Ch. 04 Upper Limb (Hand, wrist, Forearm)
PA hand anatomy exercise
(A. First carpometacarpal joint of right hand B. First metacarpal of right hand C. First metacarpophalangeal joint of right hand D. Proximal phalanx of first digit (or thumb) of right hand E. Interphalangeal joint of first digit (or thumb) of right hand F. Distal phalanx of first digit (or thumb) of right hand G. Second metacarpophalangeal joint of right hand H. Proximal phalanx of second digit of right hand I. Proximal interphalangeal joint of second digit of right hand J. Middle phalanx of second digit of right hand K. Distal interphalangeal joint of second digit of right hand L. Distal phalanx of second digit of right hand M. Middle phalanx of fourth digit of right hand N. Distal interphalangeal joint of fifth digit of right hand O. Proximal phalanx of third digit of right hand P. Fifth metacarpophalangeal joint of right hand Q. Fourth metacarpal of right hand R. Fifth carpometacarpal joint of right hand)
Exposure Factors
1. Lower to medium kV (55 to 70—analog; 60 to 80—digital) 2. Short exposure time 3. Small focal spot 4. Adequate mAs for sufficient density (brightness)
Correct Centering
1. Part should be parallel to plane of IR. 2. CR should be 90° or perpendicular to part and IR, unless a specific CR angle is indicated. 3. CR should be directed to correct centering point.
How many bones on each hand and wrist?
27; 1. Phalanges (fingers and thumb): 14 2. Metacarpals (palm): 5 3. Carpals (wrist): 8
Lead Shielding
A lead, vinyl-covered shield should be draped over the patient's lap or gonadal area
Forearm Routine
AP and lateral; F: Fractures and dislocations of the radius or ulna, osteomyelitis or arthritis Pt: with hand and arm fully extended and palm up (supinated) Po: Drop shoulder to place entire upper limb on same horizontal plane / both wrist and elbow joints are included CR: mid-forearm Col: Considering divergence of the x-ray beam, ensure that a minimum of 3 to 4 cm (1 to 1.5 inches) distal to wrist and elbow joints is included on IR
Po: hyperextend wrist (dorsiflex) until the long axis of the metacarpals and the fingers are as near vertical (90° to forearm) / Rotate entire hand and wrist about 10° internally (toward radial side) to prevent superimposition of pisiform and hamate (separated)
CR: Angle CR 25° to 30° to the long axis of the hand / Direct CR 2 to 3 cm (1 inch) distal to the base of third metacarpal or midpoint of the carpal canal Sonography for carpal tunnel: noninvasive imaging of the carpal tunnel and related anatomy
Thumb routine: AP, PA oblique, Lateral
Collimation: all of first metacarpal and trapezium is included; CR: First MCP joint
Finger Routine: PA, PA oblique, Lateral
Collimation: four sides to area of affected finger and distal aspect of metacarpal
annular ligament
Connects the head of the radius to the ulna
Image Receptors
Conventional analog (film-screen) imaging: IR with detail-intensifying screen; Grids are not used unless the body part (e.g., the shoulder) measures larger than 10 cm.
PA thumb projection (not advisable because of increased OID)
Exception; 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 that thumb is not rotated but is in position for a true PA projection;
AP Axial Projection / Modified Robert's Method/ Lewis modification
F: Bennett's fracture; fractures, dislocations, or pathology of the base of the first metacarpal and trapezium; Pt: Seat patient parallel to end of table, with hand and arm fully extended; No rotation Po: Rotate arm internally until posterior aspect of thumb rests on IR CR: the first MCP joint with a 10° to 15° proximal angle
Lateromedial Projection: Elbow
F: Elevated or displaced fat pads of the elbow joint may be visualized Pt: Drop shoulder so that humerus and forearm are on same horizontal plane / Rotate hand and wrist into true lateral position, thumb side up. Place interepicondylar plane perpendicular to the IR Po: one-half of radial head superimposed by the coronoid process/ olecranon process visualized / three concentric arcs of the trochlear sulcus, double ridges of the capitulum and trochlea, and the trochlear notch of the ulna / superimposition of the humeral epicondyles
PA Projection: Fingers
F: Fractures and dislocations of the distal, middle, and proximal phalanges; distal metacarpal; osteoporosis and osteoarthritis Fingers Patient: Seat patient at end of table, with elbow flexed about 90° with hand and wrist resting on IR and fingers extended Position: Pronate hand with fingers extended; Center and align long axis of affected finger with long axis of IR CR: PIP joint (include metacarpal)
PA Projection—Radial Deviation: Wrist
F: Fractures of the carpal bones on the ulnar side of the wrist, especially the lunate, triquetrum, pisiform, and hamate Po: invert the hand (move medially toward thumb side) CR: midcarpal area Col: Distal radius and ulna, carpals, and proximal metacarpals are visible.
