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371 Cards in this Set
- Front
- Back
what four joints are included in the shoulder complex?
|
(1) sternoclavicular
(2) acromioclavicular (3) glenohumeral (4) scapulothoracic |
|
the scapular plane is __-__º anterior to the frontal plane
|
30-40
|
|
another name for arm elevation in the scapular plane
|
scaption
|
|
this movement allows the naturally retroverted humeral head to fit more directly into the glenoid
|
scaption
|
|
during scaption, what muscle fibers become oriented for the best mechanical advantage?
|
supraspinatus
|
|
what 6 motions occur at the scapulothoracic joint?
|
(1) upward/downward rotation
(2) anterior/posterior tilting (3) internal/external rotation (4) abduction and adduction (5) elevation/depression (6) winging (ABNORMAL) |
|
what joint do upward and downward rotation occur at?
|
AC
|
|
movement of the scapula in which the inferior angle moves laterally and the glenoid fossa rotates cranially; aka lateral rotation
|
upward rotation
|
|
movement of the scapula in which the inferior angle moves medially and the glenoid rotates caudally; aka medial rotation
|
downward rotation
|
|
a movement in which the scapula translates along the ribcage in a cranial direction
|
elevation
|
|
a movement in which the scapula translates along the ribcage in a caudal direction
|
depression
|
|
the scapula translates medially along the rib cage toward the vertebral column; this movement often occurs with external rotation
|
adduction
|
|
what other movement does scapular adduction usually occur with?
|
external rotation
|
|
the scapula translates laterally along the rib cage away from the vertebral column; this movement often occurs with internal rotation
|
abduction
|
|
what other movement does scapular abduction usually occur with?
|
internal rotation
|
|
what is the axis for internal and external rotation of the scapula?
|
vertical
|
|
these motions occur about an axis parallel to the scapular spine at the AC joint
|
anterior/posterior tilt
|
|
movement in which the coracoid moves anteriorly and caudally while inferior angle moves posteriorly and cranially
|
anterior tilt
|
|
movement in which the coracoid moves posteriorly and cranially while the inferior angle moves anterior and caudally
|
posterior tilt
|
|
rotation of the scapula about a vertical axis at the AC joint, in which the lateral border of the scapula moves anteromedialy and the vertebral border moves posterolaterally so that the costal surface faces more towrad the midline of the body
|
internal rotation
|
|
movement of the scapula in which the lateral border of the scapula moves posterolaterally and the vertebral border moves anteromedially so the costal surface faces more away from the midline of the body
|
external rotation
|
|
abnormal movement of the scapula about a vertical axis; in which the vertebral border moves in a posterior and lateral direction away from the ribcage
|
winging
|
|
winging occurs via excess of what scapular motion?
|
internal rotation
|
|
what type of joint is the sternoclavicular joint?
|
saddle
|
|
this joint is the medial end of the clavicle corresponding with the sternum
|
sternoclavicular joint
|
|
is the clavicle convex or concave along the longitudinal axis?
|
convex
|
|
is the clavicle convex or concave along the transverse axis?
|
concave
|
|
this structure at the sternoclavicular joint attaches to the clavicle, costocartilage, and 1st rib, and stabilizes and increases the joint surface area while also absorbing force
|
articular disc
|
|
what three structures does the articular disc of the sternoclavicular joint attach to?
|
(1) clavicle
(2) costocartilage (3) 1st rib |
|
this ligament of the SC joint runs from the clavicle to the first rib
|
costoclavicular
|
|
these two ligaments of the SC joint run from the clavicle to the manubrium of the sternum
|
anterior and posterior sternoclavicular
|
|
this ligament of the SC joint joins the clavicular heads
|
interclavicular
|
|
what three movements cause the costoclavicular ligament to be taut?
|
(1) elevation
(2) protraction (3) retraction |
|
what movements do the anterior and posterior sternoclavicular ligaments prevent?
|
anterior and posterior dislocation
|
|
the interclavicular ligament provides stability to the __ aspect of the SC joint
|
superior
|
|
during arm elevation, the clavicle at the SC joint does what three motions?
|
(1) rotates posteriorly along a long axis
(2) retracts (3) elevates |
|
this movement occurs when the lateral or distal end of the clavicle moves posterior
|
retraction
|
|
how many degrees of elevation occurs at the SC joint?
|
45º
|
|
how many degrees of depression occurs at the SC joint?
|
10º
|
|
how many degrees of protraction occurs at the SC joint?
|
15-30º
|
|
how many degrees of retraction occurs at the SC joint?
|
15-30º
|
|
how many degrees of rotation occurs at the SC joint?
|
40-50º
|
|
what is the axis for clavicular elevation and depression?
|
anterior-posterior
|
|
what is the axis for clavicular protraction and retraction?
|
vertical
|
|
what is the axis for rotation of the clavicle?
|
longitudinal
|
|
for protraction and retraction at the SC joint, a __ clavicle is articulating on a __ sternum
|
concave, convex
|
|
for elevation and depression at the SC joint, a __ clavicle is articulating on the __ sternum
|
convex, concave
|
|
what three motions are occurring when the arm is elevating from 0-120º?
|
(1) flexion
(2) abduction (3) scaption |
|
what movement contributes the most during arm elevation at the SC joint?
