Patellofemoral joint load and knee abduction/adduction moment are sensitive to variations in femoral version and individual muscle forces

Abstract

Torsional profiles of the lower limbs, such as femoral anteversion, can dictate gait and mobility, joint biomechanics and pain, and functional impairment. It currently remains unclear how the interactions between femoral anteversion, kinematics, and muscle activity patterns contribute to joint biomechanics and thus conditions such as knee pain. This study presents a computational modeling approach to investigating the interactions between femoral anteversion, muscle forces, and knee joint loads.We employed an optimal control approach to produce actuator and muscle-driven simulations of the stance phase of gait for femoral anteversion angles ranging from −8°(retroversion) to 52°(anteversion) with a typically developing baseline of 12°of anteversion and implemented a Monte Carlo analysis for variations in lower limb muscle forces. While total patellofemoral joint load decreased with increasing femoral anteversion, patellofemoral joint load alignment worsened, and knee abduction/adduction magnitude increased with both positive and negative changes in femoral anteversion (p < 0.001). The rectus femoris muscle was found to greatly influence patellofemoral joint loads across all femoral anteversion alignments (R > 0.8, p < 0.001), and the medial gastrocnemius was found to greatly influence knee abduction/adduction moments for the extreme version cases (R > 0.74, p < 0.001). Along with the vastus lateralis, which decreased with increasing femoral anteversion (R = 0.89, p < 0.001), these muscles are prime candidates for future experimental and clinical efforts to address joint pain in individuals with extreme femoral version. These findings, along with future modeling efforts, could help clinicians better design treatment strategies for knee joint pain in populations with extreme femoral anteversion or retroversion.

How do the femoral anteversion angle and neck-shaft angle influence muscle forces and joint loading during walking?

“…This is in agreement with the observed increases in rectus femoris forces in our models with large AVA. Combining our ndings with the results from Wheatley et al 57 further supports the hypothesis that higher rectus muscle forces counterbalance the increased hip extensor muscle moments in models with large AVA (summarized in detail above), leading to increased knee and patellofemoral joint contact forces.…”

“…In another paper they showed that the patient-speci c gait pattern reduces hip loading in children with increased AVA 20 . Heller et al 21 showed that increasing the AVA increases hip joint contact forces when tracking the same kinematics, which was con rmed by recent simulation studies [22][23][24] . Increased hip and patellofemoral loading was found in children with increased AVA and normal foot progression angle 25 , whereas decreased hip and knee loads were observed in children with increased AVA and internal foot progression angle compared to healthy control participants 26 .…”

“…muscle-driven simulations, which also altered joint kinematics and kinetics and therefore makes a direct comparison with our ndings di cult. Nevertheless, the rectus femoris was found to greatly in uence patellofemoral loads with altered AVA 57 . This is in agreement with the observed increases in rectus femoris forces in our models with large AVA.…”

Influence of femoral anteversion angle and neck-shaft angle on muscle forces and joint loading during walking

“…A recent simulation study [28] investigated the impact of femoral AVA on patellofemoral joint loads. The authors found increased patellofemoral loads when AVA was increased from 22° to 42°, whereas a decrease in joint load was observed for the model with an AVA of 52°.…”

“…In another paper they showed that the patient-speci c gait pattern reduces hip loading in children with increased AVA [24]. Heller et al [25] showed that increasing the AVA increases hip joint contact forces when tracking the same, subject-speci c motion capture data of four patients with a total hip arthroplasty, which was con rmed by recent simulation studies [26][27][28]. Increased hip and patellofemoral loading was found in children with increased AVA and normal foot progression angle [29], whereas decreased hip and knee loads were observed in children with increased AVA and internal foot progression angle compared to healthy control participants [30].…”