Acute Flexion Projections: Elbow (AP Projections of Elbow in Acute Flexion)
F: Soft tissue detail is not readily visible / when the elbow cannot be extended to any degree Po: two projections are required—one with CR perpendicular to the humerus and one with CR angled so that it is perpendicular to the forearm Distal humerus CR: perpendicular to IR and humerus, directed to a point midway between epicondyles Proximal forearm CR: perpendicular to forearm (angling CR as needed), directed to a point approximately 2 inches (5 cm) proximal or superior to olecranon process
PA Stress Thumb Projection / Folio Method
F: Sprain or tearing of ulnar collateral ligament of thumb at MCP joint; acute hyperextension of thumb; skier's thumb injury Pt: Seat patient at end of table with both hands extended and pronated on IR Po: both hands side by side to center of IR, rotated laterally into ±45° oblique position, resulting in PA projection of both thumbs; thumbs parallel to IR; before exposure, ask patient to pull thumbs apart firmly and hold CR: midway between two MCP joints Co: from CMC joints to distal phalanges
Carpal Canal (Tunnel)—Tangential, Inferosuperior Projection: Wrist / Gaynor-Hart Method
F: abnormal calcification and bony changes in the carpal sulcus affected by median nerve, as with carpal tunnel syndrome; Possible fractures of the hamulus process of the hamate, pisiform, and trapezium
Lateral in Extension and Flexion—Lateromedial Projections: Hand
F: alternative to the fan lateral for localization of foreign bodies; demonstrates anterior or posterior displaced fractures of the metacarpals CR: second to fifth MCP joints
Lateromedial Projection: Wrist
F: anteroposterior fragment displacements for Barton's, Colles, or Smith's fractures/ Osteoarthritis in the trapezium and first CMC joint Pt: Place wrist and hand on IR in thumb-up lateral position. Shoulder, elbow Po: hand and wrist into a true lateral position; ulnar head and distal radius superimposed; proximal second through fifth metacarpals superimposed
AP Oblique Bilateral Projection: Hand / Norgaard Method / "ball-catcher's position (modified position with fingers partially flexed)
F: early evidence of rheumatoid arthritis at the second through fifth proximal interphalangeal (PIP) and MCP joints; May demonstrate fractures of the base of the fifth metacarpal Po: Supinate hands; internally rotate hands 45° and support posterior aspect of hands on 45° radiolucent blocks CR: midway between both hands at level of fifth MCP joints
Radial Head—Lateromedial Projections: Elbow (4 projections with different rotation of the hand and wrist from maximum external rotation to maximum internal rotation)
F: fractures of the radial head or neck Pt: arm flexed 90° / humerus, forearm, and hand on same horizontal plane / Center radial head area to center of IR, distal humerus and proximal forearm are placed "square" with, or parallel with, the borders of IR CR: perpendicular / radial head (approximately 2 to 3 cm [1 inch] distal to lateral epicondyle) Po: superimposition of epicondyles / Radial head and neck should be partially superimposed by ulna
PA and PA Axial Scaphoid—With Ulnar Deviation: Wrist
F: fractures of the scaphoid Pt: evert hand (move toward ulnar side) as far as patient can 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: scaphoid at a point 2 cm [ 0.75 inch] distal and medial to radial styloid process
PA Scaphoid—Hand Elevated and Ulnar Deviation: Wrist / Modified Stecher Method
F: fractures of the scaphoid (alternative to CR angle ulnar deviation) Po: hand elevated on 20° angle sponge or no ulnar deviation with severe pain / Scaphoid without superimposition CR: perpendicular to IR and directed to scaphoid
AP Oblique Projection—Medial (Internal) Rotation: Elbow
F: primarily the coronoid process of ulna and trochlea Pt: a natural palm-down position and rotate arm as needed until distal humerus and anterior surface of elbow are rotated 45° (place interepicondylar plane approximately 45° to the IR) Po: Radial head and neck superimposed and centered over the proximal ulna / Medial epicondyle and trochlea should appear / Olecranon process in olecranon fossa / trochlear notch partially open
AP Oblique Projection—Lateral (External) Rotation: Elbow
