File Name: muscles and their movements .zip
- Human musculoskeletal system
- Introduction to the Muscular System
- Describing Skeletal Muscles: A Review of Muscle Attachments And Actions
- List of skeletal muscles of the human body
Human musculoskeletal system
The extraocular muscles are located within the orbit, but are extrinsic and separate from the eyeball itself. They act to control the movements of the eyeball and the superior eyelid. Functionally, they can be divided into two groups:. In this article, we shall look at the anatomy of the extraocular muscles — their attachments, innervation and actions.
The levator palpebrae superioris LPS is the only muscle involved in raising the superior eyelid. In contrast to the LPS, the superior tarsal muscle is innervated by the sympathetic nervous system. Fig 1 — Attachment of the levator palpebrae superiors to the superior tarsal plate. There are six muscles involved in the control of the eyeball itself. They can be divided into two groups; the four recti muscles, and the two oblique muscles.
There are four recti muscles; superior rectus, inferior rectus, medial rectus and lateral rectus. This is in contrast with the oblique eye muscles, which have an angular approach to the eyeball.
There are two oblique muscles — the superior and inferior obliques. Unlike the recti group of muscles, they do not originate from the common tendinous ring. From their origin, the oblique muscles take an angular approach to the eyeball in contrast to the straight approach of the recti muscles. They attach to the posterior surface of the sclera. The extraocular muscles are innervated by three cranial nerves. Damage to one of the cranial nerves will cause paralysis of its respective muscles.
This will alter the resting gaze of the affected eye. In this article, we shall look at the anatomy of the extraocular muscles - their attachments, innervation and actions. The name recti is derived from the latin for 'straight' - this represents the fact that the recti muscles have a direct path from origin to attachment. There are two oblique muscles - the superior and inferior obliques. Note the partial ptosis.
Horner's syndrome refers to a triad of symptoms produced by damage to the sympathetic trunk in the neck:. Horner's syndrome can represent serious pathology, such as a tumour of the apex of the lung Pancoast tumour , aortic aneurysm or thryoid carcinoma. Once you've finished editing, click 'Submit for Review', and your changes will be reviewed by our team before publishing on the site. Cookies help us deliver the best experience to all our users. The find out more about our cookies, click here.
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It is mandatory to procure user consent prior to running these cookies on your website. Levator Palpebrae Superioris The levator palpebrae superioris LPS is the only muscle involved in raising the superior eyelid.
It attaches to the superior tarsal plate of the upper eyelid a thick plate of connective tissue. The superior tarsal muscle located within the LPS is innervated by the sympathetic nervous system. By TeachMeSeries Ltd Muscles of Eye Movement There are six muscles involved in the control of the eyeball itself. Recti Muscles There are four recti muscles; superior rectus, inferior rectus, medial rectus and lateral rectus. Superior Rectus Attachments : Originates from the superior part of the common tendinous ring, and attaches to the superior and anterior aspect of the sclera.
Actions : Main movement is elevation. Also contributes to adduction and medial rotation of the eyeball. Actions : Adducts the eyeball. Actions : Abducts the eyeball. Clinical Relevance: Cranial Nerve Palsies The extraocular muscles are innervated by three cranial nerves. The affected eye is displaced laterally by the lateral rectus and inferiorly by the superior oblique. There is no obvious affect of the resting orientation of the eyeball. However, the patient will complain of diplopia double vision , and may develop a head tilt away from the site of the lesion.
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Introduction to the Muscular System
Synovial joints allow the body a tremendous range of movements. Each movement at a synovial joint results from the contraction or relaxation of the muscles that are attached to the bones on either side of the articulation. The degree and type of movement that can be produced at a synovial joint is determined by its structural type. While the ball-and-socket joint gives the greatest range of movement at an individual joint, in other regions of the body, several joints may work together to produce a particular movement. Overall, each type of synovial joint is necessary to provide the body with its great flexibility and mobility. There are many types of movement that can occur at synovial joints Table 9. Movement types are generally paired, with one directly opposing the other.
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At joints that permit adduction and abduction, muscles whose lines of action cross the medial side of a joint are adductors of that joint, and.
Describing Skeletal Muscles: A Review of Muscle Attachments And Actions
The muscular system is composed of specialized cells called muscle fibers. Their predominant function is contractibility. Muscles, attached to bones or internal organs and blood vessels, are responsible for movement.
The extraocular muscles are located within the orbit, but are extrinsic and separate from the eyeball itself.
List of skeletal muscles of the human body
The muscular system is an organ system consisting of skeletal , smooth and cardiac muscles. It permits movement of the body, maintains posture and circulates blood throughout the body. Together with the skeletal system , it forms the musculoskeletal system , which is responsible for movement of the human body. There are three distinct types of muscles: skeletal muscles , cardiac or heart muscles , and smooth non-striated muscles. Muscles provide strength, balance, posture, movement and heat for the body to keep warm. Skeletal muscles, like other striated muscles , are composed of myocytes , or muscle fibers, which are in turn composed of myofibrils , which are composed of sarcomeres , the basic building block of striated muscle tissue. Upon stimulation by an action potential , skeletal muscles perform a coordinated contraction by shortening each sarcomere.
1. Muscles Attach to Bones At Locations Called Origins and Insertions
By the end of this section, you will be able to identify the following muscles and give their origins, insertions, actions and innervations:. The skeletal muscles are divided into axial muscles of the trunk and head and appendicular muscles of the arms and legs categories. This system reflects the bones of the skeleton system, which are also arranged in this manner. Some of the axial muscles may seem to blur the boundaries because they cross over to the appendicular skeleton. The first grouping of the axial muscles you will review includes the muscles of the head and neck, then you will review the muscles of the vertebral column, and finally you will review the oblique and rectus muscles.
In the body, there are three types of muscle : skeletal striated , smooth, and cardiac. Skeletal muscle , attached to bones, is responsible for skeletal movements. The peripheral portion of the central nervous system CNS controls the skeletal muscles. Thus, these muscles are under conscious, or voluntary, control. The basic unit is the muscle fiber with many nuclei. These muscle fibers are striated having transverse streaks and each acts independently of neighboring muscle fibers. Smooth muscle , found in the walls of the hollow internal organs such as blood vessels, the gastrointestinal tract , bladder , and uterus , is under control of the autonomic nervous system.
Human muscle system , the muscles of the human body that work the skeletal system , that are under voluntary control, and that are concerned with movement, posture, and balance.
The human musculoskeletal system also known as the human locomotor system , and previously the activity system  is an organ system that gives humans the ability to move using their muscular and skeletal systems. The musculoskeletal system provides form, support, stability, and movement to the body. It is made up of the bones of the skeleton , muscles , cartilage ,  tendons , ligaments , joints , and other connective tissue that supports and binds tissues and organs together. The musculoskeletal system's primary functions include supporting the body, allowing motion, and protecting vital organs.
This is a table of skeletal muscles of the human anatomy. There are around skeletal muscles  within the typical human body. Nevertheless, the exact number is difficult to define because different sources group muscles differently, e.