What is the anatomical definition of the origin and insertion of a muscle?
- Origin = proximal attachment
- insertion = distal attachment
- Origin is not stationary, moveable of attachments can be used as a definition
- More distal is usually more moveable but not always.
What are the forces that normally produce motion at a joint?
1. Gravity, 2. Muscle contraction
What do we call the force that causes a specific desired motion?
Agonist or prime mover
What do we call a muscle that causes a motion opposite to the desired motion?
Antagonist—opposes the motion you are talking about.
What are the functions of synergistic muscles?
Work together with the prime mover—they stabilize joints around the joint that’s moving, neutralizes unwanted movements of the prime mover
What do we call the basic functional units that make up each muscle?
What is the definition of a motor unit?
Alpha motor neuron and all the fibers that it supplies
Three types of muscular contraction:
- 1. Isometric—same length
- 2. Isotonic(concentric)—shortening
- 3. Eccentric—lengthening contraction
2 major parts of CNS
–brain and spinal cord
What is a peripheral nerve?
- All the nerves that are located outside the central nervous system
- --made up of different axons that belong to neurons, Swann cells(supporting cells), connective tissue shealths
a) What is a cranial nerve?
Nerves that exit the CNS/brain
b)What is a spinal nerve?
Nerves that arise from the spinal cord
How is a gross spinal nerve formed?
Dorsal and Ventral roots(made of rootlets) emerge from gray matter (gray matter shaped like butterfly)
How long is a typical spinal nerve and how does it terminate?
Only about a cm, branches into a ventral ramus (larger) and a dorsal ramus (smaller)
What are the 2 general kinds of terminal branches of peripheral nerves that are derived from the rami?
- Muscular branches and cutaneous branches which innervate the skin (goes past the muscles, and branch off to supply the skin)
- Myotomes are made up of muscles
- dermatomes= skin
What is meant y the terms “afferent” and “efferent” nerve fibers?
- Afferent is towards the CNS (sensory!)
- Efferent is away (motor!)
What are the major functional kinds of nerve fibers found in:
- a) dorsal roots? Sensory
- b) ventral? Motor
- c) spinal nerves? Both
- d) dorsal rami? Both
- e) ventral rami? Both
Where are nerve cell bodies located for afferent and efferent nerve fibers?
- Afferent: dorsal root ganglion (collection of sensory cell bodies)
- Efferent: Spinal cord gray matter within ventral horn
Somatic: Skeletal muscle, body wall and extremities, (bones joints, ligaments, cartilage)
Visceral: Internal, internal organs, structures internally and within the skin like glands and smooth muscle (like in GI tract)
4 basic functional fiber types are found in a typical spinal nerve.
What functional fiber types do each of the following abbreviations represent?
SE, VE, SA, VA
- VE—visceral efferent
- SA—Somatic afferenct—sensory of skin, sensatory, fibers that innovate mus
- VA—Visceral afferent—blood vessels, pressure receptors, chemo receptors, etc
What is a dermatome?
- *Area of skin that is innovated by a single spinal nerve.
- ***use diagram in notes**--nerves do overlap so ether side dermatomes of adjacent nerves
- if lesion in spinal nerve, only a small area that is complete loss of sensation.
- 2 components: dermatome supplied by both the dorsal and the ventral ramus of its spinal nerve. If entire dermatome is numb than the spinal nerve has lesion. If one little part is numb, only one part of the rami is affected.
What factors determine which areas appear black vs white?
- 1. Density of the tissues
- 2. Super-imposition
- 3. Tissue thickness
Normal PA Chest X-Ray—No pathology
- -Posterior/Anterior: x-ray is going through posterior (patient has back to the x-ray).
- -X-ray is always posted as if you were looking at the patient
- -2D image of a 3D image—all compressed both into a single image.
- However, anterior structures are seen more clearly.
Which side of the films and right sdies of paitent—always viewed as if facing patient
What is meant by the term “radiolucent”?
What is meant by the term “radiodense” or “radiopaque”?
Very white—absorbed by the tissue
What are the five major categories of radiodense materials normal see in the plain film x-rays?
- 1. Air or gas
- 2. Fat
- 3. Soft tissue (muscle, internal organs)
- 4. Bone
- 5. Metal
Normal—PA, can see the anterior images better
AP view—can see the posterior parts of the better
How can hollow soft tissue structures or organs be visualized with conventional radiography? Contrst meterials—can be radiolucent or radiodense
- Barrium (radiodense)—positive contrast material is radiodense
- Positive and Negative—ex: barium introduced first so as barium past out, air was introduced so can see the residue barium outline walls/ Fluid line= patient was laying on side
Advantages of CT conventional radiography?
- -Eliminates the superimposition
- -see the tissues that have margerate densities in more detail
Bony elements and regions(subdivions) of the Upper Limb (overview)
-shoulder joint, acromionclvicular joint, sternoclavicular joint\
Shoulder Region(anterior view)
- 1. clavicale
- 2. Sternoclavicular—only bony attachment of the upper limb with w axial skeleton
- 3. Scapula; lies posterior to the ribs
- 4. Acromins