MRI evaluation of interconnections between flexor hallucis longus and flexor digitorum longus around the Master knot of Henry.

• Normal anatomical variations around the Master knot of Henry were not extensively studied in the radiology literature before. • MRI identified the various types, sizes, and locations of interconnections between the flexor digitorum longus tendon and the flexor hallucis longus tendon. • MRI is a useful noninvasive tool for evaluating the interconnections between the flexor digitorum longus tendon and the flexor hallucis longus tendon.