Chapter 6 Toes- Foot: Image Analysis
Tha average lateral calcaneal projection demonstrates approximately __________ inches of the cuboid posterior to the navicular.
1/2
The average foot projection demonstrates approximately _____________ inches for the cuboid posterior to the navicular on a lateral foot.
1/2 (1.25 cm)
If the calcaneus is positioned too close to the IR and the forefoot is raised off the IR for a lateral calcaneal projection, the (A)___________ talar dome is demonstrated (B)___________ to the (C)____________ talar dome, and the fibula is demonstrated too far (D)_________ on the tibia.
2 possible answers A1) medial B2) posterior C3) lateral D4) anterior A2) lateral B2) anterior C2) medial D2) anterior
If the distal tibia is positioned farther from the imaging table than the proximal tibia for lateral calcaneal projection, the (A)___________ dome is demonstrated (B)______________ to the (C)__________ talar dome, and the medial longitudinal foot arch appears (D)_____________ (higher/lower) on the resulting projection.
2 possible answers A1) medial B2) proximal C3) lateral D4) higher A2) lateral B2) distal C2) medial D2) higher
On a lateral foot, if the calcaneus is positioned too close to the IR and the forefoot is raised off the IR for a lateral foot projection, the (A)_________ talar dome is demonstrated (B)___________ to the (C)_______ talar dome, and the fibula is demonstrated to far (D)______ on the tibia.
2 ways to answer A1) medial B1) Posterior C1) lateral D1) anterior A2) lateral B2) anterior C2) medial D2) anterior
If the distal tibia is positioned farther from the imaging table than the proximal tibia for a lateral foot projection, the (A)________(lateral/medial) dome is demonstrated (B)______________ to the (C)_____________(lateral/medial) talar dome and the medial foot arch appears (D)________(higher/lower) on the resulting projection on a lateral foot.
2 ways to answer A1) medial B1) Proximal C1) lateral D1) higher A2) lateral B2) distal C2) medial D2) higher
On a lateral foot, if the forefoot is positioned too close to the IR and the calcaneus is elevated off the IR for a lateral foot projection, the (A)_________ talar dome is demonstrated (B)_________ to the (C)_______ talar dome, and the fibula is demonstrated too far (D)_____ on the tibia.
2 ways to answer A1) medial B1) anterior C1) lateral D1) posterior A2) lateral B2) posterior C2) medial D2) posterior
If the proximal tibia is positioned farther from the imaging table than the distal tibia for a lateral foot projection, the (A)______ dome is demonstrated (B)__________ to the (C)________ talar dome, and the medial foot arch appears (D)_______________ (higher/lower) on the resulting projection on a lateral foot.
2 ways to answer A1) medial B1) distal C1) lateral D1) lower A2) lateral B2) proximal C2) medial D2) lower
Accurate CR centering on an axial calcaneal projection is accomplished by centering the CR to the midline of the foot at the level of the__________.
5th MT base
An (A)_____________ degree proximal CR angulation is required for an AP axial foot projection to demonstrate open TMT joint spaces. Is a higher degree angulation needed in a patient with low medial longitudinal arch or a high medial longitudinal arch? (B)________________
A) 10 - 15 degree B) High arch requires more CR angulation
What degree of patient to obliquity is used for an AP oblique toe projection? A)_____________________ How is the accuracy of the degree of toe obliquity identified on an AP oblique toe projection? (B)____________________
A) 45 degrees B) twice as much soft tissue width is present on the side of the digit rotated away from the IR when Accurate
The degree of foot obliquity needed for an AP oblique foot projection varies according to the height of the medial longitudinal arch. What degree of obliquity is used in a patient with a high medial longitudinal arch? A)____________ In a patient with a low medial longitudinal arch? B)______________ In a patient with an average medial longitudinal arch? C)___________
A) 60 degrees B) 30 degrees C) 45 degrees
State the kV range for the following projections: A) lateral ankle: B) Grid AP knee: C) AP femur:
A) 60 to 70 kV B) 70 to 85 kV C) 80 to 85 kV
AP Oblique Foot Projection. The (A)__________ and the (B)______________ intermetatarsal joint spaces are open. Tarsi sinus and (C)__________ metatarsal tuberosity are visualized. (D)____________ base is at the center of the exposure field.
