Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Alterations in Muscle Tone lll

Alterations in Muscle Tone lll

Rigidity and myotonia are distinct abnormalities of muscle tone that affect resistance and relaxation during movement. Although both involve altered muscle contraction, they arise from different neurological and muscular mechanisms.CharacteristicsRigidity is characterized by uniform resistance to passive movement across the entire range, independent of speed, affecting flexors and extensors equally. It may appear as lead-pipe rigidity (smooth, constant resistance) or cogwheel rigidity...

Motor Unit Stimulation

Motor Unit Stimulation

When the neuron of a motor unit fires an action potential, it triggers a series of events, leading to a twitch contraction in the muscle fibers. The process of excitation-contraction coupling is crucial in relaying the action potential to the muscle fibers.
The latent period of contraction marks the onset of excitation-contraction coupling, when the action potential propagates across the sarcolemma, preparing the muscle fibers for contraction. As the fibers enter the contraction phase, the...

Classification of Skeletal Muscle Relaxants

Classification of Skeletal Muscle Relaxants

Skeletal muscle relaxants are a group of drugs that can reduce muscle stiffness and induce temporary paralysis to relieve pain. These agents can act centrally to reduce muscle tone or spasms in painful conditions such as multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), or spinal injuries; they are called antispasmodics or spasmolytics.
Peripherally acting skeletal muscle relaxants interfere with the neurotransmission at the neuromuscular end plate to induce paralysis during...

Relaxation of Skeletal Muscles

Relaxation of Skeletal Muscles

The period of muscle contraction primarily influences the duration of stimulation at the neuromuscular junction (NMJ), the presence of free calcium ions in the sarcoplasm, and the availability of energy or ATP to support contractions.
When an action potential reaches the axon terminal, it depolarizes the membrane and opens voltage-gated sodium channels. Sodium ions enter the cell, further depolarizing the presynaptic membrane. This depolarization causes voltage-gated calcium channels to open.

Alterations in Muscle Tone ll

Alterations in Muscle Tone ll

Alterations in muscle tone are common manifestations of neurological disorders and reflect dysfunction within different nervous system regions. Spasticity, paratonia, and dystonia represent distinct forms of hypertonia, each with unique mechanisms, clinical features, and diagnostic importance.CharacteristicsSpasticity happens from upper motor neuron lesions and is characterized by velocity-dependent resistance to passive movement. Clinical features include:Exaggerated deep tendon reflexesClonus...

Muscle Stimulation Frequency

Muscle Stimulation Frequency

The contraction strength of muscles is regulated by motor neurons, which modulate the frequency of action potentials dispatched to the motor units based on the body's requirements. This process of varying the muscle stimulation frequency allows muscles to contract with a force that is precisely tailored to the needs of the moment, whether lifting a feather or a heavy box.
Wave summation
At low firing rates, motor neurons induce individual twitch contractions in muscle fibers. These twitches...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Circulating levels of dickkopf-1, osteoprotegerin and sclerostin are higher in old compared with young men and women and positively associated with whole-body bone mineral density in older adults.

Osteoporosis international : a journal established as result of cooperation between the European Foundation for Osteoporosis and the National Osteoporosis Foundation of the USA·2017

Same author

Diagnostic power of the non-ischaemic forearm exercise test in detecting glycogenosis type V.

European journal of neurology·2015

Same author

Validation of balance-quality assessment using a modified bathroom scale.

Physiological measurement·2015

Same author

Associations between muscle strength, spirometric pulmonary function and mobility in healthy older adults.

Age (Dordrecht, Netherlands)·2014

Same author

The French Pompe registry. Baseline characteristics of a cohort of 126 patients with adult Pompe disease.

Revue neurologique·2013

Same author

Innovative methods to assess upper limb strength and function in non-ambulant Duchenne patients.

Neuromuscular disorders : NMD·2012

Search research articles

Related Experiment Video

Updated: Jun 22, 2026

Myo-mechanical Analysis of Isolated Skeletal Muscle

Myo-mechanical Analysis of Isolated Skeletal Muscle

Published on: February 22, 2011

Quantitative myotonia assessment using force relaxation curve modelling.

¹Institut de Myologie, GH Pitié-Salpêtrière, 75651 Paris Cedex 13, France. jy.hogrel@institut-myologie.org

Physiological Measurement

|June 25, 2009

Summary

A new regression model accurately quantifies myotonia by analyzing force relaxation times. This method offers a robust and objective assessment for myotonic dystrophy type 1 (DM1) patients in clinical settings.

More Related Videos

Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI

Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI

Published on: April 18, 2011

Measuring Neuromuscular Junction Functionality

Measuring Neuromuscular Junction Functionality

Published on: August 6, 2017

Related Experiment Videos

Last Updated: Jun 22, 2026

Myo-mechanical Analysis of Isolated Skeletal Muscle

Myo-mechanical Analysis of Isolated Skeletal Muscle

Published on: February 22, 2011

Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI

Methods to Quantify Pharmacologically Induced Alterations in Motor Function in Human Incomplete SCI

Published on: April 18, 2011

Measuring Neuromuscular Junction Functionality

Measuring Neuromuscular Junction Functionality

Published on: August 6, 2017

Area of Science:

Biomedical Engineering
Clinical Neuroscience
Neuromuscular Disorders

Background:

Quantitative assessment of myotonia lacks robust methods.
Existing force relaxation time measurements have drawbacks like instability and noise.
Developing a reliable myotonia quantification is crucial for clinical settings.

Purpose of the Study:

To provide an automated regression model for fitting force relaxation curves.
To establish a robust index for quantitative myotonia assessment.
To address limitations of current myotonia measurement techniques.

Main Methods:

Force curves were fitted using an asymmetric sigmoidal function.
An inverse function was employed to calculate relaxation times automatically.
Variables were computed for 16 controls and 16 myotonic dystrophy type 1 (DM1) patients.

Main Results:

All calculated relaxation time variables were significantly elevated in DM1 patients versus controls.
A specific example shows relaxation time (40-60%) was 18.2 ms in controls vs. 40.1 ms in DM1 patients.
The developed relaxation variables demonstrated high discriminant capability.

Conclusions:

Force curve modeling offers an objective and effective method for myotonia quantification.
The proposed regression model provides a reliable tool for clinical myotonia assessment.
This approach overcomes previous limitations in measuring myotonia.