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.
carpal tunnel syndrome
is a common painful disorder of the wrist and hand that results from compression of the median nerve as it passes through the center of the wrist.
fracture
is a break in the structure of bone caused by a force (direct or indirect).
trauma fractures
Barton fracture: Fracture and dislocation of the posterior lip of the distal radius involving the wrist joint.
* Bennett fracture: Fracture of the base of the first metacarpal bone, extending into the carpometacarpal joint, complicated by subluxation with some posterior displacement.
* Boxer fracture: Transverse fracture that extends through the metacarpal neck; most commonly seen in the fifth metacarpal.
* Colles fracture: Transverse fracture of the distal radius in which the distal fragment is displaced posteriorly; an associated ulnar styloid fracture is seen in 50% to 60% of cases.
* Smith fracture: Reverse of Colles fracture, or transverse fracture of the distal radius with the distal fragment displaced anteriorly.
joint effusion
refers to accumulated fluid (synovial or hemorrhagic) in the joint cavity.
osteoarthritis
also known as degenerative joint disease (DJD), is a noninflammatory joint disease characterized by gradual deterioration of the articular cartilage with hypertrophic (enlarged or overgrown) bone formation.
osteomyelitis
is a local or generalized infection of bone or bone marrow that may be caused by bacteria introduced by trauma or surgery
osteopetrosis
is a hereditary disease marked by abnormally dense bone.
osteoporosis
refers to reduction in the quantity of bone or atrophy of skeletal tissue
rheumatoid arthritis
is a chronic systemic disease with inflammatory changes throughout the connective tissues;
ambulatory patient
lateral wrist
trauma patient
ap forearm
routine fingers
- PA
- PA oblique
- Lateral
finger positioning
- Pronate hand with fingers extended
- Center and align long axis of affected finger with long axis of IR
- Separate adjoining fingers from affected finger .
PA oblique positioning
- With fingers extended against 45° foam wedge block, place hand in a 45° lateral oblique (thumb side up)
- Position hand on image receptor so that the long axis of the finger is aligned with the long axis of the IR.
AP projection-thumb
- Internally rotate hand with fingers extended until posterior surface of thumb is in contact with IR. Immobilize other fingers with tape to isolate thumb if necessary (see Fig. 4.51).
- Align thumb with long axis of the IR.
- Center first MCP joint to CR and to center of IR.
Exception—PA (Only if Patient Cannot Position for Previous AP)
Place hand in near-lateral position and rest thumb on sponge support block that is high enough so the thumb is not rotated but is in position for a true PA projection
Pa Oblique Projection—Medial Rotation: Thumb
- Abduct thumb slightly with palmar surface of hand in contact with IR (this action naturally places thumb in a 45° oblique position).
- Align long axis of thumb with long axis of IR.
- Center first MCP joint to CR and to center of IR
PA oblique thumb
CR to first MCP joint.
Ap Axial Projection (Modified Robert Method) 5 —Thumb
Base of first metacarpal is demonstrated for ruling out Bennett fracture.
AP axial projection—Lewis modification
CR 10° to15° to MCP joint
PA projection hand
Pronate hand with palmar surface in contact with IR; spread fingers slightly
* Align long axis of hand and forearm with long axis of IR.
* Center hand and wrist to IR
“FAN” Lateral—Lateromedial Projection: Hand
- Minimum SID—40 inches (100 cm)
- IR size—10 × 12 inches (24 × 30 cm), portrait; smallest IR available and collimate to area of interest
- Nongrid
- kVp range—55 to 65
- Accessories—45° foam step support
Lateral in Extension and Flexion—Lateromedial Projections: Hand
Rotate hand and wrist, with thumb side up, into true lateral position, with second to fifth MCP joints centered to IR and CR.
PA/AP projection wrist
- Align and center long axis of hand and wrist to IR, with carpal area centered to CR.
- With hand pronated, arch hand slightly to place wrist and carpal area in close contact with IR
lateromedial projection wrist
Fractures or dislocations of the distal radius or ulna, specifically anteroposterior fragment displacements for Barton, Colles, or Smith fractures
* Osteoarthritis also may be demonstrated primarily in the trapezium and first CMC joint
Routine
lateromedial projection wrist
Minimum SID—40 inches (100 cm)
* IR size—8 × 10 inches (18 × 24 cm), portrait; smallest IR available and collimate to area of interest
* Nongrid
* kVp range—60 to 70
PA and PA Axial Scaphoid—With Ulnar Deviation: Wrist
if patient has possible wrist trauma, do not attempt this position before a routine wrist series has been completed and evaluated to rule out possible fracture of distal forearm or wrist or both.
PA and PA Axial Scaphoid—With Ulnar Deviation: Wrist
Possible fractures of the scaphoid
PA and PA Axial Scaphoid—With Ulnar Deviation: Wrist
- Angle CR 10° to 15° proximally, along long axis of forearm and toward elbow (CR angle should be perpendicular to long axis of scaphoid).
- Center CR to scaphoid (Locate scaphoid at a point ¾ inch (2 cm) distal and medial to radial styloid process).
PA axial wrist (scaphoid)
ulnar deviation with 15° CR angle.
