Saturday, March 22, 2014

The magical role of eccentric prosthetic humeral heads in creating a stable shoulder arthroplasty

An eccentric humeral head prosthesis is one in which the articular surface is offset from the fixation peg
as shown to the right below.



The original thought with these eccentric heads was to use them to achieve coverage of the humeral neck and, thereby help restore the preoperative anatomy.

We have discovered, however, that creative use of the eccentric humeral heads can enable us to stabilize the humeral head on the glenoid in the face of severe glenoid deformity: the bad arthritic triad (BAT) as shown in the ream and run case below. Note in the preoperative axillary view the severe B2 glenoid with posterior humeral head subluxation.
 Note in the postoperative axillary view below the centering of the humeral head with the anteriorly eccentric humeral head prosthesis.
To see how this shoulder is functioning two years after surgery, open the youtube on this post.


The eccentric humeral head can also be used in excessively anteverted glenoids. In this total shoulder case we resolved a tendency for anterior instability by using a posteriorly eccentric humeral head.



===

Check out the new Shoulder Arthritis Book - click here.

Click here to see the new Rotator Cuff Book

Consultation for those who live a distance away from Seattle.

Use the "Search" box to the right to find other topics of interest to you.