Fingers, Thumb, Hand, and Wrist Procedures (10/16/2023, 10/18/2023, & 10/23/2023) (copy)

How should a patient generally be sitting for a finger/thumb x-ray?

90^o to table with arm flexed 90^o

How are arrow markers used on finger/thumb/hand/wrist x-rays?

point to the specific area of pain/injury

Do you use a grid for finger/thumb/hand/wrist x-rays?

no (done tabletop with no grid)

What is a typical finger routine?

PA, 45^o oblique, lateral

Explain the positioning and centering for a PA finger x-ray

positioning

• arm rotated medially to place into PA projection

• individual finger to midline of IR

• arm down long axis of IR

centering

• 40 in SID

• ray perpendicular

• centered to PIP

  • MCP joint if pain is at the knuckle

• cone to area of interest

What do you need to make sure you have on a PA finger x-ray? (film eval)

• 1 in around digit

• number markers

• joint spaces

• equal concavity

• equal soft tissue

Explain the positioning and centering for a PA oblique finger x-ray

positioning

• rotate hand 45^o laterally

  • or medially if looking at 2^nd digit

• keep finger immobilized and parallel to IR

  • use sponge if needed

centering

• perpendicular

• center to PIP

  • or MCP if pain is at knuckle

• cone to area of interest

What do you need to make sure you have on a PA oblique finger x-ray? (film eval)

• phalanges, joint spaces, distal MCs

• nail bed

• concavity

• soft tissue

• number marker

Explain the positioning and centering for a lateral finger x-ray

positioning

• mediolateral

  • 2^nd digit (possibly 3^rd depending on patient comfort)

• lateromedial

  • 3^rd, 4^th, 5^th digits

• extend only the finger of interest

• keep immobilized

centering

• perpendicular

• centered to PIP

  • MCP if pain is at knuckle

What do you need to make sure you have on a lateral finger x-ray? (film eval)

• phalanges, joint spaces, distal MCs

• nail bed

• concavity

• soft tissue

• number marker

How should finger images be sent?

as if putting your own finger up on the wall

Explain the positioning and centering for an AP thumb x-ray

positioning

• turn hand in extreme internal rotation to achieve AP view

• hold other fingers back

centering

• perpendicular

• centered at 1^st MCP

Why do we use AP instead of PA for thumbs?

PA has a greater OID

What do you need to make sure you have on an AP thumb x-ray? (film eval)

• number marker (#1)

• phalanges, joint spaces

• must include the CMC joint

• nail bed

• concavity

• soft tissue

What carpal is included in the CMC joint and therefore included in thumb x-rays?

trapezium

Explain the positioning and centering for an oblique thumb x-ray

positioning

• hand in PA position

  • this automatically puts thumb at 45^o

centering

• perpendicular

• centered at 1^st MCP

What do you need to make sure you have on an oblique thumb x-ray? (film eval)

• phalanges, joint spaces, distal MC

• CMC joint

• nail bed

• concavity

• soft tissue

• number marker (#1)

Explain the positioning and centering for a lateral thumb x-ray

positioning

• hand in PA

  • rotate to make thumb lateral

centering

• perpendicular

• centered at 1^st MCP joint

What do you need to make sure you have on a lateral thumb x-ray? (film eval)

• phalanges, joint spaces, distal MC

• CMC joint

• nail bed

• concavity

• soft tissue

• number marker (#1)

What is a typical hand routine?

PA, 45^o oblique, lateral

Explain the positioning and centering for a PA hand x-ray

positioning

• 90^o to table with arm flexed 90^o and resting flat

• palmar surface down and fingers spread slightly

• long axis of hand to long axis of IR

centering

• perpendicular

• centered at 3^rd MCP

What do you need to make sure you have on a PA hand x-ray? (film eval)

• MC heads free of superimposition

• joint spaces

• oblique view of thumb

• concavity and soft tissue

• 1-2 in of distal forearm (radius and ulna)

• marker (on either side)

Explain the positioning and centering for a PA oblique hand x-ray

positioning

• arm resting with palmar surface down

• rotate hand laterally so MCP joints for 45^o angle with IR

• digits separated and parallel to IR

centering

• perpendicular

• centered at 3^rd MCP

What do you need to make sure you have on a PA oblique hand x-ray? (film eval)