|
posterior axial rotation
|
|
what is the predominate motion that occurs at the SC joint during arm movement?
|
posterior axial rotation of the clavicle
|
|
clavicular retraction occurs greatest with what humeral movement?
|
abduction
|
|
what is the order of clavicular retraction movement?
|
humeral abduction>scapular plane abduction>flexion
|
|
clavicular elevation occurs greatest with what motion?
|
abduction
|
|
during clavicular posterior axial rotation, what two movements does the scapula do?
|
upward rotation and posterior tilt
|
|
during clavicular elevation, what two movements does the scapula do?
|
upward rotation and anterior tilt
|
|
the clavicle is retracted approximately __º from the frontal plane in normal alignment
|
20
|
|
this joint is the articulation of the acromion process with the lateral end of the clavicle
|
acromoclavicular joint
|
|
what three things provide stability to the acromioclavicular joint?
|
(1) capsule
(2) acromioclavicular ligament (3) coracoacromial ligaments |
|
this ligament runs from the acromion to the distal end of the clavicle; both superior and inferior
|
acromioclavicular
|
|
what does the acromioclavicular ligament prevent?
|
separation of the clavicle and acromion
|
|
these ligaments run from the inferior surface of the clavicle to the coronoid process (do not cross the joint)
|
coracoclavicular (trapezoid and conoid)
|
|
what three movements occur at the AC joint (movement of the scapula relative to the clavicle)
|
(1) upward/downward rotation
(2) internal/external rotation (3) tilting/tipping |
|
these motions at the AC joint occur about an axis oriented in an anterior posterior direction, perpendicular to the scapular plane
|
upward and downward rotation
|
|
these movements at the AC joint occur at a vertical axis from the scapula to the clavicle
|
internal and external rotation
|
|
in this movement at the AC joint, the medial border of the scapula pivots away fro the thorax and the glenoid will turn more anterior
|
internal rotation
|
|
in this movement at the AC joint, the medial border of the scapla moves toward the posterior thorax and the glenoid faces laterally
|
external rotation
|
|
what is the axis for anterior and posterior tipping at the AC joint?
|
medial to lateral
|
|
at the AC joint during arm elevation, what seems to be the predominate motion of the scapula relative to the clavicle?
|
posterior tilting (19º)
|
|
what is the progression of AC joint motion during arm elevation?
|
posterior tilt>upward rotation>internal rotation
|
|
which AC joint ligament's tautness causes the clavicle to be pulled into posterior axial rotation, allowing further upward rotation of the scapula?
|
coracoclavicular
|
|
this joint is not a true joint, and movements that occur here are a result of movements at the SC and AC joints
|
scapulothoracic joint
|
|
what is the ratio of scapulohumeral rhythm?
|
2:1
|
|
this phase of the scapulohumeral rhythm describes the initial scapular motion during arm elevation
|
setting phase
|
|
what is the degree of motion in the setting phase of abduction?
|
30º
|
|
what is the degree of motion in the setting phase of flexion?
|
60º
|
|
what three things are important to consider with scapular upward rotation?
|
(1) glenoid position
(2) length-tension relationship of the deltoid and supraspinatus (3) subacromial space volume |
|
what two motions does the scapula do as the arm is elevating?
|
upward rotation and posterior tilt
|
|
during humeral abduction, the scapula appears to do what motion?
|
external rotation
|
|
during humeral flexion, what does the scapula do?
|
it may internally rotate but by end range slight external rotation should be achieved
|
|
this motion at the scapulothoracic joint is primarily achieved from posterior axial rotation of the clavicle at the SC joint and upward rotation of the scapula relative to the clavicle at the AC joint
|
upward rotation
|
|
this motion at the scapulothoracic joint is primarily from posterior tilt of the scapula relative to the clavicle at the AC joint
|
posterior tlt
|
|
this motion at the scapulothoracic joint is from clavicular retraction at the SC joint and external rotation at the AC joint (scapula relative to the clavicle)
|
external rotation
|
|
the scapula upwardly rotates __-__º with full arm elevation
|
50-60º
|
|
at end range of arm elevation, the acromion should be level with what vertebrae?
|
C6-C7
|
|
the scapula remains approximately __ inches from the spine during motion
|
3
|
|
at the end range of shoulder flexion, the scapular orientation should be __-__º anterior to the frontal plane
|
10-20
|
|
at the end range of shoulder flexion, the scapular orientation should be __-__ posterior tilt
|
5-10
|
|
normal scapular posture is about __º of anterior tilt
|
9
|
|
what vertebrae does the scapula rest between?
|
T2-T7
|
|
a forward head and rounded shoulder causes greater range of what three movements during shoulder flexion?
|
(1) internal rotation
(2) anterior tilt (3) upward rotation |
|
in what three directions is the humeral head directed at the glenohumeral joint?
|
(1) medial
(2) posterior (3) tilted upward |
|
in what two directions is the glenoid fossa directed at rest?
|
(1) lateral
(2) upward at a 5º tilt |
|
the lack of what scapular motion can cause instability at the glenohumeral joint?
|
upward rotation
|
|
elevation of the arm pulls what part of the capsule of the GH joint taut?
|
inferior
|
|
what is the closed pack position of the GH joint?
|
maximum abduction with lateral rotation
|
|
what part of the GH capsule is tensed with full internal rotation?
