Assessment of dedicated MRI sequences in the evaluation of the acromioclavicular joint dislocation-A retrospective...

To assess the added value of two additional dedicated MRI sequences in the evaluation of the acromioclavicular ligament complex in patients with traumatic acromioclavicular joint injury.

In this single-center study, shoulder MRIs of post-traumatic patients with suspected acromioclavicular joint dislocation were retrospectively evaluated twice by four readers of varying levels of expertise: once with the standard protocol and once with two additional dedicated acromioclavicular ligament sequences (a proton density-weighted sequence parallel to the acromioclavicular joint and a coronal oblique PD-weighted sequence, with a slice thickness of 2 mm). The acromioclavicular and the coracoclavicular ligaments, along with their different bundles, were analyzed. Intrareader reliability and interreader agreement were assessed by intraclass correlations. Associated shoulder lesions were reported.

A total of 85 shoulder MRIs from patients with acute trauma were retrospectively analyzed (mean age 38.4 ± 13.6 years, male = 73 [85.9%]). Acromioclavicular dislocations were reported in 75 patients (88.2%). The intrareader reliability was good to excellent, ranging from 0.81 to 0.90. Overall, the interreader agreements were excellent (intraclass correlations = 0.93 and 0.94 at both four and six sequences, respectively). The less experienced reader agreed with the more experienced one with and without dedicated acromioclavicular sequences (significant equivalence: t[12] = 2.946, p = 0.006).

In this retrospective cohort, adding dedicated acromioclavicular joint sequences did not show evidence of improvement in the detection and the characterization of potential acromioclavicular ligament lesions, regardless of the reader's level of experience.