Ch 4 Upper Limb; Flash Cards
What are the four main groups of the upper limb?
1- hand & wrist
2- forearm
3-arm (humerus)
4- shoulder girdle
How many bones are in each hand & wrist?
27 bones
What are the three groups the hand & wrist are divided into? & how many bones in each group?
1- phalanges (fingers & thumb) ; 14 bones
2- metacarpals (palm) ; 5 bones
3- carpals (wrist) ; 8 bones
What are the joints of the hand?
1- Interphalangeal (IP) Joint
2- Metacarpophalangeal (MCP) Joint
3-Carpometacarpal (CMC( Joint
4- Distal Interphalangeal (DIP) Joint
5- Proximal Interphalangeal (PIP) Joint
Where is the interphalangeal (IP) Joint located?
The thumb between the two phalanges
Where is the first Metacarpophalageal (MCP) Joint located?
This joint is located between the first metacarpal and the proximal phalanx of the thumb
Where is the Distal Interphalangeal (DIP) Joint located?
starting from the most distal portion of each digit.
Where is the Proximal Interphalageal (PIP) Joint located?
these are after the DIP joint
Where is the Carpometacatpal (CMC) Joint located?
these are at the proximal end. the metacarpals articulate with the respective carpals.
What are the five metacarpals that articulate with specific carpals?
- first metacarpal with trapezium
- second metacarpal with trapezoid
- third metacarpal with capitate
4/5. fourth and fifth metacarpal with hamate
What are the two rows of carpals?
- Proximal Row
- Distal Row
What bones consists of the Proximal Row of the wrist?
1- Scaphoid ; first & is on thumb side
2- Lunate; second carpal. it is moon shaped
3. Triquetrum; third. distinguished by its pyramidal shape
4. Pisiform; fourth & is pea shaped. it is the smallest
What bones consists of the Distal Row of the wrist?
- Trapezium; first & on the thumb side
- Trapezoid; second and is the smallest in the distal row
- Capitate; third & it a large bone
- Hamate; the last carpals in the distal row . it is easily distinguished by the hooklike process.
What two bones are in the forearm?
- Radius
- Ulna
Describe what sides the Radius & Ulna are on.
- Radius is lateral, or thumb side
- Ulna is on the medial side
What joints do the radius & the unla use to articulate with each other?
- the proximal radioulnar joint
- the distal radioulnar joint
What do the proximal & distal radioulnar joints allow for the radius & ulna to do?
these joints allow for the rotational movement of the wrist and hand.
What is a True Lateral Elbow?
A true lateral elbow is an accurate lateral with 90 degree flexion along with possible associated visualization of fat pads.
What are the three concentric arcs you should see in a true lateral elbow radiograph?
- Trochlear Sulcus (the smallest)
- an intermediate arc that appears double lined as the outer ridges or rounded edges of the capitulum and trochlea
- the trochlear notch of the ulna is the third arc.
Why is it important to evaluate the far pads in a radiograph?
Because in some cases displacement of an adjoining fat pad or band may be the only indication of disease or significant injury or fracture within a joint region
Name the two important fat stripes in the wrist
- Scaphoid fat stripe
- Pronator fat stripe
Name the three significant fat pads/stripes of the elbow
- Anterior fat pad
- Posterior fat pad
- Supinator fat stripe
How are ambulatory patients generally positioned for a radiograph of the upper limb?
the patient is seated sideways at the end of the table, in a position that is neither strained nor uncomfortable
What is the common minimum SID (source to image distance) for upper limb radiographs?
the common minimum SID is 40 to 44 inches
What are the principal exposure factors for Radiography of the upper limbs?
- lower to medium kVp (60 to 80)
- short exposure time
- small focal spot
- adequate mAs for sufficent density (brightness)
Are grids generally used for upper limb examinations?
No, they are not unless the body part measures greater than 10 cm
What is the most common radiographic examination for bursitis & what does it show?
AP and lateral joint. It will show fluid-filled joint space with possible calcification
What are the most common radiographic examination for carpal tunnel syndrome & what does it show?
