Heel Skin Mechanoreceptors, Plantar Flexion Contraction Force
Conditions
Keywords
Skin mechanoreceptor, Ruffini corpuscle, Pacinian corpuscle, Contraction forcee
Brief summary
Previous studies have shown that stimulation of heel skin mechanoreceptors facilitates the soleus H-reflex, whereas stimulation of metatarsal region mechanoreceptors inhibits the soleus H-reflex. From this perspective, plantar cutaneous receptors may play an important role in the regulation of activities such as walking and running, as well as in the control of spasticity in patients with upper motor neuron lesions. Investigating the effect of heel skin mechanoreceptors on plantar flexor muscle contraction force may provide valuable insight into the potential influence of these mechanoreceptors on locomotor activities and muscle tone, and may offer a foundation for future studies directly addressing these topics.
Detailed description
The aim of this study is to investigate the effect of heel skin mechanoreceptors on plantar flexor contraction force. The plantar flexor muscle strength of the participants was evaluated using a force sensor connected to a computer. For the isometric muscle strength measurement, the subjects were asked to perform maximal plantar flexion for 10 seconds. A 5-pulse stimulation package at 15% contraction level was delivered 10 times with a 4-6 second interval. The measurements were repeated 10 times with a 30-second interval. During the plantar flexion muscle strength measurement, the heel skin mechanoreceptors were stimulated at sensory threshold by a square wave electrical current with a pulse duration of 1 microsecond.
Interventions
OTHERAssesment of Plantar Flexion Muscle Strength During Heel Skin Mechanoreceptor Stimulation
For the measurement of isometric muscle strength, participants lying prone on an examination table were instructed to perform maximal plantar flexion for 10 seconds. To achieve a submaximal contraction corresponding to 15% of their maximal contraction force, they were asked to follow the 15% threshold reference line displayed on the force channel on the screen. During the measurement of plantar flexion muscle strength, the cutaneous mechanoreceptors of the heel were stimulated with a square-wave electrical current with a pulse duration of 1 microsecond, at an intensity three times the sensory threshold. Electrical stimulation was delivered via a constant-current stimulator (Digitimer DS7A, Hertfordshire, United Kingdom). At the 15% contraction level, a train of five stimuli was delivered 10 times at intervals of 4-6 seconds. Measurements were repeated 10 times with 30-second intervals between each set.
Sponsors
Istanbul Physical Medicine Rehabilitation Training and Research Hospital
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Intervention model description
For the measurement of isometric muscle strength, participants lay prone on an examination table and were instructed to perform maximal plantar flexion for 10 seconds. To achieve a submaximal contraction corresponding to 15% of their maximal voluntary contraction, participants were asked to follow a 15% threshold reference line displayed on the force channel monitor.During the measurement of plantar flexion muscle force, heel skin mechanoreceptors were stimulated using a square-wave electrical current with a pulse duration of 1 microsecond at an intensity three times the sensory threshold. Electrical stimulation was delivered via a constant-current stimulator (Digitimer DS7A, Hertfordshire, United Kingdom). At the 15% contraction level, a train of five stimuli was delivered 10 times at intervals of 4-6 seconds. Measurements were repeated 10 times with 30-second intervals between each set.
Eligibility
Sex/Gender
MALE
Age
20 Years to 40 Years
Healthy volunteers
Yes
Inclusion criteria
* Being healthy * Being between 20 and 40 years of age * Being female or male * Volunteering to participate
Exclusion criteria
* Having a history of orthopedic conditions-particularly in the lower extremity-or residual neuromusculoskeletal problems due to previously experienced illnesses
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Voluntary Contraction Force | Day 1 (During a single experimental session) | While the participants were lying prone on the examination table, plantar flexion muscle strength was assessed using a computer-connected force sensor (SPIKE 2.7). For detailed analysis of the participant data using the SPIKE 2.7 force sensor software, an IIR digital filtering process was first applied to the force channel. During this procedure, a low-pass filter was selected. The filter settings were configured with a cutoff value of 100 and an order of 2. As a result of this filtering process, the newly generated filtered memory channel was labeled "ForceLP." Subsequently, the waveform average of the ForceLP channel was calculated with the following settings: width 4 s, offset 2 s, and trigger set to 6 stimuli (event+). From these averaged traces peak contraction force was determined. |
| Reflex Contraction Force | Day 1 (During a single experimental session) | While the participants were lying prone on the examination table, plantar flexion muscle strength was assessed using a computer-connected force sensor (SPIKE 2.7). For detailed analysis of the participant data using the SPIKE 2.7 force sensor software, an IIR digital filtering process was first applied to the force channel. During this procedure, a low-pass filter was selected. The filter settings were configured with a cutoff value of 100 and an order of 2. As a result of this filtering process, the newly generated filtered memory channel was labeled "ForceLP." Subsequently, the waveform average of the ForceLP channel was calculated with the following settings: width 4 s, offset 2 s, and trigger set to 6 stimuli (event+). From these averaged traces reflex contraction force was determined. |
| Reflex Contraction Latency | Day 1 (During a single experimental session) | While the participants were lying prone on the examination table, plantar flexion muscle strength was assessed using a computer-connected force sensor (SPIKE 2.7). For detailed analysis of the participant data using the SPIKE 2.7 force sensor software, an IIR digital filtering process was first applied to the force channel. During this procedure, a low-pass filter was selected. The filter settings were configured with a cutoff value of 100 and an order of 2. As a result of this filtering process, the newly generated filtered memory channel was labeled "ForceLP." Subsequently, the waveform average of the ForceLP channel was calculated with the following settings: width 4 s, offset 2 s, and trigger set to 6 stimuli (event+). From these averaged traces reflex contraction latency was determined. |
Countries
Turkey (Türkiye)
Outcome results
None listed