Musculoskeletal CT
Table of Contents
General Instructions 3
Ankle 4
Bony Pelvis/Acetabulum 5
Elbow 6
Foot 7
Growth Plate 8
Heterotopic Ossification 9
Hip 10
Knee 11
Patellar Tracking 12
Scapula 13
Shoulder 14
Wrist 15
General Instructions
1. All studies should be performed helically.
2. The helices should overlap by 1 slice thickness.
3. When "retro"ing the images, all parameters should remain constant (i.e., DFOV and centering).
4. The retro images should be sent to the Advantage Workstation for the radiologist to reformat. The radiologist will then send the reformatted images back to the scanner for filming.
5. In general, axial bone windows should be filmed from the Retro images with bone algorithm, and soft tissue windows should be filmed from the standard images.
6. These protocols are not all-inclusive and may not be appropriate for every case. If there is any uncertainty as to how to perform the study, please ask the radiologist for advice.
ANKLE
Positioning: Anatomical
position (dorsiflexion)
Coverage: 2 cm above
tibial plafond to bottom of calcaneus or specific area of interest
Scan: Slice
thickness: 3 mm
Pitch: 1
SFOV: Large (48 cm)
DFOV: 18 cm
Algorithm: STD
Retro: Interval: 1 mm
DFOV: 18 cm
Algorithm: Bone
Reformat: Spacing: 3 mm
Planes: Coronal, sagittal (in axis of
specified bone; if uncertain of appropriate oblique axis, please ask
radiologist to reformat)
FOV: 12-18 cm (as appropriate)
Filming: Plane Window Format Images Filmed
Axial Bone 12
on 1 Every
third Retro
Axial Soft Tissue 20
on 1 All
Coronal Bone 20 on 1 All
Sagittal Bone 20 on 1 All
BONY PELVIS / ACETABULUM
Coverage: Iliac crest to
ischial tuberosity (if pelvic fracture)
Acetabulum
only (if acetabular fracture only)
Scan: Slice
thickness: 5 mm (3 mm if acetabular
fracture)
Pitch: 1
SFOV: Large (48 cm)
DFOV: As necessary to include skin
(18
cm if acetabulum only)
Algorithm: STD
Retro: Interval: 1 mm
DFOV: 18 cm and 48 cm
Algorithm: STD
Reformat: Spacing: 5 mm (3 mm if acetabular
fracture)
Thickness: Can ≠ if grainy images
Planes: Coronal, sagittal (Try both FOVs
and use the better images. If using a
large FOV, magnify the reformats.)
3D Reconstruction: As per M.D. (For comminuted acetabular fracture. Use large FOV images and magnify.)
Filming: Plane Window Format Images Filmed
Axial Bone 12
on 1 Every
5th (or 3rd) Retro (small FOV)
Axial Soft Tissue 20
on 1 All
Coronal Bone 20
on 1 All
Sagittal Bone 20 on 1 All
3D 6
on 1 As
per M.D.
ELBOW
Positioning: Prone
with elbow extended above head, if possible
Coverage: Supracondylar
region of humerus to 2 cm distal to radiocapitellar
joint
Scan: Slice
thickness: 1 mm
Pitch: 1
SFOV: Large (48 cm)
DFOV: 18 cm
Algorithm: STD
Retro: Interval: 1 mm
DFOV: 18 cm (Use 48 cm FOV in addition
if elbow at patient's side)
Algorithm: Bone (STD if at patient's side)
Reformat: Spacing: 2 mm
Planes: Coronal, sagittal (Must be obliqued appropriately.
Have MD do reformats if needed)
Filming: Plane Window Format Images Filmed
Axial Bone 12
on 1 Every other Retro
Axial Soft Tissue 20
on 1 Every other
Coronal Bone 20 on 1 All
Sagittal Bone 20 on 1 All
FOOT
Positioning: Foot
flat on table, if possible (coronal scan)
Coverage: Area of
interest
Scan: Slice
thickness: 1 or 3 mm (depending on size
of coverage area)
Pitch: 1
SFOV: Large (48 cm)
DFOV: 18 cm
Algorithm: STD
Retro: Interval: 1 mm
DFOV: 18 cm
Algorithm: Bone
Reformat: Spacing: 2 mm
Planes: Axial, sagittal (obliqued through area of interest)
FOV: 12-18 cm (as appropriate)
Filming: Plane Window Format Images Filmed
Coronal Bone 12 on 1 Every
other Retro
Coronal Soft Tissue 20 on 1 Every
other
Axial Bone 20
on 1 All
Sagittal Bone 20 on 1 All
GROWTH PLATE (for Bony Fusion)
Coverage: Growth plate
Scan: Slice
thickness: 1 mm
Pitch: 1
SFOV: Large (48 cm)
DFOV: 18 cm
Algorithm: STD
Retro: Interval: 1 mm
DFOV: 18 cm (or smaller if
appropriate)
Algorithm: Bone
Reformat: Spacing: 2 - 3 mm (depending on size of
joint)
Planes: Coronal, sagittal
FOV: 12-18 cm (as appropriate)
Filming: Plane Window Format Images Filmed
Axial Bone 12
on 1 Every other Retro
Axial Soft Tissue 20
on 1 Every other
Coronal Bone 20 on 1 All
Sagittal Bone 20 on 1 All
HETEROTOPIC OSSIFICATION (Any Joint)
Coverage: Area of
heterotopic bone
Scan: Slice
thickness: 3 mm for elbow, 5 mm for hip or
shoulder
Pitch: 1
SFOV: Large (48 cm)
DFOV: 18 cm
Algorithm: STD
Retro: Interval: 1 mm
DFOV: 18 cm and 48
cm
Algorithm: STD
Reformat: Spacing: 3 mm for elbow, 5 mm for hip or
shoulder
Thickness: Can ≠ if grainy
images
Planes: Coronal, sagittal
FOV: As small as appropriate
3D Reconstruction: As per M.D. (Use large FOV as needed)
Filming: Plane Window Format Images Filmed
Axial Bone 12
on 1 Every
3rd or 5th Retro (small FOV)
Coronal Bone 20 on 1 All
Sagittal Bone 20 on 1 All
3D 6
on 1 As
per M.D.
