Diagnostic Imaging for Plantar Fasciitis

Imaging Modalities

Weightbearing radiographs have 85% sensitivity and 95% specificity for evaluating thickened plantar fascia and fat pad abnormalities, and should be the initial imaging study for painful heel, according to the American College of Radiology 1, 2
MRI is the most sensitive imaging study for definitive diagnosis, especially in cases that don't respond to initial treatment, with a high degree of accuracy 1
Ultrasound shows good diagnostic accuracy with 80% sensitivity and 88% specificity compared to MRI, and can be used to support diagnosis 1
US elastography demonstrates even higher sensitivity (95%) and specificity (100%) than conventional ultrasound, making it a valuable tool for diagnosis 1

If diagnosis is unclear or symptoms persist beyond 3 months despite treatment, weightbearing radiographs should be obtained to exclude other pathologies, as recommended by Praxis Medical Insights 1
MRI should be considered for definitive evaluation when diagnosis remains uncertain, due to its high sensitivity and specificity 1
Ultrasonography findings that support diagnosis include abnormal focal echogenicity within plantar fascia, edema around plantar fascia, perifascial edema, and increased plantar fascia thickness (>4mm is abnormal) 1

Calcaneal stress fracture should be considered in the differential diagnosis, as it can present with similar symptoms to plantar fasciitis 1
Tarsal tunnel syndrome is another condition that should be considered, as it can cause similar symptoms and can be diagnosed with imaging studies 2
Plantar fascia rupture is a potential complication of plantar fasciitis, and can be diagnosed with imaging studies such as MRI or ultrasound 1