Hand Anatomy/ Finger projections

interphalangeal (IP) joints

articulations between phalanges (1) only in thumb

metacarpophalengeal (MCP) joints

articulations between the heads of the metacarpals and the proximal phalanges (5)

ambulatory patients are positioned where?

at end of x-ray table - affected extremity rests on IR placed on tabletop.

why should you shield on hand projections?

because the x-ray tube is shooting right by their lap, scatter radiation will go into their lap.

distaI interphalangeal (DIP) joints

between the distal phalanx and middle phalanx (4)

carpals

bone of the wrist

phalanges

bones of the digits (fingers, and thumb)

metacarpals

bones of the palm

how are phalanges named?

by location

how are nonambulatory patients are positioned?

can set a board across stretcher

what does each phalanx have?

head, body and base

what are the 3 phalanges of digits 2 through 5 called?

middle, proximal, and distal

what are breathing techniques for upper extremity?

no breathing instructions, just have patient stay still to reduce motion.

the distal phalanges are farthest from the what?

palm

the proximal phalanx are closest to what?

palm

part position for PA oblique Digits 2 to 5

palmar surface resting on 45 degree wedge sponge or hand rotated with digits extended parallel with the IR plane so that the IP joint spaces are open. - digit of interest seperated with no soft tissue overlap

central ray for PA for digits 2 to 5

perpendicular to IR enters patient at PIP joint

CR for PA oblique thumb

perpendicular to MCP joint

central ray for AP thumb

perpendicular to MCP joint

CR for lateral thumb

perpendicular to MCP joint of thumb

central ray for PA oblique digits 2 to 5

perpendicular to PIP joint of affected digit

what are the 2 phalanges of the first digit called?

proximal and distal

What are some patient preparation for hand x-ray?

watches, rings, bracelets

cassette size for digits

10 x 12 or smaller if available

how many phalanges are in the thumb?

2

how many bones are in the hand?

27

how many phalanges are in digits 2 to 5?

3

SID for hand

40 inches

where does the CR enter the 3rd digit for the PA projection? A. 3rd DIP joint B. 3rd PIP joint C. 3rd MCP joint D. base of the 3rd metacarpal

B. 3rd PIP joint

where does the collimation extend to proximally for the AP projection of the first digit? A. head of the first metacarpal B. base of the proximal phalange C. 1 inch (2.5 cm) proximal to the first CMC joint D. 1 inch (2.5 cm) proximal to radiocarpal joints

C. 1 inch proximal to the first CMC joint

the articulation between the middle and distal phalanges on the 2nd digit is named: A. second MCP joint B. 2nd IP joint C. DIP joint of the 2nd digit D. PIP joint of the 2nd digit

C. DIP joint of the second digit, located between the middle and distal phalanges on digits 2 to 5

central ray for lateral digits for 2 to 5

- directed perpendicular to the IR - enters patient at PIP joint of affected digit.

Lateral digit 2 and 3rd part position

- extend affected digit with lateral surface in contact with IR (mediolateral projection) - close the rest of the digits in a fist

Lateral digit 4th & 5th digits part position

- extend affected digit with medial surface in contact with IR (lateromedial projection) - close the rest of the digits into a fist.

PA digits 2 to 5 part position

- extended with palmar surface in center of IR - long axis of digit aligned parallel to IR - separate digits slightly with affected digit in center of IR.

AP thumb part position

- hand in extreme medial rotation - posterior surface of thumb on IR - MCP joint centered to IR - long axis of thumb aligned parallel - hold other extended digits back with tape or the opposite hand - check thumb position to ensure true AP projection

PA oblique thumb part position

- palmar surface on IR - ulnar-deviate hand slightly - align long axis of thumb parallel - center MCP joint to IR

what are the divisions of the hand bones?

- phalanges (14 bones) - metacarpals (5 bones) - carpals (8 in each)

part position for lateral thumb

-palmar surface on IR - align long axis of thumb parallel - center MCP joint to IR - rotate thumb until lateral surface is on IR (mediolateral projection)

what is collimation for digits?

1 inch on all sides including 1 inch proximal to MCP joint.