A) Cuboid-cuneiform B) Third through fifth C) 5th D) 3rd MT
AP axial foot Joint space between the (A)____________ and (B)_______________ cuneiforms is open, and about (C)____________ of the talus is superimposed the calcaneus. (D)____________ and navicular-cuneiform joint spaces are open. (E)_____________ metatarsal base is at the center of the exposure field.
A) Medial (first) B) Intermediate (second) C) One third D) TMT E) Third
For an AP axial foot projection, equal pressure is places on the (A)_________ foot surface and the (B)___________, (C)________, and (D)______________ should remain aligned.
A) Plantar B) Lower leg C) ankle D) Foot
Lateral Foot Projection: Contrast and density are adequate to demonstrate the (A)_______ and (B)______ fat pads. Talar domes are superimposed, the (C)__________ joint is open, and the distal fibula is superimposed by the posterior half of the distal tibia. The long axis of the foot is positioned at a (D)_____________ angle with the lower leg. (E)___________ are at the center of the exposure field.
A) anterior pretalar B) posterior pericapsular C) tibiotalar D) 90-degree angle E) distal tarsals
As a foot is rotated medially from an AP projection the first MT base rotates (A)___________(over/beneath) the (B)___________ MT base and the second through 3rd MT heads move (C)__________ (closer to/ father from) one another.
A) beneath B) second C) closer to
Lateral Toe The (A)__________ of the proximal phalanx are superimposed. There is no (B)____________ or bony overlap from adjacent toes The (C)____________ joint is at the center of the exposure field.
A) condyles B) soft tissue C) IP for first toe and PIP for 2nd -5th toes
If an axial calcaneal projection is requested for a patient who is unable to dorsiflex the foot to a vertical position, how is the positioning setup adjusted before the projection is obtained? A)________________ How is the setup changed if the patient dorsiflexed the foot beyond the vertical position? B)_______________
A) increase the degree of CR angulation B) decrease the degree of CR angulation
On a lateral foot, why is it important to dorsiflex the foot to a 90-degree angle with the lower leg? A)_______________ B)________________ C)________________
A) it demonstrates the anterior pretalar fat pad without forces flattening. B) it places the tibiotalar joint in a neutral position. C) it prevents anterior foot rotation
IF the toe is medially rotated for right AP axial toe projection the (A)________ (medial/lateral) side of the toe demonstrates the greatest soft tissue width, and the (B)_________ side demonstrates the greatest phalangeal midshaft concavity.
A) lateral B) Lateral
Misalignment of the talar domes can be caused by poor (A)________ or (B)__________ positioning on a lateral foot
A) leg B) foot
In a patient with a low medial foot arch, (A)_________ (more,less) of the cuboid will be demonstrated posterior to the navicular, and in a patient with a high medial foot arch, (B)_________ (more/less) will be demonstrated on a lateral foot.
A) less B) more
Against which aspect of the foot is the IR placed for a standing lateromedial projection of the foot? A)________________ Which surface (medial/lateral) of the foot is aligned parallel with the IR for a lateromedial projection of the foot with accurate positioning? B)____________________
A) medial B) lateral
In what direction are the foot and toe rotated for a first through third AP oblique toe projection? (A)_____________________ For a forth through fifth AP oblique toe projection (B)___________________ Why are the patients foot and toe rotated differently for these exams? (C)______________________
A) medially B) Laterally C) to obtain an oblique using the least amount of OID
To position the toe is an lateral protection, the foot is rotated (A)___________ (medially/ laterally) when the first through thirds toes are imaged and (B)___________(medially/laterally) when the fourth and fifth toes are imaged.
A) medially B) laterally
To obtain open joint spaces on an AP axial toe projection, align the CR (A)_____________ to the joint space and align the joint space (B)_________ to the IR.
A) parallel B) perpendicular
When the CR and foot are accurately aligned, the CR is aligned (A)_________ to the talocalcaneal joint space and (B)_________ to the calcaneal tuberosity for a calcaneus prpjection.
A) parallel B) perpendicular
Accurate CR centering on a lateral foot projection is accomplished by centering an (A)_____ CR to the foot midline at the level of the (B)______________.
A) perpendicular B) 5th MT base
Accurate CR centering on a lateral calcaneal projection is accomplished by centering an (A)________ CR 1 inch (B)_________ to the (C)__________.
A) perpendicular B) distal C) medial malleolus
How is the patient positioned to prevent calcaneal tilting? A)__________ How is calcaneal titling identified on an axial calcaneal projection with poor positioning? B)_________
A) place the ankle in an AP projection without medial or lateral rotation. B) the 1st MT will be demonstrated medially, or the 4th & 5th MTs will be demonstrated laterrally.
