Advanced Skeletal Flashcards
Inferosuperior Tangential Wrist: Clinical Indications
abnormal calcifications and bony changes in the carpal sulcus that may impinge on the median nerve; carpal tunnel syndrome. Possible fractures of the hamulus process, pisiform and trapezium
Inferosuperior tangential wrist: Technical factors
SID: 40inches
IR: 8X10; non grid
Exposure factors: 60kV and 4-5mAs
Inferosuperior tangential wrist: positioning and central ray
Position: patient seated at the end of the table. Hand aligned with the long axis of IR. Hyperextend hand (dorsiflex wrist) so that the metacarpals are perpendicular (90 degrees) to the IR without lifting the forearm or wrist. Internally rotate (radially) the hand 10 degrees.
CR: angled 25-30 degrees to the long axis of the hand. Directed 1 inch distal to the base of the third metacarpal (center of hand).
Inferosuperior tangential wrist: evaluation criteria
Anatomy:
- the carpals are demonstrated in a tunnel-like, arched arrangement.
Position:
- the pisiform and the hamulus should be separated and visible in profile without superimposition.
- The rounded palmar aspects of the capitate and the scaphoid should be visualized in profile as well as the aspect of the trapezium that articulates with the first metacarpal
- CR and center of collimation to the midpoint of the carpal canal
Exposure:
- optimal density (brightness) and contrast as indicated by visualization of soft tissues and possible calcifications in carpal canal regian and outlines of the superimposed carpals are visable without overexposure of the carpals in profile.
- no motion as indicated by trabecular markings appearing sharp and clear
inferosuperior tangential wrist: adaption
If the patient is unable to dorsiflex wrist to place metacarpals perpendicular (90 degrees to the IR.
- align CR parallel to the long axis of the patient’s palm
- increase the angle 15 degrees from there
Clinical indication: Carpal Tunnel Syndrome
Symptoms -Numbness in 2 or more fingers -Pain that can extend to the elbow -Tingling or burning -Unable to tell the difference between hot and cold -Difficulty gripping small objects Treatment -Medication and or bracing -Ergonomics - surgery
Acute flexion elbow: clinical indications
Fractures and moderate dislocations of the elbow in acute flexion when the elbow cannot be extended to any degree
Acute flexion elbow: technical factors
SID:
40inches
IR:
10X12; landscape (2 exposures) ; nongrid
Exposure factors:
kV: 60 for distal humerus, 65 for proximal forearm
4-6mAs
Acute flexion elbow: positioning and Central ray
positioning
- patient seated with acutely flexed eblow resting on IR and the patients fingertips resting on their shoulder. Align and center humerus to the long axis of the IR. Center the elbow joint region. palpate humeral epicondyles and ensure they are parallel to the IR (no rotation).
Central Ray
- distal humerus: perpendicular to IR and humerus, directed midway between the epicondyles
-proximal forearm: perpendicular to the forearm (angle as needed). directed 2 inches proximal (superior) to the olecranon process
Acute flexion elbow: evaluation criteria
four sided collimation borders should be visable with CR and center of collimation field between epicondyles
Distal humerus
- forearm and humerus directly sumerimposed
- medial and lateral epicondyles and parts of trochlea, capitulum and olecrannon process are seen in profile
- optimal exposure should visualize distal humerus and olecrannon process through superimposed structures
- soft tissue detail is not readily visable
Proximal forearm
- proximal ulna and radius, including radial head and neck should be viable through the superimposed distal humerus
- optimal exposure visualizes outlines of proximal ulna and radisu superimposed over humerus
- soft tissue detail not readily availble
Acute flexion study MUST include both projections unless otherwise specified
Oblique elbow: Clinical Indications
- Fractures and dislocations of the elbow,
primarily the radial head and neck
-Certain pathologic processes, such as
osteomyelitis and arthritis
-Lateral (External Rotation) Oblique Best
visualizes radial head and neck of the radius and capitulum of humerus
-Medial (Internal Rotation) Oblique Best
visualizes coronoid process of ulna and
trochlea in profile
Oblque elbow: technical factors
SID:
40inches
IR:
10X12in ; landscape (two exposures) ; nongrid
Exposure factors
60 kV
3.2-5 mAs
Internal Oblique elbow: position and central ray
Patient seated with arm fully extended with elbow and shoulder on the same horizontal plane
Align arm and forearm with long axis of IR
Medial (internal) rotation
- pronate hand
- rotate arm until distal humerus and elbow are rotated 45 degrees. the interepicondylar line is approximately 45 degrees to the IR (this should be achieved by simply pronating the hand)
CR
perpendicular to IR directed 3/4th of an inch distal to interepicondylar line
External Oblique elbow: positioning and CR
Patient seated with arm fully extended with elbow and shoulder on the same horizontal plane
Align arm and forearm with long axis of IR
Lateral (external rotation
- supinate hand and roate entire arm laterally so that the distal humerus and the anterior surface of the elbow joint are approximately 45 degrees to the IR (this can be achieved by leaning laterally so that the patient shoulder is is resting on the table)
Central ray (both medial and lateral obliques)
- perpendicular to IR
- directed approximately 2cm distal to the midpoint between the humeral epicondyles
Medial Oblique elbows: Evaluation Criteria
Anatomy
-Oblique view of distal humerus
and proximal radius and ulna is visible.
