Lecture 3 Flashcards
(17 cards)
What are the movements capable of the arm as a result of the elbow?
Arm can flex, allow forearm to rotate-pronate and supinate
What are the main causes of elbow injuries?
Falling or throwing
Children have greater incidence of supracondylar fractures
Adults have greater incidence of radial head fractures
Why are elbow injuries recalling concerning?
Leads to serious complications due to close proximity to major blood vessels and nerves
Discuss the order of the ossification centres in the elbow regions
CRMTOL
Capitellum (age 1) Radial head (3) Medial epicondyle (5) Trochlea (7) Olecranon (9) Lateral epicondyle (11)
What does a displaced or elevated fat pad of olecranon and coronoid fossa suggest?
On a correctly positioned lateral elbow, it indicates a probable supracondylar fracture of distal humerus, and displacement of proximal radius
What is the sublime tubercle?
On the proximal ulna
It is an insertion point for the ulnar collateral ligament
What does the elevation of the supinator fat stripe (proximal end of radius) suggest on a lateral elbow scan?
Can indicate a fracture of radial head or neck
Not as reliable as anterior and posterior fat pads
Can sometimes reflect as to what’s happening near the anterior fat pad region but that’s not that common
How can we verify that all regions in the elbow are in alignment?
Look at regions of intersections with the radiocapitellar line and anterior humeral line
Long axis of radial neck (proximal radial line) must pass through the capitellum epiphysis. This rule applies in both AP and lateral
Lateral elbow, the anterior humeral line goes down the anterior cortex of humerus and must pass through the middle 3rd of capitellum
The lines will always intersect at the capitellum at whatever rotation cause articulation with capitellum is inevitable anatomically
Explain what a ‘pulled elbow’ injury is
Arm of child pulled (1.5 - 4 yo common)
Forearm pronates and elbow slightly hyperextended. Can clause radius to become displaced anteriorly because the force causes radial head to subluxate from annular ligament and then the muscle pulls radial head inferiorly as there is no ligament holding it.
Very painful elbow and unable/reluctant to move the arm, arm hanging slightly flexed and pronates
Always check for other pathologies on pt. Who’s experienced probation and hyperextension of elbow
What is a supracondylar fracture?
Fall on extended or hyperextended elbow, can also lead to fracture of lower end radius/ulna in 10% cases
There are 3 types in the Garland classification
Explain the 3 types of supracondylar fracture classifications
Type 1 - undisplaced ie. hairline fractures
Type 2- displaced with in tact cortex
Type 3 - completely displaced ie. both anterior and posterior wall. Can cause vascular damage (brachial artery), nerve impingement (median nerve) or injury to brachialis muscle either by entrapment in the fragment or a bone fragment piercing the muscle. No fat pads visible
What has to be done when the supracondylar fracture is classifies as type 3?
Colour and temperature of hand assessment done
ORIF with k-wire to avoid compartment syndrome (pressure buildup from internal swelling or bleeding) caused by amount of associated swelling
When are the fat pads visible and when are they not?
Elbow fat pads appear when fractured humeral region is intra capsular or the fracture is not markedly displaced
When fracture is displaced and has disrupted the capsule there will be no fat pads visible (like in type 3 supracondylar)
Exaplin the fractures of the radial head and neck
Due to FOOSH with partial flexsion or pronation of elbow or direct axial load from FOOSH with extended elbow
Radial head fractures common in adults (20% of elbow fractures)
Radial neck fractures common in children (because anterolateral portion of radial head has no osteochondral support and fractures easily)
What are the symptoms of radial head and or neck fracture?
Instant pain in joint which becomes more severe as it swells. Pain on pronation and supination of forearm.
Presentation= cradling elbow, flexed 80 deg (reduces pain from effusion)
Swelling and bruising over lateral elbow
Explain the classification of radial head and neck fractures
Type 1 = non-displaced radial head fractures (or small marginal fracture) known as a chisel fracture. Treated conservatively
Type 2 = partial articular fracture with displacement (>2 mm). Treated with ORIF
Type 3= comminuted fracture involving entire head
- a3 ; fracture of entire neck and head
- b3; articular fracture involving entire head, consisting of more than 2 large fragments
- c3; fracture with a tilted and impacted articular segment
(Require early complete excision of radial head as it isn’t reconstructible)
Type 4 = fracture of radial head with dislocation of elbow joint
Explain what is a medial epicondyle fracture?
Common in children >5 and around 10% of elbow injuries
Avulsion fracture caused by valgus force and contraction of common flexor tendons
Can be due to fall on arm, fully extended elbow and common flexor pronator being avulsed, posterior elbow dislocation transmitting force to medial epicondyle via ulna collateral ligament (less common)
Medial epicondylitis = climbers/golfers can lead to avulsion fracture
