Positioning & Parameters

PA Chest positioning

• Facing bucky

• Hands on hips or around bucky, shoulders forward, chin raised, chest in contact with the board.

• Lightbeam/detector 3cm above shoulder edge.

• Centre on T7 (base of shoulder blade).

PA Chest Parameters

• Large detector and broad focal spot.

• 180-200cm SID.

• 110-125kVp (higher for denser/larger patients).

• 2-6mAs OR AEC.

  • If using AEC, select the two lateral chambers, NOT middle.

• Marker top corner (R/L does not matter, choose one).

• Inspiration.

• No annotation as PA is convention.

PA variations (seated): Holding detector & sitting against detector

AP Erect Chest Positioning

• Sitting upright in bed or wheelchair.

• Chin raised, arms to patient’s side (arms on bed rails is good, gets scapulae out of way), IR against patient’s back.

• Bending at hinge point (hips).

• Top Border C7.

• 10-15° caudal (downwards angulation).

• CENTRAL RAY at T7.

AP Erect Chest Parameters

• Large (35cm x 43cm detector), broad focal spot.

• 180cm SID.

• 90-100kVp

• 1-5mAs

• Marker top corner (R/L your choice).

• Annotated to denote AP/erect/semi-erect

• Inspiration.

AP Supine Chest Positioning

• Lying on their back on bed.

• Chin raised, arms by sides.

• IR behind patient’s back or in table bucky.

• Top border C7.

• 10-15° caudal angulation (to sternum).

• Central Ray approx. T7.

AP Supine Chest Parameters.

• Large detector, broad focal.

• 180cm SID.

• 90-100kVp.

• 1-5mAs.

• Top corner marker.

• Annotated to denote AP/supine.

• Inspiration.

Lateral Chest Positioning

• Patient’s left side against bucky.

• Shoulder in contact with bucky, hands on head or holding handlebar.

• Centre T7 on mid-auxillary line (base of shoulder blade).

Lateral Chest Parameters

• Large detector PORTRAIT.

• Broad focal spot.

• 180-200cm SID.

• 100-125kVp.

• 8-20 mAs or AEC.

  • For AEC: single central chamber.

• Marker on anterior corner (R/L).

• Inspiration.

Decubitus Chest Positioning

• Patient lying on their side.

• Will show like a PA/AP projection.

• Side down for pleural effusion.

• Side up for pneumothorax.

• Can be lateral (top left pictures) or supine (bottom).

ABCS of Image Interpretation

• Alignment.

• Bones.

• Cartilage.

• Soft tissue.

ABCDE of Chest X-rays

• Airway.

• Breathing.

• Circluation.

• Deformities.

• Everything Else.

PA Finger Positioning

• Finger of interest aligned parallel to edge of IR.

• Hand palm down (pronated) on IR with fingers straight (ensure open joint spaces).

• CR perpendicular to IR, collimate to digit including skin edge and Metacarpal in collimation.

• CR over proximal phalanx.

PA/Oblique/lateral Finger Parameters

• Small (18cm x 24cm) detector.

• 100cm SID.

• 50-55 kVp.

• 1-2 mAs.

• FINE focus.

• Marker positioned distal to main anatomy.

Oblique finger positioning

• Finger of interest aligned parallel to edge of IR.

• From PA position, rotate (supinate) hand and wrist 45° (radial aspect raised).

• CR perpendicular to IR, collimate to digit including skin edge and MC in collimation.

• CR over proximal phalanx.

Lateral Finger Positioning

• Finger of interest aligned parallel to IR edge.

• Hand perpendicular to IR.

  • 2nd digit: Radial aspect in contact with IR (if patient comfort allows).

  • 3rd-5th digit: ulnar aspect in contact with IR.

• Fold/extend other digits out of superimposition.

• CR perpendicular to IR, collimate to digit including skin edge and MC in collimation.

• CR over proximal phalanx.

AP/PA Thumb positioning

• Thumb aligned parallel to IR edge.

• Hand perpendicular to IR, thumb relaxed and parallel to IR.

• CR perpendicular to IR, collimate to thumb including skin edge and carpometacarpal joint.

Oblique Thumb positioning

• Hand palm down on contact with IR.

• CR perpendicular to IR, collimate to thumb including skin edge and carpometacarpal joint.

Lateral Thumb positioning

• Hand tented, in fist, or raided on sponge to raise ulnar aspect.

• CR perpendicular to IR, collimate to thumb including skin edge and carpometacarpal joint.

• CENTRE OVER MCP Joint.

Thumb parameters

• Small detector.

• SID 100cm

• 50-55 kVp.

• 1-2 mAs.

• Increase SID, kVp and mAs for PA - air gap with increased OID.

• Fine focus.

• Distal Marker.

