Stress fractures of the ankle malleoli diagnosed by ultrasound: a report of 6 cases.

OBJECTIVE

To present the ultrasound appearance of stress fractures (SF) of the ankle malleoli.

MATERIAL AND METHODS

We present a retrospective review of 6 patients (4 women and 2 men, with an age range of 24-52 years, mean age of 39 years) in which ultrasound diagnosed, together with the clinical findings, an SF of the ankle malleoli. For all of these patients ultrasound was the first imaging technique applied because of a clinical suspicion of soft tissue injuries following excessive exertion. Patients were subsequently examined using standard radiographs and/or MRI.

RESULTS

At ultrasound patients showed thickening of the periosteum in all patients, calcified bone callus was evident in 3 out of 6 patients. Cortical irregularities and subcutaneous oedema were found in all but one patient. Colour Doppler showed local hypervascular changes in all patients. Local compression with the transducers during real-time scanning increased pain in all cases.

CONCLUSION

Ultrasound, together with the clinical findings, can diagnose an SF of the ankle malleoli. We suggest that sonologists should include malleolar SF in their differential diagnosis, particularly in the case of perimalleolar pain from over-solicitation. They must also include, as part of every ultrasound examination of the ankle, the evaluation of both malleoli and should be aware of the ultrasound appearance of malleolar SF. If the diagnosis remains uncertain, an MRI should be prescribed.