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Relationship Between Thoracic Spine Rotation Range, Trunk Contralateral Flexion Angle, and Maximum Elbow Valgus
1Department of Physical Therapy, Faculty of Health Science Technology, Bunkyo Gakuin University, Saitama, JPN.
Cureus
|April 7, 2025
Summary
The lumbar rock rotation test (LLR-t) may help identify pitchers with excessive trunk flexion and high elbow valgus torque. This test correlates with trunk motion and torque, aiding in injury prevention for baseball pitchers.
Area of Science:
- Biomechanics
- Sports Medicine
- Orthopedics
Background:
- Excessive trunk contralateral flexion is linked to increased elbow valgus torque in pitchers.
- The precise cause of this trunk motion remains unclear.
- Understanding this relationship is crucial for injury prevention.
Purpose of the Study:
- To investigate the relationship between the lumbar rock rotation test (LLR-t), trunk contralateral flexion during maximum external rotation (MER), and elbow valgus torque in baseball pitchers.
Main Methods:
- A descriptive laboratory study involving 21 male baseball pitchers.
- Measurements included LLR-t, trunk contralateral flexion angle at MER (using ImageJ), and maximum elbow valgus torque (using IMU).
Main Results:
- A significant negative correlation was found between the throwing-side LLR-t and both trunk contralateral flexion angle during MER (r=-0.51, p=0.02) and maximum elbow valgus torque (r=-0.45, p=0.04).
- Trunk contralateral flexion angle during MER positively correlated with maximum elbow valgus torque (r=0.47, p=0.03).
Conclusions:
- The LLR-t may serve as a valuable tool for assessing thoracic spine rotation range of motion.
- It can help identify athletes exhibiting increased trunk contralateral flexion and elevated elbow valgus torque during pitching.
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