PA hand positioning

• 3rd digit aligned parallel to edge of IR.

• Fingers straight, slightly spread, and parallel to IR.

• CR perpendicular to IR, collimate to include skin edge distally and 1-2cm of radius and ulna proximally.

• Center at 3rd MCP joint.

Oblique hand positioning

• Supinate/rotate hands & wrist 30-45 degrees (radial aspect raised.

• Fingers straight and parallel to IR, support with sponge.

Lateral hand positioning

• Hand perpendicular or IR, ‘ok sign’ or stacked/superimposed.

• Fingers straight, supported by sponge.

Hand Parameters

• Medium (24cm x 30cm) detector.

• SID 100cm.

• kVp 50-55 (up to 60 for lateral).

• 1-3 mAs (up to 3 for lateral).

• Fine focus.

• Marker lateral or anterior - distal OR proximal.

Ballcatcher’s (norgaard) view

• Collimate to include both hands and wrists.

• CR level with 5th MCP joint.

Brewerton hand view

Wrist series

Wrist parameters

• medium (24cm x 30cm) detector.

• 100cm SID.

• 50-55kVp.

• 2-3 mAs.

• Fine focus.

• Lateral or anterior marker.

Scaphoid view

• PA wrist with ulnar deviation.

• Centre to anatomical snuffbox.

PA axial with ulnar deviation: Stecher view.

• Position as above, but with cephalic angle of 15-30 degrees.

AP and AP Oblique wrist

AP Oblique → radial aspect raised 45 degrees from AP.

Carpal tunnel view

• CR 25-30 degrees to long axis of hand.

• Centre to middle of palm.

forearm AP positioning

• Aligned parallel to long edge of IR or diagonally across IR.

• Hand palm up on IR with arm in full extension.

• Hand, elbow, and shoulderin same horizontal plane.

• CR perpendicular to IR.

• Collimate to include both joints in fiend and include skin edge laterally.

AP Forearm parameters

• Large (35×43) detector.

• SID 100cm

• 55-60 kVp.

• 2-5 mAs.

• FIne.

• Marker distal and lateral.

Lateral forearm positioning

• Forearm aligned parallel to long edge IR or diagonal.

• Hand/Wrist and elbow in ‘true lateral’.

  • Elbow flexed 90 degrees.

  • Distal radius and ulna superimposed.

  • Humeral epicondyles superimposed (raise wrist to help achieve this).

• Hand elbow and shoulder on same horizontal plane.

• CR perpendicular to IR.

• Collimate for both joints and 5-8cm of distal humerus.

Plan B forearms

• For when patient has limited ROM

• AP elbow + lateral wrist (top).

• Lateral elbow with PA wrist (bottom).

horizontal beam lateral elbow/forearm positioning

• Patient has extremely limited ROM.

• Support anatomy on radiolucent sponge.

• Arm parallel to IR, tube perp. to IR.

AP elbow positioning

• Long axis of elbow parallel to edge of IR.

• Elbow in full extension and palm up → humeral epicondyles equidistant to IR.

• Hand, elbow, and shoulder on same horizontal plane.

• 8-10cm of prox. forearm and distal humerus included.

• Centre at cubital fossa.

AP/AP oblique elbow parameters

• 100cm SID

• 55-60 kVp.

• 2-5 mAs.

• Fine focus.

• Lateral or distal marker.

AP external oblique elbow positioning

• Long edge elbow parallel long edge IR.

• Start in AP position then rotate arm externally so epicondyles are 30-35 degrees oblique to IR (patient might need to lean back to aid it).

• Hand, elbow, and shoulder still on same horizontal plane.

• No angle on CR (perp. to IR).

• Collimate to include both 8-10cm of proximal forearm and distal humerus.

• Centre at cubital fossa.

Lateral elbow positioning

• Hand wrist and elbow in “true lateral.”

• Distal radius and ulna superimposed.

• Humeral epicondyles superimposed (raise wrist to help).

• CR perp to IR, centre to JOINT.

• 8-10cm of both distal humerus and proximal forearm.

radial head (coyle’s view) positioning

• Start in lateral position.

• Pronate hand.

• CR angled 35-45 degrees proximally (towards head/up the arm).

• Collimate in closer to ROI.

Reverse Coyle’s positioning (coronoid process view).

• Same position as radial head view, reduce elbow flexion to 80 degreesish.

• CR angled 35-45 degrees DISTALLY (away from shoulder).

AP internal oblique positioning (coronoid process view)

• Start in AP elbow position.

• Pronate hand to palm down.

• No angle on CR (perp. to IR).

acute flexed axial positioning

AP Toes Positioning

• Patient lying or sitting on table.

• Bent knee, sole of foot perpendicular to IR.

