chapter 4 upper limbs Flashcards
how many bones in each hand
there are 27 bones in each hand and wrist
The third group of bones of the hand and wrist are the
carpals
ulnar notch
is a small depression on the medial aspect of the distal radius.
head of the ulna
is located near the wrist at the distal end of the ulna
Interphalangeal Joints
Beginning distally with the phalanges, all IP joints are ginglymus, or hinge-type, joints with movement in two directions only—flexion and extension .
Metacarpophalangeal Joints
The second to fifth MCP joints are ellipsoidal (condyloid)-type joints that allow movement in four directions—flexion, extension, abduction, and adduction.
Carpometacarpal Joints
The first CMC joint of the thumb is a saddle (sellar)-type joint.
Intercarpal Joints
The intercarpal joints between the various carpals have only a plane (gliding) movement.
The wrist joint is
an ellipsoidal (condyloid)-type joint and is the most freely movable, or diarthrodial, of the synovial classification.
five ligaments of the wrist
Dorsal radiocarpal ligament
Palmar radiocarpal ligament
Triangular fibrocartilage complex (TFCC)
Scapholunate ligament
Lunotriquetral ligament
ulnar deviation
ulnar deviation movement of the wrist “opens up” and best demonstrates the carpals on the opposite side (the radial or lateral side) of the wrist—the scaphoid, trapezium, and trapezoid.
radial deviation
A less frequent PA wrist projection involves the radial deviation movement that opens and best demonstrates the carpals on the opposite, or ulnar, side of the wrist—the hamate, pisiform, triquetrum, and lunate.
3 significant fats pads of the elbow
anterior
posterior
supinated
SID for upper limbs
40
principal exposure factors
- Lower to medium kVp (60 to 80—digital)
- Short exposure time
- Small focal spot
- Adequate mAs for sufficient density (brightness)
image receptors
Grids are not generally used for the upper limb examinations unless the body part (e.g., the shoulder) measures greater than 10 cm.
3 centering positions
- Part should be parallel to plane of IR.
- CR should be 90° or perpendicular to part and IR, unless a specific CR angle is indicated.
- CR should be directed to correct centering point.
digital imaging considerations
collimation
accurate centering
Grid use with digital systems
evaluation of exposure indicator
Bone metastases
refers to transfer of disease or cancerous lesions from one organ or part that may not be directly connected.
bursitis
is inflammation of the bursae or fluid-filled sacs that enclose the joints; the process generally involves the formation of calcification in associated tendons, 4 which causes pain and limited joint movement.