How is the foot positioned with the lower leg and IR to obtain a lateral calcaneal projection with accurate positioning? A) lower leg: B) IR:
A) position the long axis of the foot at a 90-degree angle with the lower leg. B) position the lateral foot surface parallel with the IR.
How is the foot positoned with the lower leg and IR to obtain a lateral foot projection with accurate positioning? A) lower leg:____________ B) IR:______________
A) position the long axis of the foot at a 90-degree angle with the lower leg. B) position the lateral foot surface parallel with the IR.
The height of the medial longitudinal arch can be determined on a lateral foot projection with accurate positioning by measuring the amount of cuboid the appears A)____________ to the B)______________. On a lateral foot
A) posterior B) navicular
The height of the medial longitudinal arch is determined on a lateral calcaneal projection with accurate positioning by measuring the amount of cuboid that appears (A)____________ to the (B)_________.
A) posterior B) navicular
Lateral calcaneus projection The talar domes are superimposed, the tibiotalar joint space is open, and the distal fibula is superimposed by the (A)________ half of the distal tibia. The long axis of the foot is positioned at a 90-degree angle with the (B)___________. the (C)_________ is at the center of the exposure field.
A) posterior B) lower leg C) medcalcaneus
AP axial toe projection: The (A)_________ width and the midshaft (B)______________ are equal on both sides of the phalanges The (C)___________ and (D)____________ joints are open, and the phalanges are seen without foreshortening. The (E)_________ joint is at the center of the exposure field for a toe projection and (F)___________ MTP joint is at the center when all toes are imaged.
A) soft tissue B) concavity C) IP D) MTP E) IP for first toe and PIP for second-fifth toes F) third
Axial calcaneus projection The (A)__________ joint is open, and the calcaneal tuberosity is demonstrated with minimal distortion. The second through 4th distal MTs are not demonstrated on the (B)______or (C)_________ aspects of the foot, respectively. The (D)_______________ is at the center of the exposure field.
A) talocalcaneal B) medial C) lateral D) proximal calcaneal tuberosity
How do the following foot and lower leg positions affect the COG (center of gravity) and BOS (base of support) for a lateral foot projection: A) affected foot at an 85 degree angle with the lower leg when the unaffected foot is in front of the affected foot and 95 degree angle with the lower leg when the unaffected foot is back of the the affected foot:________________________ B) affected foot at a 100-degree angle with the lower leg and was obtained with the unaffected foot positioned too far behind the affected foot:_______________ C) affected foot is at a greater than 90-degree angle with the lower leg:________________________ D) affected foot is at a 75-degree angle with the lower leg and was taken with the unaffected foot positioned too far in front of the affected foot:____________________________
A) the COG is centered above the BOS center. B) The COG is centered behind the BOS center. C) The COG is centered behind the BOS D) The COG center is places in front of the BOS center
A lateral foot projection was requested for a patient with a large upper thigh that prevented the lower leg from aligning parallel with the imaging table when the patient was positioned. If the projection was obtained with the patient positioned in this manner, how would this poor positioning be identified on the resulting projection? A)________________________ How is the positioning setup adjusted in this situation before the projection is obtained? B)____________
A) the medial talar dome would be demonstrated distal to the lateral talar dome. B) elevate the distal lower leg and ankle until the lower leg is parallel with the imaging table.
List 2 soft tissue fat pads that should be demonstrated on a lateral foot projection, and describe their locations. A)_____________ B)_____________
A) the posterior pericapsular located within indention formed by the articulation of the posterior tibia and talar bone B) anterior pretalar located anterior to the ankle joint, next to the talus
AP oblique toe (A)__________ as much soft tissue width and phalangeal and metatarsal concavity are present on the side of the digit rotated (B)____________ the IR. The (C)_____________ and (D)____________ joints are open, and the phalanges are demonstrated without foreshortening. (E)____________ joint is at the center of the exposure field for a toe projection and the third MTP joint is at the center when all toes are imaged.
A) twice B) Away from C) IP D) MTP E) IP for first toe and PIP for 2nd-5th toes
To obtain an axial calcaneal projection with accurate positioning, position the foot (A)_______ and direct a (B)___________-degree proximal CR angulation toward the (C)____________ foot surface
A) vertical B) 40 C) plantar
Dorsiflex
Act of moving toes and forefoot upwards
Which anatomic structures can be used to estimate the CR angulation needed when the patient is unable to dorsiflex the foot into a vertical position?
