Comparison of Ultrasound, Radiography, and Clinical Investigations in the Diagnosis of Early Rheumatoid Synovitis in Patients with Nonspecific Musculoskeletal Symptoms: A Multicenter Cross-Sectional Study.

BACKGROUND Early diagnosis and treatment of rheumatoid synovitis can reduce the progression of rheumatoid arthritis (RA). However, in the early stages of rheumatoid synovitis, patients may only have non-specific musculoskeletal symptoms, and plain film radiographs may not detect early synovial changes. The aim of this study was to compare the sensitivity and specificity of ultrasound with radiography, and clinical investigations in the detection of rheumatoid synovitis in patients presenting with nonspecific musculoskeletal symptoms. MATERIAL AND METHODS This was a non-randomized, cross-sectional, clinical study that included 189 patients who had nonspecific musculoskeletal symptoms. All patients underwent clinical investigations, postero-anterior and dorsal radiographic imaging, and bilateral grey-scale ultrasound examinations of the third and second metacarpophalangeal (MCP) joints, the third and the second proximal interphalangeal (PIP) joints, the second and the fifth metatarsophalangeal (MTP) joints, and the wrist. RESULTS There was no clear predictive value for detection of early synovitis by clinical investigations alone. Plain film radiography of patients only provided accurate information of joint erosions but less information for synovitis. Grey-scale ultrasound was more effective at detecting early synovitis compared with clinical investigations (p=0.00015; q=4.548) and compared with plain film radiography (p=0.0002; q=4.537), and quantified the synovial changes. The predictive values of plain film radiography and clinical investigations had 0.43 and 0.24 sensitivity and 0 specificity compared with ultrasound. CONCLUSIONS The findings of this study support the use of grey-scale ultrasound in the detection of early rheumatoid synovitis of the fingers and the wrist.