General Concepts, Overview 2 Flashcards
what is preemptive analgesia? why does it work?
pre-incisional local anesthesia in addition to general anesthesia
help block pain impulses and sensitization
what contributes to dynamic stability of the glenohumeral joint? static stability?
- dynamic - rotator cuff muscles
2. static - glenoid fossa, labrum, ligaments
what ligament in the shoulder joint holds the tendon of the long head of biceps brachii? where does it run?
transverse humeral ligament
between the greater and the lesser trochanter
what ligament maintains the integrity of the superior glenohumeral joint?
anterior?
coracohumeral ligament
glenohumeral ligaments (anterior)
what are the rotator cuff muscles? (list them)
when do they ALL do?
supraspinatus, infraspinatus, teres minor, subscapularis
pull the humeral head towards the center of the fossa, keeping it centered and keeping the humeral head to hitting the acromion as the humerus is abducted
During abduction, the __________ must pivot to rotate the glenoid cavity and acromion upwards. This upward tilt starts at:
around _____ of abduction and continues to approximately _____ of abduction
scapula
30°, 120°
what muscles tilt the glenoid (of scapula) up?
trapezius, serratus anterior
the humerus must be __________ rotated (beginning at around ____° of abduction)
why?
what muscles do this?
laterally, 90 degrees
to move the greater tubercle out from under the acromion
teres minor and infraspinatus
abduction of the arm is initiated by activation of what 2 muscles: (0-30 degrees)
supraspinatus and deltoideus
controlled trials demonstrate efficacy of acupuncture in what areas/types of pain?
low back pain
knee osteoarthtitis
migraine headaches
labor
what is the chinese medicine rational for how acupuncture works? Western medicine?
chinese medicine: the acupuncture points with needles help relief of stagnation of chi –> relief of pain
western medicine: release of natural opioids
compression of subacromial soft tissues between the proximal humerus and acromion: ____________________________
impingement syndrome
what muscles are usually affected in impingement syndrome?
long head of biceps brachii
supraspinatus
describe the phenomenon of the “painful arc”. what syndrome is this associated with?
impingement syndrome
first part of abduction done without pain, but at about 6-120 degrees, there is pain (where the space under the acromion is smallest).
then from 120-180 degrees, no pain again
explain the pathophysiology behind mild, moderate, and secure impingement syndrome:
what are the presentations on physical exam?
Mild: edema, hemorrhage of subacromial soft tissues. Painful arc and NO weakness
Moderate: tendinitis (usually supraspinalis), painful arc and NO weakness but PAIN to resistance
Severe: tendon tear/rupture + inflammation, painful arc and WEAKNESS
anterior dislocation can damage what nerve?
axillary nerve
what is “dead arm syndrome”? when do you see it most often?
damage to the axillary n.
loss of sensation over deltoid, decreased strength in abduction
anterior dislocation
what motions give you pain with anterior shoulder laxity?
abduction and lateral rotation
what motions give you pain with posterior shoulder laxity?
adduction and internal rotation
describe the apprehension test. what is it for?
it is for anterior shoulder laxity
abduct and laterally rotate shoulder, push femoral head forward. if they have fear or do not let you continue, it is positive
what is a “burner”/”stinger”? (specific location)
when do they resolve?
clinical presentation?
result of trauma to the neck/shoulder that affect 5th and 6th cervical nerve roots
usually resolve in hours to weeks
anesthesia, weakness, and dyesthesia
define internal validity:
the study design performance at measuring differences between groups, if there is one, that are due only to the hypothesized effect
MEASURE OF STUDY DESIGN
why is concealment important for internal validity of an RCT?
decreases placebo effect and bias (patients or investigators minimizing or maximizing symptoms)
