Kanai A1, Nojima O2, Goto H3, Uehara T4
1Toyohashi Sozo University, Toyohashi-City, Japan, 2Toyohashi Sozo University, Toyohashi, Japan, 3Tokyo Kasei University, Sayama-City, Japan, 4Toyohashi Orthopaedic Esaki Hospital, Toyohashi-City, Japan
Background: Restriction of the range of motion (ROM) of the hip joint is known to occur in elderly people. Yet, the joint reaction force and the change in the muscle activity of the lower limb due to the restriction of the hip joint ROM have not been sufficiently studied.
Purpose: We constructed a model tailored to each subject using the musculoskeletal computer system, and examined the influence of the restriction of the ROM of the hip joint.
Methods: The subjects were seven healthy adolescents of mean age 20.4 ± 0.5 years old. To simulate restriction of right hip joint ROM, the subjects were wearing the brace restricting ROM of the hip joint. The subjects carried out 3 times walking down a 10 m path with and without the brace. Measurements were taken using a three-dimensional motion analysis system (VICON MX: VICON, OR 6-7; AMTI, Nexus 2.3: VICON) regulated so that cadence and stride were the same. The joint angle during walking, joint moment due to external force, walking speed, and stride were calculated using analysis software VICON Polygon 3.5.1 (VICON), and the joint reaction force and muscle force were calculated using a musculoskeletal computer system (Any Body Modeling System 6.0.6, Anybody Technology Co.). Average maximum values in stance phase were calculated from three trials per subject, and values with and without restriction were compared by t-test. This study was approved by the Research Ethics Committee of Toyohashi SOZO University.
Results: The right hip joint flexion angle (p 0.05) and the ankle joint planter flexion (p 0.01) with brace were smaller than without brace. The right hip joint flexion moment with brace was smaller than without brace (p 0.01), but hip joint extension moment with brace was larger than without brace (p 0.05).The muscle force of the right hip joint extensors with brace were smaller than without brace (p 0.05), but the muscle force of the knee joint extensors and ankle joint planter flexors with brace were larger than without brace (p 0.05).The reaction force of right hip joint with brace were smaller than without brace (p 0.05), but the reaction force of left hip joint were larger than without brace (p 0.05).The reaction force of right ankle joint with brace were larger than without brace (p 0.05).
Conclusion(s): It was confirmed that the hip joint muscle force value was low due to the restriction of the ROM of the hip joint. In addition, as the hip joint extension moment due to external force and the joint reaction force increased, the increase in the flexion moment on the opposite joint was confirmed.
Implications: These results provide new insight into our understanding into the mechanism of improvement of walking function of the elderly.
Keywords: Musculoskeletal computer system, hip joint, walk
Funding acknowledgements: We gratefully acknowledge the work of past and present members of our laboratory.
Purpose: We constructed a model tailored to each subject using the musculoskeletal computer system, and examined the influence of the restriction of the ROM of the hip joint.
Methods: The subjects were seven healthy adolescents of mean age 20.4 ± 0.5 years old. To simulate restriction of right hip joint ROM, the subjects were wearing the brace restricting ROM of the hip joint. The subjects carried out 3 times walking down a 10 m path with and without the brace. Measurements were taken using a three-dimensional motion analysis system (VICON MX: VICON, OR 6-7; AMTI, Nexus 2.3: VICON) regulated so that cadence and stride were the same. The joint angle during walking, joint moment due to external force, walking speed, and stride were calculated using analysis software VICON Polygon 3.5.1 (VICON), and the joint reaction force and muscle force were calculated using a musculoskeletal computer system (Any Body Modeling System 6.0.6, Anybody Technology Co.). Average maximum values in stance phase were calculated from three trials per subject, and values with and without restriction were compared by t-test. This study was approved by the Research Ethics Committee of Toyohashi SOZO University.
Results: The right hip joint flexion angle (p 0.05) and the ankle joint planter flexion (p 0.01) with brace were smaller than without brace. The right hip joint flexion moment with brace was smaller than without brace (p 0.01), but hip joint extension moment with brace was larger than without brace (p 0.05).The muscle force of the right hip joint extensors with brace were smaller than without brace (p 0.05), but the muscle force of the knee joint extensors and ankle joint planter flexors with brace were larger than without brace (p 0.05).The reaction force of right hip joint with brace were smaller than without brace (p 0.05), but the reaction force of left hip joint were larger than without brace (p 0.05).The reaction force of right ankle joint with brace were larger than without brace (p 0.05).
Conclusion(s): It was confirmed that the hip joint muscle force value was low due to the restriction of the ROM of the hip joint. In addition, as the hip joint extension moment due to external force and the joint reaction force increased, the increase in the flexion moment on the opposite joint was confirmed.
Implications: These results provide new insight into our understanding into the mechanism of improvement of walking function of the elderly.
Keywords: Musculoskeletal computer system, hip joint, walk
Funding acknowledgements: We gratefully acknowledge the work of past and present members of our laboratory.
Topic: Human movement analysis; Musculoskeletal: lower limb
Ethics approval required: Yes
Institution: Toyohashi SOZO University
Ethics committee: Research Ethics Committee of Toyohashi SOZO University
Ethics number: H2016003
All authors, affiliations and abstracts have been published as submitted.