PA and lateral wrist. this will show possible calcification in carpal sulcus, enlargement of wrist ligaments and median nerve compression
What is the most common radiographic examination for fractures & what does it show?
AP and lateral of long bones; AP, lateral and oblique if the joint is involved. It will so disruption in bony cortex with soft tissue swelling
Explain the part position for a PA Projection on Fingers
- pronate hand with fingers extended
-center and align long axis of affected finger with long axis of IR
-separate adjoining fingers from affected finger
What is the central ray position for the PA Projection for Fingers
the CR is perpendicular to the IR, directed to the PIP joint
what anatomy is demonstrated in a PA Projection (Fingers)
the anatomy demonstrated is the Distal, middle, and proximal phalanges, distal metacarpals, and the associated joints.
What is the part position for PA Oblique Projection- Medial or Lateral Rotation for fingers?
-with fingers extended against 45 degree foam wedge block, place hand in a 45 degree lateral oblique (thumb side up)
-position hand on IR so that the long axis of the finger is aligned with the long axis of the IR
-separate fingers and carefully place finger that is being examined against block, so it is supported in a 45 degree oblique and parallel to IR
what is the central ray for a PA Oblique projection; medial or lateral rotation-fingers?
the central ray is perpendicular to IR, & directed to the PIP joint
what is the anatomy demonstrated for a PA Oblique projection; medial or lateral rotation-fingers?
the anatomy demonstrated is the oblique view of distal, middle, and proximal phalanges along with the distal metacarpals and associated joints
what are the clinical indications for a lateromedial/mediolateral projections of the finger?
-fractures and dislocations of the distal, middle, and proximal phalanges, distal metacarpals and associated joints
-pathologic processes, such as osteoporosis and osteoarthritis
how is the patient positioned for a lateromedial/mediolateral projections of the finger?
the patient is seated at the end of the table, with elbow flexed about 90 degrees with hand and wrist resting on IR and fingers extended
what anatomy is demonstrated on a lateromedial/mediolateral projections of the finger?
the anatomy demonstrated is the lateral views of distal, middle, and proximal phalanges, along with distal metacarpals and associated joints are visible
what is the IR Size for an AP Projection of the Thumb
the IR Size is 8 x 10 inches (18 x 24 cm), portrait
what is the central ray for an AP Projection of the thumb?
the central ray is perpendicular to the IR, to first MCP joint
what is the part position for a PA 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
what is the part position for a PA oblique projection of the hand?
-pronate hand on IR; center and align long axis of hand with long axis of IR
-rotate entire hand and wrist laterally 45 degrees and support with radiolucent wedge or step block so that all digits are separated and parallel to IR
what is the central ray for a “FAN” lateral/lateromedial projection of the hand?
the central ray is perpendicular to IR, directed to second MCP joint
What projections are alternatives for the Fan Lateral projection?
the alternatives are lateral in extension and flexion
what is the part position for a PA (AP) Projections of the 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
How should you collimate for a PA (AP) Projection of the wrist?
you should collimate to wrist on all four sides; include distal radius and ulna and midmetacarpal are
What are the clinical Indications for a Lateromedial Projection of the wrist?
the clinical indications are
-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
what is the central ray for a PA and PA Axial Scaphoid with Ulnar Deviation of the Wrist?
the central ray is
-angle CR 10 degree to 15 degrees proximally, along long axis of forearm and toward elbow
-center CR to scaphoid
What are the clinical indications for Carpal Canal (Tunnel)- Tangential, Inferosuperior Projection of the wrist?
the clinical indications are
-rule out abnormal calcification and bony changes in the carpal sulcus that may impinge on the median nerve, as with carpal tunnel syndrome
-possible fractures of the hamulus process of the hamate, pisiform, and trapezium
how should you collimate for an AP Projection of the Forearm?
collimate lateral borders to actual forearm area with minimal collimation at both ends to avoid excluding anatomy at either joint. considering divergence of the x-ray beam, ensure that a minimum of 1 to 1.5 inches distal to wrist and elbow joints is included on IR
