‘Haleem's Hen’: A Mnemonic for the Anatomy of Hindfoot Structures at the Level of Sustentaculum Tali on Coronal T1-Weighted Magnetic Resonance Images

Abstract

Category: Hindfoot; Ankle Introduction/Purpose: Magnetic resonance anatomy of the hindfoot as seen at the level of the sustentaculum tali is intricate due to surrounding muscles, tendons, aponeurosis and ligaments. The objective of this work is to provide a mnemonic with illustrative figures to simplify this complex anatomical region on coronal T1-weighted magnetic resonance images (T1-MRIs). Methods: One hundred and twenty-four patients referred for foot and ankle complaints were scanned utilizing standard MRI imaging protocols for evaluation of the hindfoot. Only coronal T1-MRIs of the calcaneus at the level of sustentaculum tali of unremarkably reported patients were selected for the development of this mnemonic. T1- and T2-MRIs of an additional set of patients with hindfoot pathologies were selected to demonstrate how this mnemonic is adapted to identify specific pathologies. Results: Upon viewing the calcaneus with the adjacent anatomical structures on coronal T1-MRIs, the overall appearance resembles a ''Hen in the Nest with Four Eggs.'' The calcaneus represents the body of the hen, while the sustentaculum tali forms the head and neck. The posterior tibial tendon represents the crest of the hen, and the flexor digitorum longus and flexor hallucis longus tendons represent its beak and wattle, respectively. The peroneus brevis and peroneus longus tendons represent the tail, and the long plantar ligament represents the flexed legs of Haleem's hen. The plantar aponeurosis represents the hen's nest. Whereas the abductor hallucis, flexor digitorum brevis, abductor digiti minimi and quadratus plantae muscles are the four eggs. Pes planus, flexor digitorum brevis hemangioma, Baxter's neuropathy associated with chronic denervation abductor digiti minimi atrophy and peroneal tendonitis are some of the hindfoot pathologies that can be identified utilizing the mnemonic. Conclusion: The mnemonic, 'Haleem's Hen in the Nest with Four Eggs,' serves as a simplified phrase for orthopedic surgeons, radiologists and other physicians to easily recall the anatomy of the hindfoot when viewing it at the level of the sustentaculum tali on coronal T1-MRIs. In addition, this mnemonic could be particularly useful when utilized in medical education curriculum for residents, fellows, and medical students. Further research is required to validate this mnemonic as an educational tool in medical training and detail additional hindfoot pathologies that can be identified with it.