As the literature has evolved, the specific location of acromion and scapular spine fractures (ASFs) has become an increasingly important aspect in determining a treatment algorithm for this injury. The Levy Classification (Figure 7-1) was first reported in 2013,¹ which focused on the origin of the deltoid and divided fractures into three zones. A modification of this classification system was introduced in 2022 where regions of the type II zone were subclassified based upon observed clustering of fractures² (Figure 7-2). Type I fractures were defined as fractures through the mid part of the lateral acromion, involving a portion of the anterior and middle deltoid origins. Type IIA fractures were defined as fractures lateral to the glenoid face involving at least the entire middle deltoid origin and at least a portion but not all of the posterior deltoid origin. A type IIB fracture was defined as a fracture in line with the glenoid face involving the entire middle deltoid with a portion but not all of the posterior deltoid origin. A type IIC fracture was defined as a fracture medial to the glenoid face, involving at least the entire middle deltoid with a portion of the posterior deltoid origin. Type III fractures were defined as fractures at the base of the acromion spine involving the entire middle and posterior deltoid origins.^1,2

More recent analysis using 3D CT reconstruction of fractures has identified four distinct clusters of post reverse shoulder arthroplasty (RSA) ASFs corresponding to Levy types I, IIA, IIB, and III (Figure 7-3). This analysis further helped to identify the fracture patterns in addition to the clustering of fracture locations. Type I fractures involve the lateral acromion and demonstrate variable fracture patterning but are often in line with the acromioclavicular joint. Type IIA fractures are typically oblique and cluster around the transition between the acromion and scapular spine. Type IIB fractures are typically transverse and cluster in line with the level of the glenoid baseplate. Lastly, type III fractures are typically oblique occurring along the base of the scapular spine sometimes with extension into the scapular body.

Location of fracture has been shown to significantly influence the outcome of nonsurgical treatment. Boltuch et al observed a dichotomy among fractures based on location relative to the glenoid face in which medial fractures (Levy types IIB, IIC, and III) displayed inferior outcomes with nonsurgical management compared with matched controls who did not sustain an ASF, while lateral fractures (Levy types I and IIA) exhibited minimal impact on outcomes (Figure 7-4).² In discussion of these findings, the authors recommended that operative intervention be considered in patients with fractures medial to the glenoid face (Levy types IIB, IIC, and III).² Our current recommendation is to manage fractures medial to the glenoid face with surgical intervention, based upon these findings. Surgical management of lateral fractures that are painful and may limit motion remains justified.