From the Guidelines
MRI arthrogram is generally considered the best imaging modality for evaluating the biceps tendon, particularly for detecting subtle tears, partial tears, and instability. The arthrogram technique involves injecting contrast material into the joint before the MRI, which helps highlight and better visualize the biceps tendon and its surrounding structures. This enhanced visualization is especially valuable for evaluating the intra-articular portion of the long head of the biceps tendon, the biceps labral complex, and the bicipital groove. While a regular MRI can adequately assess complete tears and significant pathology of the biceps tendon, it may miss smaller lesions or partial tears that an arthrogram would detect.
The choice between these modalities should consider the specific clinical suspicion, as MRI arthrogram is more invasive and typically reserved for cases where there is a high suspicion of subtle biceps pathology or when regular MRI results are inconclusive but clinical symptoms persist. According to a study by 1, MRI is particularly useful in the assessment of biceps tears, with improved sensitivity for the detection of partial tears of the biceps and triceps tendons. Another study by 1 reported sensitivity and specificity of 92.4% and 100%, respectively, in detecting distal biceps tendon ruptures and 59.1% and 100%, respectively, for partial tears.
However, it's worth noting that ultrasound (US) can also be useful for detection of biceps tendon abnormalities, with reports showing 95% sensitivity, 71% specificity, and 91% accuracy for the diagnosis of complete versus partial distal biceps tendon tears with US, as mentioned in 1. Nevertheless, the improved diagnostic accuracy of MRI arthrogram is due to the contrast material distending the joint and outlining structures that might otherwise be difficult to distinguish on standard MRI sequences, making it the preferred choice for evaluating the biceps tendon.
Some key points to consider when choosing between MRI arthrogram and regular MRI include:
- The specific clinical suspicion and the need for detailed visualization of the biceps tendon and its surrounding structures
- The potential for subtle tears or partial tears that may be missed by regular MRI
- The invasiveness of the MRI arthrogram procedure and the potential risks and benefits associated with it
- The availability and expertise of the imaging modalities and personnel.
Ultimately, the choice between MRI arthrogram and regular MRI should be based on a careful consideration of these factors and the individual patient's needs and circumstances.
From the Research
Comparison of MRI Arthrogram and Regular MRI for Biceps Evaluation
- The choice between MRI arthrogram and regular MRI for evaluating the biceps depends on the specific condition being assessed and the associated diagnoses that need to be considered 2.
- For the diagnosis of complete tears of the long head of the biceps tendon (LHBT), MRI shows high specificity, ranging from 93.0 to 99.0%, but diagnostic sensitivity is more heterogeneous, ranging from 55.9 to 90.0% 3.
- MRI arthrogram is particularly useful for assessing associated diagnoses such as full- and partial thickness tears of supraspinatus and subscapularis tendons, pulley lesions, and adhesive capsulitis (frozen shoulder), as well as superior labral anterior posterior (SLAP) lesions 2.
- In the diagnosis of partial tears and/or tendinosis of the LHBT, MRI remains challenging, with a mean sensitivity of 67.8% and specificity of 75.9%, which may warrant complementary clinical examination or other imaging modalities to increase diagnostic confidence in equivocal cases 3.
- A study comparing unenhanced MRI and direct MR arthrography for the evaluation of the intra-articular long head of the biceps brachii tendon found no significant difference between the two modalities for the detection of tendinosis and tears 4.
- However, another study suggested that CT arthrography may be more sensitive and specific than MRI in identifying tendinopathy of the long head of biceps, with a sensitivity of 71.43% and specificity of 100% for CT arthrography, compared to 42.85% and 75% for MRI 5.
- For distal biceps tendon avulsion, MRI has been shown to be more accurate than ultrasonography, with an overall accuracy rate of 80.6% compared to 51.6% for ultrasonography 6.