Image Evaluation Chapter 3

Image EvaluationChapter 3 Critique of Upper Extremity

Hand (PA) • ID requirements • Marker • No preventable artifacts • Contrast & density • ? True PA • ?long axes of 3rddigit and metacarpal aligned

Hand (PA) • ? Soft tissue overlap • ? IP, MP, & CM joints open and phalanges & metacarpals not foreshortened and thumb is in 45 degree oblique position • ? 3rd MP joint in center

Hand (medial oblique) • Not enough rotation: midshafts of metacarpals are evenly spaced and metacarpal heads are not superimposed • Too much rotation: 3rd -5th metacarpal midshafts are superimposed

Hand ( medial oblique) • ? Long axes of 3rd digit and metacarpal aligned • ? Soft tissue overlap • ? IP, MP joints open and phalanges not foreshortened, thumb may be lateral or oblique • ? 3rd MP join in center

Hand ( lateromedial) • 2nd – 5th superimposed ( palpate knuckles) • If not the 2nd metacarpal is demonstrated anterior to the 3rd – 5th metacarpal and the hand is rotated internally or pronated

Hand ( lateromedial) • ? Long axes of metacarpals aligned • ? IP joints open and phalanges not foreshortened • MP joints in center • Optional Positioning: extension & flexion

Wrist ( PA) • ? True PA : styloids of radial & ulnar are lateral and medial edges of each bone; radioulnar articulation is open with minimal superimposition of metacarpal bases • Rotation is affected by hand, humerus, & elbow movements

Wrist ( PA) • If externally rotated, carpal and metacarpal are superimposed on medial side of wrist • If internally rotated, carpal and metacarpal laterally superimposes and shows more pisiform and hamate

Wrist ( PA) • If hand & wrist are rotated, the radioulnar articulation is closed • If humerus & elbow are rotated, ulna placement changes • The ulna & radius cross each other if humerus is not abducted

Wrist (PA) • ?carpal bones at center of field • Film should include carpal bones, ¼ of distal ulna and radius, and ½ of the proximal metacarpals.

Wrist ( medial oblique) • ?45 degree medial oblique • ?trapezoid & trapezium without superimposition, with trapeziotrapezoidal joint space open • ?2nd CM and scaphotrapezium joint spaces demonstrated • ?long axes of 3rd metacarpal and radius aligned

Wrist (Lateral) • ? True lateral – distal end of scaphoid & pisiform & radius with ulna superimposed • ?90 degrees • If rotated the distal scaphoid & pisiform relationship changes and the pronator fat stripe is obscured

Wrist (lateral) • If rotated externally (hand supinated) distal scaphoid is seen posterior to the pisiform • If rotated internally (hand pronated) distal scaphoid is seen anterior to the pisiform

Wrist (Ulnar-flexed) • ?ulnar flexed • ?scaphoid seen without foreshortening and long axes of 1st metacarpal and radius aligned • If patient can’t flex enough angle 20 degrees

Wrist(ulnar-flexed) • ?scaphoid in center of field • See carpal bones, radioulnar articulation & proximal 1st – 4th metacarpals on film • Scaphoid is most common fractured carpal bone

Forearm (AP) • ?long axis of forearm aligned • Forearm midshaft in center of field • wrist radius & ulna, elbow joints & forearm soft tissue seen on film • ?distal forearm in true AP- radial styloid is seen in profile laterally & very little superimposition of the metacarpal bases of ulna & radius

Forearm (AP) • ?proximal forearm in true AP • ?radial head & tuberosity superimpose lateral part of proximal ulna. If on film, the medial and lateral humeral epicondyles are seen in profile

Forearm ( lateral) • Anode heel effect- density is less at anode end of tube than cathode • So, we need to position which part of forearm at the anode end? • Soft tissue sightings – anterior & posterior fat pads and the supinator fat stripe at the elbow; pronator fat stripe at the wrist

Forearm ( lateral) • ?long axis of forearm aligned • ?midshaft of forearm at center of field • ? Wrist, radius & ulna & elbow joints and forearm soft tissue on film

Forearm ( lateral) • Proximal forearm & distal humerus positioning: • Elbow flexed 90 degrees – poor elbow positioning obscures fat pads that we need to see for diagnosis • The radial tuberosity is superimposed by the radius and is not seen in profile • Distal humerus in true lateral position

Elbow ( AP) • ? True AP projection • Medial & lateral humeral epicondyles are seen in profile • Detecting elbow rotation(1)epicondyles no seen in profile(2)radial head & tuberosity are seen with more than slight superimposition of the ulna(3)coronoid is seen in profile

Elbow (AP) • ?radial tuberosity medially in profile & eliminates crossing of the radius & ulna • Capitulum-radius joint is open • When patient can’t extend elbow; ap proximal forearm& ap distal humerus

Elbow (medial & lateral oblique) • ?capitulum-radial joint open • ?elbow joint at center of field • ?elbow joint, ¼ proximal forearm, distal humerus on film • Medial oblique: 45 degrees medially • Coronoid process, trochlear notch & medial aspect of trochlea in profile • Trochlear-coronoid joint is open with superimposition of radial head & neck over ulna

Elbow(medial & lateral oblique) • Lateral oblique: 45 degrees laterally • ?captitulum & radial tuberosity are seen in profile • ?radial head, neck, and tuberosity seen without superimposing ulna & radioulnar joint is seen

Elbow (lateral) • Posterior fat pad is not usually seen unless there is injury • Displacement of supinator fat stripe could mean fractures of radial head and neck • Change in shape or placement of anterior fat pad may indicated joint effusion & elbow injury

Elbow (lateral) • ?elbow flexed 90 degrees • ? True lateral position • ?elbow joint space is open and radial head superimposes coronoid process • ? Radial tuberosity superimposed by radius and not seen in profile • ?elbow joint in center of field

Humerus(AP) • ?true AP • ?long axis aligned • ?midshaft of humerus in center of film • ?shoulder and elbow joints & lateral humeral soft tissue on film

Humerus (lateral) • ?mediolateral • ?lateromedial • ?long axis aligned • ?midshaft in center of field

Image Evaluation Chapter 3