An Accessory Peroneocalcaneus Internus Muscle with MRI and US Correlation

An Accessory Peroneocalcaneus Internus Muscle with MRI and US Correlation

Benjamin Matthew Howe, Naveen Srinivasa Murthy

Abstract


The peroneocalcaneus internus (PCI) is a rare accessory muscle of the medial ankle with typical MRI anatomic features allowing differentiation from the more common accessory flexor digitorum longus muscle. To our knowledge, there have been no previously published sonographic images of the peroneocalcaneus internus. A PCI is typically an incidental, asymptomatic finding, but knowledge of the entity may avoid confusion when initially encountered by diagnostic ultrasound. We review the anatomic imaging features which allow for a confident imaging diagnosis and the clinical relevance of this anomaly.

Keywords


PCI; peroneocalcaneus internus; peronaeocalcaneus internus; false flexor hallicus longus; false FHL; accessory muscle



DOI: https://doi.org/10.3941/jrcr.v6i10.1063