Cricothyroid joint abnormalities in patients with rheumatoid arthritis.

The objective of this study was to assess structural and functional abnormalities of the cricothyroid joint (CTJ) in patients with advanced rheumatoid arthritis (RA). A total of 19 subjects--11 patients with advanced RA and eight normal controls--were considered. All subjects underwent laryngeal endoscopy, acoustic analysis, and high-resolution computerized tomography (HRCT). Vocal symptoms, such as hoarseness, loss of range, vocal fatigue, and dyspnea were inquired and acoustic parameters, mainly pitch range, fundamental frequency, habitual pitch, perturbation parameters, and noise-to-harmonic ratio (NHR) and voice turbulence index were measured. Frequencies and means were calculated for categorical and continuous variables. Cases and controls were compared with respect to acoustic analysis, HRCT findings and laryngeal symptoms using nonparametric tests, Mann-Whitney U test for continuous variables and Fishers exact test for categorical variables. Almost half of the patients with RA had loss range and two-thirds had vocal fatigue. Thirty-six percent experienced hoarseness compared with 25% in the control group. 9.1% had decrease in vocal fold mobility and 27% had moderate/severe edema of the vocal folds/arytenoids compared with none in the control group. HRCT showed narrowing in the CTJ in 81.8% and ankylosis in 9.1% compared with none in the control group. 45.5% had an increase in the CTJ density compared with 12.5% in the control group. Acoustic analysis revealed significant decrease in pitch range and maximum phonation time (MPT) and significant increase in perturbation parameters. CTJ is commonly affected in patients with RA. Functional disabilities are crucial especially in professional voice users. Proper awareness is important for early detection and intervention.