Thumb & Finger - Unit 4

Name of the joint between the two phalanges of the thumb

Interphalangeal Joint or IP

Name the phalanges of the fingers

proximal, middle, and distal

Name the joint between the distal and middle phalanges of the fingers

Distal Interphalangeal Joint or DIP

Name the joint between the middle and proximal phalanges of the finger

Proximal Interphalangeal Joint or PIP

Fracture and dislocation of the posterior lip of the distal radius involving the wrist joint

Barton's Fracture

Transverse fracture that extends through the metacarpal neck, most commonly seen in the 5th metacarpal

Boxer's Fracture

Fracture of the distal phalanx caused by a ball striking the end of extended finger

Baseball(Mallet) Fracture

Fracture that does not traverse through the entire bone

Incomplete Fracture

Fracture of wrist from fall forward on outstretched arm. Fragment displaced posteriorly

Colles' Fracture

Partial dislocation of radial head of a child's arm, caused by a hard pull of hand or wrist

Nursemaid's (Jerked) Elbow

Also known as Reverse Colles, fracture of the distal radius with fragment displaced anteriorly.

Smith's Fracture

Fracture through the epiphyseal plate- one of the most easily fractured sites in the long bones of children

Epiphyseal Fracture

Increase mAs 50-60% or +5-7 kV

Small to Medium dry plaster cast

Increase mAs 100% or +8-10 kV

Large or Wet plaster cast

Increase mAs 25%-30% or +3-4 kV

Fiberglass cast

SID for finger or thumb

40 inches

Also called luxation

Dislocation

Partial dislocation

Subluxation

A forced wrenching or twisting of a joint that results in a partial rupture or tearing of support ligaments without dislocation

Sprain

A bruise type of injury with a possible avulsion fracture

Contusion

Fracture that does not break through the skin

Simple (Closed)Fracture

Fracture with part of bone protruding through the skin

Compound (Open) Fracture

Fracture where the bone is splintered or crushed at the site of impact, two or more fragments

Comminuted Fracture

Fracture with one fragment is firmly driven into the other

Impacted Fracture

CR position for finger

PIP Joint

Occurs when a bone is displaced from the joint, articular contact of the bones that make up a joint is completely lost

Dislocation

If patient can assume position, use mediolateral rotation for the 2nd digit to reduce what?

OID

kV range for fingers and thumb

50-60 kV

CR position for the thumb

First MCP joint

PA Stress "Skier's Thumb" Projection is also known as

Folio Method

Projection to show sprain or tearing of ulnar collateral ligament of the thumb at the MCP joint, result of acute hyperextension of thumb

Folio Method

Degree of obliquity for a PA Oblique Thumb

45 degrees

This projection demonstrates fractures or dislocations of the first CMC joint

Modified Robert's Method

Used to rule out Bennett's Fracture

Modified Robert's Method

Type of shielding for finger or thumb

Gonadial

Angle of the CR for the Modified Robert's Method

15 degrees

CR directed ____________ for the Modified Robert's Method

Proximally (toward wrist)

CR enters the ____________ joint for Modified Robert's Method

First CMC Joint

How much of the metacarpal must be included for a thumb?

Entire first metacarpal

Abduct thumb with palmer surface of hand in contact with cassette

Position for PA Oblique Projection

PA Thumb causes an increase in _____

OID

CR is directed __________ to IR for an AP Thumb

Perpendicular

If patient cannot do an AP Thumb projection, this projection can be used

PA Thumb

Rotate hand __________ for AP Thumb

Internally

Mediolateral should be used for the ___________ to reduce OID

2nd digit

Long axis of finger should be __________ to the IR

Parallel

Rotation for 2nd digit PA Oblique Projection

Medial

Rotation for 3rd-5th digits PA Oblique Projecton

Lateral

mAs for fingers

2 mAs

mAs for thumb

3 mAs

Type of screen used for finger or thumb

Detail Screen

1st -5th IP joints are what type of joints

Ginglymus or Hinge type

Movement directions of Ginglymus joint

Flexion and Extension

Classification of finger and thumb joints

Synovial

Diarthrodial are ______________ movable

Freely

The 3 joints of the 2nd-5th digits

DIP,PIP,MCP

First Digit

Thumb

Fifth Digit

Little finger

3 parts of a phalanx

Head, body (shaft), base

To keep joint space open, keep finger _______ to cassette

Parallel

Exposure factors for thumb or finger

low to medium kV (50-70), short exposure time, small focal spot, adequate mAs for sufficient density

Use grid when body part larger than _______cm

10 cm

Can be used to prevent exposure form scatter and secondary radiation when more than one image taken on an imaging plate

Lead masking

How much of the imaging plate must be exposed for accurate exposure index in CR system

30%

CR should be ____________ to body part and IR if there is no angle

90 degrees or perpendicular

Close _________ helps to reduce patient radiation dose

Collimation

As Low As Reasonably Achievable

ALARA principle

Lowest exposure factors to produce an optimal image

highest kV possible and lowest mAs

This produces a noisy (grainy) image

Insufficient mAs

Break in the bone caused by force

Fracture

Widening of inner MCP joint space of thumb and increase in degrees of angle of MCP line

Skier's thumb

50-60% of these cases also involve an ulnar styloid fracture

Colles' Fracture

Chronic systemic disease, inflammatory changes throughout the body's connective tissues, soft tissue swelling most prevalent around the ulnar styloid.

Rheumatoid Arthritis (RA)

3 times more common in women than men

RA

Early bone erosions at the 2nd and 3rd MCP joints or the 3rd PIP joint

RA

Closed joint spaces with subluxation of MCP joints

RA

Fluid-filled joint space with possible calcifications

Bursitis

Fluid-filled joint cavity

Joint Effusion

Narrowing of joint space with periosteal growth on the joint margins

Osteoarthritis (DJD)

Soft tissue swelling and loss of fat pad detail visibility

Osteomyelitis

Chalky white or opaque appearance with lack of distinction between the bony cortex and the trabeculae

Osteopetrosis

Marble bone

Osteopetrosis

Decrease in bone density, thin cortex

Osteoporosis

_____ exposure factors for Osteoporosis.

Decrease

_______ exposure factors for RA

Decrease

_______ exposure factors for Osteopetrosis

Increase

Mixed areas of sclerotic and cortical thickening with radiolucent lesions

Paget's Disease

Cotton wool appearance

Paget's Disease

Most common type of benign bone tumor, usually in 10-20 year old

Osteochondroma

Another name for Osteochondroma

Exostosis

Arises from the outer cortex with the tumor growing parallel to the bone, most common in the knee but also in the pelvis and scapula of children and young adults

Osteochondroma

Slow-growing benign cartilaginous tumor

Enchondroma

Most often found in small bones of the hands and feet of adolescents and young adults

Enchondroma

well-defined, radiolucent- appearing tumors with thin cortex, pathologic fracture with minimal trauma

Enchondroma

Benign bone or cartilaginous tumor

Chondroma

Slow-growing malignant tumor of the cartilage

Chondrosarcoma

Dense calcifications within the cartilaginous mass

Chondrosarcoma

Common primary malignant bone tumor in children and young adults

Ewing's Sarcoma

Arises from the bone marrow, symptoms of low-grade fever and pain, prognosis poor by time evident on radiographs

Ewing's Sarcoma

Stratified new bone formation,"onion peel" appearance

Ewing's Sarcoma