Showing posts with label biomechanics. Show all posts
Showing posts with label biomechanics. Show all posts
Friday, June 19, 2009
Monday, May 11, 2009
biomechanics: arthrokinematics
this unit covered some of the basic ideas about arthrokinematics: the study of the motions that occur within joint spaces during bone movements. joints in the body are in general in a convex/concave relationship, which allows for greater surface area for the area of bone which are in contact with each other; increasing joint stability, dissipating contact forces, and providing more guidance for the motion.
the different motions possible in such a joint are: roll, slide, spin, distraction, compression, and longitudinal traction. rolling occurs when multiple points on one bone contacts with multiple points on the other, as in the femoral condyles on the tibial plateau. sliding occurs when a single point on one bone contacts multiple points on another, as in the carpal bones sliding on the facet joints. spinning is when a single point on bone rotates on a single point of another, such as the radial head rotating at the humeroradial joint during supination / pronation. distraction is the separation of joint spaces and compression is the reduction of space between the bones of the joint. longitudinal traction is distraction of the joint in a longitudinal direction; parallel to the length of the body.
convex on concave motion describes a joint in which the concave bone is fixed-- when the convex bone rotates, it also slides in the opposite direction so as to stay engaged in the joint. concave on convex motion describes the opposite scenario, where a convex bone is fixed and the concave rotation produces a sliding motion in the same direction.
most motions at real joints are actually dynamic combinations of the above mentioned motions. for example, at the glenohumeral joint, the rolling upward of the humerus during abduction is combined with spinning and sliding. likewise, at the knee joint, extension combines rolling, sliding, and spinning (which helps locks the knee at its fullest extension) and flexion also combines the same motions.
questions
1. what are the advantages to having a convex-concave joint configuration?
2. describe the "roll" motion in joints and give an example.
3. describe the "slide" motion and give an example.
4. describe the "spin" motion and give an example.
5. describe the "distraction and longitudinal traction" motions.
6. describe the "compression" motion.
7. what happens in convex-on-concave motion?
8. what happens in concave-on-convex motion?
9. what types of motions occur at the glenohumeral joint?
10. describe the motion that occurs at the knee in a "convex on concave" setting.
11. describe the motion that occurs at the knee in the "concave on convex" setting.
answers
1. the increased surface area for contact allows for greater stability, guided motion, and a dissipation of contact forces.
2. multiple points on one bone contact multiple points on another bone, such as the femoral condyles on the tibial plateaus.
3. few points on one bone contact multiple points on another bone, such as carpal bones on the facet surfaces.
4. one point on one bone rotating on one point on another-- like the head of the radius at the humeroradial joint during supination/pronation.
5. both refer to separating the bones within the joint / increasing the joint space. longitudinal traction is a type of distraction which moves the bone parallel to the body, longitudinally.
6. decreasing the space between the bones within the joint.
7. when the concave end is fixed, the convex end slides in the opposite direction of the rotation motion.
8. when the convex end is fixed, the concave end slides in the same direction of the rotation motion.
9. roll, spin, slide.
10. roll, slide, spin.
11. still roll, slide, spin.
the different motions possible in such a joint are: roll, slide, spin, distraction, compression, and longitudinal traction. rolling occurs when multiple points on one bone contacts with multiple points on the other, as in the femoral condyles on the tibial plateau. sliding occurs when a single point on one bone contacts multiple points on another, as in the carpal bones sliding on the facet joints. spinning is when a single point on bone rotates on a single point of another, such as the radial head rotating at the humeroradial joint during supination / pronation. distraction is the separation of joint spaces and compression is the reduction of space between the bones of the joint. longitudinal traction is distraction of the joint in a longitudinal direction; parallel to the length of the body.
convex on concave motion describes a joint in which the concave bone is fixed-- when the convex bone rotates, it also slides in the opposite direction so as to stay engaged in the joint. concave on convex motion describes the opposite scenario, where a convex bone is fixed and the concave rotation produces a sliding motion in the same direction.
most motions at real joints are actually dynamic combinations of the above mentioned motions. for example, at the glenohumeral joint, the rolling upward of the humerus during abduction is combined with spinning and sliding. likewise, at the knee joint, extension combines rolling, sliding, and spinning (which helps locks the knee at its fullest extension) and flexion also combines the same motions.
questions
1. what are the advantages to having a convex-concave joint configuration?
2. describe the "roll" motion in joints and give an example.
3. describe the "slide" motion and give an example.
4. describe the "spin" motion and give an example.
5. describe the "distraction and longitudinal traction" motions.
6. describe the "compression" motion.
7. what happens in convex-on-concave motion?
8. what happens in concave-on-convex motion?
9. what types of motions occur at the glenohumeral joint?
10. describe the motion that occurs at the knee in a "convex on concave" setting.
11. describe the motion that occurs at the knee in the "concave on convex" setting.
answers
1. the increased surface area for contact allows for greater stability, guided motion, and a dissipation of contact forces.
2. multiple points on one bone contact multiple points on another bone, such as the femoral condyles on the tibial plateaus.
3. few points on one bone contact multiple points on another bone, such as carpal bones on the facet surfaces.
4. one point on one bone rotating on one point on another-- like the head of the radius at the humeroradial joint during supination/pronation.
5. both refer to separating the bones within the joint / increasing the joint space. longitudinal traction is a type of distraction which moves the bone parallel to the body, longitudinally.
6. decreasing the space between the bones within the joint.
7. when the concave end is fixed, the convex end slides in the opposite direction of the rotation motion.
8. when the convex end is fixed, the concave end slides in the same direction of the rotation motion.
9. roll, spin, slide.
10. roll, slide, spin.
11. still roll, slide, spin.
Saturday, May 9, 2009
biomechanics: functional neuro-muscular units
this chapter covered the basics of muscle contraction, the neuromuscular junction, and the prioprioceptors involved in reflex loops. a review of the skeletal muscle structural hierarchy: skeletal muscle is surrounded by epimysium connective tissue and contains bundles of fascicles, which are surrounded by perimysium and contain muscle fibers, which are surrounded by endomysium and contain myofibrils, which are surrounded by sarcoplasmic reticulum and are composed of the basic contractile unit of muscles, the sarcomeres, which are made up of thin and thick filaments.
the neuromuscular junction is the site at which the motor neuron synapses with the muscle, at the motor plate. muscle contraction occurs when an action potential propagates down to the end of the axon, which causes release of acetylcholine, which migrates to the motor plate and binds to receptor channels, causing a membrane potential which propagates down the t tubules of the myofibrils, causing release of calcium from the terminal cisternae of the sarcoplasmic reticulum, which initiates the contraction of the myofilaments. relaxation occurs which calcium is sequested back into the sarcoplasmic reticulum and acetylcholine esterase breaks down the acetylcholine that was released into the NMJ.