• Foot’s long axis parallel to IR’s edge, toes UNCURLED.

• CR angled 10-15 degrees posteriorly (towards calcaneus).

• Centre to MTP joint.

• Collimate for skin edges distally and MT base proximally.

Oblique (internal) toe (1st-3rd toe)

• Long axis of foot parallel to IR.

• Start AP toes, rotate 30-40 degrees internal.

• CR perpendicular to IR.

• Centre at MTP joint of interest.

• Collimate for skin edge distally and MT base proximally.

• Include part of toes either side.

Oblique (external) toe

• Start AP toe, rotate 30-40 degrees EXTERNAL.

• CR perp. to IR.

• Centre at MTP joint we want.

• Include MT base proximal and include part of toes either side laterally.

Lateral toes positioning

• Rotate leg MEDIALLY for 1st-3rd toes and LATERALLY for 4th and 5th toes.

• Long axis of foot parallel to IR, ensure toe of interest is true lateral position.

• Use tape or radiolucent aids to separate toes (improvise).

• CR perp. to IR.

• Include MT base proximally.

(additional) sesamoidal/tangential

• Foot dorsiflexed.

• Patient prone with toes flexed on IR.

• OR patient supine and have aids to hold toes back/keep them flexed.

AP Foot positioning

• Patient sitting or lying on table, knee bent, sole of foot flat on IR.

• Long axis of foot parallel to IR edge.

• CR angled 5-15 degrees posterior (depending on foot arch).

• Centre at BASE OF 3rd MT.

• Collimate for skin edge of TOES AND HEEL.

AP (DP) foot parameters

• Medium (24×30) IR.

• 52-60kVp (on thicker side, go 55-60ish).

• 2-5 mAs.

• Fine focus.

• Use filter (maybe) for more even exposure.

Oblique foot positioning

• From AP position rotate foot 30-40 degrees medially.

  • Use sponges to assist if necessary.

• CR perp. to IR.

• Centre at BASE OF 3RD MT.

• Include edges of toes and heel.

Oblique foot parameters

• 55-60 kVp.

• Fine focus.

• 2-5 mAs.

• MARKER DISTAL.

Lateral foot positioning

• Carefully dorsiflex foot.

• Might need 15 degree sponge under toes to ensure no over-rotation.

• Centre at TARSOMETATARSAL JOINT.

Axial calcaneus positioning

• Patient sitting or lying on table with leg extended out front.

• Long axis of leg aligned parallel to long axis of IR.

• Dorsiflexed foot, plantar surface is perpendicular to IR.

• Angle CR 40 degrees cephalad.

• CR centred on base of 3rd MT.

• Include skin edge of heel and lateral and medial skin edges of foot.

Axial calcaneus parameters

• small detector.

• 100cm SID.

• 60-65+kVp.

• 5-8 mAs.

• Fine.

• Distal marker.

lateral calcaneus positioning

• Patient’s knee flexed with externally rotated leg.

• Dorsiflex foot.

• Plantar surface perpendicular to IR.

• Collimate to skin edge of heel, ankle joint, and anterior articulation of calcaneus.

• CR 2-2.5cm distal to medial malleolus.

Lateral calcaneus parameters

• 100cm SID.

• 55-65kVp.

• 3-5 mAs.

• Fine.

• Distal marker.

Subtalar joint + sinus tarsi positioning

• externally rotate from lateral position by supporting heel.

• CR angled 5 degrees anterior and 25 degrees caudal.

  • Used to visualise changes in pes planus and/or hindfoot valgus.

AP ankle positioning

• Patient sitting or lying on table with leg extended out front.

• Dorsiflex foot so plantar aspect of foot is perpendicular to IR.

• CR perp. to IR centred between malleoli and at level of malleoli.

• Include distal 1/3 of tibia.

AP, mortise, and lateral ankle parameters

• 100cm SID.

• 55-65kVp.

• 3-5mAs.

• Fine.

• Distal marker.

Mortise ankle positioning

• Patient sitting or lying on table with leg extended out front.

• From AP position, rotate internally around 10-15 degrees AT THE FEMUR so malleoli are equidistant from IR.

• CR perp to IR, at level of malleoli and between malleoli.

• Collimate for skin edges, include distal 1/3 of tib+fib.

Lateral ankle positioning

• Knee flexed with leg externally rotated.

• Dorsiflex foot with plantar surface perpendicular to IR.

• Superimpose malleoli.

• CR perp. to IR, centre over medial malleolus.

• Collimate for skin edge posteriorly, midfoot anteriorly, and distal 1/3 of tib+fib.

Internal oblique ankle positioning

• From AP position rotate leg 45 degrees internal.

  • Used to assess syndesmosis (freeing it of superimposition) and inferior talus.