Age / Sex : 65 / F

Chief complaint: pain on the dorsum of right foot (for 30 years)

What is your impression?

Two weeks later, you can see the final diagonosis with a brief discussion of this case (Please submit only one answer).

Courtesy:  Lee Min Hee, Asan Medical Center, University of Ulsan College of Medicine

Discussion

Answer:  Mueller-Weiss syndrome (Osteonecrosis of navicular bone)

Findings:

Disruption of cygma sign

Decrease in size, esp, flattening of lateral aspect of the navicular bone with sclerosis

Medial/dorsomedial osseous protrusion by the involved navicular

Differential Diagnosis:

Discussion:

Spontaneous adult-onset tarsal navicular osteonecrosis, caused by either compression of navicular bone between the talus and lateral cuneiform or congenital defect

F>M, middle aged adults (40~60 years)

Causes: multifactorial, chronic loading uneven force on suboptimally ossified navicular bone. –a bone is predisposed to central ischemia due to its centripetal vascular perfusion arch.

Imaging findings: Gradual collapse of the navicular bone, fragmentation of lateral aspect of the navicular bone (comma-shaped), leading to lateral subluxation of the talar head, subtalar varus, pseudohindfoot valgus, talocuneiform neoarticulation

Treatment: Initially conservative treatment. Surgical treatment including core decompression & bone graft, arthrodesis 

References:

1. Samim, H. Moukaddam, E Smitamam. Imaging of Mueller-Weiss Syndrome: A review of clinical presentations and imaging spectrum. AJR 2016; 207:W8-W18