Sensitivity and Tests for Evaluation of Plantar Fasciopathy

Plantar fasciopathy (PF), one of the leading causes of foot pain, affects up to one in ten individuals in their lifetime. Characterized by pain and structural alterations at the proximal insertion of the plantar fascia on the calcaneus, the term "PF" has replaced "plantar fasciitis," as degenerative tissue changes predominate over inflammatory processes.

The pathogenesis of PF remains incompletely understood but appears to involve the gastrocnemius muscle, which is part of an integrated biomechanical unit including the calcaneus and the plantar fascia. Diagnosis is primarily based on clinical history and physical examination, while imaging modalities such as ultrasound and magnetic resonance imaging assist in excluding differential diagnoses. A simple clinical test to distinguish PF from other causes of heel pain, such as plantar fat pad syndrome or Baxter's nerve entrapment, could improve diagnostic efficiency.

Given the biomechanical relationship between the Achilles tendon and the plantar fascia, and their shared association with gastrocnemius tightness, a clinical test adapted from Achilles tendon assessment may be useful for diagnosing PF. In 2003, the Royal London Hospital proposed a diagnostic approach for Achilles tendinopathy based on pain reduction during active ankle dorsiflexion, which reduces tension in the tendon. The same concept could be applied, with appropriate modifications, to PF.

The present study aims to evaluate the sensitivity, specificity, reproducibility, and predictive value of localized tenderness at the medial calcaneal tuberosity and of a modified version of the Royal London Hospital Test in patients with PF. Secondarily, it will assess the reproducibility and prevalence of the Silfverskiöld test, supporting the concept of a biomechanical unit involving the triceps surae, calcaneus, and plantar fascia.

Aim of this study is to evaluate the sensitivity, specificity, reproducibility, and predictive value of tenderness at the medial calcaneal tuberosity and of a modified version of the Royal London Hospital Test in patients presenting with clinical signs of PF. The modified version of the Royal London Hospital Test for PF has not yet been formally validated in the literature. However, the study was designed following the methodology adopted by Prof. Maffulli for the validation of the original test. Therefore, this is an exploratory study aimed at collecting preliminary data on this new diagnostic test. The secondary objectives of this study is to evaluate the reproducibility and prevalence of the Silfverskiöld test in the study population.