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Updated: Jun 5, 2026

Muscle Imbalances: Testing and Training Functional Eccentric Hamstring Strength in Athletic Populations
Published on: May 1, 2018
[Impact of muscle strength on knee joint stability in static loading]
Ping-yue Li1, Qing-shui Yin, Hua-yang Hang
1Department of Orthopedics, Guangzhou General Hospital of Guangzhou Command, China. lipingyue09@126.com
Objective:
To study the in vivo stability of normal and anterior cruciate ligament (ACL)-injured knee joint before and after epidural anesthesia under 134 N pre-loading and evaluate the influence of muscular tension on the knee stability.
Methods:
Eight volunteers with unilateral ACL rupture and normal contralateral knee were enrolled in this study. CT (3D) images and 2 orthogonal images of the knee were captured at 0°, 30°, 60°, and 90° under 134 N pre-loading. The orthogonal images were used to recreate the in vivo knee positions at each of the targeted flexion angles by 2D/3D registration to analyze the tibial translation data.
Results:
The anterior tibia translation of both the intact and ACL-injured knees after anesthesia was significantly different from that before anesthesia at all the angles (P<0.05). The anterior tibial translation of the intact knee after anesthesia increased by 1.7 mm at 0°, 2.7 mm at 30°, 2.6 mm at 60°, and 2.3 mm at 90°, as compare to the increase of ACL-injured knee by 4.2 mm, 2.6 mm, 1.2 mm, and 1.6 mm, respectively.
Conclusion:
The muscular tension has evident influence on the knee stability in static loading.
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