Analysis of contribution of muscle synergies on sit-to-stand motion using musculoskeletal model

Is the Hénon map able to predict the interaction dynamics between the knee and hip joints emerged during sit-to-stand movement?

“…The authors believe that STS transitions are equal to soft switching between different postural states, which is a sequence of emergent behaviors. The overwhelming majority of the published research in analyzing the STS movement area has addressed the muscle coordination dynamics and has modeled either the kinematic behavior of STS using simple multi-link models or the motion trajectories [9][10][11][12][13][14][15][16][17][18][19]. Nevertheless, the pattern of the kinematic interaction and synergetic coordination among the joints involved during STS has not been deeply scrutinized.…”

“…Most of the reported works focused on muscle coordination patterns have modeled joint trajectories which use simplified multi-link skeletal models or motion trajectories. In other words, one class of studies has emphasized identifying the muscle coordination dynamics, that underlie the sit-to-stand movement [9][10][11]. Some researchers have examined the relationships between biomechanics and muscle synergies [10].…”

“…Some researchers have examined the relationships between biomechanics and muscle synergies [10]. In addition, the relationships between the muscle synergy model and changes in joint angles during STS were described using a musculoskeletal model [9]. In another study, the temporal features of muscle synergies during STS were compared between healthy participants and post-stroke patients [11].…”

“…The emphasis of the aforementioned categorized studies was mainly on identifying muscle coordination dynamics and joint trajectories during STS were not addressed [9][10][11]. An overwhelming majority of the studies focused on modeling joint trajectories using simplified multi-link models without considering the muscle part [12][13][14][15][17][18][19].…”