01 September 2007
Coordination of the upper-limb segments in physiological tremor with various external loadsMasato Takanokura, Hitoshi Makabe, Kenichi Kaneko, Kazuyuki Mito, Kazuyoshi Sakamoto
Med Sci Monit 2007; 13(9): CR379-385 :: ID: 498391
Background: This study investigates coordination of the upper-limb segments with various external loads by frequency-domain analysis of physiological tremor during the maintenance of limb posture. Physiological tremor is an involuntary oscillation in every segment of a healthy human.
Material/Methods: A subject raised his right upper limb forward while extending his hand and fingers. Physiological tremor was measured by acceleration sensors attached to four segments: the index finger, hand, forearm, and upper arm. A balloon filled with helium gas was attached to the forearm as a minus-load condition. A weight band was attached as a plus-load condition. The measured signals were evaluated by frequency-domain analysis: power spectrum and coherence spectrum.
Results: The amplitude of upper-limb tremor measured from the four segments decreased with the minus-load and increased with the plus-load. However, the degree of the variation depended on the segment. The amplitude of upper-limb tremor measured from the forearm and the hand decreased remarkably with the minus-load, while the amplitude from the upper arm increased with the plus-load. Although adjacent segments were well coordinated, coordination between the segments varied depending on the external load. The minus-load at the forearm led to a lack of coordination between the upper arm and the forearm. To compensate for this, the movements of the forearm and the hand became coordinated.
Conclusions: The experimental protocol of this study allowed implementing a method to estimate the physiological modification of the neuromuscular system under a hypo-gravitational environment.
Keywords: Upper Extremity - physiology, Weight-Bearing - physiology
01 June 2023 : EditorialEditorial: Infectious Disease Surveillance Using Artificial Intelligence (AI) and its Role in Epidemic and Pandemic Preparedness
Med Sci Monit 2023; 29:e941209
08 Jun 2023 : Clinical ResearchRisk Factors for New Vertebral Compression Fracture After Percutaneous Vertebral Augmentation: A Retrospect...
Med Sci Monit In Press; DOI: 10.12659/MSM.940134
08 Jun 2023 : Clinical ResearchA Nomogram for Identifying HR+/Her2- Breast Cancer Patients with Positive Sentinel Lymph Nodes and Omitted ...
Med Sci Monit In Press; DOI: 10.12659/MSM.940124
08 Jun 2023 : Clinical ResearchBurden of COVID-19 on Mental Health of Resident Doctors in Poland
Med Sci Monit In Press; DOI: 10.12659/MSM.940208
08 Jun 2023 : Clinical ResearchRisk Prediction for Rapidly Progressive Interstitial Lung Disease in Anti-MDA5-Positive Dermatomyositis: Th...
Med Sci Monit In Press; DOI: 10.12659/MSM.940251
Most Viewed Current Articles
13 Nov 2021 : Clinical ResearchAcceptance of COVID-19 Vaccination and Its Associated Factors Among Cancer Patients Attending the Oncology ...
Med Sci Monit 2021; 27:e932788
30 Dec 2021 : Clinical ResearchRetrospective Study of Outcomes and Hospitalization Rates of Patients in Italy with a Confirmed Diagnosis o...
Med Sci Monit 2021; 27:e935379
08 Mar 2022 : Review articleA Review of the Potential Roles of Antioxidant and Anti-Inflammatory Pharmacological Approaches for the Man...
Med Sci Monit 2022; 28:e936292
01 Jan 2022 : EditorialEditorial: Current Status of Oral Antiviral Drug Treatments for SARS-CoV-2 Infection in Non-Hospitalized Pa...
Med Sci Monit 2022; 28:e935952