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Flashcards in Elbow Deck (31):

Elbow Complex

made up of three articulations:
humeroulnar joint
humeroradial joint
proximal radioulnar joint


Monteggia Fracture

fracture of the proximal ulna with radial head dislocation, often classified by the direction of radial head dislocation


Type 1 Monteggia Fracture

60% of the time
anterior radial head dislocation with palmar angulation


Humeroulnar joint

uniaxial hindge between the trochlear notch of the proximal ulna and the trochlea of the humerus
carrying angle: 11-14 in males and 13-16 in females


humeroulnar joint open pack position

70 deg of flexion and 10 deg supination


humeroulnar joint close pack position

full extension and maximum forearm supination


cubital valgus

increased angulation
can be caused by lateral epicondylar fracture


cubital varus

decrease in carrying angle
aka gunstock deformity
usually a supracondylar fracture due to extension injury


Humeroradial joint

uniaxial hinge between capitellum of humerus and concave head of the radius


open pack position of the humeroradial joint

extension and forearm supination


close pack position of the humeroradial joint

90 deg elbox flexion and 5 deg supination


Proximal radioulnar joint

uniaxial pivot between radial head and radial notch of the ulna
annular ligament forms 80% of the articular surface


open pack position of the Proximal radioulnar joint

70 deg flexion and 35 deg forearm supination


close pack position of the Proximal radioulnar joint

5 deg forearm spunation


Annular ligament

maintains the relationship between the head of teh radius and the humerus and ulna


Nursemaids elbow

aka pulled elbow
radial head slippage from under the annular ligament trapping the ligament in the radiohumeral articulation


Elbow joint capsule

thin but strong
does not respond well to injury or prolonged immobilization and commonly forms thick scar tissue which may result in flexion contractures of the elbow


Medial Collateral Ligament

functionally most important ligament in the elbow for providing stability against valgus stress
three components:
anterior bundle
transverse bundle
posterior bundle


Anterior bundle of the MCL

anterior band is the strongest and stiffest, stabilizes the elbow against valgus stress in 20-120 deg of flexion
posterior band is taut beyond 55 deg of elbow flexion, primary restraint to passive elbow extension, equal co-restraint with the anterior band at terminal elbow flexion, resists valgus stress


transverse bundle of the MCL

aka coopers ligament
fibers originate and insert on the ulna and have little role in elbow stability


posterior bundle of the MCL

a thickening of the posterior elbow capsule
provides secondary restraint to valgus stress at greater than 90 deg flexion


little leaguer's elbow

avulsion of the medial epicondyle
usually found in child or adolescent and is associated with sports requiring strong throwing motions
overuse injury


Lateral collateral ligament of the elbow

consists of annular ligament, fan-like radial collateral ligament, accessory collateral ligament, and lateral ulnar collateral ligament
functions to maintain the ulnohumeral and radiohumeral joints in a reduced position when the elbow is loaded in supination


Olecranon bursa

main bursa of the elbow complex, lies posteriorly between the skin and olecranon process


Olecranon bursitis

aka miners elbow/ student's elbow
chronic or acute trauma to the tip of the elbow


Myositis Ossificans Elbow Flexor

most common sites are brachialis anterior, quad, adductor, and MCL of the knee
most occur following any local injury sufficient to cause bruising or frank hemmorhage within a muscle
heterotrophic bone formation in the soft tissue


Contents of the cubital fossa

biceps tendon
median nerve
brachial artery
radial nerve
median cubital or intermediate cubital cutaneous vein


elbow flexion

150 degrees


elbow extension

0 degrees


forearm supination

80 degrees
at radio-ulnar joint


forearm pronation

80 degrees