MRI Monitoring of Tarsal Navicular Stress Fracture Healing. A Case Report.

Abstract

Stress fractures of the tarsal navicular bone are rare injury and assessing its healing is difficult. Tenderness over the tarsal navicular on physical examination is the most reliable sign for assessing fracture healing. However, it is desirable to assess fracture healing with some imaging method. We used serial magnetic resonance imaging (MRI) to assess healing in a patient with a tarsal navicular stress fracture. MRI was useful for the assessment of fracture healing of tarsal navicular stress fracture in our case.

Tarsal Navicular Stress Injury

“…These articles defined (1) NSF as the combination of appropriate foot pain and tenderness, positive delayed bone scan result, and the presence of a fracture line on radiographs or CT images 9 ; and (2) navicular stress reaction (NSR) as similar clinical features, in concert with a positive bone scan result but with no fracture line on plain radiographs or CT images. 9,13 In contemporary practice, MRI is also widely used to diagnose NSF or NSR 1,19 (together labeled navicular stress injury). With respect to the clinical outcome of NSR, we found no published study that focused on describing whether this condition is benign or whether it predisposes a person to the stress fracture condition.…”

Navicular Stress Reactions in Runners

“…It has been recommended that a positive three-phase technetium-99 bone scan followed by a CT scan provides sufficient diagnostic information when injury to the bone has advanced to the point where a fracture line is present. 20,21 Note that MRI does not differentiate edema caused by avascular necrosis from edema related to navicular stress injuries 8 ; furthermore, the thick proximal cortex of the navicular bone at the talonavicular joint can prevent visualization of fracture lines. In cases in which an acute stress reaction injury to the navicular bone is suspected, the use of MRI should not be overlooked 19 ; MRI not only is more specific and sensitive than other imaging modalities but also shows marrow changes in the bone, good anatomical resolution of the fracture pattern, and bony edema on T2-weighted images.…”

Stress fractures in football

“…However, this finding is usually bilateral and the edges are smooth in contrast to the sharp edges of a stress fracture. MRI is useful and using T2-weighed images can assist the diagnosis by showing oedema in acute trauma or in stress injury 84. Other differentials include osteochondritis dissecans (OCD) and avascular necrosis of the navicular 58…”