The Journal of Bone and Joint Surgery (American). 2007;89:934-939.
doi:10.2106/JBJS.F.01075
© 2007 The Journal of Bone and Joint Surgery, Inc.
Impact of Fatty Infiltration of the Teres Minor Muscle on the Outcome of Reverse Total Shoulder Arthroplasty
Ryan W. Simovitch, MD1,
Naeder Helmy, MD2,
Matthias A. Zumstein, MD2 and
Christian Gerber, MD, FRCSEd2
1 Palm Beach Orthopaedic Institute, 3401 PGA Boulevard, Suite 500, Palm Beach
Gardens, FL 33401
2 University of Zurich, Balgrist, Forchstrasse 340, 8008 Zurich, Switzerland.
E-mail address for C. Gerber:
christian.gerber{at}balgrist.ch
Investigation performed at the Department of Orthopaedics, University
of Zurich, Balgrist, Zurich, Switzerland
Disclosure: In support of their research for or preparation of this
work, one or more of the authors received, in any one year, outside funding or
grants in excess of $10,000 from ResOrtho Foundation, Zurich, Switzerland.
Neither they nor a member of their immediate families received payments or
other benefits or a commitment or agreement to provide such benefits from a
commercial entity. No commercial entity paid or directed, or agreed to pay or
direct, any benefits to any research fund, foundation, division, center,
clinical practice, or other charitable or nonprofit organization with which
the authors, or a member of their immediate families, are affiliated or
associated.
Background: Reports have demonstrated that reverse shoulder
arthroplasty restores overhead elevation but fails to restore active external
rotation. The teres minor muscle-tendon unit contributes to active external
rotation, and its deficiency may impair the clinical outcome. It was therefore
the purpose of this study to evaluate the influence of fatty infiltration of
the teres minor muscle on the clinical outcome after reverse total shoulder
replacement.
Methods: Forty-two shoulders in forty-two patients (average age,
seventy-one years) with painful cuff tear arthropathy or an irreparable
rotator cuff deficiency with pseudoparesis were treated with a reverse
Delta-III shoulder arthroplasty and followed clinically for a minimum of
twenty-four months. Preoperatively, fatty infiltration of the teres minor was
assessed, according to the grading system of Goutallier et al., with use of
magnetic resonance imaging. The effect of teres minor fatty infiltration on
the subjective and objective outcomes of the reverse shoulder arthroplasty was
evaluated.
Results: The thirty shoulders with stage-0, 1, or 2 fatty
infiltration of the teres minor muscle (group 1) had a significantly better
ultimate Constant score, a significantly better subjective shoulder value, and
significantly greater preoperative-to-postoperative improvement than the
twelve shoulders with stage-3 or 4 fatty infiltration (group 2). In group 1
the relative Constant score increased by an average of 41% and the subjective
shoulder value increased by an average of 44%, whereas in group 2 the
respective increases were 32% (p = 0.033) and 25% (p = 0.018). Group 1 had an
average increase of 6.2 points in the score for extremity positioning, whereas
group 2 gained only 5.3 points (p = 0.033). Group 1 had a net gain of 9°
of external rotation with the arm at the side compared with an average net
loss of 7° in group 2 (p < 0.001).
Conclusions: Stage-3 or 4 fatty infiltration of the teres minor
compromises the clinical outcome of reverse shoulder arthroplasty for the
treatment of irreparable rotator cuff tears.
Level of Evidence: Prognostic Level II. See Instructions
to Authors for a complete description of levels of evidence.

CiteULike Connotea Del.icio.us Technorati What's this?
This article has been cited by other articles:

|
 |

|
 |
 
D. Cuff, D. Pupello, N. Virani, J. Levy, and M. Frankle
Reverse Shoulder Arthroplasty for the Treatment of Rotator Cuff Deficiency
J. Bone Joint Surg. Am.,
June 1, 2008;
90(6):
1244 - 1251.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
M. L. Ramsey, C. L. Getz, and B. O. Parsons
What's New in Shoulder and Elbow Surgery
J. Bone Joint Surg. Am.,
March 1, 2008;
90(3):
677 - 687.
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. Gerber, S. D. Pennington, E. J. Lingenfelter, and A. Sukthankar
Reverse Delta-III Total Shoulder Replacement Combined with Latissimus Dorsi Transfer. A Preliminary Report
J. Bone Joint Surg. Am.,
May 1, 2007;
89(5):
940 - 947.
[Abstract]
[Full Text]
[PDF]
|
 |
|
|