muscle contraction can be classified in several different manners depending on frequency, intensity, and relaxation between contractions. a twitch is a single contraction and a full relaxation. within a twitch there are three stages: the latent, contraction, and relaxation phase. "treppe" is repeated contractions of increasing intensity with a return to full relaxation in between. "wave summation" is similar to treppe but without the full relaxation in between. "tetanus" is a higher frequency, maximal intensity contraction with barely any or no relaxation in between contractions.
there are several different types of axons which provide motor and sensory innervation to muscles. A-alpha, thickest and fastest conducting, seen in motor efferents and muscle spindle receptor afferents. A-beta, seen in touch and pressure mechanoreceptor afferents. A-gamma, seen in muscle spindle efferents. A-delta, seen in skin temperature and pain afferents. B fibers, seen in sympathetic preganglionics, and C fibers (unmyelinated), seen in sympathetic postganglionics.
there are three main types of proprioceptors: muscle spindles receptors, golgi tendon organs, and joint kinesthetic organs. muscle spindles are located within the muscle belly (called "extrafusal fibers") and are composed of intrafusal fibers, either "bags" or "chains", which are wrapped with a sensory nerve ending. nuclear bag fibers have contractile ends that are attached to the extrafusal fibers, nuclei in the center of the fiber, and detect fast changes in muscles length-- whereas nuclear chain fibers are attached to the nuclear bag fibers themselves and detect slow, steady chains. primary "Ia" sensory endings are wrapped around the center of spindle receptors and respond to change in muscle length; secondary "flower spray" sensory endings are slower conducting and respond to the overall length of the fiber.
spindle receptors are involved in both rapid adjustments to maintain balance as well as slower adjustments to maintain posture. the reflex they are involved in is called the "quick stretch reflex"-- extrafusal muscle causes stretching of the muscle spindle, which activates the primary or secondary nerve, which activates an interneuron which activates the motor innervation of the muscle itself-- in essence providing a balancing / feedback system for quickly contracting muscles. spindle receptors also mediate the reciprocal inhibition reflex pathway, which inhibit the antagonist muscles.
golgi tendon organ receptors are embedded within the tendon of the muscles and are involved in a complementary reflex loop- at the extremes of contraction, when tension is high in the tendon of the muscle, golgi tendon organs stimulate 1b sensory nerves, which activate the inhibitory interneurons for the muscle, causing it to relax (while simultaneously activating the antagonist muscles).
the third type of proprioceptor is the joint kinesthetic receptor, which are located within joints and detect joint movement, tension, and angle. pacinian corpuscles are located within connective tissue and sense rapid pressure changes, stretch, and acceleration of the joint motion. ruffini corpuscles are located in synovial capsules and ligaments and sense deep/rapid sustained pressure, lateral stretch, and joint angle changes. free nerve endings are found throughout and sense both rapid and sustained pressure.
questions
what are these functional units surrounded by and what do they contain?
1. skeletal muscle
2. muscle fascicle
3. muscle fiber
4. myofibril
5. sarcomere
NMJ...
6. what is a neuromuscular junction?
7. what are "motor points" and where are they generally?
8. what is the neurotransmitter that is released from axons at the NMJ?
9. what is involved in the relaxation of a muscle in the NMJ?
10. describe the process of contraction starting from release of neurotransmitter from the axon at the NMJ.
11. describe the process of muscle relaxation.
contraction types...
12. what is a "motor unit"?
13. what are examples of small and large motor units?
14. what is a muscle "twitch"?
15. what is a "treppe"?
16. what is a "wave summation"?
17. what is "tetanus"?
18. what is the difference between incomplete and complete tetanus?
19. what are the three phases to the muscle twitch?
axonal classifications...
20. what are three types of neurons?
21. describe the A-alpha classification of nerve fiber.
22. ...A-beta.
23. ...A-gamma.
24. ...A-delta.
25. ...B fibers.
26. ...C fibers.
27. what are the 5 components to a spinal cord reflex arc?
spindles...
28. what are the three types of proprioceptors?
29. where are muscle spindle receptors located? what do they measure?
30. what are intrafusal and extrafusal fibers?
31. what are the two types of intrafusal fibers and what is the difference between them?
32. what are the two types of sensory neurons from muscle spindle receptors and what is the difference between them?
33. what are the two types of responses to stretch that muscle spindle receptors are involved in?
34. describe the role of gamma motor neurons in maintaining balance.
golgi tendon organs...
35. what are golgi tendon organs?
36. what do golgi tendon organs detect?
37. describe how a golgi tendon organ can protect a muscle from damage.
38. describe the two types of stretch responses that a golgi tendon organ can be involved in.
joint kinesthetic receptors...
39. what are the three types of joint kinesthetic receptors?
40. what do joint kinesthetic receptors sense?
41. describe the different locations and functions of the different types of joint kinesthetic receptors.
proprioceptors affect on reflex muscle tone...
42. what are the three types of reflexes that proprioceptors mediate?
43. describe the quick stretch reflex.
44. describe the reciprocal inhibition reflex.
answers
1. surrounded by epimysium, contains muscle fascicles.
2. surrounded by perimysium, contains muscle fibers.
3. surrounded by endomysium, contains myofibrils.
4. surrounded by sarcoplasmic reticulum, consists of sarcomeres.
5. contains thick and thin filaments.
6. where a motor nerve synapses with a muscle fiber.
7. the actual point at which the nerve synapses- generally in the center of the muscle belly.
8. AcH.
9. breakdown of AcH by AcHesterase.
10. acetylcholine released from axon into NMJ, which bind to receptors on motor end plate and creates action potential, which propogates through the t tubules, causing calcium to be released from sarcoplasmic reticulum, which initiates the contraction of the myofilaments by binding to troponin and exposing binding sites on tropomyosin.
11. calcium is sequestered into the sarcoplasmic reticulum, acetylcholine broken down by esterase in the NMJ.
12. a nerve and all the muscle fibers it innervates.
13. extraocular muscles (20 fibers) vs. gastrocnemius (1,000 fibers)
14. a single brief stimulus that produces a short contraction and relaxation.
15. repeated stimuli in which the intensity of the contraction increases but returns back to full relaxation in between.
16. repeated stimuli which increase in intensity and do not return to full relaxation.
17. higher frequency stimuli which maintains nearly maximum intensity of contraction.
18. incomplete has partial relaxation.
19. latent, contraction, relaxation.
20. sensory, motor, interneuron.
21. fastest conducting (100ms), largest diameter, seen in motor efferents and muscle spindle afferents.
22. (50ms), touch and pressure mechanoreceptor axons.
23. (20ms), muscle spindle efferents.
24. (15ms), skin temperature and pain.
25. slower myelinated fibers seen in sympathetic preganglionics.
26. unmyelinated fibers seen in sympathetic postganglionics.
27. sensory receptor, sensory neuron, interneuron, motor neuron, effector organ.
28. muscle spindle receptors, golgi tendon organs, joint kinesthetic receptors.
29. located in between muscle fibers, measure length of muscle and speed of contraction.
30. the muscle spindle receptors have intrafusal fibers which are embedded within the extrafusal muscle fibers of a muscle.