Position
- Long axis of arm should be aligned with side
border o IR.
-Correct 45° medial oblique should visualize
coronoid process of the ulna in profile.
-Radial head and neck should be superimposed and centered over the proximal
ulna.
- Medial epicondyle and trochlea should appear
elongated and in partial profile.
-Olecranon process should
appear seated in olecranon fossa and trochlear notch partially
open and visualized with arm fully extended.
-CR and center
of collimation field should be at mid-elbow joint.
Exposure:
-Optimal density (brightness) and contrast with
no motion should visualize soft tissue detail; bony cortical
margins; and clear, bony trabecular markings
External (lateral) oblique elbow: evaluation criteria
Anatomy
- Oblique projection of distal
humerus and proximal radius and ulna is visible
Position
-Long axis of arm should be aligned with side
border of IR.
- correct 45-degree oblique evident by visualization of radial head, neck and tuberosity, free of superimposition by ulna
-lateral epicondyle and capitulum should appear elongated and in profile
- CR and center of collimation should be to mid-elbow joint
Exposure
- Optimal density (brightness) and contrast with
no motion should visualize soft tissue detail; sharp, bony
cortical margins; and clear, bony trabecular markings
Radial Head lateral (4 views) : Clinical indications
fractures of radial head and neck
Radial Head laterals: technical factors
SID:
40inches
IR:
10X12in ; landscape (all four projections); nongrid
exposure factors:
60kV
3.2-6 mAs
Radial head laterals: position and CR
Center radial head to IR so that humerus and proximal forearm are parallel with IR borders.
4 projections:
-1. supinate hand (palm up) and externally rotate as far as the patient can tolerate
-2. place hand in true lateral position (thumb up)
-3. pronate hand (palm down)
-4. internally rotate hand (thumb down ) as far as patient can tolerate
CR
perpendicular to IR, directed to the radial head (approximately 1 inch distal to lateral epicondyle)
Radial head laterals: evaluation criteria
- Elbow should be flexed 90° in true lateral position, as
evidenced by direct superimposition o epicondyles
-radial head and neck should be partially superimposed by ulna but completely visualized in profile in various projections
-radial tuberosity should be visualized in various positions as follows from external to internal rotation of the hand:
1. slightly anterior
2. superimposed over radial shaft
3. slightly posterior
4. most posterior, seen adjacent to the ulna
Optimal exposure with no motion should clearly
visualize sharp, bony margins and clear trabecular markings of
radial head and neck area
Fat Pad signs
Indication of synovial effusion, bursal hemorrhage or fracture
Elbow
Anterior pad is normally slightly visible in lateral view
Posterior pad is not normally illustrated
With trauma the anterior pad is more rounded and pronounced and the posterior pad is visible
‘Sail’ sign
Other joints: hip, wrist & ankle
Weight-bearing foot: clinical indications
- Demonstrates the position of the bones of the feet under full body weight
- Shows the longitudinal arches
- Joint fusions
- Pathology i.e. arthritis
weight-bearing foot: technical factors
SID:
40in
IR:
10X12 in for unilateral, 14X17 in for bilateral study; landscape; non-grid
Exposure factors:
60kV; 3.2-4mAs
weight-bearing foot AP: positioning and CR
Place patient erect, with full weight evenly distributed on both
feet.
