Ultrasound of the hands and feet for rheumatological disorders: influence on clinical diagnostic confidence and patient management

The purpose of the study was to quantify the impact that ultrasound (US) of the hands and feet has on the rheumatologists' diagnostic confidence and on patient management. There were 62 consecutive referrals from two rheumatologists for US of the hands and/or feet for this prospective controlled observational study. Measurements of diagnostic confidence for both specific clinical findings as well as overall diagnosis using a Likert scale were made both before and after the US examination in each case. Proposed management was also recorded before US and then with the benefit of the US result. McNemar's test was performed to determine differences in diagnostic certainty and proposed management before and after US. The physician certainty for specific clinical findings increased significantly following US for synovitis (9.7 vs 38.7%), tenosynovitis (9.7 vs 46.8%), erosions (1.6 vs 58.1%), enthesitis (50.0 vs 83.9%) and other (53.2 vs 77.4%). The physician certainty for overall diagnosis increased significantly for seronegative arthritis (46.8 vs 61.3%), inflammatory osteoarthritis (46.8 vs 87.1%), and primary osteoarthritis (46.8 vs 73.0%). A total of 88.7% of patients had disease-modifying antirheumatic drugs as a proposed management option before US vs 48.4% after US. Before US, 4.8% of patients had non-steroidal anti-inflammatory drug as a proposed management option versus 45.2% after US. Ultrasound of the hands and/or feet significantly influenced the rheumatologists' diagnostic confidence in specific clinical findings and management plans.