31. nuclear bag fibers and nuclear chain fibers. bag fibers have nuclei in the center, contractile elements attached to extrafusal fibers (which receive motor efferents from A-gamma neurons), detect fast changes in muscle length. chain fibers have nuclei spread throughout, contractile elements attached to the bag fibers, and detect slow and steady changes in muscle length.
32. primary (Ia) sensory neurons are wrapped around the center of muscle spindle receptors, are faster conducting, and respond to change in muscle length. secondary "flower spray" sensory endings are smaller diameter and slower conducting and respond to the overall length of fiber.
33. monosynaptic spinal reflexes (rapid adjustments to prevent falls) and cerebellum controlled stretch response (to regulate muscle tone.
34. firing of gamma motor neurons causes shortening of the contractile elements within the spindle fibers, increasing their sensitivity to stretch; useful when trying to maintain balance because quick and precise feedback is needed.
35. free nerve endings located at junction between tendon and muscle.
36. force of muscle contraction / tension exerted at the tendon.
37. it can detect excess force applied to a muscle, which fires the 1b sensory fiber, which activates the inhibitory interneuron, which has an inhibitory effect on the motor neuron that innervates the muscle, causing it to relax and reduce tension.
38. dynamic response, an involuntary relaxation due to a sudden increase in muscle tension, and static response; an ongoing relaxation in response to a gradual increase in muscle tension.
39. pacinian corpuscles, ruffini corpuscles, free nerve endings.
40. movement, tension, acceleration, strain, postural changes in joint.
41. pacinian corpuscles are located within connective tissue and sense rapid pressure changes, stretch, acceleration/deceleration. ruffini corpuscles are located in synovial capsules and ligaments and sense deep rapid/sustained pressure, lateral stretch, and joint angle changes. free nerve endings are ubiquitous and sense rapid and sustained pressure.
42. quick stretch reflex, reciprocal inhibition, autogenic inhibition.
43. mediated by muscle spindle receptors, produces a quick contraction of muscle fiber in response to stretching.
44. also mediated by muscle spindle receptors, producing an inhibition in the antagonist muscles in response to stretching.
the neuromuscular junction is the site at which the motor neuron synapses with the muscle, at the motor plate. muscle contraction occurs when an action potential propagates down to the end of the axon, which causes release of acetylcholine, which migrates to the motor plate and binds to receptor channels, causing a membrane potential which propagates down the t tubules of the myofibrils, causing release of calcium from the terminal cisternae of the sarcoplasmic reticulum, which initiates the contraction of the myofilaments. relaxation occurs which calcium is sequested back into the sarcoplasmic reticulum and acetylcholine esterase breaks down the acetylcholine that was released into the NMJ.
muscle contraction can be classified in several different manners depending on frequency, intensity, and relaxation between contractions. a twitch is a single contraction and a full relaxation. within a twitch there are three stages: the latent, contraction, and relaxation phase. "treppe" is repeated contractions of increasing intensity with a return to full relaxation in between. "wave summation" is similar to treppe but without the full relaxation in between. "tetanus" is a higher frequency, maximal intensity contraction with barely any or no relaxation in between contractions.
there are several different types of axons which provide motor and sensory innervation to muscles. A-alpha, thickest and fastest conducting, seen in motor efferents and muscle spindle receptor afferents. A-beta, seen in touch and pressure mechanoreceptor afferents. A-gamma, seen in muscle spindle efferents. A-delta, seen in skin temperature and pain afferents. B fibers, seen in sympathetic preganglionics, and C fibers (unmyelinated), seen in sympathetic postganglionics.
there are three main types of proprioceptors: muscle spindles receptors, golgi tendon organs, and joint kinesthetic organs. muscle spindles are located within the muscle belly (called "extrafusal fibers") and are composed of intrafusal fibers, either "bags" or "chains", which are wrapped with a sensory nerve ending. nuclear bag fibers have contractile ends that are attached to the extrafusal fibers, nuclei in the center of the fiber, and detect fast changes in muscles length-- whereas nuclear chain fibers are attached to the nuclear bag fibers themselves and detect slow, steady chains. primary "Ia" sensory endings are wrapped around the center of spindle receptors and respond to change in muscle length; secondary "flower spray" sensory endings are slower conducting and respond to the overall length of the fiber.
spindle receptors are involved in both rapid adjustments to maintain balance as well as slower adjustments to maintain posture. the reflex they are involved in is called the "quick stretch reflex"-- extrafusal muscle causes stretching of the muscle spindle, which activates the primary or secondary nerve, which activates an interneuron which activates the motor innervation of the muscle itself-- in essence providing a balancing / feedback system for quickly contracting muscles. spindle receptors also mediate the reciprocal inhibition reflex pathway, which inhibit the antagonist muscles.
golgi tendon organ receptors are embedded within the tendon of the muscles and are involved in a complementary reflex loop- at the extremes of contraction, when tension is high in the tendon of the muscle, golgi tendon organs stimulate 1b sensory nerves, which activate the inhibitory interneurons for the muscle, causing it to relax (while simultaneously activating the antagonist muscles).
the third type of proprioceptor is the joint kinesthetic receptor, which are located within joints and detect joint movement, tension, and angle. pacinian corpuscles are located within connective tissue and sense rapid pressure changes, stretch, and acceleration of the joint motion. ruffini corpuscles are located in synovial capsules and ligaments and sense deep/rapid sustained pressure, lateral stretch, and joint angle changes. free nerve endings are found throughout and sense both rapid and sustained pressure.
questions
what are these functional units surrounded by and what do they contain?
1. skeletal muscle
2. muscle fascicle
3. muscle fiber
4. myofibril
5. sarcomere
NMJ...
6. what is a neuromuscular junction?
7. what are "motor points" and where are they generally?
8. what is the neurotransmitter that is released from axons at the NMJ?
9. what is involved in the relaxation of a muscle in the NMJ?
10. describe the process of contraction starting from release of neurotransmitter from the axon at the NMJ.
11. describe the process of muscle relaxation.
contraction types...
12. what is a "motor unit"?
13. what are examples of small and large motor units?
14. what is a muscle "twitch"?
15. what is a "treppe"?
16. what is a "wave summation"?
17. what is "tetanus"?
18. what is the difference between incomplete and complete tetanus?
19. what are the three phases to the muscle twitch?
axonal classifications...
20. what are three types of neurons?
21. describe the A-alpha classification of nerve fiber.
22. ...A-beta.
23. ...A-gamma.
24. ...A-delta.
25. ...B fibers.
26. ...C fibers.
27. what are the 5 components to a spinal cord reflex arc?
spindles...
28. what are the three types of proprioceptors?
29. where are muscle spindle receptors located? what do they measure?
30. what are intrafusal and extrafusal fibers?
31. what are the two types of intrafusal fibers and what is the difference between them?
32. what are the two types of sensory neurons from muscle spindle receptors and what is the difference between them?
33. what are the two types of responses to stretch that muscle spindle receptors are involved in?
34. describe the role of gamma motor neurons in maintaining balance.
golgi tendon organs...
