2023, Vol. 27 ›› Issue (31): 4971-4976

Functional correlation between the elasticity of the quadriceps and its tendons and osteoarthritis of the knee based on shear wave elastography measurements

Huang Yuying1, 2, Guo Yi3, Han Xinzuo4, Min Hongwei1, 4, Li Xuemei3, Liu Kemin1, 4   

Abstract: BACKGROUND: It has been shown that muscle elasticity changes in patients with knee osteoarthritis, but most of the current studies have focused on the assessment of muscle tone and muscle strength. Changes in the elasticity of the quadriceps and its tendons in patients with knee osteoarthritis have rarely been reported.
OBJECTIVE: To investigate the characteristics of the elastic modulus of the quadriceps femoris and its tendons in patients with knee osteoarthritis and to analyze its relationship with knee pain and function, thereby providing some basis for the prevention and treatment of knee osteoarthritis.
METHODS: The elasticity of the quadriceps femoris and its tendons was measured by shear wave elastography in 30 patients with clinically confirmed knee osteoarthritis (knee osteoarthritis group) and 28 healthy individuals without knee pain (control group). The Western Ontario and McMaster University Osteoarthritis Index (WOMAC) was used for knee pain and function assessments in both groups. Changes in the modulus of elasticity of the quadriceps were compared between the two groups. The correlation between the elastic modulus of the quadriceps muscle and the WOMAC score was statistically analyzed.
RESULTS AND CONCLUSION: (1) The thickness of the rectus femoris, middle femoris, medial femoris, lateral femoris and quadriceps tendon was less in the knee osteoarthritis group than in the control group. The elastic modulus of the lateral femoris was significantly higher in the knee osteoarthritis group than in the control group (P < 0.05). (2) The elastic modulus of muscles that was characteristically different from the control group was selected for correlation analysis. The elastic modulus of the lateral femoris in the knee osteoarthritis group showed a low linear correlation with the WOMAC pain scale (r=0.367, P < 0.05). In the self-reported pain scale, the elastic modulus of the lateral femoris in patients with knee osteoarthritis was only moderately linearly positively correlated with pain level during going up/downstairs (r=0.584, P < 0.05). In the self-reported functional impairments scale, patients with knee osteoarthritis showed a moderate linear correlation between the elastic modulus of the lateral femoris and the function when going downstairs and getting up from a seat (r=0.411, P < 0.05; r=0.464, P < 0.05). (3) From the above, an increased stiffness of the lateral femoris may be a characteristic change in the quadriceps muscle of patients with knee osteoarthritis. This in turn reflects the pain and function of the knee joint during increased loading. Further research is needed to investigate the significance of the modulus of elasticity in assessing the condition and outcome of patients with knee osteoarthritis, so as to achieve the precise rehabilitation treatment.

Key words: knee osteoarthritis, shear wave elastography, quadriceps femoris, elastic modulus, WOMAC score