F: primarily the radial head and neck and capitulum of humerus. Pt: Supinate hand and rotate laterally / distal humerus and the anterior surface of the elbow joint are approximately 45° to IR. (Patient must lean laterally for sufficient lateral rotation.) Po: radial head, neck, and tuberosity, free of superimposition by ulna/ Lateral epicondyle and capitulum should appear
PA Oblique Projection—Medial Rotation: Thumb
F: same Po: Abduct thumb slightly with palmar surface of hand; it naturally places thumb in a 45° oblique position
AP Projection: Thumb
F: same Pt: Seat patient facing table, arms extended in front, with hand rotated internally to supinate thumb for AP projection Po: Internally rotate hand with fingers extended until posterior surface of thumb is in contact with IR; Immobilize other fingers
Lateromedial or Mediolateral Projections: Fingers (true lateral position)
F: same / Pt: same Po: hand in lateral position (thumb side up) with finger to be examined fully extended and centered to portion of IR being exposed; Flex unaffected fingers; long axis of finger is parallel to IR CR: PIP joint
PA Oblique Projection—Medial or Lateral Rotation: Fingers
F: same as PA Pt: same as PA Po: 45° foam wedge block, place hand in a 45° lateral oblique (thumb side up); long axis of the finger is aligned with the long axis of the IR; IP and MCP joint spaces open CR: PIP joint; Lateral for 3,4,5th digits; Medial maybe for 2nd (more painful to patient)
Trauma Axial Lateromedial and Mediolateral Projections: Elbow / Coyle Method
F: trauma to the area of the radial head or the coronoid process of ulna / when patient cannot extend elbow fully for medial or lateral oblique projections of the elbow.
.Carpal Bridge—Tangential Projection: Wrist
F; Calcification or other pathology of the dorsal (posterior) aspect of the carpal bones Pt: flex wrist until the hand and forearm form as near a 90° (right) angle CR: Angle CR 45° to the long axis of the forearm / Direct CR - midpoint of the distal forearm about 4 cm ( inches) proximal to wrist joint
anterior fat pad
Formed by superimposed coronoid and radial pads; V: only true lateral elbow; L: anterior to the distal humerus M:Trauma or infection
Barton's fracture
Fracture and dislocation of the posterior lip of the distal radius involving the wrist joint
Bennett's fracture
Fracture of the base of the first metacarpal bone, extending into the carpometacarpal joint, complicated by subluxation (partial dislocation) with some posterior displacement
Pediatric Applications
Immobilization needed; Sponges and tape are useful; sandbags with caution; provide shielding to helping parents
the forearm should not be radiographed in a pronated position (a PA projection)
It is routinely radiographed in an anteroposterior (AP) with the hand supinated, or palm up (anatomic position) to prevent superimposition of the radius and ulna
pronator fat stripe
L: 1 cm (0.25 inch) from the anterior surface of the radius M: Subtle fractures of the distal radius
supinator fat stripe (E)
L: anterior to the proximal radius M: anterior to the proximal radius
scaphoid fat stripe
L: between the radial collateral ligament and adjoining muscle tendons, lateral to the scaphoid Visualized: PA, oblique May indicate: fracture on the radial aspect of the wrist
Lateral in extension position: all fingers and metacarpals are superimposed directly for true lateral position / phalanges and metacarpals should be superimposed and extended
Lateral in flexion: Flex fingers into a natural flexed position, with thumb lightly touching the first finger; maintain true lateral position / phalanges and metacarpals should be superimposed with hand in natural flexed position
posterior fat pad (D)
Located deep within the olecranon fossa and normally is not visible on a negative elbow; M: if it is visible on a 90° flexed lateral elbow, it means joint pathologic process.
Oblique hand for metacarpals (Exception)
Not recommended for digits; metacarpals only are of interest,
Multiple Exposures per Imaging Plate
One exposure be placed centered to the imaging plate for computed radiography and digital radiography imaging systems to avoid poor processing of images; With analog (film-based) radiography, multiple images can be placed on the same imaging plate.