35. what are golgi tendon organs?
36. what do golgi tendon organs detect?
37. describe how a golgi tendon organ can protect a muscle from damage.
38. describe the two types of stretch responses that a golgi tendon organ can be involved in.
joint kinesthetic receptors...
39. what are the three types of joint kinesthetic receptors?
40. what do joint kinesthetic receptors sense?
41. describe the different locations and functions of the different types of joint kinesthetic receptors.
proprioceptors affect on reflex muscle tone...
42. what are the three types of reflexes that proprioceptors mediate?
43. describe the quick stretch reflex.
44. describe the reciprocal inhibition reflex.
answers
1. surrounded by epimysium, contains muscle fascicles.
2. surrounded by perimysium, contains muscle fibers.
3. surrounded by endomysium, contains myofibrils.
4. surrounded by sarcoplasmic reticulum, consists of sarcomeres.
5. contains thick and thin filaments.
6. where a motor nerve synapses with a muscle fiber.
7. the actual point at which the nerve synapses- generally in the center of the muscle belly.
8. AcH.
9. breakdown of AcH by AcHesterase.
10. acetylcholine released from axon into NMJ, which bind to receptors on motor end plate and creates action potential, which propogates through the t tubules, causing calcium to be released from sarcoplasmic reticulum, which initiates the contraction of the myofilaments by binding to troponin and exposing binding sites on tropomyosin.
11. calcium is sequestered into the sarcoplasmic reticulum, acetylcholine broken down by esterase in the NMJ.
12. a nerve and all the muscle fibers it innervates.
13. extraocular muscles (20 fibers) vs. gastrocnemius (1,000 fibers)
14. a single brief stimulus that produces a short contraction and relaxation.
15. repeated stimuli in which the intensity of the contraction increases but returns back to full relaxation in between.
16. repeated stimuli which increase in intensity and do not return to full relaxation.
17. higher frequency stimuli which maintains nearly maximum intensity of contraction.
18. incomplete has partial relaxation.
19. latent, contraction, relaxation.
20. sensory, motor, interneuron.
21. fastest conducting (100ms), largest diameter, seen in motor efferents and muscle spindle afferents.
22. (50ms), touch and pressure mechanoreceptor axons.
23. (20ms), muscle spindle efferents.
24. (15ms), skin temperature and pain.
25. slower myelinated fibers seen in sympathetic preganglionics.
26. unmyelinated fibers seen in sympathetic postganglionics.
27. sensory receptor, sensory neuron, interneuron, motor neuron, effector organ.
28. muscle spindle receptors, golgi tendon organs, joint kinesthetic receptors.
29. located in between muscle fibers, measure length of muscle and speed of contraction.
30. the muscle spindle receptors have intrafusal fibers which are embedded within the extrafusal muscle fibers of a muscle.
31. nuclear bag fibers and nuclear chain fibers. bag fibers have nuclei in the center, contractile elements attached to extrafusal fibers (which receive motor efferents from A-gamma neurons), detect fast changes in muscle length. chain fibers have nuclei spread throughout, contractile elements attached to the bag fibers, and detect slow and steady changes in muscle length.
32. primary (Ia) sensory neurons are wrapped around the center of muscle spindle receptors, are faster conducting, and respond to change in muscle length. secondary "flower spray" sensory endings are smaller diameter and slower conducting and respond to the overall length of fiber.
33. monosynaptic spinal reflexes (rapid adjustments to prevent falls) and cerebellum controlled stretch response (to regulate muscle tone.
34. firing of gamma motor neurons causes shortening of the contractile elements within the spindle fibers, increasing their sensitivity to stretch; useful when trying to maintain balance because quick and precise feedback is needed.
35. free nerve endings located at junction between tendon and muscle.
36. force of muscle contraction / tension exerted at the tendon.
37. it can detect excess force applied to a muscle, which fires the 1b sensory fiber, which activates the inhibitory interneuron, which has an inhibitory effect on the motor neuron that innervates the muscle, causing it to relax and reduce tension.
38. dynamic response, an involuntary relaxation due to a sudden increase in muscle tension, and static response; an ongoing relaxation in response to a gradual increase in muscle tension.
39. pacinian corpuscles, ruffini corpuscles, free nerve endings.
40. movement, tension, acceleration, strain, postural changes in joint.
41. pacinian corpuscles are located within connective tissue and sense rapid pressure changes, stretch, acceleration/deceleration. ruffini corpuscles are located in synovial capsules and ligaments and sense deep rapid/sustained pressure, lateral stretch, and joint angle changes. free nerve endings are ubiquitous and sense rapid and sustained pressure.
42. quick stretch reflex, reciprocal inhibition, autogenic inhibition.
43. mediated by muscle spindle receptors, produces a quick contraction of muscle fiber in response to stretching.
44. also mediated by muscle spindle receptors, producing an inhibition in the antagonist muscles in response to stretching.
Saturday, April 25, 2009
biomechanics: skeletal muscle
week 2 in biomechanics covered the basics of skeletal muscle from a biomechanics perspective. skeletal muscle is the main muscle type in the body and is responsible for voluntary, gross movements, and makes up 40-50% of body weight. some muscle basics: tension produced by muscle is proportional to the amount of cross sectional muscle fibers. the strength of a muscle is defined as the tension produced from a single maximal effort, while the power produced by a muscle is the tension produced over time. muscle contractions can either be isotonic or isometric, the former being constant force with movement and the latter being varying force with no movement. within isotonic contractions, there are concentric contractions, in which the muscle gets shorter, and eccentric contractions, in which the muscle gets longer. the "line of pull" of a muscle is the primary direction in which the muscle pulls the bone.
each muscle is made of muscle fibers that are arranged in different ways according to the specific function of the muscle. parallel muscles such as the sartorius are designed for a greater range of motion / muscle shortening. fusiform muscles are similar to parallel except with a larger muscle belly, in a spindle shape, such as the biceps brachii. pennate muscles have muscle fibers oriented obliquely to the muscle tendon so as to increase the muscle's cross sectional diameter and increase strength- such as the deltoid muscles. convergent muscles such as the pectoralis major have a broad origin and a pointed origin, and varied lines of pull. circular muscles such as the sphincters and orbicularis oris have concentric muscle fibers that close over a hole when contracted.
agonists are defined as the prime muscle that produces a given movement. antagonists are the muscle that directly opposes the agonist movement- such as the biceps and triceps brachii. stabilizers are muscles that stabilize the action of the agonist-- such as the way that the rhomboids and pectoralis minor stabilize the deltoid by immobilizing its point of origin, the scapula. synergists are muscles that aid the movement of the agonist muscle.
muscles can be analyzed in terms of the type of "lever" that are schematically similar to. there are two important types of levers which produce complementary functions. a mechanical advantage lever is one in which the effort (the force applied) is far from the fulcrum (the point of rotation), which is close to the load (the object being moved). this type of lever (note that a car jack fits this description) lifts a large load a small distance for a small effort over a long distance. the other type of lever is a speed lever, in which the effort is close to the fulcrum, which is far away from the load. this type of lever allows for high speeds at the cost of high effort/tension. levers in the body can also be classified in the "class system"- first class levers have the fulcrum between the load and the effort, as in the posterior cervical muscles. second class levers are mechanical advantage levers that have the fulcrum between the effort and load and closer to the load, as in the gastrocnemius. third class levers are speed levers in which the effort is closer to the load than the fulcrum, as in the biceps.
questions
muscle introduction...