• heads of all MCs

• space between MC shafts

• concavity

• soft tissue

• marker

Explain the positioning and centering for a lateral hand x-ray

positioning

• arm resting flat with ulnar side down (lateromedial projection)

• fan lateral

  • separate fingers, but keep parallel to IR

  • bring thumb around but DO NOT keep it touching the index finger

• extension

  • extend fingers and keep phalanges superimposed

  • for foreign body visualization, displacement fractures of MCs or pt is unable to fan

centering

• perpendicular

• centered at 2^nd MCP

What do you need to make sure you have on a lateral hand x-ray? (film eval)

• lateral view of each finger (fan)

• carpals, MCs, and radius/ulna are superimposed

• PA view of thumb

• marker

• orientation

What is a typical wrist routine?

PA, 45^o oblique, lateral, ulnar deviation

Explain the positioning and centering for a PA wrist x-ray

positioning

• hand placed palmar surface down

• make a fist (to place wrist closer to IR)

centering

• perpendicular

• centered at midcarpal area

What do you need to make sure you have on a PA wrist x-ray? (film eval)

• marker

• scaphoid fat stripe

• 2 in past each joint

• ¼ of MCs

• 2 in of distal radius and ulna

Explain the positioning and centering for a PA oblique wrist x-ray

positioning

• arm prone with palmar surface down

• rotate wrist laterally 45^o

centering

• perpendicular

• centered at midcarpal area

What do you need to make sure you have on a PA oblique wrist x-ray? (film eval)

• ulnar styloid

• visualization of trapezium and scaphoid

• marker

Explain the positioning and centering for a lateral wrist x-ray

positioning

• arm resting outward on ulnar side (lateromedial projection)

• extend fingers

• hand, wrist, AND forearm in true lateral

centering

• perpendicular

• centered at midcarpal area

What do you need to make sure you have on a lateral wrist x-ray? (film eval)

• radius and ulna superimposed

• pronator fat stripe

• marker

Explain the positioning and centering for a PA axial (scaphoid) wrist x-ray

positioning

• ulnar deviation

  • evert hand as much as possible toward ulnar side

• palmar surface down

• demonstrates carpals on lateral side of wrist

What do you need to make sure you have on a PA axial wrist x-ray? (film eval)

scaphoid without superimposition and foreshortening

What are the base techniques for finger/thumb x-rays?

55 kVp @ 0.8 mAs

What are the base techniques for hand x-rays?

60 kVp @ 1 mAs

(1.2 mAs for lateral)

What are the base techniques for wrist x-rays?

60 kVp @ 1.2 mAs

What should the exposure index be for finger/thumb/hand/wrist x-rays?

EI#: 200-600

S#: 150-400

Explain the benefit of the AP wrist special view

opens up intercarpal joint spaces better than PA

Explain the positioning and centering for the wrist AP oblique special view

positioning

• arm resting outward with palmar surface up

• rotate wrist medially 45^o

• pisiform must be free of superimposition

centering

• perpendicular

• centered at midcarpal area

Explain the lateral wrist projection for trauma

• shoot through

  • horizontal CR

  • either lateromedial or mediolateral

• build arm up on a sponge

What is the typical trauma routine?

PA, PA oblique, shoot through lateral

Explain the radial deviation image

Shows interspaces on the medial side of the wrist (lunate, triquetrum, pisiform, and hamate)

When is Stecher method used?

when patient cannot do ulnar deviation

Explain the 3 positioning methods and centering for the Stecher method wrist x-ray

positioning

• arm resting outward with palmar surface down

• elevate cassette on 20 degree angled sponge with CR perpendicular

• elevate hand on 20 degree angled sponge with CR perpendicular

• hand in PA and CR is angled 20 degrees cephalically

Explain positioning and centering for the Gaynor-Hart method

positioning

• forearm parallel to IR/tube

• hyperextend the wrist with fingers out of the way

• rotate hand 10^o internally to make wrist flat against IR

centering

• central ray 25-30^o toward long axis of hand

• centered ~1 in distal to base of 3^rd MC

What do you need to make sure you have on a Gaynor-Hart wrist x-ray? (film eval)

• bones

  • 1^st MC

  • trapezium

  • scaphoid

  • hamate

  • pisiform (w/o superimposition of hamulus)

• carpal canal

What is the purpose of the Gaynor Hart method?

r/o abnormal calcifications or bony changes that may impinge on median nerve (and cause carpal tunnel syndrome)