Clinical utility of sonography in diagnosing plantar fasciitis

The purpose of this study was to investigate the efficacy of sonography in the detection of plantar fasciitis (PF) compared with magnetic resonance imaging (MRI) findings in subjects with inferior heel pain.

Seventy-seven patients with unilateral (n = 9) and bilateral (n = 68) heel pain were studied. Seventy-seven age- and sex-matched asymptomatic subjects served as a control group. Magnetic resonance imaging was used to establish a diagnosis of PF with sagittal T1-weighted, T2-weighted, and short tau inversion recovery sequences. The sonographic appearances of PF were compared with MRI findings. Plantar fascia and heel pad thickness were also measured on both imaging modalities.

Compared with MRI, sonography showed 80% sensitivity and 88.5% specificity in assessing PF. A strong correlation was found between plantar fascia and fat pad thickness measurements done by sonography (P < .001; r = 0.854) and MRI (P < .001; r = 0.798). Compared with the asymptomatic volunteers, patients with PF had significant increases in plantar fascia and heel pad thicknesses, weight, and body mass index (P = .0001). Heel pad thickness was also significantly increased with pain duration (P = .021).

Although MRI is the modality of choice in the morphologic assessment of different plantar fascia lesions, sonography can also serve as an effective tool and may substitute MRI in the diagnosis of PF.