measured within the airway; and the distance from the point of airway entry and the CAJ capsule was 17 ± 2.42 mm (CI 95%). Twenty CAJ injections were attempted using the guidelines established here with an 85% success rate.
  
  
  
  The current approach to CAJ injection utilizes microlaryngoscopy in an operative setting. This study is the first to describe the accessibility of the CAJ through percutaneous injection using reliable landmarks, potentially allowing access to the joint in an office-based setting.
  
  
  
  NA Laryngoscope, 127:199-203, 2017.
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Texas Health Science Center at San Antonio, San Antonio, Texas, U.S.A.
authors.forename: Sunthosh
authors.initials: S
authors.lastname: Sivam
authors.affiliation: Bulverde Centre for Emergency Health Sciences, Bulverde, Texas, U.S.A.
authors.forename: Alison
authors.initials: A
authors.lastname: Burkett
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, University of Texas Health Science Center at San Antonio, San Antonio, Texas, U.S.A.
authors.forename: C Blake
authors.initials: CB
authors.lastname: Simpson
mesh_terms: D059925:Anatomic Landmarks; D001193:Arytenoid Cartilage; D002102:Cadaver; D003413:Cricoid Cartilage; D005240:Feasibility Studies; D006801:Humans; D007267:Injections; D007828:Laryngoscopy / Q000379:methods
keywords: Cricoarytenoid joint; percutaneous injection; rheumatoid arthritis