Clinical value of three-dimensional ultrasonography in the morphologic evaluation of rotator cuff tear: a prospective study.

OBJECTIVE: To study the clinical value of three-dimensional ultrasonography (3D-US) in the morphological evaluation of rotator cuff tears (RCTs). METHODS: Based on previously published literature, RCT patterns in our study were divided into crescent, L-shaped with the remnant tendon retracted to the anterior rotator cuff (aL-shaped), L-shaped with the remnant tendon retracted to the posterior rotator cuff (pL-shaped), T-shaped (a tear pattern that is a combination of aL-shaped and pL-shaped), U-shaped, and massive type. Two radiologists prospectively assessed the tear patterns using 3D-US as well as magnetic resonance imaging (MRI) and compared these results using arthroscopy to calculate diagnostic accuracy. RESULT: Fifty-two patients (52 shoulders) were enrolled. The overall diagnostic accuracy of 3D-US in evaluating RCT patterns (82.7%, 43/52; 95% CI: 72.1-93.3%) was significantly higher (p = 0.008) than that of the MRI (57.7%, 31/52; 95% CI: 45.8-73.4%). The accuracy of 3D-US was higher than that of MRI for most types of tears (crescent: 95.0% vs. 55.0%, aL-shaped: 83.3% vs. 77.8%, pL-shaped: 50.0% vs. 25.0%, T-shaped: 75.0% vs. 0.0%, and massive type: 80.0% vs. 100.0%). The accuracies of 3D-US with respect to evaluation by the two radiologists were 84.6% (44/52) and 76.9% (40/52), and there was substantial agreement evident (κ = 0.709). The time taken by the two radiologists to reconstruct the 3D-US images and evaluate the tear pattern was < 5 min. CONCLUSION: The 3D-US can be used for the preoperative evaluation of RCT patterns, and thus be useful for the correct selection of the surgical repair technique for RCTs. KEY POINTS: • Few studies have been found exploring the value of 3D-US for the morphological evaluation of RCTs and correlated with the arthroscopic findings. • Based on previous studies on the morphological classification, anterior L shape (aL-shaped), and posterior L shape (pL-shaped) were used for the first time to describe the torn patterns of RCT.