These authors sought to determine mid-to-long term (minimum 6 year) outcomes and reoperation rates for 35 patients receiving augmented (n=16) or non-augmented (n=19) aTSA for treatment of glenohumeral osteoarthritis with Walch B3 glenoid deformity - that is a mono concave glenoid with increased retroversion.
Preoperative glenoid retroversion was 24˚+/-8.6˚ in the standard cohort and 29˚+/- 5.8˚ in those who received augmented glenoid components. At the time of glenoid preparation, there was anterior perforation of the central peg hole in 5 patients in the standard component cohort and 9 patients in the augmented component cohort.
At final follow-up there were no statistically significant differences between those with augmented and standard glenoid components for mean ASES score (93.3 vs 85.7), ASES pain score (47.2 vs 41.6), SANE score (87.8 vs 86.0), and percent patient satisfaction (95.6% vs 96.8%), forward elevation (148˚ vs 149˚), or external rotation (36˚ vs 39˚). No patient in either group had undergone revision surgery of the operative shoulder over the study period and all patients would want to undergo the same surgery again.
While the authors reported that shoulders receiving standard components had the version "partially corrected with asymmetric reaming", they did not report the postoperative version or the change in version for the augmented or standard glenoid components.
Comment: These authors achieved excellent 6 year outcomes in managing B3 glenoids without a significant difference between those treated with augmented and standard glenoid components. They concluded that in their experience an anatomic shoulder arthroplasty was appropriate management for the B3 glenoid.
As pointed out in Subluxation in the Arthritic Shoulder, humeral head is centered (not posteriorly decentered) in the B3 glenoid, just as it is in the A2 glenoid. The difference between the A2 and the B3 glenoid types is based on the latter being retroverted by an arbitrarily defined 15 degrees (see this link).
A recent publication, Anatomic Total Shoulder Arthroplasty with All-Polyethylene Glenoid Component for Primary Osteoarthritis with Glenoid Deficiencies reported clinical and radiographic outcomes treating B3 glenoids with TSA with a standard all polyethylene glenoid component without attempting to normalize glenoid version. In that series glenoid version averaged 26 degrees preoperatively and 23 degrees postoperatively. The humeral heads were well centered postoperatively. Simple shoulder test scores improved from 3/12 to 10/12.
The data for all glenoid types are shown below.
In a related article, Does Postoperative Glenoid Retroversion Affect the 2-Year Clinical and Radiographic Outcomes for Total Shoulder Arthroplasty? standard glenoid components inserted in more than 15 degrees of retroversion did not have results inferior to those inserted in less than 15 degrees of retroversion. The humeral heads were well centered in both groups.
These articles suggest that postoperative centering of the humeral head on the glenoid may be more important to the outcome than the postoperative glenoid version.
A glenoid bone-preserving approach to total shoulder arthroplasty using a standard glenoid component is shown in this link..
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Here are some videos that are of shoulder interest
