Cubonavicular coalition

A 40-year old woman, known with bilateral pedes planovalgi presented to the hospital, with mechanical pain of some time duration. There was no history of trauma. Clinical examination revealed a decreased range of motion of the right subtalar joint. An X-ray of the foot showed blurring of the cubonavicular joint, with focal degenerative changes (Fig. A, black arrow). A sonography was performed, showing signs of synovitis of the intertarsal and subtarsal joints. On MRI, a narrowed and hazy cubonavicular joint was seen on sagittal STIR (Fig. B) and T1 (Fig. C), and on axial STIR (Fig. D) and T1 (Fig. E) with subchondral cyst formation and bone marrow edema (white arrows). Diagnosis of cubonavicular coalition was made. Conservative treatment was suggested. In case of worsening of symptoms surgical resection is an option.