Trunk muscle forces and spinal loads in persons with unilateral transfemoral amputation during sit-to-stand and stand-to-sit activities

Abstract

Background: Alterations and asymmetries in trunk motions during activities of daily living, involving lower extremities, are suggested to cause higher spinal loads in persons with unilateral lower limb amputation. Given the repetitive nature of most activities of daily living, knowledge of the amount of increase in spinal loads is important for designing interventions aimed at prevention of secondary low back pain due to potential fatigue failure of spinal tissues. The objective of this study was to determine differences in trunk muscle forces and spinal loads between persons with and without lower limb amputation when performing sit-to-stand and stand-to-sit tasks. Methods: Kinematics of the pelvis and thorax, obtained from ten males with unilateral transfemoral lower limb amputation and 10 male uninjured controls when performing sit-to-stand and stand-to-sit activities, were used within a non-linear finite element model of the spine to estimate trunk muscle forces and resultant spinal loads. Findings: The peak compression force, medio-lateral (only during stand-to-sit), and anteroposterior shear forces were respectively 348N, 269N, and 217N larger in person with vs. without amputation. Persons with amputation also experienced on average 171N and 53N larger mean compression force and medio-lateral shear force, respectively.

Compensatory Gait Strategies in Persons with Transfemoral Amputations Walking with a Locked Prosthetic Knee Joint Compared with an Unlocked Knee Joint: A Crossover Trial

“…This active lordosis movement could induce additional stress on the lumbar spine, which could result in low back pain over time. 10,11,[19][20][21] At the same time, during gait cycles, our results show that the maximum time of the pelvic and spinal rotation at the amputated side is increased with the LPKJ, showing the same timing as the pelvic tilt.…”

“…Because the ground reaction force can no longer influence the pelvis and spine through the swinging leg, we argue that the lumbar spinal extensor muscles are responsible for the extension of the lumbar spine. This active lordosis movement could induce additional stress on the lumbar spine, which could result in low back pain over time 10,11,19–21 . At the same time, during gait cycles, our results show that the maximum time of the pelvic and spinal rotation at the amputated side is increased with the LPKJ, showing the same timing as the pelvic tilt.…”

Exercise Therapy in Nonspecific Low Back Pain among Individuals with Lower-Limb Amputation: A Systematic Review

“…The trunk muscle forces and spinal loads during sit-to-stand and stand-to-sit activities were analysed by Shojaei et al [ 31 ]. In the experimental group, there were 10 males with unilateral transfemoral amputation (TFA), and the control group was composed of 10 non-amputees.…”