This study aimed to see if there was a link between acromial morphology and the position of acromial fractures after reverse shoulder arthroplasty (RSA) and if fracture location and displacement influenced clinical outcomes. Researchers conducted a multicenter retrospective review of RSAs with acromial fractures. Patients with Levy I (n=17) and Levy II (n=25) fractures had their radiographs analyzed to see any differences in acromial morphology, fracture direction, and pattern. The researchers looked at the link between clinical outcomes and fracture location and displacement in patients who had at least a 2-year follow-up. They divided twenty-two patients into two groups based on whether or not they met the American Shoulder and Elbow Surgeons (ASES) minimum clinically significant difference (MCID=20 points). They compared the fracture location and displacement of the groups using metrics such as the acromion-humeral distance (AHD).

The acromial slope of the Levy I group was higher than the Levy II group (127° vs. 117°; p<0.001). Levy type I fractures exhibited a transverse pattern in the coronal plane, whereas, in the sagittal plane, Levy type II fractures showed a diagonal pattern (p<0.001). At the end of the study, 12 of 22 patients (55%) had met the MCID. Those who did not meet the MCID had more fractures that were displaced, as well as a lower AHD (8 vs. 20 mm, p=0.007). Based on the MCID criterion, there was no difference in the distribution of Levy type I and type II fractures (p=0.093). In the Levy I region, a higher acromial slope is linked to transverse fractures, whereas in the Levy II zone, a lower acromial pitch is related to oblique fractures. At mid-term follow-up, 55 % of patients had reached the MCID. Those who did not meet the MCID did poorly after surgery, linked to higher fracture displacement.