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To evaluate whether a follow‐up magnetic resonance imaging (MRI) scan performed after initial ultrasound (US) to evaluate soft tissue mass (STM) lesions of the musculoskeletal system provides additional radiologic diagnostic information and alters clinical management. A retrospective chart review was performed of patients undergoing initial US evaluations of STMs of the axial or appendicular skeleton between November 2012 and March 2019. Patients who underwent US examinations followed by MRI for the evaluation of STM lesions were identified. For inclusion, the subsequent pathologic correlation was required from either a surgical or image‐guided biopsy. Imaging studies with pathologic correlations were then reviewed by 3 musculoskeletal radiologists, who were blinded to the pathologic diagnoses. The diagnostic utility of MRI was then assessed on the basis of a 5‐point grading scale, and inter‐reader agreements were determined by the Fleiss κ statistic. Ninety‐two patients underwent MRI after US for STM evaluations. Final pathologic results were available in 42 cases. Samples were obtained by surgical excision or open biopsy (n = 34) or US‐guided core biopsy (n = 8). The most common pathologic diagnoses were nerve sheath tumors (n = 9), lipomas (n = 5), and leiomyomas (n = 5). Imaging review showed that the subsequent MRI did not change the working diagnosis in 73% of cases, and the subsequent MRI was not considered to narrow the differential diagnosis in 68% of cases. There was slight inter‐reader agreement for the diagnostic utility of MRI among individual cases (κ = 0.10) between the 3 readers. The recommendation of MRI to further evaluate STM lesions seen with US frequently fails to change the working diagnosis or provide significant diagnostic utility.

Direct magnetic resonance (MR) arthrography, introduced in 1987, offers enhanced visualization of intra-articular structures through joint distension. Widely recognized for accuracy, it has evolved alongside MRI technology, including 3T MRIs. Guidelines for its use were established in 2023. This article will review technical considerations and articulations in which direct MR arthrography is commonly performed and rely on what technique the literature suggests most between conventional MRI and direct MR arthrogram for the main indications. While 3T MRI competes, direct MR arthrography remains pivotal, especially when conventional MRI results are inconclusive.