Soft tissue windows
not needed.
HIP
Coverage: Acetabular roof
to subtrochanteric region of femur
Scan: Slice
thickness: 3 mm
Pitch: 1
SFOV: Large (48 cm)
DFOV: 18 cm
Algorithm: STD
Retro: Interval: 1 mm
DFOV: 18 cm and
48cm
Algorithm: STD
Reformat: Spacing: 3 mm
Thickness: Can ≠ if grainy images
Planes: Coronal, sagittal
Filming: Plane Window Format Images Filmed
Axial Bone 12
on 1 Every
third Retro (small FOV)
Axial Soft Tissue 20
on 1 All
Coronal Bone 20 on 1 All
Sagittal Bone 20 on 1 All
KNEE
Coverage: 1 cm above
patella to 2 cm below tibial plateau
Scan: Slice
thickness: 3 mm
Helical pitch: 1
SFOV: Large (48 cm)
DFOV: 18 cm
Algorithm: STD
Retro: Interval: 1 mm
DFOV: 18 cm and
48cm
Algorithm: Bone
Reformat: Spacing: 3 mm
Planes: Coronal, sagittal
Filming: Plane Window Format Images Filmed
Axial Bone 12
on 1 Every
third Retro (small FOV)
Axial Soft Tissue 20
on 1 All
Coronal Bone 20 on 1 All
Sagittal Bone 20 on 1 All
PATELLAR TRACKING
Positioning: Supine
with knees absolutely symmetrical
Coverage: Scout: Lateral (must be repeated for each position)
Top of
patella to tibial plateau at 0 degrees of flexion
Additional
images: 15, 30, 45 and 60 degrees of
flexion
5
slices only through mid-patella for each position
Scan: Slice
thickness: 3 mm
Pitch: 1
SFOV: Large (48 cm)
DFOV: Include both knees
Algorithm: STD
Retro: (Only for
images at full extension)
Interval: 1 mm
DFOV: 18 cm
Algorithm: Bone
Reformat: Spacing: 3 mm
Planes: Sagittal
Filming: Plane Window Format Images Filmed
Axial Bone 12
on 1 Every
third Retro
Axial Bone 12
on 1 All
flexion images
Axial Soft Tissue 20
on 1 Full extension only
Sagittal Bone 20 on 1 All
SCAPULA
Coverage: Entire scapula
Scan: Slice
thickness: 3 mm (or 5 mm if too many
slices for tube)
Helical pitch: 1
SFOV: Large (48 cm)
DFOV: 24 cm
Algorithm: STD
Retro: Interval: 1 mm
DFOV: 24 cm and
48cm
Algorithm: STD
Reformat: Spacing: 3 mm - coronal oblique, 5 mm -
sagittal oblique
Thickness: Can ≠ if grainy images
Planes: Coronal oblique and sagittal
oblique. (In plane of
scapula. Have MD do reformats if
uncertain of plane).
FOV: Can Ø as
appropriate
Filming: Plane Window Format Images Filmed
Axial Bone 12
on 1 Every
third Retro (small FOV)
Axial Soft Tissue 20
on 1 All
Coronal oblique Bone 20
on 1 All
Sagittal oblique Bone 20
on 1 All
SHOULDER
Positioning: Arm at
side with thumb up (neutral position)
Place
contralateral arm above head if possible
Coverage: Top of acromio-clavicular joint to 1 cm below glenoid
Scan: Slice
thickness: 3 mm
Helical pitch: 1
SFOV: Large (48 cm)
DFOV: 18 cm
Algorithm: STD
Retro: Interval: 1 mm
DFOV: 18 cm and
48cm
Algorithm: STD
Reformat: Spacing: 3 mm
Thickness: Can ≠ if grainy images
Planes: Coronal oblique (perpendicular
to glenoid)
Sagittal
oblique (parallel to glenoid)
Filming: Plane Window Format Images Filmed
Axial Bone 12
on 1 Every
third Retro (small FOV)
Axial Soft Tissue 20
on 1 All
Coronal oblique Bone 20
on 1 All
Sagittal oblique Bone 20
on 1 All
WRIST
Positioning: Prone with arm extended above head, volar aspect of wrist on
table, and fingers extended. Consider scanning both wrists together (check
with MD).
Coverage: 1 cm proximal
to radiocarpal joint to 1 cm distal to metacarpal bases (or specific area of
interest)
Scan: Slice
thickness: 1 mm
Helical pitch: 1
SFOV: Large (48 cm)
DFOV: 18 cm
Algorithm: STD
Retro: Interval: 1 mm
DFOV: 12 cm
Algorithm: Bone
Reformat: Spacing: 2 mm
Planes: Coronal, sagittal
FOV: 8-12 cm (as appropriate)
Filming: Plane Window Format Images Filmed
Axial Bone 12
on 1 Every other Retro
Axial Soft Tissue 20
on 1 Every other
Coronal Bone 20 on 1 All
Sagittal Bone 20 on 1 All