|
posterior
|
|
what part of the GH capsule is tensed with full external rotation?
|
anterior
|
|
what is the normal capsular pattern of restriction at the glenohumeral joint (what motions are restricted and in what order)?
|
external rotation limited>abduction>internal rotation>/= flexion
|
|
what GH ligament is taut with full adduction?
|
superior
|
|
what GH joint ligament is taut with external rotation?
|
middle
|
|
what GH joint ligament is taut with abduction?
|
inferior
|
|
what part of the inferior GH ligament is taut with external rotation?
|
anterior band
|
|
what part of the inferior GH ligament is taut with internal rotation?
|
posterior band
|
|
which GH ligament is a main stabilizer of the shoulder?
|
inferior band
|
|
this ligament runs from the coracoid process to the greater tubercle of the humerus
|
coracohumeral ligament
|
|
what four motions cause the coracohumeral ligament to become taut?
|
(1) lateral rotation
(2) flexion (3) extension (4) adduction |
|
what two things does the coracohumeral ligament restrict?
|
(1) posterior glide
(2) inferior displacement |
|
this ligament runs from the coracoid to the acromial process and prevents superior dislocation and may provide protectio to the subdeltoid bursae and supraspinatus tendon
|
coracoacromial ligament
|
|
what are the four static factors that contribute to glenohumeral stability?
|
(1) capsule, ligaments, and labrum
(2) negative intraarticular pressure (3) joint geometry-glenoid tilted 5º (4) rotator cuff muscle bulk and stiffness |
|
what is the dynamic factor that contributes to GH joint stability?
|
rotator cuff muscle contraction (increased compression and ligaments are tightened with motion)
|
|
how many degrees of flexion occur at the GH joint?
|
120º
|
|
how many degrees of extension occur at the GH joint?
|
55º
|
|
how many degrees of abduction occur at the GH joint?
|
120º
|
|
how many degrees of horizontal adduction occur at the GH joint?
|
45º
|
|
how many degrees of internal rotation with the arm abducted occur at the GH joint?
|
70º
|
|
how many degrees of external rotation with the arm abducted occur at the GH joint?
|
90º
|
|
how many degrees of external rotation with the arm at the side occur at the GH joint?
|
70º
|
|
what direction are the roll and slide for GH joint abduction?
|
superior roll, inferior glide
|
|
what can a lack of inferior glide during GH joint abduction cause?
|
impingement of the structures in the subacromial space
|
|
during external rotation at the GH joint with the arm at the side, what are the directions of the roll and glide?
|
posterior roll, anterior glide
|
|
during internal rotation at the GH joint with the arm at the side, what are the directions of the roll and glide?
|
anterior roll, posterior glide
|
|
spinning of the humeral head in the glenoid occurs when the axis of motion is __ to the joint surface
|
perpendicular
|
|
in what two instances does spinning of the humeral head on the glenoid occur?
|
(1) humeral flexion
(2) humeral IR/ER with the arm at 90º abduction |
|
in what two instances does the roll and glide occur in opposite ways at the GH joint?
|
(1) humeral abduction
(2) humeral IR/ER with the arm at the side |
|
to increase humeral external rotation with the arm at the side, what type of mobilization would you want to do?
|
anterior glide
|
|
what is the weakest region of the GH joint?
|
inferior
|
|
in what region/direction would you most easily sublux the humeral head?
|
anterior/inferior
|
|
what is often an indication of insufficient upward rotation of the scapula during arm elevation?
|
the inferior angle of the scapula does not reach the midaxillary line
|
|
what does it mean when there is greater flexion with the arm in medial rotation (as compared to the other arm)?
|
the GH joint has developed greater flexibility to compensate for a lack of scapular upward rotation
|
|
what are the five axioscapular muscles (from scapula to thorax)?
|
(1) serratus anterior
(2) trapezius (3) rhomboids (4) levator scapulae (5) pectoralis minor |
|
what are the 6 scapulohumeral muscles?
|
(1) deltoid
(2) supraspinatus (3) infraspinatus (4) subscapularis (5) teres major (6) teres minor |
|
what are the two axiohumeral muscles (from thorax to humerus)?
|
(1) latissimus dorsi
(2) pectoralis major |
|
this muscle's capability for scapular upward rotation and posterior tilt is the best of all the scapular muscles
|
serratus anterior
|
|
this muscle pulls the scapula forward on the thorax, and can externally rotate the scapula; also stabilizes it against the ribs
|
serratus anterior
|
|
how many divisions are there of the serratus anterior muscle?
|
3 (upper, middle, lower)
|
|
what division of the serratus anterior muscle is responsible for anchoring the scapula on the thorax and can ER and provide a slight UR force?
|
upper
|
|
which portion of the serratus anterior has moderate ER and UR capability?
|
middle
|
|
which portion of the serratus anterior stabilizes and moves the scpula; has 2x the UR moment arm vs the other muscles, and is also the best moment arm for posterior tilt?
|
lower
|
|
what muscle retracts and elevates the clavicle by acting at the SC joint?
|
upper trap
|
|
what two motions does the upper trap do at the SC joint?
|
retraction and elevation of the clavicle
|
|
both the middle and the lower trapezius act at what joint?
|
AC joint
|
|
what two motions does the middle trapezius do?