1. describe the role of skeletal muscle in the body.
2. how many skeletal muscles are there in the body and how much of the body weight do they take up?
3. a muscle's cross sectional diameter...
muscle types...
4. what are the different types of fiber arrangements in muscle and what are examples of each?
5. describe the arrangement and function of parallel muscles. what is an example of this type of muscle?
6. describe the arrangement and function of fusiform muscles. what is an example of this type of muscle?
7. describe the arrangement and function of pennate muscles. what is an example of this type of muscle?
8. describe the arrangement and function of convergent muscles. what is an example of this type of muscle?
9. describe the arrangement and function of circular muscles. what is an example of this type of muscle?
muscle contraction...
10. define muscle strength, power, and torque.
11. muscle contractions are either...
12. what is an isometric contraction?
13. what is an isotonic contraction?
14. what is the difference between a concentric and eccentric isotonic contraction?
15. what is the "line of pull" of a muscle?
16. what is an example of a muscle which has different actions because of a shifting line of pull?
17. how is line of pull related to proper muscle function?
18. what is the "angle of pull" of a muscle?
19. what are the two components to the angle of pull and what do they do?
muscle function terminology...
20. range of motion of a muscle depends on...
21. tension produced in a muscle depends on...
22. what is muscle irritability?
23. what is contractility?
24. what is extensibility?
25. what is elasticity?
muscle roles...
26. what are agonists?
27. what are antagonists? what is an example of an agonist/antagonist pair?
28. what are synergist muscles?
29. what are stabilizers? what is an example?
levers...
30. what is a fulcrum?
31. describe a mechanical advantage / power lever.
32. describe a speed lever.
33. what is a first class lever? what is an example in the body?
34. what is a second class lever? what is an example in the body?
35. what is a third class lever? what is an example in the body?
36. most levers in the body are...
answers
1. skeletal muscle is always attached to bone and is responsible for the movement of the body and all of its joints, as well as aiding in fluid and blood movement throughout the body, and providing protection and postural support.
2. over 600, 40-50% of body weight.
3. ...affects the muscle's ability to exert a force.
4. parallel, fusiform, pennate, convergent, circular.
5. muscle fibers are oriented parallel to muscle direction. designed for greater range of motion. example is sartorius.
6. similar to parallel muscles but with more of a spindle shape- larger cross sectional diameter in the middle. example is biceps brachii.
7. high cross sectional area muscle due to fibers being arranged perpendicularly to tendon. examples are extensor digitorum, rectus femoris, deltoid.
8. a muscle with a broad origin and a pointed insertion. the direction of pull can be varied. example is the pectoralis major.
9. fibers are arranged concentrically so as to form a sphincter. examples are orbicularis oris or sphincter muscles.
10. muscle strength= amount of tension a muscle can produce for a single maximal effort. muscle power= the amount of tension or contraction over a given period of time. muscle torque= muscle force causing rotation around an axis.
11. isometric or isotonic.
12. a muscle contraction in which the length of the muscle or the angle of the joint stays the same regardless of the tension.
13. a muscle contraction in which the tension in the muscle is relatively constant, producing motion in the joint or shortening / lengthening of the muscle.
14. concentric contraction is an isotonic contraction in which the muscle is being shortened, and in eccentric the muscle is being elongated.
15. the direction in which the muscle pulls when contracted.
16. when the humerus is abducted sufficiently such that the line of pull for the pectoralis major is above the glenohumeral joint, the pectoralis major can become an abductor of the humerus in addition to its primary flexion role.
17. each muscle has an optimal line of pull. an altered line of pull can cause hypertonicity and inefficiency, ultimately leading to weakness, trigger points, imbalance, etc.
18. the angle which is formed between the bone of insertion and the line of pull.
19. the verticle component (perpendicular to the bone of insertion) causes rotational movement at the join and the horizontal component causes a stabilizing force.
20. length of muscle fibers
21. total number of muscle fibers
22. muscle excitability- how sensitive or responsive the muscle is to chemical, electrical, mechanical stimuli.
23. ability of the muscle to develop tension when stimulated.
24. ability of the muscle to be stretched beyond its normal resting length.
25. ability of muscle to return to original length after stretching.
26. the prime muscle that provides the major force for a given movement.
27. muscle that produces a motion opposite to that produced by the agonist. example is biceps and triceps brachii.
28. a muscle which assists the agonist muscle.
29. muscles that support and improve the efficiency of the agonist. rhomboids and pec minor are stabilizers of the scapula when the deltoids are abducting the arm.
30. the fixed point of leverage, as in the joints of the body.
31. load is close to the fulcrum and the effort is far from the fulcrum. small effort over long distance can move a large load over small distance. (car jack)
32. load is far from the fulcrum and the effort is close to the fulcrum. large effort and fast movement.
33. a lever in which the fulcrum lies between the effort and the load, as in the posterior cervical muscles.
34. a lever in which the load lies between the fulcrum and the effort, as in the gastrocnemius. mechanical advantage levers.
35. a lever in which the effort lies between the fulcrum and the load, as in the biceps.
36. third class-- speed levers.
each muscle is made of muscle fibers that are arranged in different ways according to the specific function of the muscle. parallel muscles such as the sartorius are designed for a greater range of motion / muscle shortening. fusiform muscles are similar to parallel except with a larger muscle belly, in a spindle shape, such as the biceps brachii. pennate muscles have muscle fibers oriented obliquely to the muscle tendon so as to increase the muscle's cross sectional diameter and increase strength- such as the deltoid muscles. convergent muscles such as the pectoralis major have a broad origin and a pointed origin, and varied lines of pull. circular muscles such as the sphincters and orbicularis oris have concentric muscle fibers that close over a hole when contracted.
agonists are defined as the prime muscle that produces a given movement. antagonists are the muscle that directly opposes the agonist movement- such as the biceps and triceps brachii. stabilizers are muscles that stabilize the action of the agonist-- such as the way that the rhomboids and pectoralis minor stabilize the deltoid by immobilizing its point of origin, the scapula. synergists are muscles that aid the movement of the agonist muscle.
muscles can be analyzed in terms of the type of "lever" that are schematically similar to. there are two important types of levers which produce complementary functions. a mechanical advantage lever is one in which the effort (the force applied) is far from the fulcrum (the point of rotation), which is close to the load (the object being moved). this type of lever (note that a car jack fits this description) lifts a large load a small distance for a small effort over a long distance. the other type of lever is a speed lever, in which the effort is close to the fulcrum, which is far away from the load. this type of lever allows for high speeds at the cost of high effort/tension. levers in the body can also be classified in the "class system"- first class levers have the fulcrum between the load and the effort, as in the posterior cervical muscles. second class levers are mechanical advantage levers that have the fulcrum between the effort and load and closer to the load, as in the gastrocnemius. third class levers are speed levers in which the effort is closer to the load than the fulcrum, as in the biceps.
questions
muscle introduction...
