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Measuring 3D In-vivo Shoulder Kinematics using Biplanar Videoradiography
Published on: March 12, 2021
Identification of feigned maximal shoulder external rotation effort
Joaquim Chaler1, Zeevi Dvir, Urko Díaz
1Department of Physical Medicine and Rehabilitation, Mútua Egara, Terrassa, Spain. 27522jcv@comb.es
Clinical Rehabilitation
|March 3, 2007
Summary
The difference between eccentric to concentric strength ratios (DEC) effectively identifies feigned maximal shoulder external rotation effort. This method distinguished between real and faked maximal efforts in all participants tested.
Area of Science:
- Biomechanics and Sports Medicine
- Occupational Health and Rehabilitation
Background:
- Previous research suggests the difference between eccentric to concentric strength ratios (DEC) can identify feigned maximal effort.
- However, direct comparisons of maximal versus feigned maximal shoulder external rotation effort have not been previously studied.
- Given the high incidence of shoulder rotation disorders and their impact on occupational disability, this research is highly relevant.
Purpose of the Study:
- To evaluate the efficacy of the difference between eccentric to concentric strength ratios (DEC) at high and low velocities in detecting feigned maximal shoulder external rotation effort.
Main Methods:
- This study compared maximal and feigned maximal shoulder external rotation isokinetic efforts.
- Seventeen healthy male volunteers (aged 20-40) underwent concentric and eccentric isokinetic tests at 30°/s and 120°/s.
- The DEC was calculated by subtracting the 30°/s eccentric/concentric peak torque ratios from the 120°/s ratios under both maximal and feigned maximal conditions.
Main Results:
- A case-by-case analysis demonstrated that DEC scores from feigned efforts were significantly higher than those from maximal efforts in all subjects.
- A cut-off value of 0.81 was established, successfully differentiating between maximal and feigned maximal shoulder external rotation performances.
Conclusions:
- The difference between eccentric to concentric strength ratios (DEC) proves to be a highly effective method for identifying feigned maximal shoulder external rotation effort in healthy individuals.
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