‹ Back to all protocols

CT Lower Extremity (Hip/Knee/Ankle/Foot)

CTNo contrastMSK

Indications

Complex/occult fracture (tibial plateau, calcaneus, talus, pilon, acetabulum)
Intra-articular fracture characterization, fracture-dislocation, nonunion, hardware
Preoperative and reduction planning; tarsal coalition

Patient prep

Remove metal, jewelry, removable braces
Immobilize part; bilateral comparison sometimes requested
No contrast for routine osseous indication

Contrast

None / non-contrast

Technique

Supine, feet first; affected limb centered; foot/ankle dorsiflexed/neutral as feasible
Knee: supine, leg extended; ankle/foot: supine knees bent or extended depending on reformats needed
120 kV, dose modulation; sub-mm collimation, isotropic recon
Bone and soft tissue algorithms; align coronal/sagittal to the joint
3D reformats for surgical planning (e.g., calcaneus, tibial plateau)

Series / Sequences

#	Series / Sequence	Plane	Thickness	Notes
1	Axial bone	axial	0.5-1 mm	Bone kernel
2	Coronal reformat	coronal	0.5-1 mm	Aligned to joint
3	Sagittal reformat	sagittal	0.5-1 mm	Aligned to joint
4	3D VR	3D	VR	Articular surface/surgical planning

Key points

Align reformats to the joint (e.g., subtalar joint for calcaneus, plateau for tibia)
Tibial plateau and calcaneal fractures particularly benefit from CT for surgical classification (Schatzker, Sanders)
Use MAR recon for orthopedic hardware
Soft tissue windows for compartment, foreign body, abscess
CT arthrogram option when MRI contraindicated

References

• ACR-SSR Practice Parameter for the Performance of CT of the Extremities
• Radiopaedia: calcaneal fracture ( link
• ACR Appropriateness Criteria: Acute Trauma to the Foot/Ankle/Knee

Source: Researched — verify against your institution

‹ PreviousUltrasound Abdominal Aorta (AAA Screen)Next ›CT Upper Extremity (Shoulder/Elbow/Wrist/Hand)

Reference template — verify and adapt to your scanner, vendor and institution before clinical use. Not a substitute for clinical judgment.