Base of the 5th MT and distal point of the fibula
The patient was unable to fully extend the toe for an AP oblique toe projection. What will the resulting projection demonstrate if a perpendicular CR was used for this patient?
Closed joint space and foreshortened phalanges
Which surface of the foot is positioned against the IR for a mediolateral projection of the foot?
Lateral
Will medial or lateral foot rotation result in increased superimposition of the MT bases?
Lateral
Intermalleolar line
Line connecting medial and lateral malleoli
Abductor tubercle
Located posteriorly on medial femoral condyle
Will medial or lateral foot rotation result in the talus moving away from the calcaneous?
Medial
An AP oblique foot projection is obtained by rotating the patient 30 to 60 degrees_________(medialy/lateraly).
Medially
Which anatomic structures are included on an AP axial foot projection with accurate positioning?
Proximal calcaneus, talar neckm tarsals, MTs, phalanges, and surrounding soft tissue
The actual height of the medial foot arch on a lateral foot projection is accurate only when the _________ are superimposed.
Talar domes
When the foot is medially rotated more than needed for an AP oblique foot projection with accurate positioning, will the fourth MT tubercle be superimposed over the 5th MT or will the 5th MT be superimposed over the the 4th MT?
The 5th MT will be superimposed over the fourth MT tubercle
Soft tissue and bony overlap of unaffected digit onto the affected digit is present. For the Lateral toe, how was this patient miss positioned?
The adjacent unaffected digits
On a lateral foot projection the tibiotalar joint space is obscured, one talar dome is demonstrated proximal to the other dome, and more than 0.5 inch (1.25 cm) of the cuboid appears posterior to the navicular. How was the patient miss positioned?
The distal lower leg was elevated higher than the proximal lower leg.
The phalanges demonstrate more soft tissue width on the medial toe surface than the lateral surface. For the AP axial toe, how was this patient miss positioned?
The foot and toe were laterally rotated
The proximal phalanx demonstrates nearly equal midshaft concavity and the MT heads are demonstrated posterior to the first toe. For the Lateral toe, how was this patient miss positioned?
The foot and toe were not rotated enough to place the toe in a lateral projection
The condyles of the proximal phalanx are shown without superimposition and the MT heads are superimposed. For the Lateral toe, how was this patient miss positioned?
The foot and toe were rotated too much to place the toe in a lateral projection
The joint space between the medial and intermediate cuneiforms is closed, the navicular is demonstrated in profile, and more than one-third of the talus superimposes the calcaneus. For the AP axial foot, how was this patient miss positioned?
The foot was laterally rotated
The lateral cuneiform-cuboid, navicular-cuboid, and intermetatarsal joint spaces are closed, and the 5th MT is superimposed over the 4th MT tubercle. For an AP oblique projection, how was the patient miss positioned?
The foot was overrotated
The lateral cuneiform-cuboid, navicular-cuboid, and 3rd through 5th intermetatarsal spaces are closed, and the 4th MT tubercle is demonstrated without 5th superimposition. For an AP oblique projection, how was the patient miss positioned?
The foot was underrotated.
On an axial calcaneus projection, the 4th and 5th MTs are demonstrated laterally. How was the patient miss positioned?
The leg and ankle were laterally rotated.
Which anatomic structures are included on an AP axial toe projection with accurate positioning?
The phalanges and half of the MT
Which anatomic structures are included on an AP oblique toe projection with accurate positioning?
The phalanges and half of the metatarsal
which anatomic structures are included on a lateral toe projection with accurate positioning?
The phalanges and the MTP joint space
Which anatomic structures are demonstrated within the collimated field on an AP oblique foot projection with accurate positioning?
The phalanges, MT, Tarals, calanceus, and surrounding soft tissue.
Which anatomic structures are included on a lateral foot projection with accurate positioning?
The phalanges, MTs, tarsals, talus, calcaneus, 1" (2.5 cm) of the distal lower leg, and the surrounding foot soft tissue.
On a lateral foot projection the tibiotalar joint space is obscured, one talar dome is demonstrated proximal to the other dome, and the navicular is superimposed over most of the cuboid. How was the patient miss positioned?
The proximal lower leg was elevated higher than the distal lower leg.