Feet should be directed straight ahead, parallel to each other
Central ray
Angle CR 15° posteriorly to the midpoint between feet at the level of
base of metatarsals
Weight-bearing foot Lateral: positioning and central ray
The patient is standing on a solid platform with a cassette lower than the soles of the feet
May have a special box with a slot for the cassette
Weight should be equally distributed between feet one on either side of the cassette
Both feet are imaged for comparison
typically done lateromedial (as described above)
CR:
perpendicular to the level of the base of the 3rd metatarsals
Weight-bearing foot AP: Evaluation Criteria
Anatomy Demonstrated:
-shows bilateral feet from soft tissue surrounding phalanges to distal portion of
talus.
Position:
-For AP, proper angulation is demonstrated by
open tarsometatarsal joint spaces and visualization of joint
between first and second cuneiforms.
- Metatarsal bases
should be at center of the collimated field (CR) with four-sided collimation, including the soft tissue surrounding the feet
Exposure:
-Optimal density (brightness) and contrast should
visualize soft tissue and bony borders of superimposed tarsals
and metatarsals.
- Adequate penetration of midfoot
region.
-Bony trabecular markings should be sharp
Weight-bearing foot Lateral: Evaluation Criteria
Anatomy Demonstrated:
- For lateral, entire foot should be
demonstrated, along with a minimum of 1 inch (2.5 cm) of distal tibia- fibula.
- Distal fibula should be seen superimposed over posterior half of the tibia, and plantar surfaces of heads of metatarsals should be superimposed if no rotation is present.
-The longitudinal arch of the foot must be
demonstrated in its entirety.
Position:
- For lateral, center of collimated field (CR) should be to level of base of third metatarsal.
-Four-sided
collimation should include all surrounding soft tissue from the phalanges to the calcaneus and from the dorsum to the
plantar surface of the foot with approximately 1 inch (2.5 cm)
of the distal tibia- fibula demonstrated.
Exposure:
- Optimal density (brightness) and contrast should visualize borders of superimposed tarsals and metatarsals.
- No motion; cortical margins and trabecular markings of calcaneus and nonsuperimposed portions of other tarsals should appear sharply defined
Ankle stress views Inversion/eversion : Clinical Indications
Pathology involving ankle joint separation
secondary to ligament tear or rupture
Ankle Stress views Inversion/eversion: technical factors
SID:
40inches
IR:
10X12in; portrait; nongrid
Exposure factors:
60kV; 2.5-3.2 mAs
Ankle stress views: Inversion/Eversion:
positioning and Central ray
Position
- Center and align ankle joint to CR and to long axis of portion of IR being exposed.
-Dorsiflex the foot as near the right angle to the lower leg as
possible.
-Stress is applied with leg and ankle in position for a true AP with no rotation, wherein the entire plantar surface is turned
-medially for inversion
-laterally for eversion
* This is done by a physician or an orthopedic technologist
CR
- perpendicular to the IR and directed to the midpoint of the malleoli
Ankle stress views: Evaluation criteria
Anatomy Demonstrated and Position:
-Ankle joint for evaluation of joint separation and ligament tear or rupture is
shown.
-Appearance of joint space may vary greatly
depending on the severity of ligament damage (if there is a ligamental injury present there will be an opening of the joint space)
- Collimation to the area of interest
Exposure:
- no motion as evident by the sharp bony margins and trabecular patterns
- Optimal exposure should
visualize soft tissue, lateral and medial malleoli, talus, and distal tibia and fibula
Oblique Knees: Clinical Indications
Fractures
Bony lesions
Degenerative changes
Oblique Knees: Technical Factors
SID:
40inches
IR:
10X12inches; portrait; nongrid
Technical Factors:
70kV; 5 mAs
Oblique Knees Medial (Internal) rotation: Position and Central Ray
Position
- patient is supine with the leg completely outstretched.
