Decreased passive muscle stiffness of vastus medialis is associated with poorer quadriceps strength and knee function after anterior cruciate ligament reconstruction. (February 2021)

• Record Type: Journal Article
• Authors: He, Xin; Huang, Wan Yun; Leong, Hio Teng; Qiu, Ji Hong; Ma, Chun Cheong; Fu, Sai-Chuen; Ong, Michael Tim-Yun; Yung, Patrick Shu-Hang
• Is Part Of: Clinical biomechanics. Volume 82(2021)
• Publication Date: 2021-02
• Subjects: Anterior cruciate ligament -- Muscle stiffness -- Shear wave elastography -- Knee function; Biomechanics -- Periodicals; Osteopathic medicine -- Periodicals; Biomechanics -- Periodicals; Osteopathic Medicine -- Periodicals; 612.76
• DOI: 10.1016/j.clinbiomech.2021.105289
• Languages: English
• ISSNs: 0268-0033

Abstract

Abstract: Background: Muscle deficits of the quadriceps and hamstrings are common after anterior cruciate ligament reconstruction, and increase the risk of knee reinjury. Muscle stiffness is an important factor for dynamic joint stability. However, the changes in quadriceps and hamstring muscle stiffness and its influence after anterior cruciate ligament reconstruction remain unclear. Method: Twenty-five male subjects with anterior cruciate ligament reconstruction and twenty-one matched healthy subjects participated in this study. The passive muscle stiffness of the quadriceps and hamstrings was assessed by shear modulus using ultrasound shear wave elastography. The isokinetic muscle strengths of the quadriceps and hamstrings were tested. Knee function was evaluated by the International Knee Documentation Committee and Lysholm score. Muscle stiffness was compared between limbs via non-parametric tests. Correlation analysis was used to detect the relationship between muscle stiffness, isokinetic muscle strength and knee functional scores. Findings: The involved limb exhibited significantly decreased shear modulus in the vastus medialis compared to the dominant limbs(z = −3.585; P = 0.001;ES = 1.13) and non-dominant limbs(z = −3.551; P = 0.002;ES = 1.24) of healthy controls. The shear modulus of ST was also significantly lower in the involved limb when compared with the contralateral limbs(z = −3.996; P < 0.001;ES = 1.33), dominant limbs(z = −4.477;P < 0.001;ES = 1.65) and non-dominant limbs(z = −4.234; P = 0.001;ES = 1.43) of healthy controls. The shear modulus of the vastus medialis was associated with quadriceps peak torque at 60°/s( r = 0.470; p < 0.001) and knee functional score( r = 0.459; p = 0.021). Interpretation: The passive muscle stiffness of the vastus medialis decreased after anterior cruciate ligament reconstruction, which is associated with poorer quadriceps strength and knee function. The effect of modulation of muscle stiffness on improving knee function warrants future investigation. Highlights: Passive muscle stiffness of vastus medialis was decreased after anterior cruciate ligament reconstruction. Decreased stiffness of vastus medialis was associated with poorer quadriceps strength and knee function. Passive muscle stiffness of semitendinosus was decreased after harvesting hamstring tendon graft. Stiffness of semitendinosus was not associated with hamstring strength or knee function.