These authors point out that patients having reverse total shoulder arthroplasty (rTSA) may have limited preoperative external rotation (ER) because of either stiffness or weakness.
They considered the outcomes of 608 patients having a primary rTSA using the Eactech Equinoxe prosthesis with a "medial glenoid lateral humerus". None of these patients had tendon transfers.
Patients with limited preoperative external rotation due to weakness or stiffness were compared to patients with normal preoperative range of motion.
The specific preoperative criteria for each cohort was defined as follows:
The specific preoperative criteria for each cohort was defined as follows:
(1) Normal cohort: passive ER 30 and a lag <10;
(2) Stiff cohort: passive ER 20 and a lag 10;
(3) Weak cohort: passive ER 30 and a lag 20.
They found that stiff patients had greater improvement in their clinical scores than patients with weak or normal preoperative ER.
Comment:
See related post (click on this link)
A recent article, "A method for documenting the change in center of rotation with reverse total shoulder arthroplasty and its application to a consecutive series of 68 shoulders having reconstruction with one of two different reverse prostheses" (see this link) helps understand the effect of a reverse total shoulder on external rotation and the importance of prosthesis design. The authors showed that a reverse medializes the center of rotation
and that the amount of medialization differs among prosthesis designs as shown below.
This is shown nicely in the figure below from Steve Lippitt. (A) is the normal shoulder, (B) shows the relaxation of the residual rotators including the posterior deltoid and remaining cuff) with a lot of medialization (which can weaken external rotation), while (C) shows tensioning of the posterior residual rotators by an implant with less medialization (which can restore external rotation).
===
To see a YouTube of our technique for a reverse total shoulder arthroplasty, click on this link.
===
How you can support research in shoulder surgery Click on this link.
We have a new set of shoulder youtubes about the shoulder, check them out at this link.
Be sure to visit "Ream and Run - the state of the art" regarding this radically conservative approach to shoulder arthritis at this link and this link
Use the "Search" box to the right to find other topics of interest to you.
See related post (click on this link)
A recent article, "A method for documenting the change in center of rotation with reverse total shoulder arthroplasty and its application to a consecutive series of 68 shoulders having reconstruction with one of two different reverse prostheses" (see this link) helps understand the effect of a reverse total shoulder on external rotation and the importance of prosthesis design. The authors showed that a reverse medializes the center of rotation
This is shown nicely in the figure below from Steve Lippitt. (A) is the normal shoulder, (B) shows the relaxation of the residual rotators including the posterior deltoid and remaining cuff) with a lot of medialization (which can weaken external rotation), while (C) shows tensioning of the posterior residual rotators by an implant with less medialization (which can restore external rotation).
Thus, "East-West" tensioning has the potential for improving active external rotation.
To see a YouTube of our technique for a reverse total shoulder arthroplasty, click on this link.
===
How you can support research in shoulder surgery Click on this link.
We have a new set of shoulder youtubes about the shoulder, check them out at this link.
Be sure to visit "Ream and Run - the state of the art" regarding this radically conservative approach to shoulder arthritis at this link and this link
Use the "Search" box to the right to find other topics of interest to you.
You may be interested in some of our most visited web pages arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery as well as the 'ream and run essentials'