- the leg is internally rotated 45 degrees
CR:
-centred 1/2 inch below the apex of the patella
-for patients with an ASIS to table measurement of:
less than 19cm a 3-5 degree caudal angle is applied
for 19cm-24cm there is no angle
greater than 24cm a 3-5 degree cephalic angle
Oblique Lateral (external) rotation: Position and Central ray
positon:
- patient is supine with leg outstretched
- entire leg is externally rotated 45 degrees
CR:
-centred 1/2 inch below the apex of the patella
-for patients with an ASIS to table measurement of:
less than 19cm a 3-5 degree caudal angle is applied
for 19cm-24cm there is no angle
greater than 24cm a 3-5 degree cephalic angle
Oblique Knees Medial (internal) rotation: evaluation criteria
Anatomy Demonstrated:
-Distal femur and proximal tibia
and fibula with the patella superimposing the medial femoral condyle are shown.
-Lateral condyles of the femur and tibia
are well demonstrated, and the medial and lateral knee joint spaces appear unequal
Position:
- The proper amount of part obliquity demonstrates the proximal tibiofibular articulation open with the lateral condyles of the femur and tibia seen in profile.
- The head and neck of the fibula are visualized without superimposition, and approximately half of the patella should be seen free of superimposition by the femur. The center of the collimated field is to the femorotibial (knee) joint space.
Exposure:
-Optimal exposure with no motion should
visualize soft tissue in the knee joint area, and trabecular
markings of all bones should appear clear and sharp.
- Head and neck area of fibula should not appear overexposed
Oblique Knees Lateral (external rotation): Evaluation criteria
Anatomy Demonstrated:
-Distal femur and proximal tibia and fibula, with the patella superimposing the lateral femoral condyle, are shown.
-Medial condyles of the femur and tibia
are demonstrated in profile
Position:
- The proper amount of part obliquity demonstrates the proximal fibula superimposed by the proximal tibia, the medial condyles of the femur, and the tibia seen in profile.
- Approximately half of patella should be seen free of superimposition by the femur.
- Femorotibial (knee) joint space is the center of the collimated field.
Exposure:
- Optimal exposure should visualize soft tissue in the knee joint area and trabecular markings of all bones should
appear clear and sharp, indicating no motion.
-Technique should be sufficient to demonstrate the head and neck area
of the fibula through the superimposed tibia
Advanced Knee intercondylar fossa: Clinical Indications
- Loose/foreign bodies
- joint ‘mice’ ( fragments of bone that “float around in the knee cavity)
- Congenital slipped patella
- Osteochondritis dissecans
intercondylar fossa: Technical factors
SID:
40inch
IR:
8X10inch (unilateral) or 14X17 (bilateral); portrait; nongrid
Exposure factors
70kV; 4-6 mAs
intercondylar fossa: Holmblad method (PA)
- patient kneeling
-IR placed against anterior knee and shin
-Knee flexed 20 – 30 degrees so the femur forms an angle of 60 – 70 degrees with IR
-CR perpendicular to IR
Centre to midpopliteal crease
intercondylar fossa: Camp coventry method (PA)
-Pt. in prone position
-Femur in contact with the IR
-Knee flexed 40 or 50 degrees with foot supported
-CR perpendicular to long axis of tib/fib
-40 or 50 caudad angle
Centre at the knee joint (popiteal crease)
intercondylar fossa; rosenburg method (PA)
- weight-bearing
- evaulates joint space narrowing and articular cartelidge diease
- Bilateral standing with flexion
- Pt. stands facing upright bucky
- Flex knees so femurs are at an angle of 45 degrees with IR
- Have pt. hold on to the bucky for support
- center to 1/2 in below the patella, CR angled 10 degrees caudal
Intercondylar fossa: Béclere Method (AP)
- Pt. supine, place support under knee
- Cassette placed in between support and knee
- Knee flexed 40 – 45 degrees
- CR perpendicular to lower leg (40– 45 degrees)
- Centre 1.25 cm distal to apex of patella
Intercondylar Fossa: Evaluation Criteria
