The human musculoskeletal system (also known as locomotor system , and formerly the activity system ) is an organ system that gives humans the ability to move using the muscular system and their framework. The musculoskeletal system provides form, support, stability, and movement to the body.
It consists of skeletal bones, muscles, cartilage, tendons, ligaments, joints, and other connective tissues that support and bind tissues and organs together. The main functions of the musculoskeletal system include supporting the body, enabling movement, and protecting vital organs. The bone portion of the system serves as the primary storage system for calcium and phosphorus and contains an important component of the hematopoietic system.
This system explains how bones connect to bones and other muscle fibers through connective tissue such as tendons and ligaments. Bone provides stability to the body. The muscle keeps the bone in place and also plays a role in bone movement. To enable movement, different bones are connected by joints. Cartilage prevents the ends of the bones rubbing directly from one another. Muscles contract to move bones attached to joints.
However, diseases and disorders may affect the overall function and effectiveness of the system. These diseases can be difficult to diagnose because of the close relationship of the musculoskeletal system to other internal systems. The musculoskeletal system refers to a system that has muscles attached to the internal skeletal system and is necessary for humans to move to a more favorable position. Complex problems and injuries involving the musculoskeletal system are usually handled by a physiotherapist (a specialist in physical medicine and rehabilitation) or an orthopedic surgeon.
Video Human musculoskeletal system
Subsistem
Skeletal
The skeletal system serves many important functions; It provides forms and shapes for the body, support and protection, enables body movement, produces blood for the body, and stores minerals. The amount of bone in a human skeleton system is a controversial topic. Man is born with more than 300 bones; However, many bones join together between birth and maturity. As a result, the average adult skeleton consists of 206 bones. The amount of bone varies according to the method used to get the count. While some people consider a particular structure as a single bone with many parts, others may see it as a part with many bones. There are five general classifications of bone. These are long bones, short bones, flat bones, irregular bones, and sesamoid bone. The human skeleton consists of a unified bone and an individual supported by ligaments, tendons, muscles and cartilage. It is a complex structure with two distinct divisions; axial skeleton , which includes vertebral columns, and appendicular framework .
Function
The skeletal system functions as a framework for tissues and organs to attach itself. This system functions as a protective structure for vital organs. The main example of this is the brain that is protected by skulls and lungs protected by ribs.
Located on the long bones are two differences in bone marrow (yellow and red). The yellow marrow has fatty connective tissue and is found in the marrow cavity. During starvation, the body uses the fat in the yellow marrow for energy. The red marrow of some bones is an important site for the production of blood cells, about 2.6 million red blood cells per second to replace the existing cells that have been destroyed by the liver. Here all erythrocytes, platelets, and most leukocytes are formed in adults. From red marrow, erythrocytes, platelets, and leukocytes migrate to the blood to perform their specific tasks.
Another bone function is the storage of certain minerals. Calcium and phosphorus are one of the major minerals stored. The importance of this "device" of storage helps regulate the mineral balance in the bloodstream. When mineral fluctuations are high, these minerals are stored in bone; when it is low it will be pulled from the bone.
Muscular
There are three types of muscles - the heart, the bones, and the smooth. Smooth muscles are used to control the flow of substances within the hollow organ lumen, and are not consciously controlled. Skeletal and cardiac muscles have a striation seen under a microscope because of the components inside their cells. Only skeletal and fine muscles are part of the musculoskeletal system and only skeletal muscle can move the body. Cardiac muscle is found in the heart and is only used to circulate blood; like smooth muscle, these muscles are not under conscious control. Skeletal muscle is attached to the bone and arranged in opposite groups around the joint. The muscles are innervated, to communicate nerve energy to, by the nerves, that conduct electrical current from the central nervous system and cause the muscles to contract.
Initiation of contraction
In mammals, when muscles contract, a series of reactions occur. Muscle contractions are stimulated by motor neurons that send messages to the muscles of the somatic nervous system. Depolarization of motor neurons produces neurotransmitters that are released from nerve terminals. The space between nerve terminals and muscle cells is called the neuromuscular junction. These neurotransmitters diffuse across the synapse and bind to specific receptor sites on the muscle fiber muscle membrane. When the receptors are sufficiently stimulated, the action potential is generated and the permeability of the sarcolemma is changed. This process is known as initiation.
Tendons
Tendons are a strong and flexible fibrous connective tissue that connects muscle to bone. An extra-cellular connective tissue between muscle fibers binds to the tendon at the distal and proximal end, and the tendon binds to the individual bone periosteum at the origin and insertion of the muscle. When the muscle contracts, the tendon sends strength to the relatively stiff bone, pulling it and causing movement. Tendons can stretch substantially, allowing them to function as spring during movement, thus saving energy.
Joints, ligaments and bursae
Joints
Joints are structures that connect individual bones and allow bones to move against each other to cause movement. There are three divisions of joints, diarthroses that allow for wide mobility between two or more articular heads; amphiarthrosis, which is a joint that allows multiple motions, and false joints or syncrocesses, immobilized joints, which allow little or no movement and are mostly fibrous. Synovial joints, joints that are not directly joined, are lubricated by a solution called synovial fluid produced by the synovial membrane. This fluid lowers friction between the articular surface and is deposited in an articular capsule, binding joints with tight tissue.
Ligaments
Ligaments are small bands of dense, white, and fibrous elastic tissue. Ligaments connect the ends of bones together to form joints. Most ligaments restrict dislocations, or prevent certain movements that may cause fractures. Because they are only elastic, they progressively extend when under pressure. When this happens, the ligaments may be susceptible to fractures resulting in unstable joints.
Ligaments can also limit some of the actions: movements such as hyper extension and hyper flexion are limited by ligaments to where. Also ligaments prevent movement of certain direction.
Bursae
A bursa is a small fluid-filled sac made of white fibrous tissue and coated with a synovial membrane. The exchange may also be formed by a synovial membrane that extends outside the joint capsule. It provides a bearing between the bones and the tendons and/or muscles around the joint; bursa filled with synovial fluid and found in almost every major joint of the body.
Maps Human musculoskeletal system
Clinical interests
Because many other body systems, including the vascular, nervous, and cover system, are interconnected, the interference of one of these systems can also affect the musculoskeletal system and complicate the diagnosis of the origin of the disorder. Diseases of the musculoskeletal system mostly include functional disorders or motion non-conformities; the extent of damage depends specifically on the problem and its severity. In an in-patient study in the United States, the most common OR procedure in 2012 involves the musculoskeletal system: knee arthroplasty, laminectomy, hip replacement, and spinal fusion.
Articular (or joint-related) disorders are the most common. However, also among the diagnoses are: primary, neurological muscle disease (related to medical science related to the nervous system and disorders that affect it) deficits, toxins, endocrine disorders, metabolic disorders, infectious diseases, blood and blood vessel disorders, and nutrients imbalance.
Muscle disorders of other body systems can cause irregularities such as: impaired motion and ocular control, respiratory dysfunction, and bladder damage. Absolute paralysis, paresis, or ataxia can be caused by major muscle dysfunction of infection or toxic origin; However, major disorders are usually associated with the nervous system, with the muscular system acting as an effector organ, an organ capable of responding to stimuli, particularly nerve impulses.
One unpretentious disorder that begins during pregnancy is pelvic pelvic pain, is complex and multi-factorial and tends to be also represented by a series of pain-induced sub-groups of the peripheral or central nervous system, altering muscle weakness/stiffness, laxity for injury tendinous structures/ligaments for 'mal-adaptive' body mechanics.
See also
- Human skeletal muscle
- Skeletal muscle
- Muscle system
References
Source of the article : Wikipedia