exam review
Why do we bend the fingers slightly for a PA projection of the wrist?
To place the wrist/carpal bones in close contact with the image receptor.
Define pivot joints.
uniaxial movement, the joints allow only rotation around a single axis.
a rounded pointed surface of one bone articulates within a ring formed partially by another bone.
The distal radioulnar joint is a pivot joint
What is the central ray location for a PA projection of the wrist?
perpendicular to the midcarpal area.
What is another word for displacement of a bone?
Dislocation of a bone.
Are the carpal bones long bones or short bones?
Short bones
How is the AP forearm projection positioned?
hand supinated
extend elbow
dorsal forearm against the IR
have patient lean laterally
what is the central ray location for a PA projection of the digits 2-5?
The PIP joint (proximal interphalangeal joint)
What is the central ray location for a lateral projection of the wrist?
Perpendicular to the wrist joint.
Why would we do an extension lateral projection versus a fan lateral projection of the hand? what is best demonstrated in each view?
Extension Lateral: localizes foreign bodies and metacarpal fracture displacement.
Fan Lateral: superimposes the metacarpals but shows almost all of the individual phalanges, the most proximal portions of the phalanges remain superimposed.
are the radius and ulna long bones or short bones?
Long bones
What is the purpose of the tubercle?
serves as an attachment site for tendons and ligaments, facilitating muscle attachment and leverage for movement.
What is the central ray location for a PA/AP projection of the first digit (thumb)?
Perpendicular to the MCP joint (metacarpophalangeal joint).
List the carpal bones.
1.trapezium
2. trapezoid
3.scaphoid
4.lunate
5. triquetrum
6.pisiform
7. hamate
8. capitate
How many degrees do we oblique for an oblique hand projection?
45 degrees.
Are the metacarpals long bones or short bones?
Long bones
Define hinge joint.
1.uniaxial movement.
2.A hinge joint permits only flexion and extension. the motion is similar to that of a door.
3.interphalangeal joint and elbow is an example of a hinge joint
What is the central ray location for a PA projection of the hand?
Perpendicular to the 3rd MCP joint
(metacarpophalangeal joint)
What is the largest carpal bone?
The capitate bone
How many degrees do we oblique for an oblique wrist projection?
45 degrees.
This is a type of bone fracture where the bone breaks into multiple fragments or pieces.
Define saddle joint.
What is the central ray location for a Lateral projection of the hand?
perpendicular to the 2nd MCP joint mediolateral
Perpendicular to the 5th MCP for lateromedial.
What is the smallest carpal bone?
The pisiform bone
Are the phalanges long bones or short bones?
Long bones.
What is an avulsion fracture?
when a fragment of bone if pulled away from the main bone mass by a tendon or ligament.