Utility of Shear Wave Elastography for the Diagnosis of Plantar Fasciitis: Comparison Between Symptomatic and Asymptomatic Sides in Unilaterally Affected Patients

Introduction: Plantar fasciitis (PF) can cause pain in the heel, which can affect everyday activities. While it often resolves on its own, diagnosing PF to rule out other hind foot conditions by imaging modality in cases of recurrence can be difficult. Methods such as MRI and ultrasonography are helpful, but the use of elastography, specifically shear wave elastography (SWE), as a tool for diagnosing PF is being studied. Methodology: This comparative observational study included patients over 18 years presenting with unilateral hind foot pain who were investigated using SWE. Exclusions comprised those who were bilaterally affected and with foot deformities, trauma history, or prior injection therapy. Patients' AOFAS Ankle-Hindfoot Scores were assessed along with visual analog scale (VAS) scores, followed by SWE examination of both heels. Results: The study found no significant difference in the plantar fascia thickness between affected and unaffected sides, with a mean thickness of 4.3±0.8mm and 5.1±0.6mm, respectively. Shear wave velocity (SWV) was lower on the affected side, indicating reduced stiffness compared to the unaffected side. The Spearman rank test revealed strong direct correlations between SWV and both the VAS and HF-AOFAS scores on the affected side. Conclusion: The study observed that SWE enhances B-mode ultrasonography in detecting early PF even with normal plantar fascia thickness, offering a user-independent and reliable tool for treatment monitoring and correlation with functional and pain scores. Further research with larger populations can aid in developing a clinico-radiological classification system for PF, improving prognostication and treatment guidance.