|
scapular adduction and external rotation
|
|
what four motions does the lower trapezius do?
|
(1) external rotation (2x ability of middle)
(2) upward rotation (3) minimal posterior tilt (4) scapular depression |
|
what are the two actions that the trapezius has on the cervical spine?
|
(1) extension
(2) rotation of vertebrae to contralateral side |
|
what two muscles form the force couple for scapular upward rotation?
|
trapezius and serratus anterior
|
|
what two motions appear to be decreased in patients with impingement syndrome?
|
scapular upward rotation and posterior tilt
|
|
if someone does not have appropriate scapular upward rotation, what motions would you advice them to avoid repeating?
|
flexion and abduction of the shoulder
|
|
appropriate upward rotation is necessary to maintain the correct length tension relationship of what muscle to prevent excessive shortening?
|
deltoid
|
|
what four motions do the rhomboids do?
|
(1) scapular ER
(2) scapular adduction (3) scapular elevation (4) scapular downward rotation |
|
what muscle is a prime stabilizer of the scapula during humeral motions with the arms below 90º?
|
rhomboids
|
|
what five motions does the levator scapulae do?
|
(1) scapular ER
(2) scapular downward rotation (3) scapular elevation (4) scapular adduction (5) slight scapular anterior tilt |
|
what two motions of the scapula are decreased with cervical flexion (50º)?
|
upward rotation and posterior tilt
|
|
shortness or stiffness of what three muscles will limit scapular upward rotation?
|
(1) latissimus dorsi
(2) rhomboids (3) levator scapulae |
|
lengthening of the pectoralis minor occurs when the arm is elevated into what two positions?
|
(1) flexion
(2) scaption |
|
subjects with short pectorals minors had greater __ __ during humeral elevation
|
anterior tilt
|
|
this muscle group acts to abduct the humerus
|
deltoids
|
|
what two motions does the anterior deltoid do?
|
(1) humeral IR
(2) horizontal adduction |
|
what motion does the middle deltoid do?
|
(1) humeral abduction
|
|
what two motions does the posterior deltoid do?
|
(1) humeral ER
(2) horizontal abduction |
|
what muscle has a larger moment arm at the beginning range of humeral abduction?
|
supraspinatus
|
|
what muscle acts to compress the humeral head into the glenoid, providing dynamic stability to the GH joint?
|
supraspinatus
|
|
contraction of the supraspinatus, infraspinatus, and subscapularis exert an __ force on the humeral head to offset superior migration
|
inferior
|
|
at what point of the range does the rotator cuff provide active tension to the GH joint?
|
midrange
|
|
at what point of the range does the rotator cuff provide passive tension to the GH joint?
|
at rest and extreme joint positions
|
|
loss of function of the rotator cuff muscles may result in __ movement of the humeral head becuase of the dominant pull of the deltoid
|
superior
|
|
given a patient with humeral superior glide and rotator cuff weakness, would you prefer to have the patient exercise with the arm moving into flexion or abduction?
|
flexion (because less of the deltoid is working, causing less superior glide and compression)
|
|
is the empty can or full can exercise preferred to exercise the supraspinatus?
|
full can (decreases chance of impingement)
|
|
the humerus needs to be in what position in order to use the biceps tendon to create a downward force on the humeral head?
|
external rotation
|
|
the rupture of this tendon removes the physical restraint to the humeral superor glide as well as the loss of active function
|
supraspinatus
|
|
the painful arc of motion between 60 and 120º is associated with rupture of what muscle tendon?
|
supraspinatus
|
|
what five muscles are humeral internal rotators?
|
(1) subscapularis
(2) teres major (3) latissimus dorsi (4) pectoralis major (5) anterior deltoid |
|
which of the humeral internal rotators attaches closest to the axis of motion and is therefore the best controller of motion?
|
subscapularis
|
|
what is the largest of the rotator cuff muscles, and the weakness of it contributes to anterior GH joint laxity?
|
subscapularis
|
|
contraction of what four muscles can internally rotate the scapula?
|
(1) infraspinatus
(2) teres minor (3) teres major (4) posterior deltoid |
|
what three muscles oppose scapular IR?
|
(1) rhomboids
(2) trapezius (3) serratus anterior |
|
shortness of the posterior scapulohumeral muscles may pull the scapula into what position during arm elevation?
|
upward rotation
|
|
at rest, shortness of the supraspinatus/deltoid results in what two motions?
|
humeral abduction and/or scpaular downward rotation (maybe some depression as well)
|
|
with the arm in flexion, the long head of the biceps acted as an __ rotator
|
internal
|
|
with the arm in abduction, the long head of the biceps acted as an __ rotator
|
external
|
|
these two muscles, by virtue of their humeral insertion, can pull the scapula forward on the thorax and into internal rotation
|
pec major and lats
|
|
what are the four primary muscles involved in shoulder extension/adduction?
|
(1) latissimus dorsi
(2) pectoralis major (3) teres major (4) posterior deltoid |
|
what muscles stabilize shoulder extension/adduction?
|
rhomboids, rotator cuff
|
|
contraction of the pectoralis major pull the humerus in what direction?
|
anterior
|
|
humeral impairments may be more noticeable during what arm motion?
|
abduction
|
|
what two possible contributing factors of muscle are there for decreased scapular upward rotation?