AP Projection—Alternate Partial Flexion: Elbow (When Elbow Cannot Be Fully Extended)
PT: elbow partially flexed Po: Obtain two AP projections - forearm parallel to IR to visualize proximal radius and ulna & humerus parallel to IR to visualize Distal humerus CR: perpendicular to IR, directed to mid-elbow joint / If patient cannot partially extend elbow and elbow remains flexed near 90°, angle CR 10° to 15° into elbow joint / If flexed more than 90°, acute flexion projection
PA Oblique Projection—Lateral Rotation: Wrist
Po: From pronated position, rotate wrist and hand laterally 45°; use support or partially flex fingers to arch hand so that fingertips rest lightly on IR / Trapezium and scaphoid should be well visualized, with only slight superimposition of other carpals on their medial aspects
PA Projection: Hand
Po: Pronate hand with palmar surface; spread fingers slightly
PA Oblique Projection: Hand
Po: Rotate entire hand and wrist laterally 45°; all digits are separated and parallel to IR; midshafts of metacarpals should not overlap; some overlap of distal heads of third, fourth, and fifth metacarpals but no overlap of distal second and third metacarpals; Excessive overlap = too much rotation; too much separation = under-rotation
"Fan" Lateral—Lateromedial Projection: Hand
Po: Rotate hand and wrist into lateral position with thumb side up; Spread fingers and thumb into a "fan" position; all digits, including the thumb, are separated and parallel to IR and that the metacarpals are not rotated but remain in a true lateral position; distal radius and ulna are superimposed; metacarpals are superimposed CR: second MCP joint
PA projection: Wrist
Po: With hand pronated, arch hand slightly to place wrist and carpal area in close contact with IR / All the intercarpal spaces do not appear open because of irregular shapes
Lateromedial Projection: Forearm
Po: true lateral position / Elbow should be flexed 90° / head of ulna being superimposed over the radius / humeral epicondyles should be superimposed / Radial head should superimpose coronoid process, with radial tuberosity demonstrated
Distal Humerus: Forearm and humerus should be directly superimposed / Medial and lateral epicondyles and parts of trochlea, capitulum, and olecranon process all should be seen in profile
Proximal Forearm: Proximal ulna and radius, including outline of radial head and neck, should be visible through superimposed distal humerus / outlines of proximal ulna and radius superimposed over humerus
Carpals (Wrist)
Proximal row (scaphoid, lunate, triquetrum, pisiform)
Part Position 1—Radial Head-Axial Lateromedial Projection
Pt: Elbow flexed 90° if possible; hand pronated CR: 45° angle toward shoulder, centered to radial head, mid-elbow joint Po: Joint space between radial head and capitulum should be open and clear / Radial head, neck, and tuberosity free of superimposition / Distal humerus and epicondyles appear distorted because of 45° angle
Part Position 2—Coronoid Process-Axial Mediolateral Projection
Pt: Elbow flexed only 80° from extended position (because >80° may obscure coronoid process) and hand pronated CR: 45° from shoulder, into mid-elbow joint Po: Anterior portion of the coronoid appears / Joint space between coronoid process and trochlea should be open and clear. / Radial head and neck should be superimposed by ulna
AP Projection: Elbow
Pt: elbow fully extended, if possible / Ask patient to lean laterally as necessary for true AP projection Po: interepicondylar plane is parallel to IR / bilateral epicondyles seen / radial head, neck, and tubercles separated or only slightly superimposed by ulna / Olecranon process in the olecranon fossa with fully extended arm / Elbow joint space appears open
For diagnostic purposes, the most important fat pads or bands are those located around certain joints of the upper and lower limbs. These fat pads are extrasynovial (outside the synovial sac) but are located within the joint capsule. Therefore, any changes that occur within the capsule itself alter the normal position and shape of the fat pads. Most often, such changes result from fluid accumulation (effusion) within the joint, which indicates the presence of an injury involving the joint.
Radiolucent fat pads are densities, slightly more lucent than surrounding structures. As it is difficult to visualize on radiographs, optimum exposure for visualization is required
Smith's fracture
Reverse of Colles fracture, or transverse fracture of the distal radius with the distal fragment displaced anteriorly
Distance
SID - 40 to 44 inches (102 to 112 cm); From the bucky tray to the tabletop, this difference is generally 3 to 4 inches (8 to 10 cm) for floating-type tabletops.
