Diagnostic utility of musculoskeletal ultrasound in patients with suspected arthritis – a probabilistic approach

Abstract

IntroductionThis study aimed to assess the utility of musculoskeletal ultrasound (MSUS) in patients with joint symptoms using a probabilistic approach.MethodsOne hundred and three patients without prior rheumatologic diagnosis and referred to our clinic for evaluation of inflammatory arthritis were included. Patients were assessed clinically including joint examination, laboratory testing including acute-phase reactants, rheumatoid factor (RF) and anti citrulinated protein antibody (ACPA), and radiographs of hands and feet if clinically indicated. A diagnostic assessment was then performed by the responsible rheumatologist where the probability of a) any inflammatory arthritis and b) rheumatoid arthritis was given on a 5-point scale ranging from 0 to 20% up to 80 to 100% probability. Subsequently, an ultrasound examination of the wrist, metacarpophalangeal (MCP), proximal interphalangeal (PIP) joints 2 to 5 in both hands, metatarsophalangeal (MTP) joints 2 to 5 in both feet and any symptomatic joints was performed and the results presented to the same rheumatologist. The latter then assessed the diagnostic probabilities again, using the same scale.ResultsThe rheumatologists’ certainty for presence/absence of inflammatory arthritis and rheumatoid arthritis was increased significantly following ultrasound performance. The proportion of patient for whom diagnostic certainty for inflammatory arthritis was maximal was 33.0% before and 71.8% after musculoskeletal ultrasound (P <0.001). With regard to a diagnosis of RA, the proportions were 31.1% pre-test and 61.2% post-test (P <0.001). MSUS findings agreed with the final diagnosis in 95% of patients.ConclusionMusculoskeletal ultrasound, when added to routine rheumatologic investigation, greatly increases the diagnostic certainty in patients referred for the evaluation of inflammatory arthritis. The changes from pre-test to post-test probability quantify the diagnostic utility of musculoskeletal ultrasound in probabilistic terms.

2016 update of the EULAR recommendations for the management of early arthritis

“…Synovitis and erosion detected by MRI or US may predict further joint damage in early arthritis, but false positivity has been reported 26 35. MRI-detected bone marrow oedema and osteitis are independent predictors of radiographic progression in early RA,23 24 but data are limited in early arthritis.…”

The relevance of ultrasound examination of the foot and ankle in patients with rheumatoid arthritis – a review of the literature

“…Also, the presence of US erosions and PD positive synovitis in patients with early arthritis (including RA) is predictive for subsequent radiographic damage [8,9]. The utilization of US in patients presenting with inflammatory arthritis classified as RA by a rheumatologist, has significantly increased the diagnosis certainty [10]. Compared to magnetic resonance imaging (MRI), US is equally sensitive in the detection of synovitis and superior in the detection of tenosynovitis, but is inferior in the detection of bone erosions in the small joints of the hand and foot [11].…”

Clinical Applications of Superb Microvascular Imaging in the Liver, Breast, Thyroid, Skeletal Muscle, and Carotid Plaques

“…Musculoskeletal disorders are very common in patients with severe or unclear joint symptoms, and the traditional evaluation primarily includes a medical history and physical examinations. 39 Musculoskeletal US can monitor angiogenesis within musculoskeletal soft tissues and facilitate the evaluation of disease activities. 40 In recent studies, SMI was used to assess arthritis, lateral epicondylitis, and carpal tunnel syndrome (CTS).…”