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Updated: Sep 4, 2025

Reverse Total Shoulder Arthroplasty
Published on: July 5, 2011
The Rotator Cable Does Not Stress Shield the Crescent Area During Shoulder Abduction
Christopher C Schmidt1,2,3, Christopher S Spicer2,3, Dimitrios V Papadopoulos1,2
1Department of Orthopaedic Surgery, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania.
Background:
It is accepted by the orthopaedic community that the rotator cable (RCa) acts as a suspension bridge that stress shields the crescent area (CA). The goal of this study was to determine if the RCa does stress shield the CA during shoulder abduction.
Methods:
The principal strain magnitude and direction in the RCa and CA and shoulder abduction force were measured in 20 cadaveric specimens. Ten specimens underwent a release of the anterior cable insertion followed by a posterior release. In the other 10, a release of the posterior cable insertion was followed by an anterior release. Testing was performed for the native, single-release, and full-release conditions. The thicknesses of the RCa and CA were measured.
Results:
Neither the principal strain magnitude nor the strain direction in either the RCa or the CA changed with single or full RCa release (p ≥ 0.493). There were no changes in abduction force after single or full RCa release (p ≥ 0.180). The RCa and CA thicknesses did not differ from one another at any location (p ≥ 0.195).
Conclusions:
The RCa does not act as a suspension bridge and does not stress shield the CA. The CA primarily transfers shoulder abduction force to the greater tuberosity.
Clinical Relevance:
The CA is important in force transmission during shoulder abduction, and efforts should be made to restore its continuity with a repair or reconstruction.
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