Imaging evaluation of progressive collapsing foot deformity

Alfonso E. Maldonado-Morillo, Radiodiagnostic Service, Hospital Universitario Fundacion Jimenez Diaz. Madrid, Spain;
Alex Esnaola-Braceras, Radiodiagnostic Service, Hospital Universitario de Galdakao, Bilbao, Spain;
Danilo E. Salazar-Chiriboga, Radiodiagnostic Service, Hospital Universitario Fundacion Jimenez Diaz. Madrid, Spain;
Gonzalo Moreno-Zamarro, Radiodiagnostic Service, Hospital Universitario Fundacion Jimenez Diaz. Madrid, Spain;
Javier Fernandez-Jara, Radiodiagnostic Service, Hospital Universitario Fundacion Jimenez Diaz. Madrid, Spain;

Progressive collapsing foot deformity (PCFD), previously known as adult-acquired flatfoot deformity, is a complex multifactorial condition characterized by medial arch collapse, hindfoot valgus, and forefoot abduction. Imaging plays a central role in diagnosis, staging, and treatment planning by providing objective assessment of structural and functional abnormalities. Weight-bearing radiography remains the first-line modality for evaluating global alignment and key angular parameters. However, complementary techniques such as ultrasound, computed tomography (CT), weight-bearing CT (WBCT), and magnetic resonance imaging (MRI) are essential for assessing soft tissue integrity, three-dimensional bone relationships, and early pathological changes. Recent advances, including WBCT and artificial intelligence-based tools, have improved diagnostic accuracy and reproducibility. This review provides a comprehensive and practical overview of imaging findings in PCFD, emphasizing the role of each modality, key radiological measurements, and their clinical relevance. The integration of multimodality imaging is essential for accurate diagnosis, classification, and therapeutic decision-making.

Keywords: Progressive collapsing foot deformity. Flatfoot deformity. Saltzman view. Posterior tibial tendon. Spring ligament.