Angles Flashcards
To memorise the angles in various x-ray image projections.
Where is the centre point for a finger projection (PA, Lateral and Oblique)?
Proximal-Inter-Phalangeal (PIP) Joint (first joint above knuckles)
What is the film size for a finger projection?
18 x 24
What is the centre point for a thumb projection?
1st Metacarpophalangeal (MCP) joint (knuckles), AKA thumb knuckle
What is the film size for a thumb projection?
18 x 24
What is the collimation for a thumb projection?
Distal phalanx (finger) to trapezium (bone directly under thumb)
What is the centre point for a PA or Oblique hand x-ray?
Head of the 3rd Metacarpal (3rd knuckle)
What is the centre point for a Lateral hand x-ray?
Head of the 2rd Metacarpal (2nd knuckle from the thumb)
What is the collimation for a hand x-ray?
Distal Radius & Ulna to distal Phalanges (fingers)
What is the elbow angle for a hand x-ray?
90 degrees
What is a Norgaard Series?
PA bilateral hands, and “ball catchers” bilateral hands. Film size is 24 x 30
What is the centre point for a wrist x-ray?
Lateral: radial styloid process
PA or Oblique: between radial and ulnar styloid processes
What is the elbow angle for a wrist x-ray?
90 degrees
What is the collimation for a wrist x-ray?
Distal 1/3rd of radius and ulna to mid-MC (middle of palm)
What deviation of the hand is used for a scaphoid image?
Ulna deviation, external/ lateral deviation
What angle is used for a scaphoid x-ray?
30 degrees towards elbow (cephalad technically)
What is in a scaphoid series?
PA wrist, Oblique wrist and angled PA - all with ulnar deviations. And then a lateral wrist
What is the centre point for a lateral and AP forearm
Mid forearm
What direction should the hand face for a AP forearm?
Hand supinated, palm up
What angle should the elbow be for a lateral forearm?
90 degrees, thumb facing upward
What positions are in a elbow series
AP, external oblique, and lateral
What is the technique for a radial head projection?
- 45 degree cephalad tilt (along humerus)
- Patient perpendicular to table
- elbow flexed at a 90 degree angle
- centre point is radial head
What is in a trauma shoulder series?
AP, Glenohumeral joint, lateral
What is the technique for a AP shoulder?
Positioning: internal or external rotation, just ensure the opposite is done for the GH
Centre point: 2.5cm inferior to coracoid process
Central Ray: perpendicular to patient
Collimation: include clavicle, scapula and soft tissue
What is the technique for a GH shoulder?
Positioning: patient rotated 35-45 degrees facing the beam, affected side on plate, opposite hand rotation to AP
Centre point: GH joint
Central Ray: 15-20 degrees caudad
Collimation: tight to GH
What is the technique for a lateral shoulder
Positioning: patient facing the buckey, rotate 45-60 degrees to IP, affected side on IP, hand on tummy
Centre point: mid scapula
Central ray: perpendicular
Collimation: to include scapula and acromion
What is in a chronic shoulder series?
AP, GH, Neer’s and SI (Axial)
What is a Neer’s projection?
A shoulder projection of joint outlet
Positioning: patient facing bucky, body rotated 45-60 degrees, affected side on IP, arm by side or across abdomen
Centre point: humeral head or mid-scapula, depending on request
Central ray: 10-15 degrees caudad
Collimation: tight to outlet or whole scapula, depending on request
What is a SI (axial) projection?
Positioning: patient sitting, arm abducted, elbow flexed 90 degrees, head tilted away from affected side as much as possible
Centre point: shoulder joint
Central ray: 5-15 degrees to elbow (caudad)
Collimation: soft tissue and joint
What is the difference between a 1st presentation clavicle and a follow up clavicle?
1st presentation: AP shoulder
Follow up: AP clavicle
Both have an Axial clavicle
What is the angle for an axial clavicle?
15-30 degrees cephalad
What is in a scapula series?
AP shoulder, lateral shoulder
What is an AC joint series?
AP bilateral non-weight bearing
AP bilateral weight bearing
What is in a humerus series?
AP, lateral
What is the technique for a lateral humerus?
Patient is perpendicular to IP, and their elbow is extended posteriorly, with their hand on their abdomen
What are all the types of chest x-rays? (5)
- PA Chest
- Lateral
- AP supine chest (patient laying on back)
- Lateral decubitus (patient laying on their side)
- Lordotic (patient leans back)
What is the angle for a lordotic chest, when a patient cannot lean back?
15-20 degrees cephalad
Inhale or Exhale for a standard chest x-ray?
Inhale
What is the difference between a LPO and RAO?
RAO has the patient facing the buckey, LPO the patient faces the beam
What is the centre point for an AP lower ribs?
Midline between zyphoid and lower rib cage
Inspiration or expiration for an AP ribs?
