How to increase the accuracy of the diagnosis of the accessory bone of the foot?

Abstract

The study was conducted to search for confident radiological signs in symptomatic cases of accessory bones. A normal accessory bone appearance on X-ray does not exclude that the accessory bone is the source of the discomfort; because of this, MRI examination can later be applied as part of the diagnosis. We retrospectively analysed cases of 64 patients with recognized 70 symptomatic accessory bones of the foot. The average age was 29.2 (range 8-42) years. We included only patients with X-ray and MRI examinations. We investigated the following radiological features of the bone (structural and signal) in relation to soft tissue. The most constant symptoms identified in our study were bone marrow oedema (93%) and soft tissue oedema (77%). Changes in structures in which accessory bones were located or in adjacent structures to accessory bone were identified: tendon changes 51%, fluid adjacent to bone 51% and tenosynovitis 46%. MRI revealed changes in bone structure that are not seen on X-ray, including changes in contour (28%), sclerosis (3%) or osteonecrosis (3%). MRI plays an important role in determining whether accessory bones cause symptoms because it shows specific and accurate changes in accessory bone and/or in adjacent soft tissue.