Three approaches to the B3 glenoid

As pointed out in Characterization of the Walch B3 glenoid in primary osteoarthritis, the type B3 arthritic pathoanatomy is characterized by a humeral head that is centered in a uniconcave retroverted glenoid (below right), but that lies posterior to the plane of the scapula (below center).

Using figures based on those from Early clinical and radiographic outcomes of anatomic total shoulder arthroplasty with a biconvex posterior augmented glenoid for patients with posterior glenoid erosion: minimum 2-year follow-up we can consider three different approaches to this type of arthritic pathoanatomy, each which has its proponents.

Corrective reaming to neutralize glenoid version and align the center of the humeral head with the plane of the scapula (see  How much does "corrective glenoid reaming" actually change version?) As shown below, this approach requires removal of a substantial amount of bone (red arrow) leaving less support for a glenoid component.

Using an augmented glenoid component to neutralize glenoid version and align the center of the humeral head with the plane of the scapula. (see Augmented glenoid components for B2 and B3 glenoids). As shown below, posteriorly directed loads are applied to thicker posterior polyethylene of the glenoid component. Theoretically, this might increase the risks of rocking horse loosening.

Conservative glenoid reaming - only as much reaming as is needed to achieve a glenoid concavity that conforms to the back of a standard glenoid component without an attempt to correct glenoid version or to align the humeral head with the scapular plane.  (See Arthritic glenoid retroversion: what to do about it.)

Comment: The optimal approach to the B3 glenoid is yet to be established and may depend on the characteristics of the individual patient and the experience of the surgeon. Yet as we go forward, it seems important to keep an eye on the evidence supporting the need for correcting glenoid version versus that favoring accepting the retroversion to which the soft tissues of the shoulder have become accustomed (see Glenoid version: acceptors and correctors).

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Here are some videos that are of shoulder interest
Shoulder arthritis - what you need to know (see this link).
How to x-ray the shoulder (see this link).
The ream and run procedure (see this link).
The total shoulder arthroplasty (see this link).
The cuff tear arthropathy arthroplasty (see this link).
The reverse total shoulder arthroplasty (see this link).
The smooth and move procedure for irreparable rotator cuff tears (see this link).
Shoulder rehabilitation exercises (see this link).