Objective: To investigate the efficacy of ultrasound-guided steroid injecti
on for the treatment of proximal plantar fasciitis and to evaluate mechanic
al properties of the heel pad after steroid injection.
Design: Proximal plantar fascia and heel pad were assessed with a 10-MHz li
near array ultrasound transducer. Pain intensity was quantified with a tend
erness threshold (TT) and visual analog scale (VAS). The transducer was inc
orporated into a specially designed device to measure mechanical properties
of the heel pad. Evaluations were performed before injection and at 2 week
s and 3 months after injection.
Setting: An outpatient clinic of a tertiary care center.
Patients: Fourteen consecutive patients with unilateral proximal plantar fa
Intervention: Ultrasound-guided injection of 7 mg betamethasone and 0.5 mL
of 1% lidocaine into the inflamed proximal plantar fascia.
Main Outcome Measures: VAS, TT: heel pad and plantar fascia thickness, and
echogenicity of the proximal plantar fascia on sonogram were assessed. Mech
anical properties included unloaded heel pad thickness, compressibility ind
ex, and energy dissipation ratio.
Results: Both VAS score +/- standard deviation (SD, 5.43 +/- 2.03, 1.39 +/-
2.19, 0.57 +/- 1.40 at the 3 measurements, respectively) and TT +/- SD (5.
05 +/- 1.42, 9.34 +/- 1.84, 9.93 +/- 1.98 kg/cm(2) at the 3 measurements, r
espectively) improved significantly (p < .001) after steroid injection. The
mean thickness of the planter fascia was greater in the symptomatic side t
han in the asymptomatic side before treatment (0.58 +/- 0.13 cm vs 0.40 +/-
0.11 cm. p < .001). The thickness had decreased significantly 3 months aft
er injection (0.46 +/- 0.12 cm at 2 weeks, 0.42 +/- 0.10 cm at 3 months, p
<.001). The hypoechogenicity at the proximal planter fascia disappeared aft
er steroid injection (p < .001). Mechanical properties of the heel pad did
not change 3 months after steroid injection (p > .05),
Conclusion: Ultrasound offers an objective measurement of the therapeutic e
ffect on proximal plantar fasciitis.-Accurate steroid injection under ultra
sound guidance can effectively treat proximal plantar fasciitis without sig
nificant deterioration of the mechanical properties of the heel pads.