Drs. Gutierrez and Di Geso contributed equally to this work.
Special Theme Article: Clinical Imaging and the Rheumatic Diseases
Ultrasound Detection of Cartilage Calcification at Knee Level in Calcium Pyrophosphate Deposition Disease
Version of Record online: 24 DEC 2013
Copyright © 2014 by the American College of Rheumatology
Arthritis Care & Research
Volume 66, Issue 1, pages 69–73, January 2014
How to Cite
Gutierrez, M., Di Geso, L., Salaffi, F., Carotti, M., Girolimetti, R., De Angelis, R., Filippucci, E. and Grassi, W. (2014), Ultrasound Detection of Cartilage Calcification at Knee Level in Calcium Pyrophosphate Deposition Disease. Arthritis Care Res, 66: 69–73. doi: 10.1002/acr.22190
- Issue online: 24 DEC 2013
- Version of Record online: 24 DEC 2013
- Accepted manuscript online: 7 OCT 2013 12:28PM EST
- Manuscript Accepted: 24 SEP 2013
- Manuscript Received: 10 MAR 2013
To determine the sensitivity, specificity, and accuracy of ultrasound (US) in the detection of cartilage calcification at knee level in patients with calcium pyrophosphate deposition disease (CPDD) and to assess the interobserver reliability.
Seventy-four CPDD patients and 83 controls with other chronic arthritis were included. All patients underwent a clinical examination, synovial fluid analysis, and radiographic assessment of the knee. US examinations were performed in order to detect hyperechoic spots within the hyaline cartilage layer and hyperechoic areas within the meniscal fibrocartilage. Twenty patients were assessed by 2 operators in order to calculate the interobserver reliability.
A total of 314 knees in 157 patients (74 with CPDD, 19 with rheumatoid arthritis, 17 with spondyloarthritis, 32 with osteoarthritis, and 15 with gout) were assessed. In the 74 patients with CPDD, hyaline cartilage spots were detected by US in at least 1 knee in 44 patients (59.5%), whereas radiography detected hyaline cartilage spots in 34 patients (45.9%) (P < 0.001). Meniscal fibrocartilage calcifications were detected by US in 67 of the 74 CPDD patients (90.5%), whereas conventional radiography detected calcifications in 62 patients (83.7%) (P = 0.011). The criterion validity expressed as percentage of sensitivity, specificity, and accuracy of US in the detection of articular cartilage calcification was high. Both kappa values and overall agreement percentages showed moderate to excellent agreement.
US is an accurate and reliable imaging technique in the detection of articular cartilage calcification at knee level in patients with CPDD.