On a lateral calcaneal projection, the tibiotalar joint space is obscured, one talar dome is demonstrated proximal to the other, and the navicular bone is superimposed over most of the cuboid. How was the patient miss positioned?
The proximal tibia was elevated.
The soft tissue width demonstrated on each side of the phalanges is nearly equal. For the AP oblique toe, how was this patient miss positioned?
The toe and foot were close to an AP projection
The IP and MTP joint spaces are closed, and the phalanges are foreshortened. For the AP axial toe, how was this patient miss positioned?
The toe was flexed
lateral mortise
Tibiofibular joint
Plantar flexion
act of moving toes and forefoot downward
If a lateral foot projection with poor positioning demonstrates an obscured tibiotalar joint space, on talar dome proximal to the other, and the navicular superimposed over most of the cuboid, which dome is proximal?
lateral
Valgus deformity
lateral side of knee joint is narrower
Varus deformity
medial side of knee joint narrower
If a standing lateromedial projection of the foot with poor positioning demonstrates one talar dome and the fibula is situated too far posterior on the tibia, how should the patients position be adjusted for an optimal projection to be obtained?
move the patient's heel away from the IR
Why is it important to not have soft tissue overlap on an AP oblique toe projection?
obscures the soft tissue detail
Tarsi sinus
opening between the calcaneus and talus
How is the lower leg positioned to obtain a lateral calcaneal projection with accurate positioning?
parallel with the IR
Subluxation
partial dislocation
How is the lower leg placed to obtain a lateral foot projectionf with accurate positioning.
position the lower leg parallel with the IR
plantar
sole of foot
The TMT and navicular-cuneiform joint spaces are obscured. For the AP axial foot, how was the patient miss poisitioned?
the CR was not angled enough proximally
On a weight-bearing AP foot, the CR angulation needed may be less than what is needed for a nonweight-bearing AP foot. Why?
the added body weight will flatten the medial arch, causing the TMT joints to be at a lower angle with the IR
Which anatomic structures are included on an axial calcaneal projection with accurate positioning?
the calcaneal tuberosity and talocalcaneal joint
On an axial calcaneus projection the talocalcaneal joint space is obscured, and the calcaneal tuberosity is foreshortened. the standard 40-degree angulation was used. How was the patient miss positioned?
the foot was in plantarflexion
The joint space between the medial and intermediate cuneiforms is closed, the calcaneus is demonstrated without talar superimposition, and the MT bases demonstrate decreases superimposition. For the AP axial foot, how was this patient miss positioned?
the foot was medially rotated
On a lateral calcaneus, the tibiotalar joint space is obscured, one talar dome is demonstrated anterior to the other dome, and the fibula is demonstrated too posterior on the tibia. how is the patient miss positioned?
the forefoot was depressed, and the heel was elevated (leg externally rotated)
On a lateral foot projection the tibiotalar joint is obscured, one talar dome is demonstrated anterior to the other dome, and the fibula is demonstrated too anterior on the tibia. How was the patient miss positioned?
the heel was depressed, and the forefoot was elevated.
On a lateral foot projection the tibiotalar joint is obscured , on talar dome is demonstrated anterior to the other dome, and the fibula is demonstrated too posterior on the tibia. How was the patient miss positioned?
the heel was elevated, and the forefoot was depressed
On an axial calcaneus projection, the 1sr MT is demonstrated medially. How was the patient miss positioned?
the leg and ankle were medially rotated.
A calcaneal foot projection was requested for a patient with a large upper thigh that prevented the lower leg from aligning parallel with the imaging table when the patient was positioned. If the projection was obtained with the patient positioned in this manner, how would this poor positioning be identified on the resulting projection?
the medial talar dome would be demonstrated distal to the lateral talar dome.
Which anatomic structures are included on a lateral calcaneal projection with accurate positioning?
the tibiotalar joint, talas, calcaneus, and calcaneal articulating tarsal bones.
The proximal phalanx demonstrates more concavity on the posterior aspect than the anterior aspect. For the AP oblique toe, how was this patient miss positioned?
the toe was close to a lateral projection
The IP and MTP joints spaces are obscured and the phalanges are foreshortened. For the AP oblique toe, how was this patient miss positioned?
the toe was flexed, and the CR was not angled perpendicular to the phalanges or parallel with the joint spaces
Why are weight-bearing projections of the foot obtained?
to demonstrate how the body parts react when the patients body weight is acted upon it.