Inspiration
Where should the bottom of the image plate be for an AP ribs?
Top of iliac crests
When do you do an LPO?
oblique ribs of one affected side
When do you do a RAO
RAO sternum, and RAO SCJ
For bilateral SCJ, an LAO is also required.
How much should the patient be rotated for a RAO
15 - 20 degrees
For a sternum RAO, which shoulder should always be on the image plate?
right shoulder because it decreases the likelihood of other structures superimposing the sternum
What is the centre point for a RAO sternum?
2.5cm left of the spine, mid sternum level
If you use the Moore method to take a RAO sternum, what degree should the x-ray tube be turned?
15-25 degrees
Where should the arms be for a lateral sternum?
Hands should be clasped behind the back, and shoulders pulled back to bring sternum out
What is the centre point for a PA SCJ?
T3, through midline
What is in a toe series?
Dorsal-Plantar (DP), oblique, lateral
What angle is used for a DP toe?
10 degrees cephalad
What is the centre point for a DP toe?
Metatarsal-phalangeal joint, first toe knuckle
What is the collimation for a DP and oblique toe?
Tight to toe, but include 1/2 the metatarsal
What direction should you rotate the knee for a DP toe?
internally rotate knee
What directions should you rotate the foot for a lateral toe?
Internal rotation: big toe (hallucis), 2nd and 3rd digits
External rotation: 3rd, 4th and 5th (digiti minimi) digits
What is the difference between an acute/ trauma foot x-ray series and a chronic one?
All chronic projections are done weight bearing (i.e. standing to bear own body weight)
What angle is used for a DP foot?
10 degrees cephalad
What is the centre point for an oblique and DP foot?
Base of 3rd metatarsal
Is the knee bent for a DP foot?
yes
Internal or external rotation of the knee for an oblique foot?
internal
Where is the other leg positioned for a lateral foot?
behind the leg in question to prevent rotation of foot in question
Is the foot dorsiflexed or plantarflexed for a lateral foot x-ray
dorsiflexed at 90 degrees
What is a sesamoid series for the foot?
DP, oblique, lateral foot + axial
physically show the position for a Axial (prone) foot and a axial (supine) foot
prone: foot upside down, toes on image plate, arch overdone to prevent the heel from accidentally being imaged
supine: foot right way up, heel on image plate, band used to pull toes out the way
What is the difference between a acute/ trauma ankle series and a chronic series?
The chronic series are all weight bearing (i.e. patient is standing so their own body weight acts as a weight)
What is in a ankle series
AP, oblique/ mortise, lateral
What is a mortise ankle?
x-ray to image ankle at a 45 degree angle.
It is done by putting the leg straight out, and then medially rotating the knee by 30 degrees
How much of the lower leg should you include in an ankle x-ray?
distal 1/3rd of the tibia and fibula
What is a calcaneus series?
Heel series, includes a lateral and axial
What is the centre point for a lateral calcaneum?
Mid-calcaneus, 2.5cm inferior to medial malleolus
How is the foot positioned for an axial calcaneus
Foot supine, heel on plate, dorsiflexion as much as possible
What angle is used for an axial calcaneus?
40 degrees down through the heel
What is in a Tib/Fib series?
AP and lateral
What is in an acute/ trauma knee series?
AP and horizontal ray lateral
What angle is the beam for an AP knee?
+- 5 degrees
What is the centre point for an AP knee
2.5cm distal to patella
What is the centre point for a lateral knee?
Midpoint of knee joint
What is in a chronic knee series?
AP Bilateral weight-bearing
Skyline bilateral
Intercondylar
Lateral
What is the midpoint for bilateral AP knees?
Performed standing, 1.5cm inferior/ below to patella
What angle should the knee be bent for bilateral skyline (axial) knee?
45 degree bend
What angle is the beam for a bilateral Skyline?
10-15 degrees uptilt (ceph)
what is the centre point for a skyline knee?
midway between patellae
Where does the image plate go for a skyline knee?
Patient hold it upright on their abdomen
What angle is the knee flexed at for a intercondylar knee
40-45 degrees
What angle should the beam be for an intercondylar knee?
40 - 45 degrees cephalad
Where does the image plate go for an intercondylar knee?
below the knees, preferably not in the table buckey
What is the centre point for an intercondylar knee?
1.5 cm inferior to patella apex
How much should the knee be flexed for a lateral knee?
20 - 30 degrees
What can you do to make the knee more lateral if the patient is too rotated?
rotate the opposite hip to affected knee anteriorly or posteriorly, depending on what is required
What is the central ray angle for a lateral knee?
5 degrees cephalad
Is the medial or lateral side facing up for a lateral knee?
medial side
What is the centre point for a lateral knee?
2.5cm distal to medial epicondyle
