Scaphoid, Forearm and Elbow Flashcards
When working with angles what must you check?
The SID
What is the scaphoid?
- the largest carpal in the proximal row
- anterior and lateral tubercles
- palpable near the base of the thumb
- “anatomical snuffbox”
What is the carpal canal?
- bony passageway for the median nerve and flexor tendons to pass through
- goes through the carpals and the flexor retinaculum
- compression of the median nerve causes carpal tunnel syndrome
What is the elbow?
- articulation of the humerus with the radius and ulna
- distal humerus has two condyles (trochlea and capitulum)
- epicondyles are the medial and lateral protuberances above
- distal humerus has 2 fossae (olecranon and coronoid)
- 2 fat pads seen on the lateral projection
Scaphoid - PA Projection
position - hand prone in ulnar deviation
CR - perpendicular to IR
CP - scaphoid
collimation - base of 1st metacarpal to ulnar head
Scaphoid - PA Axial Projection
Position - hand prone in ulnar deviation
CR - 20 degrees proximally
CP - Scaphoid
collimation - base of 1st metacarpal to ulnar head
Scaphoid - Alternate PA Axial Projection
Position - hand prone in ulnar deviation - hand elevated on a 20 degree sponge
CR - perpendicular to IR
CP - Scaphoid
collimation - base of 1st metacarpal to ulnar head
Scaphoid - PA and PA Axial Evaluation Criteria
- distal radius and ulna to proximal half of meta carpals
- scaphoid and adjacent joint spaces open
- axial method should show scaphoid freer from superimposition
- no rotation
- ulnar deviation
- see boney trabeculae and soft tissue
What is the scaphoid series?
Rafert-Long method
4 images
PA and PA axial with angles of 10, 20 and 30
Tangential carpal canal projection
- hyperextend wrist
- slight radial rotation (flattens carpal canal)
CR - 25-30 proximally
CP - Palm of the hand, include all of the canal - styloids to centre of IR
Tangential carpal canal evaluation criteria
- carpals are in an arch
- pisiform separate and in profile
- hook of hamate
- common athletic injuries can be diagnosed with this projection: hook of hamate, pisiform and trapezium
Forearm - AP Projection
3 major joints must be on the same plane (wrist, elbow and shoulder)
- arm supinated, ensure elbow and wrist are true AP - epicondyles equidistant
CR - perpendicular
CP - middle of forearm
collimate 5cm or 2in past each joint
Forearm - AP Evaluation Criteria
- entire forearm and both end joints
- slight superimposition of proximal radius/ulna
- no elongation/foreshadowing of humeral epicondyles
- partially open wrist and elbow joints
- open radioulnar space
Forearm - lateral projection
3 joints on same plane, arm bent 90, wrist and lateral in true lateral best you can
CR - perpendicular
CP - middle of forearm
Collimate 5cm or 2in past each joint
Forearm - lateral evaluation criteria
- entire forearm and both end joints
- superimposition of distal radius/ulna
- superimposition of radial head and coronoid process
- superimposed humeral epicondyles
- radial tuberosity facing anteriorly
What projections do you start hanging in anatomical position?
elbow