|
(1) decreased performance of upward rotators
(2) short/stiff or dominant downward rotators |
|
what two possible contributing factors of muscle are there for decreased scapular elevation?
|
(1) deficiency of elevation forces (long elevators)
(2) short/stiff or dominant depressors |
|
what two possible contributing factors of muscle are there for scapular winging/tilting?
|
(1) deficient scapulothoracic muscle timing
(2) excessive activity in the pectoralis minor and scapulohumeral mucsles |
|
what are two possible contributing factors for excessive humeral superior glide?
|
(1) weakness of the rotator cuff (deltoid more dominant)
(2) capsular restriction |
|
what are two possible contributing factors for excessive humeral anterior glide?
|
(1) deficiency of anterior structures (such as subscapularis weakness or laxity of anterior capsule)
(2) dominance of posterior structures (posterior deltoid, short/stiff posterior capsule and muscles) |
|
what stage of the tennis serve ends with the ball release from the left hand, has low forces, and there are no extremes of joint position here?
|
stage 1-wind up
|
|
what stage of the tennis serve is a gradual build up of power in the LEs greater than the UEs, and the shoulder moves into abduction and ER?
|
stage 2-early cocking
|
|
what stage of the tennis serve is a gradual build up of power, and full abduction and ER of the shoulder; need both static and dynamic stability, and there is an extreme of joint positions
|
stage 2-late cocking phase
|
|
what stage of the tennis serve is a release of power, starts when arm moves toward IR and ends with ball contact; requires power from shoulder IR, triceps, wrist flexors ?
|
stage 3-acceleration
|
|
what stage of the tennis serve is primarily eccentric muscle activity to decelerate the arm, and stress to posterior GHJ structures occurs, which may lead to stiffness/shortness posteriorly?
|
follow through
|
|
what phase of the baseball pitch is when there is flexion of the stride leg, flexion of extremities, and ends when the ball is removed from the glove?
|
stage 1-windup
|
|
what phase of the baseball throw is when the shoulder is is abduction, horizontal abduction, and external rotation?
|
phase 2-early cocking
|
|
what phase of the baseball throw starts with the contact of the stride foot with the ground; arm moves into maximal ER while staying abducted, and the trunk rotates forward?
|
phase 3-late cocking
|
|
what stage of the baseball pitch starts as soon as the arm moves toward IR from ER and ends with the ball release, and is a high velocity movement?
|
phase 4-acceleration
|
|
what stage of the baseball pitch is when deceleration of the arm occurs, dissipating forces; requires the posterior cuff, especially the teres minor and the subscapularis is also active to control humeral head; high distraction forces
|
phase 5-follow through
|
|
athletes, especially those that throw, often have increased range into what motion?
|
humeral external rotation
|
|
the __ capsule gets repetitive microtrauma during the follow through or deceleration phase of throwing sports, causing a posterior contracture
|
posterior
|
|
what type of joint is the elbow joint?
|
compound synovial joint
hinge joint |
|
what are the two components of the TRUE elbow joint?
|
(1) humeroulnar joint
(2) humeroradial joint |
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what type of joint is the humeroulnar joint?
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true hinge or modified hinge
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what type of joint is the humeroradial joint?
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arthrodial or gliding joint
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which direction is the axis of the elbow joint and what does it run through medially and laterally?
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medial to lateral; through epicondyle medially and capitulum laterally
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pulley shaped articular surface of distal humerus with a central groove
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trochlea
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anterior 1/2 of sphere at distal end of humerus that lies lateral to the trochlea
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capitulum
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the trochlea lies in front of the shaft of the humerus at a __º angle
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45
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the contact of the coronoid process with the humerus occurs only when the two bones are almost __
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parallel
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the boney structure of the trochlea of the humerus accounts for the __ __; the groover is vertical anteriorly but angled obliquely
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carrying angle
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is the medial or lateral lip of the trochlea increased in depth?
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medial
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what is the normal range of carrying angle?
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2-26º
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what is the functional consequence of the carrying angle?
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in full elbow extension the forearm is at an angle with the upper arm
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is the carrying angle greater in women or men?
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women
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what are three things that can alter the normal carrying (valgus) angle?
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(1) muscle pull
(2) laxity of ligaments (3) bony or articular changes |
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stiff wrist or finger __ may increase valgus forces at the elbow
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extensors
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a torn ___ ligament may increase elbow valgus
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MCL
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the trochlea is __ superior to inferior and __ medial to lateral
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concave; convex
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the head of the radius is __ proximally for flexion and extension
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concave
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the head of the radius articulates with the __ of the humerus
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capitulum
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the humeroradial joint functions during what two motions?
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(1) flexion/extension
(2) pronation/supination |
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the radius migrates proximally during forearm __
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pronation
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what are the two joints that are contained within the elbow joint capsule?
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true elbow joint (humeroradial and humeroulnar)
proximal radioulnar joint |
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what are the three muscles that the elbow joint capsule is closely related to?
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(1) brachialis
(2) triceps (3) anconeus |
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these two ligaments are thickenings of the elbow joint capsule medially and laterally; they function to prevent sidways movements and to keep the articular surfaces together
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collateral ligaments
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this band of the lateral collateral ligament is taut throughout flexion and extension
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anterior band
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this band of the lateral collateral ligament is from the latearl epicondyle to the supinator tubercle, and is the PRIMARY restraint to varus stress
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inferior band (lateral ulnar collateral ligament)
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what does varus instability manifest as clinically (from an injury to the LUCL)?
