Background Numerous studies have clearly demonstrated that USPD examination of joints is more sensitive than clinical physical examination for the detection of synovitis. Further studies are required, however, to determine how specific is this method for the diagnosis and, eventually, to monitor patients with inflammatory joint disease.
Objectives To determine the specificity of wrist and metacarpophalangeal (MCP) joints examination with USPD for the diagnosis of inflammatory joint disease.
Methods The wrist and MCP’s of the dominant hand of 248 subjects (101 fulfilling the 1987 ACR criteria for rheumatoid arthritis and 147 controls - 42 with diagnosis osteoarthritis of the hand as per the ACR criteria and 105 with no identifiable joint disease) were examined for the presence and intensity (grade I-III) of USPD signal. The specificity of this method for the detection of synovitis was obtained with 2x2 tables. The analyses were performed for each joint separately and taking them all together.
Results Among RA patients 79% had positive USPD signal in any of the examined joint while among those patients with non-inflammatory joint disease only 9% had positive USPD signal. In RA patients, USPD signal was more frequently observed in the wrist (66%), MCF2 (66%) and MCP3 (39%). In the control group, USPD signal was more frequently observed in the wrist (9%) and MCP2 (5%). The table below shows the specificity of USPD for inflammatory joint disease at the different joints.
Conclusions This study shows that USPD is a specific method for the diagnosis of inflammatory joint disease and that this is higher with higher signal intensity. When any grade of USPD was examined, the sspecificity for MCP joints is superior compared to the wrist, however, when for grade II and III the specificity of the wrist equal that of the MCPs.
Utility of ultrasound joint counts in the prediction of rheumatoid arthritis in patients with very early synovitis. Andrew Filer, Paola de Pablo, Gina Allen, Peter Nightingale, Alison Jordan, Paresh Jobanputra, Simon Bowman, Christopher D Buckley, Karim Raza. Ann Rheum Dis 2011;70:500–507.
Ultrasonographic assessment of inflammatory activity in rheumatoid arthritis: Comparison of extended versus reduced joint evaluation. E. Naredo, F. Gamero, G. Bonilla, J. Uson, L. Carmona1, A. Laffon. Clinical and Experimental Rheumatology 2005; 23: 881-884.
Disclosure of Interest None Declared