Wyniki wyszukiwania - BazTech

Ograniczanie wyników

2 Acta of Bioengineering and Biomechanics

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: patellofemoral joint stress

Sortuj według:

Ogranicz wyniki do:

Effect of change in patellofemoral joint contact area by the decrease in vastus medialis muscle activation on joint stress

Tomoya Takabayashi, Mutsuaki Edama, Masayoshi Kubo, Takuma Inai

Acta of Bioengineering and Biomechanics

2023

Vol. 25, no. 2

41--47

Patellofemoral pain syndrome is a common orthopedic trauma among runners. It is unclear whether patellofemoral joint stress (PFJS) is the highest (or lowest) when the knee joint flexion angle and extension moment are in combination under the condition that vastus medialis (VM) activation decreases. This study aimed to investigate the effects of changes in the PFJ contact area by decreasing the activation of the VM muscle on PFJS. Methods: A PFJ sagittal model was used to quantify PFJ reaction force and PFJS. The PFJ model and mathematical modelling procedure were used to quantify PFJS based on previous studies. The simulation ranges were set to knee joint flexion angles of 10–45° and extension moments of 0–240 Nm. PFJS was calculated for the normal condition (NC) and decrease condition (DC) in VM activation. Results: When the knee joint angle and knee joint moment were at the maximum, the PFJS showed the maximum value under both conditions (NC; 14.9 N/cm2 , DC; 16.4 N/cm2 ). PFJS was found to be higher in DC than that in NC for all simulation ranges. Conclusion: Decreased VM activation may be involved in the mechanism of patellofemoral pain syndrome. In addition, the results of this study provide evidence that clinicians can enhance VM to relieve pain in patients with patellofemoral pain syndrome.

Influence of sex and knee joint rotation on patellofemoral joint stress

Takabayashi Tomoya, Edama Mutsuaki, Inai Takuma, Tokunaga Yuta, Kubo Masayoshi

Acta of Bioengineering and Biomechanics

2022

Vol. 24, no. 3

161--168

Females are two times as likely to experience patellofemoral pain syndrome (PFPS) than males, however, the reason for this difference between sexes remains unclear. Patellofemoral joint (PFJ) stress is believed to contribute to PFPS alterations through knee joint rotation alignment, but the influence of knee joint rotation conditions on PFJ stress is unclear. We aimed to investigate the influence of sex and knee joint rotation alignment on PFJ stress. Methods: Simulation ranges were set to knee joint flexion angles of 10–45° (common to both sexes) and extension moments of 0–240 Nm (males) and 0–220 Nm (females). The quadriceps force and effective lever arm length at the quadriceps muscle were determined as a function of the knee joint flexion angle and extension moment. The PFJ contact area, which is specific to sex, and knee joint rotation were calculated from cadaver data, and PFJ stress was estimated. Results: In all knee joint rotation conditions, PFJ stress was higher in females than in males. Additionally, PFJ stress in males and females was the largest under neutral conditions compared with other rotation conditions. Conclusion: The results of the present study may be useful for understanding the underlying mechanisms contributing to the differences in PFPS in males and females.