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posterolateral rotary instability
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the lateral collateral ligament complex is intimately blended with the origin of what two muscles?
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supinator and ECRB
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the lateral collateral ligament complex helps to reinforce what joint within the true elbow joint?
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humeroradial joint
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how many bands are there in the medial collateral ligament?
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3 (anterior, posterior, oblique)
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this band of the MCL is the primary stabilizer of the elbow to valgus stress from 20-120º
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anterior
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this part of the anterior band of the MCL is taut with elbow extension
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anterior
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this part of the anterior band of the MCL is taut with elbow flexion
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posterior
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this band of the MCL helps restrain valgus forces at 120º of flexion, and is taut with flexion
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posterior
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what are four activities that could cause valgus forces at the elbow, putting a strain on the MCL (especially the anterior band)?
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(1) tennis serve
(2) baseball pitch (3) resisted shouler medial rotation (4) resisted shoulder horizontal adduction |
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the MCL is closely related to what three structures?
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(1) triceps
(2) FCU (3) ulnar nerve |
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the cubital tunnel is formed by what two structures on the lateral side of the ulnar nerve?
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elbow joint and MCL
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the cubital tunnel is formed by what structure on the medial side of the ulnar nerve?
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fibrous aponeurosis between the two heads of the FCU
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what nerve runs through the cubital tunnel?
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ulnar nerve
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the cubital tunnel decreases in size by __% as you flex your elbow, which increases the pressure on the ulnar nerve
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55
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what is the normal range of active elbow flexion?
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145º
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what is the normal range of passive elbow flexion?
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160º
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what are five things that can limit the passive flexion range of motion of the elbow joint?
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(1) radius impacting radial fossa
(2) coronoid process on the coronoid fossa (3) tension of the posterior capsule (4) passive tension of extensor muscles and skin (5) posterior fibers of MCL |
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what is the normal range of extension of the elbow joint?
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0 to -5º
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hyperextension of the elbow joint is often due to what?
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a short olecranon
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what are three things that can limit the active and passive extension range of motion at the elbow joint?
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(1)olecranon on olecranon fossa
(2) anterior capsule and ligament (3) flexor muscles and skin |
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what are four things that forced elbow extension can result in?
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(1) fracture of olecranon
(2) torn anterior capsule (3) posterior dislocation of forearm bones relative to humerus (4) bruise or tear of brachial artery or median nerve |
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most activities of daily living can be accomplished with what range of elbow flexion?
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30-130º
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most activities of daily living can be accomplished with how many degrees of forearm pronation and supination?
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50º
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in the capsule pattern of the elbow joint, what motion is lost the most?
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flexion lost more than extension
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what are the three positions in the close packed position of the elbow joint?
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(1) ulnohumeral extension (olecranon in fossa)
(2) radiohumeral flexion (3) proximal radioulnar supination |
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this motion of the ulnohumeral joint is accompanied by slight internal rotation of the ulna
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pronation
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this motion of the ulnohumeral joint is accompanied by slight external rotation of the ulna
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supination
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what is the direction of the slide at the ulnohumeral joint during flexion?
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anterior
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what is the direction of the slide at the ulnohumeral joint during extension?
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posterior
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what is the direction of the slide at the ulnohumeral joint during varus angulation?
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lateral
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what is the direction of the slide at the ulnohumeral joint during valgus angulation?
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medial
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is the proximal radioulnar joint synovial or not?
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yes
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forearm pronation and supination involves these two joints that are mechanically linked
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proximal and distal radioulnar joints
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what type of joint are the proximal and distal RU joints?
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pivot
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the long axis of the radius is displaced laterally during what movement?
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pronation
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is the radial head longer in diameter from A to P or M to L?
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anterior to posterior
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with excessive __ to the forearm, the head of the radius can dislocate distally through the fibrosseous ring or annular ligament
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traction
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this ligament of the proximal RU joint is strengthened by the anterior fibers of the LCL and MCL; it attaches to the anterior and posterior margins of the radial notch of the ulna
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annular ligament
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this ligament of the RU joint is a fibrous band attached to the inferior border of the radial notch and to the neck of the radius; it limits rotation of hte radius in the fibrosseous ring (limits pronation and supination)
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quadrate ligament
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what is the normal range of forearm pronation?
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75º
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what is the normal range of forearm supination?
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85º
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the ROM of forearm pronation and supination is best assessed with the arm in what position?
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adducted
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what movement of the forearm increases the contact of the radius on the capitulum?
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pronation, elbow flexion
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what movement of the forearm decreases the contact of the radius on the capitulum?
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supination
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what does the longitudinal axis of the forearm run from?
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the head of the radius to the head of the ulna
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what is the direction of the roll and slide of the radius during pronation at the proximal radioulnar joint?
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anterior roll, posterior slide
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what is the direction of the roll and slide of the radius at the proximal RU joint during supination?
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posterior roll, anterior slide
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the movement of the radius on the capitulum is primarily __ during forearm pronation/supination
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spinning
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clinically, what type of glide of the radial head is occasionally seen during contraction of the biceps in patients with laxity of the annular ligament?
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anterior
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what type of joint is the middle RU joint?
