Wrist and Forearm Positioning

when do we not use ulnar deviation

With severe pain, hand is not everted

in a PA wrist projection what is located vertically next to the radius?

Fat Stripe

where is the cr in inferosuperior position

central ray angled 25º-30º to long axis of hand

A radiograph of the PA scaphoid projection in ulnar flexion reveals extensive superimposition of the scaphoid and adjacent carpals

Insufficient ulnar flexion can lead to this problem.

describe a power grip PA projection

hand everted and clinched in a fist; CR is 90º (perpendicular) to IR

patient position for power grip projection

hand everted and clinched in a fist; CR is 90º (perpendicular) to IR

Patient position for wrist

90* angle from Ir shoulder, elbow and wrist in the same plane

what does the AP wrist projection demonstrate

AP projection best demonstrates the carpal interspaces.

A patient enters the ER with a possible scaphoid fracture. The patient is unable to assume the ulnar flexion position

modified stecher position with the CR angled 20° toward the elbow could be performed to confirm a scaphoid fracture

structures shown for wrist projection

Carpals, distal radius and ulna, and proximal metacarpals

how is the cr in superoinferior projection

CR is 90º to IR

A radiograph of a tangential, inferosuperior projection of the carpal canal reveal that the hamate is superimposed over the pisiform

Repeat the exposure rotating the wrist and hand 10° internally

What on the scaphoid should be demonstrated in a PA wrist oblique

tuberosity of the scaphoid should be demonstrated.

describe the humerus in a lateral forearm

- Distal humerus is in a lateral position

how should the radius and ulna be in a lateral wrist

The radius and ulna should be superimposed.

In a AP forearm, the radius and ulna should not be___________

The radius and ulna should not be superimposed distally

in a lateral wrist, where the ulnar styloid be seen

The ulnar styloid should be demonstrated in profile posteriorly

where is the CR angled in the carpal bridge/ tangenital projection

- CR angled 45º to long axis of forearm ;1 ½ " proximal to wrist joint

what are the structures shown in a carpal bridge projection

- Carpal bridge - Fractures of the scaphoid and dorsal aspect - Chip fractures, calcifications of dorsal carpal, and foreign bodies on dorsum of carpals bones

what does the gaynor hart method projection show?

- Carpal canal (tunnel) in arched arrangement - Entire pisiform in profile - "Hook" (hamular process) of hamate - Calcifications in carpal sulcus (groove)

what structures are shown in a radial flexion projection

- Carpal interspaces on the ulnar (medial) side of wrist

structures shown in a ap oblique wrist

- Carpals - Pisiform seen in profile, free of superimposition

what are the structures shown in a oblique PA wrist projection

- Carpals on lateral (radial) side of wrist, particularly the scaphoid (navicular) and trapezium

structures shown in a lateral wrist

- Carpals, proximal metacarpals, and distal radius and ulna superimposed - Anterior displacement (Smith) and posterior displacement (Colles) of fractures of radius

where is the central ray for ulnar deviation

- Centered to scaphoid - PA: 90° to IR

what part of the humerus should be in profile for a ap forearm projection

- Epicondyles of the humerus should be seen in profile

how do you perform a modified method of a carpal bridge/ tangenital projection

- Forearm elevated on support device; wrist flexed to right angle; IR placed vertically against back of hand

what structures are shown in a ap forearm

- Forearm including both elbow and wrist joints

PA oblique part position?

- From pronated position, rotate wrist laterally to form 45º angle with IR - Wrist in semipronation

Part position for wrist

- Hand pronated; fingers arched - Midcarpal area centered to IR

describe the humeral epicondyles in a lateral forearm projection

- Humeral epicondyles should be superimposed and perpendicular to the IR.

central ray for wrist

- Perpendicular to midcarpal area

how is the central ray in a AP oblique wrist

- Perpendicular to midcarpal area

where should the central ray be for a lateral forearm

- Perpendicular to midpoint of forearm

where is the central ray in a ap forearm

- Perpendicular to midpoint of forearm

what parts of the hand are shown in a ulnar deviation projection

- Scaphoid not foreshortened; opens carpal interspaces on radial (lateral) side of wrist

patient position for a ap forearm

- Seated - Entire upper extremity in same plane

patient position in a lateral wrist

- Seated, elbow flexed 90° - Entire upper limb in same plane

PA Oblique patient position?

