Pediatric elbow radiographs are commonly encountered in the emergency department and, when approached in a systematic fashion, are not as difficult to interpret as most people think!
On this page:
Systematic review
Ossification
Check that the ossification centers are present and in the correct position. They appear in a predictable order and can be remembered by the mnemonic CRITOE (age of appearance are approximate):
- capitellum (age 1)
- radial head (age 3)
- internal epicondyle (age 5)
- trochlea (age 7)
- olecranon (age 9)
- external epicondyle (age 11)
Alignment
Check the anterior humeral line:
- drawn down the anterior surface of the humerus
- should intersect the middle 1/3 of the capitellum
- if it does not, think supracondylar fracture
(under the age of 4, the line will intersect the anterior 1/3)
Check the radiocapitellar line:
- drawn along the radial neck
- should always intersect the capitellum
- if it does not, think radial head dislocation
- check for an accompanying fracture, e.g. Monteggia fracture-dislocation
Effusion
Check for raised fat pads:
- visible posterior fat pad always indicates an elbow effusion
- visible anterior fat pad may be seen in normal patients and should only be thought of as an indicator of an elbow effusion when massively raised
- if there is an effusion in a pediatric patient, think supracondylar fracture or intra-articular fracture, e.g. lateral condyle fracture
Bone cortex
Check around every bone on the film:
- helps to find subtle injuries, e.g. minimally displaced supracondylar fracture or olecranon fracture
- look at areas where common injuries occur first (distal humerus and radial neck)
Common pathology
Supracondylar fracture
- over 60% of all pediatric elbow injuries
- peak age: 5-7 years
- mechanism: fall onto a hyperextended elbow
- extra-articular fracture
- there may be posterior displacement of the distal segment
- more: supracondylar fracture
Lateral condyle fracture
- 10-20% of all pediatric elbow injuries
- peak age: 6-10 years
- mechanism: usually varus force applied to an extended elbow
- unstable intra-articular fracture
- prone to displacement due to the pull of forearm extensors
- more: lateral condyle fracture
Medial epicondyle avulsion
- 10% of all pediatric elbow injuries
- usually older children and adolescents
- mechanism: FOOSH with full elbow flexion, or posterior elbow dislocation
- most common avulsion injury
- more: medial epicondyle fracture
Radial head dislocation
- 5% of all pediatric elbow injuries
- typically seen in infancy and childhood
- mechanism: isolated traumatic injury
- the radial head is dislocated anteriorly
- check for associated ulnar fracture (Monteggia fracture-dislocation)
- more: radial head dislocation
Radial neck fracture
- 5% of all pediatric elbow fractures
- peak age: 8-11 years
- mechanism: FOOSH with extended elbow and supinated forearm
- most fractures involve the physis
- more: radial neck fracture
Don't miss...
Olecranon fracture
- <5% of all pediatric elbow injuries
- less common in children than adults
- mechanism: either a direct blow, fall on an outstretched hand with flexed elbow, avulsion fracture or stress fracture
- frequently associated with radial neck fracture and elbow dislocation
- more: olecranon fracture
Unable to process the form. Check for errors and try again.