The Muscular and the Nervous System Integration in the Hand
The human hand contains a lot of muscles. Every muscle is a flexible structure filled with thousands of tiny smooth muscle cells. Numerous tiny threads, known as fibrils, make up each fiber. Nerve cell signals manage each muscle fiber’s relaxation. The quantity of fibers in a muscle significantly impacts its performance. The hand produces adenosine triphosphate (ATP), which muscle cells convert into kinetic motion to power muscles in the hand to allow it to carry out different activities.
Skeletal muscles in the hand allow it to move and be located at different angles and positions. They provide the human body with its form and protect the bones. Skeletal muscles act in groups because they can only move in one way. Movement is made more accessible when one of the pair’s muscles flexes, causing the other to stretch.
Powerful tendons that either link directly with the bones or hook to them are where the muscles are attached. The tendons’ extension over the joints aids in maintaining the stability of the joints (Ostrovidov et al., 2019). A healthy individual can voluntarily manage their skeletal muscles. The skeletal muscles relax to produce the majority of outwardly observable hand motions, including closing and opening of fingers, up and downward movements, and lifting of objects. All movements by the hand are, therefore, controlled by skeletal muscles.
To keep the hand’s position in place, skeletal muscles constantly make minute changes. They fix an individual’s hand in one place while in relaxation mode. They maintain the joints in the proper alignment along with the fibers to prevent them from dislocating (Tortora et al., 2018). When they stretch and relax, skeletal muscles also produce heat, which aids in regulating body temperature in the arm area. The hand generates a lot of its heat through muscle movement.
Blood arteries and skeletal muscles control hand motion. People do not even realize they use these muscles; they do it naturally. Skeletal muscles require a cognitive mind to allow the hand to sense and function properly. Skeletal muscle compressions are necessary for many distinct muscle activities. They include the contraction of the fibers in the hand when someone stretches, the upward and downward movement of the hand when someone lifts a heavy object, and the overall degree of movement of the hand.
The neurological system, which governs the human body and endocrine glands, causes muscle movement. They are in charge of maintaining the internal hand’s stability and coordinating all operations in the hand region. The fundamental building block of the neurological system is a network of neurons or synapses. Motor neurons are the name for the cells that support muscular (Weberruss et al., 2018). The body and extensions of a neuron make it up. Nerve cells are the shorter ones, and axons are the longer ones.
The neurons in the hand region can receive impulses from the brain through the dendrites. The information that has been digested is subsequently transmitted to neighboring cells through the axon (e.g., muscle cells). Through adjustments in the tension across the cell surface, or “action potential,” the signal is further distributed along the neuron. Afterward, chemical agents protect the information flow between particular cells in the brain.
The mediator is produced once the action potential hits an axon’s terminus in the hand, and the hand behaves according to the central nervous system’s response. The brain and spinal cord are the central nervous system’s two principal components (CNS). The brain is linked to 12 pairs of head nerves comprising the central nervous system, while the spinal cord is interconnected to 31 spinal nerves.
The autonomic nervous system supervises the internal organs’ functions. It is compelled and comprises sympathetic and parasympathetic systems, all of which work to maintain the human hand’s functioning equilibrium with the potential for either system to take precedence in particular circumstances. When the hand moves, the sympathetic nervous system takes over, whereas when they are relaxing, the parasympathetic system takes over (Weberruss et al., 2018). The parasympathetic nervous system has the reverse effect, i.e., it decreases hand activities, whereas the sympathetic nervous system increases hand activity (e.g., increases in HR and BP) (decrease in HR).
How a Stroke Affects the Integration of the Muscular and the Nervous Systems Around the Hand Region
A stroke is a severe brain disease resulting from a disruption of the blood flow and can harm the neurological and muscular systems. Depending on the extent of the brain injury experienced by a stroke sufferer, different disabilities may show in different ways. The majority of the time, however, there are certain general signs. Psychomotor agitation is one of the effects of stroke from the standpoint of its impact on the neurological system. Individuals can exhibit excessive irritability, panic attacks, or other emotional disorders because a specific section of the brain is injured, which makes it challenging to manage actions.
Numbness of the hand is a sign of a stroke in the neurological system (Kuo & Hu, 2018). Brain injury makes it impossible for an individual to manage nerves around the hand region, which makes it impossible to stretch specific hand muscles and nerves. Therefore, the hand either entirely or partially quits reacting to outside stimuli.
Additionally, specific sensory capabilities may be compromised depending on the part of the brain that has been damaged. Patients with stroke frequently lose the ability to sense cold to hot things. Motor deprivation also affects the central nervous system since it reduces the volume of nerve signals flowing through the hand. Thus, a stroke can be described as a severe condition that impacts not only the hand but also various body systems and might result in the irreparable disturbance of various processes.
A high muscular tone and rising tensions are referred to as hypertonia. Usually, it happens when a stroke destroys the region of the brain that communicates with the movements to control them (Kuo & Hu, 2018). These impulses tell the muscles to relax as necessary in regular muscular function. There is much stress as a response since the muscles are constantly firing.
After a stroke, hypertonia frequently impacts the hands. For instance, if the patient’s hand is affected, the arm may flex and pull inward towards the body. It also frequently affects the hand, causing it to tighten into a fist.
Contractures may form if hypertonia goes untreated for an extended period. Contractures happen when a muscle, nerve, tissue, or skin strand shrinks and stiffens. As a result, there is a reduction in mobility range and a limitation of functionality. While they can happen in the hand region, they result in numbness and reduced sensitivity.
A stroke is a severe medical emergency that poses a life-threatening risk since it is the brain’s equivalent of cardiac arrest. Strokes are especially time-sensitive, and delayed treatment can result in death or severe brain injury. It can be scary for individuals experiencing a stroke or those close to them.
However, the range of stroke treatments is growing daily thanks to developments in brain research, scanning technology, and novel pharmaceuticals. It is crucial to seek prompt medical assistance if an individual exhibits indications of a stroke. A stroke victim’s chances of having its consequences reduced or reversed increase the quicker they receive medical attention.
References
Kuo, C. L., & Hu, G. C. (2018). Post-stroke spasticity: A review of epidemiology, pathophysiology, and treatments. International Journal of Gerontology, 12(4), 280-284.
Ostrovidov, S., Salehi, S., Costantini, M., Suthiwanich, K., Ebrahimi, M., Sadeghian, R. B.,… & Khademhosseini, A. (2019). 3D bioprinting in skeletal muscle tissue engineering. Small, 15(24), 1805530.
Tortora, G. J., & Derrickson, B. H. (2018). Principles of anatomy and physiology. John Wiley & Sons.
Weberruss, H., Maucher, J., Oberhoffer, R., & Mueller, J. (2018). Recovery of the cardiac autonomic nervous and vascular system after maximal cardiopulmonary exercise testing in recreational athletes. European journal of applied physiology, 118(1), 205-211.