1. describe the role of skeletal muscle in the body.
2. how many skeletal muscles are there in the body and how much of the body weight do they take up?
3. a muscle's cross sectional diameter...
muscle types...
4. what are the different types of fiber arrangements in muscle and what are examples of each?
5. describe the arrangement and function of parallel muscles. what is an example of this type of muscle?
6. describe the arrangement and function of fusiform muscles. what is an example of this type of muscle?
7. describe the arrangement and function of pennate muscles. what is an example of this type of muscle?
8. describe the arrangement and function of convergent muscles. what is an example of this type of muscle?
9. describe the arrangement and function of circular muscles. what is an example of this type of muscle?
muscle contraction...
10. define muscle strength, power, and torque.
11. muscle contractions are either...
12. what is an isometric contraction?
13. what is an isotonic contraction?
14. what is the difference between a concentric and eccentric isotonic contraction?
15. what is the "line of pull" of a muscle?
16. what is an example of a muscle which has different actions because of a shifting line of pull?
17. how is line of pull related to proper muscle function?
18. what is the "angle of pull" of a muscle?
19. what are the two components to the angle of pull and what do they do?
muscle function terminology...
20. range of motion of a muscle depends on...
21. tension produced in a muscle depends on...
22. what is muscle irritability?
23. what is contractility?
24. what is extensibility?
25. what is elasticity?
muscle roles...
26. what are agonists?
27. what are antagonists? what is an example of an agonist/antagonist pair?
28. what are synergist muscles?
29. what are stabilizers? what is an example?
levers...
30. what is a fulcrum?
31. describe a mechanical advantage / power lever.
32. describe a speed lever.
33. what is a first class lever? what is an example in the body?
34. what is a second class lever? what is an example in the body?
35. what is a third class lever? what is an example in the body?
36. most levers in the body are...
answers
1. skeletal muscle is always attached to bone and is responsible for the movement of the body and all of its joints, as well as aiding in fluid and blood movement throughout the body, and providing protection and postural support.
2. over 600, 40-50% of body weight.
3. ...affects the muscle's ability to exert a force.
4. parallel, fusiform, pennate, convergent, circular.
5. muscle fibers are oriented parallel to muscle direction. designed for greater range of motion. example is sartorius.
6. similar to parallel muscles but with more of a spindle shape- larger cross sectional diameter in the middle. example is biceps brachii.
7. high cross sectional area muscle due to fibers being arranged perpendicularly to tendon. examples are extensor digitorum, rectus femoris, deltoid.
8. a muscle with a broad origin and a pointed insertion. the direction of pull can be varied. example is the pectoralis major.
9. fibers are arranged concentrically so as to form a sphincter. examples are orbicularis oris or sphincter muscles.
10. muscle strength= amount of tension a muscle can produce for a single maximal effort. muscle power= the amount of tension or contraction over a given period of time. muscle torque= muscle force causing rotation around an axis.
11. isometric or isotonic.
12. a muscle contraction in which the length of the muscle or the angle of the joint stays the same regardless of the tension.
13. a muscle contraction in which the tension in the muscle is relatively constant, producing motion in the joint or shortening / lengthening of the muscle.
14. concentric contraction is an isotonic contraction in which the muscle is being shortened, and in eccentric the muscle is being elongated.
15. the direction in which the muscle pulls when contracted.
16. when the humerus is abducted sufficiently such that the line of pull for the pectoralis major is above the glenohumeral joint, the pectoralis major can become an abductor of the humerus in addition to its primary flexion role.
17. each muscle has an optimal line of pull. an altered line of pull can cause hypertonicity and inefficiency, ultimately leading to weakness, trigger points, imbalance, etc.
18. the angle which is formed between the bone of insertion and the line of pull.
19. the verticle component (perpendicular to the bone of insertion) causes rotational movement at the join and the horizontal component causes a stabilizing force.
20. length of muscle fibers
21. total number of muscle fibers
22. muscle excitability- how sensitive or responsive the muscle is to chemical, electrical, mechanical stimuli.
23. ability of the muscle to develop tension when stimulated.
24. ability of the muscle to be stretched beyond its normal resting length.
25. ability of muscle to return to original length after stretching.
26. the prime muscle that provides the major force for a given movement.
27. muscle that produces a motion opposite to that produced by the agonist. example is biceps and triceps brachii.
28. a muscle which assists the agonist muscle.
29. muscles that support and improve the efficiency of the agonist. rhomboids and pec minor are stabilizers of the scapula when the deltoids are abducting the arm.
30. the fixed point of leverage, as in the joints of the body.
31. load is close to the fulcrum and the effort is far from the fulcrum. small effort over long distance can move a large load over small distance. (car jack)
32. load is far from the fulcrum and the effort is close to the fulcrum. large effort and fast movement.
33. a lever in which the fulcrum lies between the effort and the load, as in the posterior cervical muscles.
34. a lever in which the load lies between the fulcrum and the effort, as in the gastrocnemius. mechanical advantage levers.
35. a lever in which the effort lies between the fulcrum and the load, as in the biceps.
36. third class-- speed levers.
Wednesday, April 15, 2009
biomechanics: introduction and joints
the first lecture in biomechanics introduced the core concepts we will be using to explore the body in this class. biomechanics is the study of how the rules of physics can be applied to the human body. some terminology: osteokinematics is the study of gross bone movement whereas arthrokinematics is the study of how the bones shift in the joint during movement. the three cardinal planes of motion are sagittal, coronal/frontal, and transverse and the three axes of rotation are the sagittal, longitudinal, and frontal axes. all movement can be described in terms of translation and rotation according to the frame of reference from these planes and rotational axes.
there are many different types of joints in the body, which are all specialized according to the type of movement they permit. joints can be classified by how much movement they permit: synarthrodial joints such as the fibrous joints between skull bones or those that anchor the teeth are very tight and do not permit much movement. amphiarthrodial joints permit "some" movement, as in the syndesmosis joints (interosseus membrane) or synchondrosis joints (costosternal joint or epiphyseal plate).
the most mobile joints are called diarthrodial, of which synovial joints are the prime example- these joints are characterized by the separation of the two bones by a fluid filled cavity. there are six types of synovial joints in the body: gliding joints, which only permit a sliding motion as in the metacarpal joint or facet joints of the vertebrae. hinge joints, which permit uniaxial movement as in the humerus and ulna. pivot joints, which permit rotation of one bone along an axis parallel to the other bone such as the atlas/axis. ellipsoid or condyloid joints have an oval surface / depression which allows for biaxial movement, as in the radiocarpal joint. saddle joints are only seen in the thumbs, where each articular surface is saddle shaped and allows for biaxial movement. finally, ball and socket joints allow for multi-axial movement and are seen in the humrus/shoulder joint and the femur/hip joint.
questions
therapeutic order and biomechanics intro...