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synarthroses (non-synovial)
NO CAPSULE |
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at the middle RU joint, this is a structure that is the site of muscle attachments; the fibers transfer forces and keep the radius and ulna in proper relationship with one another
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interosseous membrane
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the interosseous membrane is least taut with the forearm in what position?
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pronated with traction
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what is the order of force transmission from the interosseous ligament?
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hand to radius via the interosseous membrane to the ulna to the humerus
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this ligament of the middle RU joint is taut during supination and helps to check it
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oblique cord
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the radius is __ anteriorly and medially, allowing it to move over the ulna during pronation (increasing pronation ROM)
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concave
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what type of joint is the distal RU joint?
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pivot
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does it have its own capsule or is it included in the wrist joint capsule?
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its own capsule
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what is the close packed position of the distal RU joint?
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in neutral rotation or 5º supination
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the function of this structure at the distal RU joint is to bind the radius and the ulna together; provides dual articular surfaces and separates the radioulnar joint for the radiocarpal joint
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articular disc
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the articular disc of the distal RU joint is on maximum stretch in what position?
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neutral rotation
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what are the three intrinsic stabilizers of the distal RU joint?
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(1) joint capsule
(2) ligaments (3) TFCC |
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what are the four ligaments that stabilize the distal RU joint?
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(1) ulholunate ligament
(2) ulnotriquetral ligament (3) dorsal olblique bundle (4) palmar and dorsal RU ligaments |
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what are the two ligaments that are contained within the TFCC?
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ulnolunate and ulnotriquetral
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these ligaments of the distal RU joint help limit both pronation and supination
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dorsal and palmar radioulnar ligaments
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what are the two mucsles that stabilize the distal RU joint?
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(1) pronator quadratus
(2) tendon of the ECU |
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the cylindrical head of the ulna is __ at the distal RU joint
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convex
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the ulnar notch on the radius is __ at the distal RU joint
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concave
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what are six possible things that could limit forearm pronation?
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(1) impact of radius on ulna
(2) dorsal and palmar RU ligament tautness (3) TFCC (4) quadrate ligament (5) short muscles (supinator, biceps, ECRL) (6) decreased accessory ulnohumeral joint motions |
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what are three muscles whose shortness can cause limited pronation range?
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supinator
biceps ECRL (only if wrist flexed) |
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what are six things that could limit forearm supination?
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(1) oblique cord
(2) anterior and dorsal RU ligament tautness (3) TFCC (4) interosseous membrane (5) quadrate ligament (6) muscle shortness |
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what are two muscles whose shortness can cause limited supination range?
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pronators
finger flexors (if fingers extended) |
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clinically, forearm (supination, pronation) is restricted more often
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supination
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after injury, the forearm is immobilized in a position of forearm __
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pronation
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what is the axis of motion for forearm rotation with the forearm resting on the table?
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through small finger and medial edge of ulna
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with is the main movement during forearm rotation?
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rotational displacement of the lower end of the radius about the ulna
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during everyday movements, the axis of rotation for forearm rotation coincides with what?
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the axis of the hand (3rd MC)
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during pronation, what are the direction of the roll and slide of the radius on the ulna at the distal RU joint?
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anterior roll, anterior slide
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during supination, what are the direction of the roll and slide of the radius on the ulna at the distal RU joint?
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posterior roll, posterior slide
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what are the three muscles that may be the best at valgus motions of the elbow?
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ECRL
EDC ECU |
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what are the two mucles that may be the best at varus motions of the elbow?
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FDS
FCR |
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as a whole, which forearm muscles are more powerful, flexors or extensors?
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flexors
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what are the thre eprimary muscles of elbow flexion?
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(1) biceps
(2) brachialis (3) brachioradialis |
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the flexors produce maximal torque with the elbow flexed to __º
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90º
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the sole function of this muscle is elbow flexion; it does not pronate or supinate, and it has a large volume and PCSA so it can generate a lot of force
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brachialis
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what two nerves innervate the brachialis muscle?
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musculocutaneous and radial
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the brachialis and biceps create compressive forces at the elbow when they contract, so they may help increase __ stability when the LCL is deficient
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varus
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this muscle flexes the elbow and supinates the forearm, and is most active during flexion with the arm supinated
|
biceps
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what nerve innervates the biceps?
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musculocutaneous
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the function of this part of this muscle MAY play a role in restricting anterior and superior translation of the humeral head
|
long head of the biceps
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this muscle plays an important role in deceleration of the forearm during throwing; its pull on the glenoid labrum can cause labral injuries
|
biceps
|
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during elbow flexion, this muscle extends the shoulder, acting as a synergist to allow the biceps to function at a longer length and generate more force
|
posterior deltoid
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during resisted elbow flexion exercises, the scapular muscles have to stabilize the scapula to prevent the biceps from causing the scapula to go into what motion?
|
anterior tilt
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this muscle flexes the elbow, and with resistance, it assists with forearm pronation and supination; it is increased in activity with faster movements and with forearm semipronated
|
brachioradialis
|
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what nerve innervates the brachioradialis?
|
radial
|
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what are three accessory flexors of the elbow?
|
(1) FCR
(2) pronator teres (3) ECRL |
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the ECRL is the best at accessory flexing the elbow when the forearm is in what position?
