Xray Positioning: Hand PA

Hand PA Positioning for Rad Tech Students

 

Name of projection Hand – PA
Area Covered Hand, wrist, and 2.5cm of distal forearm
Pathology shown Fractures, dislocations, foreign bodies. Pathological processes – osteoporosis and osteoarthritis.
Radiographic Anatomy Hand Radiographic Anatomy
IR Size & Orientation 24 x 30cm
Landscape, divided in half usually fits 2 projections, use lead masking for an unused area
Film / Screen Combination Detail
(CR and DR as recommended by the manufacturer)
Bucky / Grid No
Filter No
Exposure 50 kVp
2.5 mAs
FFD / SID 100cm
Central Ray Directed to 3rd metacarpophalangeal joint
Perpendicular to the IR
Collimation Centre: 3rd metacarpophalangeal joint
Shutter A: Includes all of the distal phalanges to 2.5cm of the distal ulna and radius
Shutter B: To include soft tissues
Markers Distal and Lateral
Marker orientation AP
Shielding Gonadal (check your department’s policy guidelines)
Respiration Not applicable
Positioning
  • Patient seated at end of the table
  • Elbow flexed to 90°
  • Hand pronated
  • Hand and forearm resting on the table
  • Place IR under the hand
  • Palm in contact with IR
  • Fingers spread slightly
  • Centre to 3rd metacarpophalangeal joint
  • Critique
  • PACEMAN
 Positioning

  • Digits and metacarpals are demonstrated in the PA projection by
    1. Uniformity of the soft tissue of digits two through to 5
    2. Metacarpal heads are equally spaced for digits two through to five
    3. Equal concavity of the midshaft of the phalanges and metacarpals of digits two through to five
  • No soft tissue overlap of the digits
  • The following joint spaces are open
    1. Interphalangeal
    2. Metacarpophalangeal
    3. Carpometacarpal
  • The long axis of hand is aligned with the axis of IR
  • Thumb is demonstrated at a 45º angle

Area Covered

  • Entire hand, carpals and 2.5cm of the distal radius and ulna

Collimation

  • Outer skin margins of hand on four sides and including 2.5cm of the distal forearm

Exposure

  • Bony trabecular patterns and cortical outlines are sharply defined
  • Soft tissues are visualized
Special Notes Effect of flexion of the hand
If the palmar surface of the hand is not placed against the surface of the IR, this results in poor alignment of the joint space with the central ray. This results in closed joint spaces and foreshortening of phalanges and metacarpals