1. what is meant by "therapeutic order" in naturopathy?
2. how does biomechanics fit into the therapeutic order?
3. how are first order and second order interventions defined?
4. what is "somatovisceral influence" and what is an example?
5. what is "viscerosomatic influence" and what is an example?
kinesiology and kinematics...
6. define kinesiology, kinematics, and biomechanics.
7. what is the difference between osteokinematics and arthrokinematics?
8. what are two types of kinematic motion?
9. what are the two types of translation motion?
10. what is the difference between active and passive motion?
11. what is the difference between the "anatomical" and "reference" positions?
planes and axes...
12. what are the cardinal planes of motion?
13. what are the three axes of motion?
14. describe flexion/extension in terms of axes and planes of motion.
15. describe abduction/adduction in terms of axes and planes of motion.
16. describe rotation in terms of axes and planes of motion.
osteokinematics...
17. what are 2 types of motion that can occur at joints between bones and what are examples of each?
18. describe flexion and extension in terms of their effect on the angle between bones.
19. describe the ab- and adduction motion.
20. describe the circumduction motion.
21. describe the supination/pronation motion.
22. describe the inversion/eversion motion.
23. describe plantar and dorsiflexion.
24. describe the opposition/reposition motion of the thumb.
joints...
25. what are 3 functional classifications of joints in the body?
26. what are 3 structural classifications of joints?
27. describe suture joints.
28. describe gomphosis joints.
29. describe syndesmosis joints.
30. describe cartilaginous joints.
31. depending on the length of collagen fibers, cartilaginous joints may be...
32. what are two types of cartilaginous joints?
33. what is a synchondrosis joint? what are some examples?
34. what is a symphysis joint? what are some examples?
synovial joints...
35. describe the layout of a synovial joint.
36. what is synovial fluid and what does it do?
37. what are the six types of synovial joints?
38. describe the gliding synovial joint.
39. describe the hinge synovial joint.
40. describe the pivot joint.
41. describe the condyoid joint.
42. describe the saddle joint.
43. describe the ball and socket joint.
answers
1. the "therapeutic order" is the framework of therapeutic actions of increasing severity: establishing the conditions for health (diagnosis), stimulating the vis medicatrix naturae, addressing weakened systems or organs, correcting structural integrity, addressing pathology with natural methods, addressing pathology with synthetic methods, and finally suppressing or removing pathology.
2. biomechanics deals with the "correcting structural integrity" portion of the therapeutic order.
3. in general first order intervention deals with purely structural dysfunction whereas second order intervention deals with structural dysfunction that is the result of visceral dysfunction.
4. somatovisceral influence is the musculoskeletal system influencing the visceral organs; such as bad posture cutting off blood supply to the organs.
5. the internal organs causing musculoskeletal dysfunction, such as stomach problems causing back pain.
6. kinesiology is the study of motion or movement of the human body; biomechanics is the application of the laws of physics to the movement of the body; kinematics is the study of motion of the body without regard to the forces that intrinsically produce those motions (as in muscles).
7. osteokinematics deals with gross movements of bones in the cardinal planes while arthrokinematics deals with the movements that occur within the joints between the bones.
8. translation and rotation.
9. rectilinear and curvilinear.
10. active motion is produced by the muscles and passive motion is produced by external forces acted upon the body.
11. anatomical has palms facing forward and reference have hands faced inwards.
12. sagittal, frontal, transverse.
13. frontal (X), sagittal (Z), longitudinal (Y).
14. flexion/extension is movement within the sagittal plane along the frontal axis.
15. movement within the frontal plane along the sagittal axis.
16. movement within the transverse plane along the longitudinal axis.
17. linear motion (metacarpals and facet joints) and angular motion (virtually all other joints)
18. flexion in general decreases the angle between two bones and extension does the opposite.
19. angular motion in the frontal plane along the sagittal axis.
20. circular motion without rotation: a combination of flexion/extension and adduction/abduction.
21. supination is rotation of the palm upwards and pronation is rotation downwards.
22. inversion is the bending of the foot medially such that the ankle points out and the weight is on the lateral edge of the foot, and eversion is the opposite.
23. plantar flexion is extension of the foot (pointing the toes) and dorsiflexion is flexion of the foot (pulling back the toes)
24. opposition is the movement of the thumb towards the other fingers and reposition is the opposite.
25. synarthrodial, amphiarthrodial, diarthrodial, indicating joints with little to no movement, some movement, and ample movement, respectively.
26. fibrous, cartilaginous, synovial, roughly corresponding to synarthrodial, amphiarthrodial, and diarthrodial.
27. suture joints are short fibrous connective tissue between the bones of the skull that blends into the periosteum.
28. gomphosis joints are the peg and socket shaped fibrous joints that are seen in the teeth- in this case the joint is made of periodontal ligament.
29. syndesmosis joints are bands or cords of tissue that interconnect two bones, such as the interossues membrane between the tibia and the fibula.
30. bones joint by cartilage; no joint cavity.
31. synarthrodial or amphiarthrodial.
32. synchondrosis or symphysis.
33. bones connected by hyaline cartilage, such as the epiphyseal plate or costosternal joint.
34. articular surfaces of bones covered with cartilage for shock absorption; intervertebral joints or pubic symphysis.
35. two bones separated by a fluid filled cavity which is connected by ligaments of dense connective tissue.
36. largely hyaluronic acid, fills all free space within the synovial joint capsule. reduces friction and nourishes articular cartilage.
37. gliding, hinge, pivot, condyoid, saddle, ball and socket.
38. flat articular surfaces allows for only gliding or slipping movements, such as in the facet joints in vertebrae or intercarpal joints.
39. a convex surface of bone fitting into a concave surface which allows for uni-axial movement, such as the ulna and humerus joint.
40. a joint that joins two bones so as to allow rotation of one bone on an axis parallel to the other bone, such as the axis/atlas joint or the proximal radioulnar joint.
41. an oval articular surface of one bone fits into an oval depression in another which allows for all angular motions, as in the wrist or metacarpophalangeal joint. also called ellipsoid joint.
42. joint in which articular surface of each bone is shaped like a saddle, allowing for biaxial movement. only seen in the thumb.