- Proximal surface of fossa in profile
- ICF not superimposed by patella
- Tibial plateau visable
- Open knee joint
- No rotation
Sternoclavicular (SC) joints: Clincal Indications
pathologies involving the SC joints, dislocations or fractures
PA SC joints: Technical factors
SID:
40inches
IR:
8X10inches; landscape; nongrid
Exposure Factors:
70kV; 12-16 mAs
PA SC joints positioning and central ray
Positioning
Have patient face IR. Erect or recumbent with arms at sides
CR
Directed to level of jugular notch (T2/T3)
PA SC joints: evaluation criteria
- SC joints and medial ends of clavicles seen without rotation as demonstrated by equal distance of sternoclavicular joints from vertebral column on both sides
-Lateral aspect of manubrium and
medial portion o the clavicles visualized lateral to the vertebral column through superimposing ribs and lungs. - no motion
Oblique SC joints: positioning and central ray
Position
Patient can be prone or erect (facing IR)
-Rotate pt. 10 – 15 degrees
*Note: both joints must be imaged for comparison
-Exposure on held expiration
CR
Directed to level of T2/T3 and 3-5cm laterally on raised side
*downside is imaged
Oblique SC joints: Evaluation criteria
Anatomy
The manubrium, medial portion of
clavicles and sternoclavicular joint are best demonstrated on the downside. The SC joint on the upside will be foreshortened.
Position:
- Correct patient rotation demonstrates the
downside sternoclavicular joint visualized with no superimposition of the vertebral column or manubrium.
Oblique SC joints: tube shift method
Patient is prone
-Angle tube 15 degrees towards spine
-Centre at T2/T3 and 3 – 5 cm lateral to spine to
exit opposite SC joint
Lumbar spine Flexion/extension: clinical indications
Recheck spinal fusion
Lumbar spine flexion/extension: technical factors
SID
40 inches
IR:
14X17; portrait (landscape if significant flexion); grid
Exposure factors:
90kV; 50 mAs
L spine flexion/extension positioning and CR
Positioning
Flexion
- Keep pelvis in same position and have pt. bend forward or move into fetal position
Extension
-Keep the pelvis in the same position and have pt. bend backward extending their head, shoulders and torso as much as possible
CR
perpendicular to IR (unless the pt. has a wide pelvis than a 5-8 degree caudal angle may be needed); directed to the iliac crest or fusion site if known
L spine flexion/extension: evaluation criteria
-no rotation is indicated by superimposed greater sciatic notches and posterior vertebral
bodies.
-Correctly marked as flexion or extension
-Intervertebral foramina L1-L4, vertebral bodies, intervertebral joints, spinous processes, and L5-S1 junction
Lumbar spine Obliques: clinical indications
Defects of the pars interarticularis (e.g.,
spondylolysis)
both sides imaged
L-spine obliques: technical factors
SID:
40inches
IR:
14X17in ; portrait; grid
Exposure factors
80kV; 20 mAs
L-spine Obliques: positioning and CR
positioning
- pt. is recumbent or erect
- breathing is suspended on expiration
Posterior
- Rotate the pt. 45 degrees
- Both sides will be imaged
- side down is visualized
CR
Centre at L3 (4 cm above crest) and 5 cm medial to raised ASIS
Anterior Obliques -Rotate the pt. 45 degrees -Both sides will be imaged -Upside is visualized CR Centre at L3 (4 cm above crest) and 5 cm Lateral to raised spinous process
L- spine Obliques: Evaluation criteria
Anatomy:
-Visualization of zygapophyseal
joints (RPO and LPO show downside; RAO and LAO show
upside).
Position:
- Accurate 45° patient rotation as indicated by open zygapophyseal joints and the pedicle (eye of the Scottie dog) between the midline and lateral aspect of the vertebral
border.
- If the pedicle is demonstrated closer to the midline
of the vertebral border and less of the pedicle is seen, this
indicates over-rotation. If the pedicle is demonstrated laterally
on the vertebral body border with more of the lamina (body
of Scottie dog) demonstrated, this indicates under-rotation.
Exposure:
-no motion, clear bony margins and trabecular marking
