Joints of Upper Limb

Question 1

Shoulder girdle

Answer 1

made up of scapula and clavicles
incomplete bony ring
attach anteriorly to manubrium of sternum

Question 2

True articulations of shoulder girdle (synovial joints)

Answer 2

sternoclavicular joint
acromioclavicular joint
glenohumeral joint
scapulothoracic articulation

Question 3

Sternoclavicular joint

Answer 3

synovial, saddle joint
includes: sternal end of clavicle, manubrium of sternum, 1st costal cartilage
only articulation between upper limb and axial skeleton

Question 4

Articular disc of sternoclavicular joint

Answer 4

divides the joint space into 2 compartments
serves as shock absorber

Question 5

Clavicle fracture

Answer 5

common fracture site
usually in middle 1/3
usually caused from a fall on an outstretched arm

Question 6

Acromioclavicular joint

Answer 6

synovial, plane (gliding) joint
includes acromion of scapula and lateral end of clavicle
Loose fibrous joint capsule:
allows for rotation of the acromion process on the end of the clavicle
no muscles move joint directly
acromioclavicular ligament: strengthens AC joint superiorly

Question 7

Coracoclavicular Ligaments (AC joint)

Answer 7

accessory ligament
anchors clavicle to coracoid process
Conoid ligament: medial and posterior
trapezoid ligament: lateral and anterior
main stabilizer of AC joint
prevents superior translation of clavicle- prevents clavicle from going above acromion

Question 8

AC joint dislocation

Answer 8

shoulder separation
2 types: with and without ligament rupture
without = fall on elbow
with = fall directly on shoulder
common in hockey players getting checked into boards

Question 9

Glenohumeral Joint

Answer 9

synovial ball and socket
very mobile and unstable
more prone to injury
Articulation:
large humeral head and shallow gleniod cavity
deepened by glenoid labrum
loose fibrous joint capsule strengthened and stabilized by rotator cuff muscles
long head of biceps and subtendinous bursa run through

Question 10

Glenohumeral ligaments

Answer 10

strengthen anterior aspect of capsule
intrinsic ligaments
superior, middle, inferior ligaments

Question 11

Coracohumeral ligament

Answer 11

From coracoid process to anterior aspect of greater tubercle
part of fibrous capsule (intrinsic ligament)
strengthen and stabilizes capsule superiorly

Question 12

Transverse humeral ligament

Answer 12

Greater to lesser tubercle
holds the long head of the biceps brachii tendon in place
loosening can cause tendon jumping
overtop of biceps

Question 13

Coracoacromial Ligament

Answer 13

spans between coracoid process and acromion process
strong superior support
prevents dislocation of humerus

Question 14

GH Dislocation

Answer 14

anterior most common
posterior rare
inferior least common
Name indicates where humeral head is positioned
anterior dislocation: head of humerus popping out, anterior impact, arm abducted
inferior dislocation: most in males, head of humerus inferiorly out, MVA
GH capsule is vulnerable and loose in anterior-inferior aspect
Median, radial, and axillary nn at risk

Question 15

Blood supply of GH joint

Answer 15

anterior and posterior circumflex aa
suprascapular branches

Question 16

innervation of GH joint

Answer 16

suprascapular n, axillary n, lateral pectoral n

Question 17

Olecranon Bursitis

Answer 17

inflammation of bursa overlying olecranon
common in labor intensive jobs, or even bug bite
Clin pres: redness, swelling, pain
Treatment: remove via aspiration, NSAIDs

Question 18

Elbow joint

Answer 18

synovial, hinge joint
3 joints: humeroulnar, humeroradial, proximal radioulnar
fibrous joint capsule:
weak anteriorly and posteriorly
covers all 3 articulations
loose for full flexion and extension

Question 19

Radial Collateral Ligament

Answer 19

lateral aspect
fan-like thickening of joint capsule
lateral epicondyle to annular ligament
prevents against varus force- medial impact

Question 20

ulnar collateral ligament

Answer 20

medial aspect
triangular (3 bands)
medial epicondyle to olecranon
prevents against valgus force- lateral force

Question 21

Ulnar collateral ligament tear

Answer 21

baseball players, football players, javelin throwers
constant rotation at ulna

Question 22

Annular ligament

Answer 22

encircles and holds head of radius in the radial notch of the ulna
permits pronation and supination of forearm

Question 23

Subluxation and Dislocation of Radial Head

Answer 23

common in kids
Clin Pres: pain, lack of use of arm
can come from lifting and swinging of children

Question 24

Blood supply of proximal radioulnar joint

Answer 24

derived from anastomosis around elbow

Question 25

Innervation of proximal radioulnar joint

Answer 25

radial, median, ulnar nn

Question 26

Distal radioulnar joint

Answer 26

synovial, pivot joint
head of ulna to ulnar notch of radius
articular disc binds ulna and radius- triangular ligament
radius moves around ulna

Question 27

wrist joint (radiocarpal)

Answer 27

synovial condyloid joint
between radius, scaphoid, lunate, triquetrum
not ulna

Question 28

scaphoid fracture

Answer 28

most commonly fractures carpal bone
blood supplied by radial a but there is poor blood supply to proximal pole-waist of bone
Clin Features:
pain over snuff box
often confused with wrist sprain
can have bone necrosis with recurring blood supply from radial a

Question 29

Erb-Duchenne Palsy

Answer 29

Damage to superior trunk- C5-C6
causes waiter’s tip appearance
typically at birth- increase angle between shoulder and head
internally rotated shoulder
pronated wrist
elbow extended
presentation comes from inability to flex but latissimus dorsi and triceps has unopposed force

Question 30

damage to ulnar n

Answer 30

elbow and wrist
superficial at wrist- pisiform and hook of hamate

Question 31

ulnar nerve palsy

Answer 31

causes claw hand
ulnar nerve entrapment
loss of inn to intrinsic hand muscles
cutaneous inn to ring and pinkie
cannot extend digits 4-5
flexor digitorum profundus has unopposed flexion

Question 32

Sign of Benediction

Answer 32

damage to median n at elbow or forearm
loss of inn to 5 intrinsic muscles in hand
cannot make fist
damage at elbow = cannot make okay sign, lost flex. pollicis longus and flex. digitorum superior and profundus- cannot curl

Question 33

wrist drop

Answer 33

damage to radial n by humerus break
unopposed flexion of digits

Question 34

Klumpke paralysis

Answer 34

stretch or tear of C8-T1
increase angle between limb and trunk
injury to lower brachial plexus
complete claw hand

Question 35

Klumpke vs Thoracic outlet syndrome

Answer 35

similar clinical pres
in thoracic outlet syndrome you see other things such as damage to blood supply, autonomic effects, result of tumor, cervical rib- more effects than just hand