43. a spherical or hemispherical bone fitting into a socket of another, allowing for multiaxial movement- such as the humerus and the glenoid cavity.
there are many different types of joints in the body, which are all specialized according to the type of movement they permit. joints can be classified by how much movement they permit: synarthrodial joints such as the fibrous joints between skull bones or those that anchor the teeth are very tight and do not permit much movement. amphiarthrodial joints permit "some" movement, as in the syndesmosis joints (interosseus membrane) or synchondrosis joints (costosternal joint or epiphyseal plate).
the most mobile joints are called diarthrodial, of which synovial joints are the prime example- these joints are characterized by the separation of the two bones by a fluid filled cavity. there are six types of synovial joints in the body: gliding joints, which only permit a sliding motion as in the metacarpal joint or facet joints of the vertebrae. hinge joints, which permit uniaxial movement as in the humerus and ulna. pivot joints, which permit rotation of one bone along an axis parallel to the other bone such as the atlas/axis. ellipsoid or condyloid joints have an oval surface / depression which allows for biaxial movement, as in the radiocarpal joint. saddle joints are only seen in the thumbs, where each articular surface is saddle shaped and allows for biaxial movement. finally, ball and socket joints allow for multi-axial movement and are seen in the humrus/shoulder joint and the femur/hip joint.
questions
therapeutic order and biomechanics intro...
1. what is meant by "therapeutic order" in naturopathy?
2. how does biomechanics fit into the therapeutic order?
3. how are first order and second order interventions defined?
4. what is "somatovisceral influence" and what is an example?
5. what is "viscerosomatic influence" and what is an example?
kinesiology and kinematics...
6. define kinesiology, kinematics, and biomechanics.
7. what is the difference between osteokinematics and arthrokinematics?
8. what are two types of kinematic motion?
9. what are the two types of translation motion?
10. what is the difference between active and passive motion?
11. what is the difference between the "anatomical" and "reference" positions?
planes and axes...
12. what are the cardinal planes of motion?
13. what are the three axes of motion?
14. describe flexion/extension in terms of axes and planes of motion.
15. describe abduction/adduction in terms of axes and planes of motion.
16. describe rotation in terms of axes and planes of motion.
osteokinematics...
17. what are 2 types of motion that can occur at joints between bones and what are examples of each?
18. describe flexion and extension in terms of their effect on the angle between bones.
19. describe the ab- and adduction motion.
20. describe the circumduction motion.
21. describe the supination/pronation motion.
22. describe the inversion/eversion motion.
23. describe plantar and dorsiflexion.
24. describe the opposition/reposition motion of the thumb.
joints...
25. what are 3 functional classifications of joints in the body?
26. what are 3 structural classifications of joints?
27. describe suture joints.
28. describe gomphosis joints.
29. describe syndesmosis joints.
30. describe cartilaginous joints.
31. depending on the length of collagen fibers, cartilaginous joints may be...
32. what are two types of cartilaginous joints?
33. what is a synchondrosis joint? what are some examples?
34. what is a symphysis joint? what are some examples?
synovial joints...
35. describe the layout of a synovial joint.
36. what is synovial fluid and what does it do?
37. what are the six types of synovial joints?
38. describe the gliding synovial joint.
39. describe the hinge synovial joint.
40. describe the pivot joint.
41. describe the condyoid joint.
42. describe the saddle joint.
43. describe the ball and socket joint.
answers
1. the "therapeutic order" is the framework of therapeutic actions of increasing severity: establishing the conditions for health (diagnosis), stimulating the vis medicatrix naturae, addressing weakened systems or organs, correcting structural integrity, addressing pathology with natural methods, addressing pathology with synthetic methods, and finally suppressing or removing pathology.
2. biomechanics deals with the "correcting structural integrity" portion of the therapeutic order.
3. in general first order intervention deals with purely structural dysfunction whereas second order intervention deals with structural dysfunction that is the result of visceral dysfunction.
4. somatovisceral influence is the musculoskeletal system influencing the visceral organs; such as bad posture cutting off blood supply to the organs.
5. the internal organs causing musculoskeletal dysfunction, such as stomach problems causing back pain.
6. kinesiology is the study of motion or movement of the human body; biomechanics is the application of the laws of physics to the movement of the body; kinematics is the study of motion of the body without regard to the forces that intrinsically produce those motions (as in muscles).
7. osteokinematics deals with gross movements of bones in the cardinal planes while arthrokinematics deals with the movements that occur within the joints between the bones.
8. translation and rotation.
9. rectilinear and curvilinear.
10. active motion is produced by the muscles and passive motion is produced by external forces acted upon the body.
11. anatomical has palms facing forward and reference have hands faced inwards.
12. sagittal, frontal, transverse.
13. frontal (X), sagittal (Z), longitudinal (Y).
14. flexion/extension is movement within the sagittal plane along the frontal axis.
15. movement within the frontal plane along the sagittal axis.
16. movement within the transverse plane along the longitudinal axis.
17. linear motion (metacarpals and facet joints) and angular motion (virtually all other joints)
18. flexion in general decreases the angle between two bones and extension does the opposite.
19. angular motion in the frontal plane along the sagittal axis.
20. circular motion without rotation: a combination of flexion/extension and adduction/abduction.
21. supination is rotation of the palm upwards and pronation is rotation downwards.
22. inversion is the bending of the foot medially such that the ankle points out and the weight is on the lateral edge of the foot, and eversion is the opposite.
23. plantar flexion is extension of the foot (pointing the toes) and dorsiflexion is flexion of the foot (pulling back the toes)
24. opposition is the movement of the thumb towards the other fingers and reposition is the opposite.
25. synarthrodial, amphiarthrodial, diarthrodial, indicating joints with little to no movement, some movement, and ample movement, respectively.
26. fibrous, cartilaginous, synovial, roughly corresponding to synarthrodial, amphiarthrodial, and diarthrodial.
27. suture joints are short fibrous connective tissue between the bones of the skull that blends into the periosteum.
28. gomphosis joints are the peg and socket shaped fibrous joints that are seen in the teeth- in this case the joint is made of periodontal ligament.
29. syndesmosis joints are bands or cords of tissue that interconnect two bones, such as the interossues membrane between the tibia and the fibula.
30. bones joint by cartilage; no joint cavity.
31. synarthrodial or amphiarthrodial.
32. synchondrosis or symphysis.
33. bones connected by hyaline cartilage, such as the epiphyseal plate or costosternal joint.
34. articular surfaces of bones covered with cartilage for shock absorption; intervertebral joints or pubic symphysis.
35. two bones separated by a fluid filled cavity which is connected by ligaments of dense connective tissue.
36. largely hyaluronic acid, fills all free space within the synovial joint capsule. reduces friction and nourishes articular cartilage.
37. gliding, hinge, pivot, condyoid, saddle, ball and socket.
38. flat articular surfaces allows for only gliding or slipping movements, such as in the facet joints in vertebrae or intercarpal joints.
39. a convex surface of bone fitting into a concave surface which allows for uni-axial movement, such as the ulna and humerus joint.
40. a joint that joins two bones so as to allow rotation of one bone on an axis parallel to the other bone, such as the axis/atlas joint or the proximal radioulnar joint.
41. an oval articular surface of one bone fits into an oval depression in another which allows for all angular motions, as in the wrist or metacarpophalangeal joint. also called ellipsoid joint.
42. joint in which articular surface of each bone is shaped like a saddle, allowing for biaxial movement. only seen in the thumb.
43. a spherical or hemispherical bone fitting into a socket of another, allowing for multiaxial movement- such as the humerus and the glenoid cavity.
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