Elbow and Arm Flashcards
What are routine x-ray projections of the elbow?
AP and Lateral
What are routine x-ray projections of the Humerus?
AP and Lateral
What are some clinical indications for the elbow?
Trauma
Bony tenderness
Suspected fracture of the proximal radius and ulna
Suspected fracture of the distal humerus
Radial head dislocations
Obvious deformity
Detecting joint effusions
Arthritis
Infection
What are additional projections of the elbow?
Coyle’s projection and Jones Orthopaedic Projection
What can a Coyle’s projection show?
Radial head Fx or dislocation
Capitellum Fx
How does the arm need to be positioned for a Coyle’s projection?
X-ray beam at 45 degrees
Radial head isolated,
Radiocapitellar joint open
What can a Jones Orthopaedic Projection show?
Good for a Pt. who cannot straighten arm d/t pain
suspected supracondylar fractures in younger patients
Intra-articular loose bodies
What are the names of the anterior fat pads?
Coronoid Fat Pad
Radial Fat Pad
What is the name of the posterior fat pad?
Olecranon fat pad
What is the anterior humeral line?
Line of measurement
Draw a line down anterior surface of Humerus
It should intersect the middle 1/3 of the Capitellum
What does FOOSH stand for?
Fall onto out stretched hand
What is the radiocapitellar line?
Line of measurement
Line drawn down the neck of the Radius
Should intersect the Capitulum
Line must run along Radial Neck and not shaft of Radius due to the slight angulation of the neck of the Radius
What could a fat pad sail sign be indicative of in adults?
Radial head fracture
What could a fat pad sail sign be indicative of in Children?
Supracondylar fracture
What could a posterior fat pad abnormality indicate in adults?
non-displaced occult radial head fracture
What could a posterior fat pad abnormality indicate in children?
non-displaced occult supracondylar fracture
What is Olecranon Foramen?
Normal anatomical variant of the Olecranon Fossa (also known as Septal Aperture or Supratrochlear Foramen)
In an x-ray - Increased lucency in the distal Humerus at the Olecranon Fossa
What causes an Olecranon Foramen?
An aperture formed by the failure of ossification of the septum that separates the coronoid and olecranon fossae
What is Radioulnar Synostosis?
Abnormal connection between the Radius and Ulna
How is Radioulnar Synostosis diagnosed?
Reduced RoM, usually pronation and supination of hand.
Not usually painful unless it causes subluxation of Radial Head
X-ray : bony fusion and continuous cortex between the proximal radius and ulnar with no radioulnar joint space
What is the clinical significance of radioulnar synostosis?
Can be associated with dislocation of the Radial Head
What is the Supracondylar Process of Humerus?
Bony spur projecting distally on the anteromedial surface of the Humerus, approximately 5cm above medial epicondyle.
“Struthers Ligament” may connect spur to medial epicondyle
What does Supracondylar Process of Humerus display like on an x-ray?
small bony spur projecting anteromedially from the humeral metadiaphysis towards theelbow joint.
What does occult mean?
not accompanied by readily discernible signs or symptoms
What causes radial head fracture?
Indirect trauma, fall onto abducted arm with slight flexion of elbow joint
What does a radial fracture look like on an x-ray?
Can be Occult – Sail Sign / posterior fat pad sign
Radiolucent line; break in the cortex; displacement of cortex
what is a Radial Tuberosity Pseudocyst/tumour?
anatomical variant that mimics a bone lesion
What causes a Radial Tuberosity Pseudocyst/tumour?
The radial tuberosity has an area of focal trabeculae rarefaction as it is a “low stress” region
How does a Radial Tuberosity Pseudocyst/tumour display on x-ray?
lateral projection – ovoid radiolucent lesion (tumour or cyst-like appearance)
What is the clinical significance of a Radial Tuberosity Pseudocyst/tumour?
misdiagnosed as bone tumour or cyst
Artefactual – misrepresentations of natural tissue due to imaging technique
What is the clinical considerations of a Humeral Head Pseudocyst/tumour
misdiagnosed as bone tumour or cyst
“do not touch” lesion
What causes a Humeral Head Pseudocyst/tumour?
Greater tuberosity of the humeral head has greater quantity of spongy bone
What is a Prominent Deltoid Insertion?
anatomical variant that mimics a bone lesion
What does a prominent deltoid insertion look like on an x-ray?
localised cortical thickening of the lateral humeral midshaft at the insertion site of the deltoid muscle
clinical significance - resembles periostitis and may be mistaken for a lesion
What is the name of the accessory ossicle of the elbow?
Os Supratrochlear Dorsale
Where is the Os Supratrochlear Dorsale located?
Olecranon fossa of humerus
What is the name of the sesamoid bone of the elbow?
Patella Cubiti
Where is the Patella Cubiti located?
Distal Triceps Brachii
Similar appearance to Patella on x-ray
What does CRITOE stand for?
6 elbow ossification centres
Capitellum
Radial Head
Internal (medial) epicondyle
Trochlea
Olecranon
External (lateral) epicondyle
At what age does the capitellum ossify?
1 year old
At what age does the radial head ossify?
3 years old
At what age does the internal (medial) epicondyle ossify?
5 years old
At what age does the Trochlea ossify?
7 years old
At what age does the olecranon ossify?
9 years old
At what age does the External (lateral) epicondyle ossify?
11 years old
