Joints of Upper Limb Flashcards
Shoulder girdle
made up of scapula and clavicles
incomplete bony ring
attach anteriorly to manubrium of sternum
True articulations of shoulder girdle (synovial joints)
sternoclavicular joint
acromioclavicular joint
glenohumeral joint
scapulothoracic articulation
Sternoclavicular joint
synovial, saddle joint
includes: sternal end of clavicle, manubrium of sternum, 1st costal cartilage
only articulation between upper limb and axial skeleton
Articular disc of sternoclavicular joint
divides the joint space into 2 compartments
serves as shock absorber
Clavicle fracture
common fracture site
usually in middle 1/3
usually caused from a fall on an outstretched arm
Acromioclavicular joint
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
Coracoclavicular Ligaments (AC joint)
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
AC joint dislocation
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
Glenohumeral Joint
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
Glenohumeral ligaments
strengthen anterior aspect of capsule
intrinsic ligaments
superior, middle, inferior ligaments
Coracohumeral ligament
From coracoid process to anterior aspect of greater tubercle
part of fibrous capsule (intrinsic ligament)
strengthen and stabilizes capsule superiorly
Transverse humeral ligament
Greater to lesser tubercle
holds the long head of the biceps brachii tendon in place
loosening can cause tendon jumping
overtop of biceps
Coracoacromial Ligament
spans between coracoid process and acromion process
strong superior support
prevents dislocation of humerus
GH Dislocation
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
Blood supply of GH joint
anterior and posterior circumflex aa
suprascapular branches
innervation of GH joint
suprascapular n, axillary n, lateral pectoral n
Olecranon Bursitis
inflammation of bursa overlying olecranon
common in labor intensive jobs, or even bug bite
Clin pres: redness, swelling, pain
Treatment: remove via aspiration, NSAIDs
Elbow joint
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
Radial Collateral Ligament
lateral aspect
fan-like thickening of joint capsule
lateral epicondyle to annular ligament
prevents against varus force- medial impact
ulnar collateral ligament
medial aspect
triangular (3 bands)
medial epicondyle to olecranon
prevents against valgus force- lateral force
Ulnar collateral ligament tear
baseball players, football players, javelin throwers
constant rotation at ulna
Annular ligament
encircles and holds head of radius in the radial notch of the ulna
permits pronation and supination of forearm
Subluxation and Dislocation of Radial Head
common in kids
Clin Pres: pain, lack of use of arm
can come from lifting and swinging of children
Blood supply of proximal radioulnar joint
derived from anastomosis around elbow
Innervation of proximal radioulnar joint
radial, median, ulnar nn
Distal radioulnar joint
synovial, pivot joint
head of ulna to ulnar notch of radius
articular disc binds ulna and radius- triangular ligament
radius moves around ulna
wrist joint (radiocarpal)
synovial condyloid joint
between radius, scaphoid, lunate, triquetrum
not ulna
scaphoid fracture
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
Erb-Duchenne Palsy
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
damage to ulnar n
elbow and wrist
superficial at wrist- pisiform and hook of hamate
ulnar nerve palsy
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
Sign of Benediction
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
wrist drop
damage to radial n by humerus break
unopposed flexion of digits
Klumpke paralysis
stretch or tear of C8-T1
increase angle between limb and trunk
injury to lower brachial plexus
complete claw hand
Klumpke vs Thoracic outlet syndrome
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
