Bradley Bowser1, Sean O'Rourke2, Cathleen N Brown3, Lesley White4, Kathy J Simpson5. 1. Department of Health and Nutritional Sciences, South Dakota State University, Brookings, SD, USA. Electronic address: bradley.bowser@sdstate.edu. 2. Columbia University, New York, NY, USA. 3. Department of Kinesiology, University of Georgia, Athens, GA, USA. Electronic address: browncn@uga.edu. 4. Department of Kinesiology, University of Georgia, Athens, GA, USA. Electronic address: ljwhite@uga.edu. 5. Department of Kinesiology, University of Georgia, Athens, GA, USA. Electronic address: kjsimpsonuga@gmail.com.
Abstract
BACKGROUND: It is unclear how people with multiple sclerosis, who often have compromised strength and balance, compare to healthy controls during sit-to-stand movements. The purpose of this study was to compare sit-to-stand biomechanics among three groups: people with multiple sclerosis who exhibit leg weakness, people with multiple sclerosis who have comparable strength to controls, and healthy controls. METHODS: Twenty-one individuals with multiple sclerosis (n=10 exhibiting leg weakness: n=11 exhibiting comparable strength to controls), and 12 controls performed five sit-to-stand trials while kinematic data and ground reaction forces were captured. ANOVAs followed by Tukey's post-hoc tests (α=0.05) were used to determine group and limb differences for leg strength, movement time, and sagittal-plane joint kinematics and kinetics. FINDINGS: Persons with multiple sclerosis exhibiting leg weakness displayed decreased leg strength, greater trunk flexion, faster trunk flexion velocity and decreased knee extensor power compared to the other two groups (p<0.05; d≥0.87), and slower rise times compared to controls(p<0.03; d≥1.17). No differences were found between controls and the multiple sclerosis-comparable strength group. Across all 3 groups, leg strength was moderately correlated with trunk kinematics and knee extensor velocities, moments and powers of the sit-to-stand (p≤0.05). INTERPRETATION: Participants with multiple sclerosis exhibiting leg weakness took longer to stand and appeared to use a trunk-flexion movement strategy when performing the sit-to-stand. The majority of group differences appear to be a result of leg extension weakness. Treatment that includes leg strengthening may be necessary to improve sit-to-stand performance for people with multiple sclerosis.
BACKGROUND: It is unclear how people with multiple sclerosis, who often have compromised strength and balance, compare to healthy controls during sit-to-stand movements. The purpose of this study was to compare sit-to-stand biomechanics among three groups: people with multiple sclerosis who exhibit leg weakness, people with multiple sclerosis who have comparable strength to controls, and healthy controls. METHODS: Twenty-one individuals with multiple sclerosis (n=10 exhibiting leg weakness: n=11 exhibiting comparable strength to controls), and 12 controls performed five sit-to-stand trials while kinematic data and ground reaction forces were captured. ANOVAs followed by Tukey's post-hoc tests (α=0.05) were used to determine group and limb differences for leg strength, movement time, and sagittal-plane joint kinematics and kinetics. FINDINGS:Persons with multiple sclerosis exhibiting leg weakness displayed decreased leg strength, greater trunk flexion, faster trunk flexion velocity and decreased knee extensor power compared to the other two groups (p<0.05; d≥0.87), and slower rise times compared to controls(p<0.03; d≥1.17). No differences were found between controls and the multiple sclerosis-comparable strength group. Across all 3 groups, leg strength was moderately correlated with trunk kinematics and knee extensor velocities, moments and powers of the sit-to-stand (p≤0.05). INTERPRETATION:Participants with multiple sclerosis exhibiting leg weakness took longer to stand and appeared to use a trunk-flexion movement strategy when performing the sit-to-stand. The majority of group differences appear to be a result of leg extension weakness. Treatment that includes leg strengthening may be necessary to improve sit-to-stand performance for people with multiple sclerosis.
Authors: Carmen Gutiérrez-Cruz; F Javier Rojas-Ruiz; Juan Carlos De la Cruz-Márquez; Marcos Gutiérrez-Dávila Journal: Int J Environ Res Public Health Date: 2020-09-02 Impact factor: 3.390