|
pronated
|
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the FCR acts as an accessory elbow flexor at elbow angles of __º or more
|
50
|
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this elbow extensor has the largest volume and PCSA of all the muscles at the elbow; with pushing motions, you get elongation of the muscle over one joint and shortening over another joint
|
triceps
|
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what head of the triceps adducts and extends the shoulder, as well as extending the elbow?
|
long head
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what head of the triceps is most active ulness resistance is applied; it is the workhorse of the extensors
|
medial head
|
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the best moment arm for the triceps for elbow extension is at or near what position?
|
full extension
|
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the triceps produces maximal torque at __º of elbow flexion
|
90
|
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compressive forces by the triceps can increase __ stability in LCL insufficiency
|
varus
|
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this muscle is a deep extension from the medial head of the triceps that inserts into the capsule posterirly and helps pull the capsule taut during elbow extension
|
articularis cubiti
|
|
during pushing open a door, this muscle acts as a synergist with the triceps or a neutralizer flexing the shoulder during elbow extension to maintain the length of the triceps
|
anterior deltoid
|
|
this muscle extends the elbow and is recruited first for low level extensor force; it stabilizes the humeroulnar joint during elbow extension and forearm rotation motions
|
anconeus
|
|
what nerve innervates the triceps and anconeus?
|
radial
|
|
what two muscles are accessory extensors of the elbow?
|
FCU and ECU
|
|
what three muscles increased valgus stability at the elbow via compressive forces?
|
biceps
brachialis triceps |
|
the triceps exert greater compressive forces with the elbow in what position?
|
flexed
|
|
the biceps and the brachialis exert greater compressive forces with the elbow in what position?
|
extended
|
|
what two muscles increase valgus stability via producing a varus force secondary to the angle of pull?
|
FCU
FDS |
|
what three muscles increase varus stability at the elbow via compressive forces?
|
biceps
brachialis triceps |
|
during elbow flexion/extension exercises, forearm __ is the most stable position
|
pronation
|
|
during elbow flexion/extension exercises, avoid __ loaded positions or humeral __ and __
|
varus
medial rotation and abduction |
|
this muscle supinates the forearm; it is usually recruited before the biceps for isolated low power supination; under all conditions, but is a weaker supinator than the biceps
|
supinator
|
|
the fiber direction of this muscle may help to stabilize the head of the radius posteriorly (helps prevent anterior movement)
|
supinator
|
|
weakness of what muscle interferes with feeding oneself?
|
supinator
|
|
what innervates the supinator muscle?
|
radial nerve
|
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what muscle that flexes the elbow is also a powerful supinator?
|
biceps brachii
|
|
what are four acessory supinators?
|
finger and wrist extensors, EPL, EI
|
|
what muscle supinates the forearm from pronation (rotates the forearm to neutral regardless if forearm is pronated or supinated)?
|
brachioradialis
|
|
this muscle pronates the forearm and assist with elbow flexion; weaknes interferes with turning a door knob, using a knife, unscrewing, and is most active during high-powered activities
|
pronator teres
|
|
what nerve innervates the pronator teres?
|
median
|
|
this muscle is the primary pronator of the forearm, and helps stabilize the distal RU joint
|
pronator quadratus
|
|
what nerve innervates the pronator quadratus?
|
median
|
|
what three muscles assist in pronation?
|
FCR
palmaris longus brachioradialis |
|
what forearm muscles are stronger, supinators or pronators?
|
supinators
|
|
what forearm motion can be more easily compensated for, pronation or supination?
|
pronation
|
|
this muscle may help conteract the pull of the biceps on the radius during elbow flexion
|
supinator
|
|
the functional position of the forearm is best between what two positions?
|
neutral and semipronation
|
|
it is easier to lose ROM of what forearm movement, supination or pronation?
|
supination
|
|
this muscle could be underused in elbow problems
|
supinator
|
|
this DSM is when there are increased tensile forces at the medial elbow and compressive forces ont he lateral elbow
|
valgus
|
|
this DSM is when there is increased compressive and tensile forces on the ulnar nerve in the cubital tunnel
|
elbow flexion syndrome
|
|
this DSM is when there is increased compressive forces ont he lateral elbow and increased tensile forces on the medial elbow
|
increased carrying angle
|
|
a lesion at this nerve would cause you to lose function of the biceps and brachialis; marked decreased elbow flexion torque, and you may lose passive supination ROM since the forearm wil tend to pronate
|
musculocutaneous
|
|
lesion to this nerve will cause you to lose the pronator teres, but you will have minimal flexor torque deficit; may tend to lose forearm pronation ROM due to unbalanced biceps action (supinate as you flex)
|
median
|
|
what are four structures that resist longitudinal traction forces at the elbow?
|
(1) medial and lateral ligaments
(2) muscles (any arising from medial and lateral epicondyles, triceps) (3) annular ligament (traction on radius) (4) interosseous membrane |
|
this structure prevents distal movement of the radius relative to the ulna during longitudinal traction
|
interosseous membrane
|
|
this muscle may counteract the pull of the biceps on the radius with the elbow at 90º of flexion (if the annular ligament is injured)
|
supinator
|
|
impacting forces may result in fractures of what two structures in the forearm?
|
radial head
coronoid process |
|
impacting forces may result in dislocation in what direction of the elbow joint?
|
posterior
|