The Clinical Diagnosis and Treatment of an Anterior Calcaneal Process Fracture Overlooked on Imaging: A Case Study

BACKGROUND: Anterior calcaneal process fractures are often overlooked on radiographs. Given a similar clinical presentation, these fractures are frequently misdiagnosed as lateral ankle sprains. CASE DESCRIPTION: A 43-year-old male was referred to physical therapy following an inversion ankle injury. Sites of interest identified on initial radiography were asymptomatic, including an os trigonum and possible dorsal talar avulsion fracture. Screening with the Ottawa ankle rules was negative. His clinical presentation was similar to an inversion ankle sprain with concordant swelling and pain. OUTCOME: Subsequent ankle imaging was completed following a lack of expected clinical progression, revealing a subtle calcaneal fracture overlooked on initial imaging. The patient was referred to orthopedics and managed in a boot with partial weight-bearing. He was released to full weight-bearing 6 weeks later with resolution of pain and gradual recovery of normalized range of motion and strength. DISCUSSION: Improving proficiency of interpreting radiograph images as physical therapists, application of the four-eyes principle when reading images, and awareness of potential fractures with negative Ottawa ankle rules screening are beneficial to early and accurate diagnosis and treatment of foot fractures. JOSPT Cases 2025;5(1):12-17. Epub 20 December 2024. doi:10.2519/josptcases.2024.0086