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Updated: Feb 5, 2026
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Biomechanical Testing of Murine Tendons
Published on: October 15, 2019
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Tendon Transfer Options for Trapezius Paralysis: A Biomechanical Study.
Jean-David Werthel1, Eric R Wagner, John W Sperling
1From the Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN.
The Journal of the American Academy of Orthopaedic Surgeons
|September 15, 2018
Summary
A modified Eden-Lange (EL) transfer effectively restored scapulothoracic upward rotation, mimicking normal trapezius function better than the traditional EL transfer for paralyzed trapezius muscles.
Area of Science:
- Biomechanics
- Orthopedic Surgery
- Rehabilitation Medicine
Background:
- Trapezius muscle paralysis impairs scapular stability and arm function.
- Tendon transfer surgery aims to restore shoulder function in cases of paralysis.
- Scapulothoracic (ST) upward rotation is crucial for effective arm elevation.
Purpose of the Study:
- To biomechanically evaluate two tendon transfer procedures for ST upward rotation.
- To compare the effectiveness of the Eden-Lange (EL) transfer and a modified triple transfer.
- To restore function in patients with paralyzed trapezius muscles.
Main Methods:
- Biomechanical analysis of six fresh frozen hemithoraces.
- Utilized a 3D electromagnetic tracking system to measure ST rotation.
- Compared normal trapezius, EL transfer, and modified EL transfer (triple transfer) function.
Main Results:
- The normal trapezius produced a mean ST upward rotation of 26.98°.
- The modified triple transfer resulted in a mean ST upward rotation of 22.23°.
- The traditional EL transfer caused initial downward rotation (-6.69°) and minimal displacement (1.13°).
Conclusions:
- The modified triple transfer more effectively mimicked the upward rotatory function of the normal trapezius.
- This modified procedure shows promise for improving shoulder function after trapezius paralysis.
- Tendon transfer biomechanics are critical for successful functional restoration.
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