During level walking, lumbar spine is subjected to cyclic movements and intricate loading of the spinal discs and trunk musculature. This study aimed to estimate the spinal loads (T12âS1) and trunk muscles forces during a complete gait cycle. Six men, 24â33 years walk barefoot at self-selected speed (4â5 km/h). 3D kinematics and ground reaction forces were recorded using a motion capturing system and two force plates, implemented in an inverse dynamic musculoskeletal model to predict the spinal loads and trunk muscles forces. Additionally, the sensitivity of the intra-abdominal pressure and lumbar segment rotational stiffness was investigated. Peak spinal loads and trunk muscle forces were between the gait instances of heel strike and toe off. In L4âL5 segment, sensitivity analysis showed that average peak compressive, antero-posterior and medio-lateral shear forces were 130â179%, 2â15% and 1â6%, with max standard deviation (±STD) of 40%, 6% and 3% of the body weight. Average peak global muscles forces were 24â55% (longissimus thoracis), 11â23% (iliocostalis thoracis), 12â16% (external oblique), 17â25% (internal oblique) and 0â8% (rectus abdominus) of body weight whereas, the average peak local muscles forces were 11â19% (longissimus lumborum), 14â31% (iliocostalis lumborum) and 12â17% (multifidus). Maximum ± STD of the global and local muscles forces were 13% and 8% of the body weight. Large inter-individual differences were found in peak compressive and trunk muscles forces whereas the sensitivity analysis also showed a substantial variation.
Spinal loads and trunk muscles forces during level walking - A combined in vivo and in silico study on six subjects
Angelini, Lorenza;Di Puccio, Francesca;
2018-01-01
Abstract
During level walking, lumbar spine is subjected to cyclic movements and intricate loading of the spinal discs and trunk musculature. This study aimed to estimate the spinal loads (T12âS1) and trunk muscles forces during a complete gait cycle. Six men, 24â33 years walk barefoot at self-selected speed (4â5 km/h). 3D kinematics and ground reaction forces were recorded using a motion capturing system and two force plates, implemented in an inverse dynamic musculoskeletal model to predict the spinal loads and trunk muscles forces. Additionally, the sensitivity of the intra-abdominal pressure and lumbar segment rotational stiffness was investigated. Peak spinal loads and trunk muscle forces were between the gait instances of heel strike and toe off. In L4âL5 segment, sensitivity analysis showed that average peak compressive, antero-posterior and medio-lateral shear forces were 130â179%, 2â15% and 1â6%, with max standard deviation (±STD) of 40%, 6% and 3% of the body weight. Average peak global muscles forces were 24â55% (longissimus thoracis), 11â23% (iliocostalis thoracis), 12â16% (external oblique), 17â25% (internal oblique) and 0â8% (rectus abdominus) of body weight whereas, the average peak local muscles forces were 11â19% (longissimus lumborum), 14â31% (iliocostalis lumborum) and 12â17% (multifidus). Maximum ± STD of the global and local muscles forces were 13% and 8% of the body weight. Large inter-individual differences were found in peak compressive and trunk muscles forces whereas the sensitivity analysis also showed a substantial variation.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.