Increase Exposure With Cast
Small to medium plaster cast - Increase 5 kV to 7 kV; Large plaster cast -Increase 8 kV to 10 kV; Fiberglass cast-Increase 3 kV to 4 kV
General Radiographic Positioning Considerations
The patient's body should be moved away from the x-ray beam and the region of scatter radiation; The height of the tabletop should be near shoulder height; The bucky tray should be moved to the opposite side of the radiographic table to reduce the amount of scatter radiation produced by the bucky device.
CT (computed tomography) and MRI
To evaluate soft tissue and skeletal involvement of lesions and soft tissue injuries; Sectional CT excellent for determination of displacement and alignment relationships with certain fractures
Colles fracture
Transverse fracture of the distal radius; displaced posteriorly; an associated ulnar styloid fracture is seen in 50% to 60% of cases
Boxer's fracture
Transverse fracture that extends through the metacarpal neck; most commonly seen in the fifth metacarpal
Rheumatoid arthritis; RA (AP and lateral hand/wrist. Norgaard method can detect early signs of RA in hands / Closed joint spaces with subluxation of MCP joints / decrease)
a chronic systemic disease with inflammatory changes throughout the connective tissues; soft tissue swelling prevalent around the ulnar styloid of the wrist; Early bone erosions typically occur first at the second and third MCP joints or the third PIP joint. Rheumatoid arthritis is three times more common in women than in men
Joint effusion (AP and lateral joint / Fluid-filled joint cavity)
accumulated fluid (synovial or hemorrhagic) in the joint cavity; sign of an underlying condition, such as fracture, dislocation, soft tissue damage, or inflammation.
general positioning rule
always to place the long axis of the part being imaged parallel to the long axis of the portion of the IR being exposed; all body parts should be oriented in the same direction when two or more projections are taken on the same IR.
distal row of carpals
articulates with the five metacarpal bones; (lateral) trapezium, trapezoid, capitate, hamate (medial)
Osteochondroma (exostosis)
benign bone tumor; aged 10 to 20 years; arise from the outer cortex with the tumor growing parallel to the bone, pointing away from the adjacent joint; common at the knee but also occur on the pelvis and scapula of children or young adults.
Enchondroma
benign cartilaginous tumor; found in small bones of the hands and feet of adolescents and young adults; well-defined, radiolucent-appearing tumors with a thin cortex
Radial deviation projection
best demonstrates the interspaces and the carpals on the ulnar (lateral) side of the wrist-hamate, triquetrum, pisiform, and lunate; hamulus process of the hamate also seen
Ulnar deviation projection
best demonstrates the scaphoid without the foreshortening and overlapping seen on the posteroanterior (PA)
metacarpophalangeal (MCP) joint
between distal end of metacarpal and the proximal phalanx
Nuclear Medicine
bone scans are useful for demonstrating osteomyelitis, metastatic bone lesions, stress fractures, and cellulitis; demonstrate the pathologic process within 24 hours of onset; more sensitive than radiography because it assesses the physiologic aspect
Special Patient Considerations - Trauma Patients
can be radiographed on the table or be taken directly on the stretcher
Geriatric Applications
clear and complete instructions; may have greater difficulty in holding some of the strenuous positions required, so use adequate immobilization, may reduce exposure techniques because of certain destructive pathologies commonly seen in elderly patients, such as osteoporosis
collimation rule
collimation borders should be visible on all four sides without cutting off essential anatomy
Paget disease; osteitis deformans (AP and lateral affected area /Mixed areas of sclerotic and cortical thickening along with radiolucent lesions; "cotton wool" appearance / may increase)
common chronic skeletal disease; bone destruction followed by a reparative process of overproduction of very dense yet soft bones that tend to fracture easily; most common in men older than age 40; can occur in any bone but most commonly affects the pelvis, femur, tibia, skull, vertebrae, and clavicle
Metacarpals (Palm):
composed of Head, body or shaft, base (articulates with associated carpals)
Phalanges / phalanx (single)
consist a digit; Thumb - #1 (first), composed of two phalanges; proximal and distal phalanges; Four fingers - proximal, middle, distal phalanges; Each phalanx has head, body or shaft, base
Finger joints
distal interphalangeal (DIP) joint; proximal interphalangeal (PIP) joint; metacarpophalangeal (MCP) joint.
carpal canal or tangential projection
down the wrist and arm from the palm or volar side of a hyperextended wrist; it demonstrates the carpal sulcus formed by the concave anterior or palmar aspect of the carpals; pisiform and the hamulus process of the hamate are visualized best on this view; The relationship of trapezium, thumb, and trapezoid are well demonstrated.
triquetrum
has three articular surfaces and is distinguished by its pyramidal shape and anterior articulation with the small pisiform.
