Characterizing Material Properties of Rotator Cuff Tendons Relevant in Reverse Total Shoulder Arthroplasty Using...

Area of Science:

• Orthopedic biomechanics
• Biomaterials science
• Surgical reconstruction

Background:

• Rotator cuff tendon integrity impacts reverse total shoulder arthroplasty stability.
• Existing literature lacks detailed material properties for computational analysis of rotator cuff tendons.
• Accurate material definitions are needed for finite element analysis in reverse total shoulder arthroplasty.

Purpose of the Study:

• To characterize the material properties of rotator cuff tendons relevant to reverse total shoulder arthroplasty.
• To determine elastic modulus values for subscapularis, infraspinatus, and teres minor tendons.
• To compare material property measurements between different analysis methods.

Main Methods:

• Tensile testing of cadaveric rotator cuff tendon constructs.
• Utilized a materials testing system and two video-based strain measurement techniques.
• Derived stress-strain curves and elastic modulus values for quantitative analysis.

Main Results:

• Materials testing system yielded significantly lower elastic modulus values (49 ± 8 MPa) compared to video-based methods (186–217 MPa).
• Video-based measurement methods showed consistent results, with no significant differences between them.
• Elastic modulus values are underestimated when solely relying on materials testing system data.

Conclusions:

• Video-based strain measurement provides more accurate elastic modulus data for rotator cuff tendons.
• Rotator cuff tendon elastic modulus values are significantly higher than previously reported using only materials testing systems.
• The determined elastic modulus values are applicable for finite element analysis in reverse total shoulder arthroplasty.