Mechanical Determinants of Upper Limbs Oscillation During Gait

Summary

It is unclear why humans typically swing their arms during gait. To date, the debate on how to arm swing comes about (i.e. whether it is caused by accelerations of the shoulder girdle or muscular activity) is still going on. There needs to be consensus on whether the arm swing is actively controlled or merely passive and on why humans swing their arms during walking (i.e. what the purpose of arm swing is, if any). Suggested reasons include minimising energy consumption, optimising stability, and optimising neural control. Pathologies such as hemiplegia after stroke, Parkinson's disease, Cerebral Palsy, Spinal Cord Injury, and Multiple Sclerosis may directly affect arm swing during gait. Emerging evidence indicates that including arm movements in gait rehabilitation may be beneficial in restoring interlimb coordination and decreasing energy expenditure.

This project hypothesises that the arms swing, at least at low and intermediate walking speeds, reflects the body's Center of Mass (CoM) accelerations. Arm swing may thus depend mainly upon the system's intrinsic mechanical properties (e.g., gravity and inertia). In this perspective, the CoM is seen as moving relative to the upper limbs rather than the other way around. The contribution of major lower limb joints, in terms of power injected into the body motion, will be simultaneously explored.

The study aims to investigate the mechanism and functions of arm swinging during walking on a force treadmill. To simulate asymmetric walking, healthy subjects will be asked to walk with a toes-up orthosis to induce claudication and asymmetry in ankle power. In this way, it will be possible to highlight the correlation among arm swinging, ankle power, and the acceleration of the CoM in a 3D framework. In addition, subjects affected by unilateral motor impairments will be asked to walk on the force treadmill to test the experimental model and highlight significant differences in the kinematic parameters of the upper limbs.

The question of whether arm swing is actively controlled or merely passive and the relationship between arm swinging and the total mechanical energy of the CoM will be faced.

Asymmetric oscillations of the upper limb will be related to dynamic asymmetries of the COM motion, and of the motion of lower limbs. In addition, cause-effect relationships will be hypothesized. Finally, the dynamic correlates of upper limb oscillations will make the clinical observation an interpretable clinical sign applicable to rehabilitation medicine.

Results from the present study will also foster the identification of practical rehabilitation exercises on gait asymmetries in many human nervous diseases.

Conditions

• Multiple Sclerosis
• Poststroke/CVA Hemiparesis
• Parkinson Disease
• Cerebral Palsy
• Amputation

Interventions

OTHER

Healthy subjects

Participants' ground spontaneous speed overground will be tested by means of the 10-meter walking test. Participants will be tested for their foot dominance by means of the Waterloo footedness questionnaire-revised. Participants will walk on a treadmill mounted on force sensors. The test sequence will be the following: 1. Familiarization. Participants will walk on the treadmill with the belt running at increasing velocities up to their spontaneous walking velocity . Speed will be increased of 0.2 m s-1 every 30 s. A brief pause of around 1 minute will follow. 2. Walking. Participants will walk at 0.4 m s-1 and 1.2 m s-1 for at least 30 seconds. 3. Walking with a rigid ankle-foot orthosis. Participants will walk at 0.4 m s-1 and 1.2 m s-1 for at least 30 seconds with an ankle-foot orthosis on the dominant lower limb. Participants will repeat the last point (n°3) with the ankle-foot orthosis on the non-dominant lower limb. A 3-min pause will follow each section.

OTHER

Pathologic group

Participants will walk on a treadmill mounted on force sensors. They will walk freely, under tight supervision, but without hanging to any support. The test sequence will be the following: 4\. Familiarization. Participants will walk on the treadmill with the belt running at increasing velocities up to their spontaneous walking velocity . Speed will be increased of 0.1 m s-1 every 30 s. A brief pause of around 1 minute will follow. 5\. Walking. Participants will walk at 0.4 m s-1 for at least 30 seconds. Participants will be informed a few seconds before the changes in belts' velocities with a verbal warning.

Sponsors & Collaborators

• Istituto Auxologico Italiano

  lead OTHER

Principal Investigators

• Luigi Tesio, MD · Istituto Auxologico Italiano

Eligibility

Min Age

18 Years

Max Age

80 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2020-05-27

Primary Completion

2024-12-31

Completion

2024-12-31

Countries

• Italy

Study Locations