- Seated, elbow flexed 90° - Hand and forearm resting palm down

smiths fracture of radius

Anterior displacement

what is the part position for a lateral forearm

Elbow flexed 90º; forearm centered to IR - Hand and wrist in lateral position - Distal radius and ulna superimposed - Humeral epicondyles superimposed

what structures should be shown in a lateral forearm

Forearm including both elbow and wrist joints

part position for AP oblique wrist

From supine position, rotate wrist medially to form a 45º angle with IR - Wrist in semisupination

what is a variation in the modified stecher method

Hand everted in ulnar flexion; elevated 20° on sponge; CR 90º (perpendicular) to IR

part position for a ap forearm

Hand in supination; patient leans laterally - Centered to midpoint of forearm - Humeral epicondyles parallel to IR

what is part position for ulnar deviation

Hand pronated - Evert hand (turn outward), flexed toward ulna

part position for radial flexion

Hand pronated - Invert hand (turn inward), flexed toward radius

Where is the central ray in a oblique wrist projection

Perpendicular to midcarpal area

where is the central ray in a lateral wrist

Perpendicular to midcarpal area

where is the central ray in a radial flexion projection

Perpendicular to midcarpal area

what is patient position for ulnar deviation

Seated - Entire upper limb in same plane

patient position for AP oblique wrist

Seated - Forearm in supine position

patient position for radial flexion projection

Seated, elbow flexed 90° - Entire upper limb in same plane

anteriorly, __________ should be seen in a lateral wrist

The anterior (pronator) fat stripe should be seen.

how should the sacphoind and pisiform be in a lateral wrist

The distal end of the scaphoid and the pisiform should be superimposed

how should the radius and ulna be in a lateral forearm

The distal radius and ulna should be superimposed.

what joint space should be open in a lateral forearm projection

The elbow joint space should be open, and the head of the radius should be superimposed over the coronoid process

in a lateral wrist, what should there not be between the trapezium and the base of the 1st metacarpal?

The joint space between the trapezium and the base of the 1st metacapral should be free of superimposition

in a lateral wrist the, what should be aligned with the forearm

The long axis of the first metacarpal should be aligned parallel with the forearm

part position in a lateral wrist

The medial aspect of arm is adjacent to the IR - Wrist true lateral (distal radius and ulna superimposed) - Carpals centered to IR

how are the medial carpals in a pa wrist projection

The medial carpals are superimposed

In a PA oblique wrist projecion the trapezium and trapezoid should be how

The trapezium and trapezoid should be demonstrated without superimposition.

in a Modified Stecher Method, how is the wrist and what is the CR angle?

Wrist horizontal (parallel); CR angled proximally 20

describe superoinferior projection patient position

Wrist is dorsiflexed with palm resting on IR; patient leans forward to place carpal canal in profile;

describe patient position inferosuperior projection

Wrist is hyperextended (dorsiflexed) with long axis of hand as vertical as possible; rotate hand 10° internally; forearm horizontal;

in a modified stecher method how is the wrist positioned

Wrist positioned as for a PA projection

in a PA wrist the radius and ulna are

are separated, the distal radioulnar joint is open

The physician wants to rule out abnormal calcifications in the dorsal carpal

carpal bridge method would best demonstrate this region

A patient with a history of carpal tunnel syndrome comes to radiology. The physician wants to rule out abnormal calcifications in the carpal canal

gaynor-hart method would best demonstrate this region

in a PA wrist projection the navicular is:

is foreshortened

in a PA wrist projection the trapezoid is:

is superimposed on the trapezium

colles fracture of radius

posterior displacement (Colles)

carpal bridge method is also known as the :

tangenital projection