This important paper points to the importance of posterior humeral subluxation and glenoid biconcavity in the conduct and outcome of shoulder arthroplasty.
In this series of 92 such patients, the glenoid bone was reamed asymmetrically to achieve a retroversion between 0 and 10 degrees. Seven shoulders had glenoid bone grafting because the desired glenoid anatomy could not be sufficiently corrected by reaming alone. Nine shoulders had posterior capsular tightening and 18 patients wore a brace in neutral rotation for a month after surgery. Apparently no patients had rotator interval plications or the use of eccentric humeral heads.
Twenty percent of the glenoid components were found to be loose and the occurrence of loosening was associated with the amount of posterior bone loss and humeral subluxation. This is a good example of rocking horse loosening.
Fifteen of these shoulders (16%) required revision for glenoid loosening and/or posterior humeral head dislocation, stiffness or pain. Posterior bone grafts and posterior capsular tightening were usually not successful in preventing revision.
Recognizing the difficulties of managing the not-uncommon situation of posterior humeral subluxation and glenoid biconcavity with a polyethylene socket, we have applied the ream and run with eccentric humeral head placement for active individuals with this situation. Although the authors suggest that a reverse total shoulder may be indicated in such situations, we are reluctant to use the reverse in patients wishing to be physically active.
----
If you have suggestions for topics you'd like us to address in this blog, please send an email to shoulderarthritis@uw.edu.
Use the "Search the Blog" box to the right to find other topics of interest to you.
You may be interested in some of our most visited web pages including:shoulder arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery.