Diagnostic accuracy of clinical, radiological and device-driven tests for the detection of First Ray Instability: A systematic review.

Introduction: First Ray Instability (FRI) and especially hypermobility leads to the collapse of the medial longitudinal arch's structural framework, which reduces the foot's ability to become a rigid lever for propulsion, resulting in progressive foot deformities. Early detection of FRI with prompt intervention helps prevent degenerative foot deformities. Various manual, device-based and radiographic diagnostic tests for FRI quantification have been described in the literature.