Tendons in the plantar aspect of the foot: MR imaging and anatomic correlation in cadavers.

OBJECTIVE: The purpose of this anatomic imaging study was to illustrate the normal complex anatomy of tendons of the plantar aspect of the ankle and foot using magnetic resonance (MR) imaging with anatomic correlation in cadavers.

DESIGN: Seven fresh cadaveric feet (obtained and used according to institutional guidelines, with informed consent from relatives of the deceased) were studied with intermediate-weighted fast-spin-echo MR imaging. For anatomic analysis, cadaveric specimens were sectioned in 3-mm-thick slices in the coronal and axial planes that approximated the sections acquired at MR imaging.

RESULTS: The entire courses of the tendons into the plantar aspect of the foot were analyzed. The tibialis posterior tendon has a complex distal insertion. The insertions in the navicular, second, and third cuneiforms bones were identify in all cases using axial and coronal planes. A tendinous connection between the flexor hallucis longus and the flexor digitorum longus tendons was identified in five of our specimens (71%). The coronal plane provided the best evaluation. The peroneus longus tendon changes its direction at three points then obliquely crosses the sole and inserts in the base of the first metatarsal bone and the plantar aspect of the first cuneiform.

CONCLUSIONS: MR imaging provides detailed information about the anatomy of tendons in the plantar aspect of the ankle and foot. It allows analysis of their insertions and the intertendinous connection between the flexor hallucis longus and the flexor digitorum longus tendons.