PROTOCOLS
A Check the clinical indication and choose the correct protocol
B Read any scanning notes to ensure correct positioning and orientation
C Perform the sequences in the order indicated - this is important to ensure a diagnosis in the event the scan is abandoned
D Requests for both 'Ankle and Foot' are usually not indicated. Try to use either Hind/Mid or Mid/Forefoot protocols for best resolution
Protocols are available for
• TRAUMA & ACUTE INJURY eg Twisted ankle Ankle Ligaments or Syndesmosis injury
• ANKLE or HIND/MIDFOOT eg for OA Pain, Hindfoot tendons, Tib Post Plantar fasciitis
• Coalition
• Achilles tendon
• MID/FOREFOOT eg for midfoot OA Stress fracture Pain
• FOREFOOT for Mortons neuroma Plantar plate Sesamoids
IMPORTANT SCANNING NOTES
• HIND/MIDFOOT COVERAGE Axial: Distal 3cm of tibia to below fat pad. Coronal just anterior to TMTJ's to behind retroachilles fat. Sagittal: Skin to skin.
• MID/FOREFOOT COVERAGE Coronal just posterior to TMTJ's to tip of toes. Sagittal& Axial: Skin to skin.
• Slice thickness 3mm or better FOV 12-14cm unless otherwise stated
• FSPD (fat saturated proton density) requires a TE of greater than 40ms **
• For dedicated forefoot protocols see scanning parameters below
TRAUMA & ACUTE INJURY eg Twisted ankle Ankle Ligaments or Syndesmosis injury
• Sagittal STIR
• Axial FSPD
• Coronal FSPD
• Sagittal T1 isotropic VIBE
• Coronal T1 Drive / Restore
• Axial T1
• Tilted axial FSPD along tib fib ligament see Figure opposite
ANKLE or HIND/MIDFOOT eg for OA Pain, Hindfoot tendons, Tib Post Plantar fasciitis
• Sagittal STIR
• Axial FSPD
• Coronal FSPD
• Sagittal T1
• Coronal T1 Drive / Restore
• Axial T1
Coalition
• Sagittal STIR
• Axial FSPD Tilted as per image 2 opposite
• Coronal FSPD Tilted as per image 3 opposite
• Sagittal T1
• Coronal T1 Drive / Restore
• Axial T1
Achilles tendon
• Sagittal STIR 20 cm FOV
• Sagittal T1 20 cm FOV
• Axial STIR include any abnormal area in Achilles tendon
• Axial T1
• Coronal FSPD
MID/FOREFOOT eg for midfoot OA Stress fracture Pain
• Coronal FSPD
• Coronal T1
• Sagittal FSPD tilted to take account of mid/forefoot transverse arch. Should be perpendicular to the line in Fig 5 opposite
• Axial STIR angled along metatarsals and tilted to transverse arch (parallel to lines in Fig 4&5 opposite)
• Sagittal T1
FOREFOOT for Mortons neuroma Plantar plate Sesamoids
A high resolution surface coil improves detail. Alternatively, a wrist coil can be used
8cm FOV 1.4mm slice thickness circa 320 matrix
Minimise toe dorsiflexion
TAKE CARE- Potentially confusing nomenclature here. Forefoot coronal is the short axis - the last image on the right is a coronal image
• Coronal FSPD 512 matrix Perpendicular to proximal phalanx 2nd toe
• Coronal T1 512 matrix (again take care this is short axis)
• Sagittal FSPD angled to 2nd metatarsal shaft
• Axial STIR (CARE This is the long axis) Align as per 4th image on right (angled along metatarsals) and tilt as per the 5th (coronal) image (tilt to transverse arch)