Osteopetrosis; marble bone (AP and lateral long bone / Chalky white or opaque appearance with lack of distinction between the bony cortex and trabeculae)
hereditary disease marked by abnormally dense bone; result of fracture of affected bon; lead to obliteration of the marrow space
hamate
hook-like process called the hamulus or hamular process, which projects from its palmar surface
Lunate (moon shaped)
in the proximal row, articulates with the radius; not be seen on carpal canal or tangential projection because it is distinguished by the deep concavity on its distal surface
Bursitis (AP and lateral joint / Fluid-filled joint space with possible calcification)
inflammation of the bursae or fluid-filled sacs that enclose the joints; formation of calcification in associated tendons,4 which causes pain and limited joint movement
Osteomyelitis (AP and lateral affected bone; nuclear medicine bone scan / Soft tissue swelling and loss of fat pad detail visibility)
local or generalized infection of bone or bone marrow caused by bacteria introduced by trauma or surgery; commonly the result of an infection from a contiguous source, such as a diabetic foot ulcer.
Ewing sarcoma
malignant bone tumor in children and young adults that arises from bone marrow; "onion peel" appearance on radiographs
Chondrosarcoma
malignant tumor of the cartilage; dense calcifications are often seen within the cartilaginous mass
Tumors; neoplasms, bone neoplasia (AP and lateral affected area /Appearance dependent on type and stage of tumor)
most often benign (noncancerous) but may be malignant (cancerous); CT and MRI are helpful
Osteoarthritis or degenerative joint disease (DJD) (AP and lateral affected area /Narrowing of joint space with periosteal growths on joint margins / none or decrease)
noninflammatory joint disease characterized by gradual deterioration of the articular cartilage with hypertrophic (enlarged or overgrown) bone formation; most common type of arthritis and normal part of the aging process.
carpal tunnel syndrome (PA and lateral wrist; Gaynor-Hart method. Sonography / Possible calcification in carpal sulcus Enlargement of wrist ligaments and median nerve compression)
painful disorder of the wrist and hand that results from compression of the median nerve; commonly found in middle-aged women.
carpometacarpal (CMC) joints
place where proximal metacarpals articulate with specific carpals; • First MC with trapezium • Second MC with trapezoid • Third MC with capitate • Fourth and fifth MC with hamate
Lead masking
placed on top of the IR to help prevent exposure from scatter and secondary radiation from the adjacent exposure
Osteoporosis (AP and lateral affected area / Best visibility in distal extremities and joints as decrease in bone density (brightness); long bones demonstrating thin cortex)
reduction in the quantity of bone or atrophy of skeletal tissue; occurs in postmenopausal women and elderly men, resulting in bone trabeculae that are scanty and thin
Osteogenic sarcoma (osteosarcoma)
secondary common primary cancerous bone tumor; affects persons aged 10 to 20 years but can occur at any age
Skier's thumb (PA bilateral stress projection thumbs -Folio method / Widening of inner MCP joint space of thumb and increase in degrees of angle of MCP line /ulnar collateral ligament injury)
sprain or tear of the ulnar collateral ligament of the thumb near the MCP joint of the hyperextended thumb; result from an injury such as falling which causes the thumb to be bent back toward the arm; PA stress projection of bilateral thumbs [Folio method] best demonstrates this condition
capitate
the largest of the carpal bones; large rounded head that fits proximally into a concavity formed by the scaphoid and lunate bones
Elbow Joint (3)
three significant fat pads or stripes; visualized only on true lateral projection; optimum exposure technique must be used
Bone metastases (malignant bone tumors)
transfer of disease or cancerous lesions from one organ or part that may not be directly connected through the bloodstream or lymphatic vessels or by direct extension
Lateral wrist x-ray
trapezium and the scaphoid are located more anteriorly
IR
use the smallest possible receptor size; Two or more projections may be taken on one IR when using analog (film-based) imaging, not for using digital systems
Arthrography
used to image tendinous, ligamentous, and capsular pathology associated with diarthrodial joints, such as the wrist, elbow, shoulder, and ankle; Requires the use of a radiographic contrast medium injected into the joint capsule under sterile conditions
trapezoid
wedge-shaped, four-sided, the smallest bone in the distal row.
Alternative AP wrist
wrist and carpals in close contact with IR; F: demonstrate intercarpal spaces and wrist joint better; place the intercarpal spaces more parallel to the divergent rays / good for visualizing the carpals
Elbow Routine
• AP • Alternate AP—partial flexion • Alternate AP—acute flexion • Oblique • Lateral (external) • Medial (internal) • Lateral F: Fractures and dislocations of the elbow, osteomyelitis and arthritis CR: mid-elbow joint / 2 cm ( 0.75 inch) distal to midpoint of a line between epicondyles
Digital Imaging Considerations
Grid use with digital systems (computed radiography/digital radiography); grids generally are not used with film-screen imaging for body parts measuring 10 cm or less. This is also true for computed radiography in which image plates are used. However, with direct digital radiography, grids may be used if the grid is an integral part of the IR mechanism.
This concave area or groove is called
carpal sulcus, carpal tunnel or canal; major nerves and tendons pass.
interphalangeal (IP) joint
joint between phalanges of thumb
Hand routine
PA, PA oblique, Lateral; F: Fractures, dislocations, or foreign bodies of the phalanges, metacarpals, and all joints of the hand; Pathologic processes such as osteoporosis and osteoarthritis Pt: hand and forearm extended CR: third MCP joint Co: entire hand and wrist and about 2.5 cm (1 inch) of distal forearm are visible
Wrist Routine
PA, PA oblique, lateral F: Fractures of distal radius or ulna, isolated fractures of radial or ulnar styloid processes, and fractures of individual carpal bones; osteomyelitis and arthritis; Pt: shoulder, elbow, and wrist are on same horizontal plane CR: midcarpal area Collimation: From Midmetacarpals to distal radius and ulna
Thumb X-Ray Series
PA, lateral, oblique; must include from the distal phalanx to the base of the first metacarpal (c.f.: other fingers include only distal, middle, proximal phalanges)
Lateral Position: Thumb
Po: hand pronated and thumb abducted, with fingers and hand slightly arched; then rotate hand slightly medial until thumb is in true lateral position
AP Projection: Forearm
Po: medial and lateral epicondyles are the same distance from IR / with radial head, neck, and tuberosity slightly superimposed by the ulna
1. Supinate hand (palm up) and externally rotate as far as patient can tolerate 2. Place hand in true lateral position (thumb up) 3. Pronate hand (palm down) 4. Internally rotate hand (thumb down) as far as patient can tolerate
Radial tuberosity should be visualized 1. slightly anterior 2. superimposed over radial shaft 3. slightly posterior 4. posteriorly seen
Importance of Visualizing Fat Pads
Radiographs of the upper and lower limbs are taken not only to evaluate for disease or trauma to bony structures but also to assess associated soft tissues, such as certain accumulations of fat called fat pads, fat bands, or stripes.
radius (lateral or thumb side)
ulna (medial side or pinky side)
the proximal radioulnar joint & the distal radioulnar joint
where radius and ulnar articulate; allow for the rotational movement of the wrist and hand
AP elbow
with no rotation, the proximal radius is superimposed only slightly by the ulna
AP lateral rotation elbow
The radius and ulna are separated
pisiform
the smallest of the carpal bones; anterior to the triquetrum; most evident in the carpal canal or tangential projection
bones of the upper limb divided into four main groups:
(1) hand and wrist, (2) forearm, (3) arm (humerus), and (4) shoulder girdle
Po: Tangential view of the dorsal aspect of the scaphoid, lunate, and triquetrum / utline of the capitate and trapezium superimposed is visible
CR and center of collimation field to the area of the dorsal carpal bones.
Joints of the Hand
Thumb joints
scaphoid (navicular)
a boat-shaped, largest in the proximal row, articulates with the radius proximally; most frequently fractured carpal bone.
Fracture (AP and lateral of long bones; AP, lateral, and oblique if joint involved / Disruption in bony cortex with soft tissue swelling)
a break in the structure of bone caused by a force (direct or indirect)
trapezium
a four-sided, irregularly shaped bone; medial and distal to the scaphoid and proximal to the first metacarpal.
Multiple myeloma
most common primary cancerous bone tumor; occur in various parts; arising from bone marrow or marrow plasma cells; Radiographic appearance: "punched-out" osteolytic (loss of calcium in bone) lesions; ages 40 and 70
AP medial oblique elbow
ompletely superimposes of radius and ulna
