Stress fracture of the acromium presenting as a suspected metastasis: A rare consequence of deltoid strengthening program in rotator cuff arthropathy

Acromial fractures constitute 9% of fractures of the scapula, which amounts to 3—5% of shoulder girdle injuries. Stress fractures have been previously described in the body of the scapula, the acromium, the superomedial corner, the lateral border and the coracoid process. We describe a stress fracture of the base of the spine of the scapula in a patient with bony metastatic disease who was investigated for a possible scapula lesion on the basis of an increased uptake in this area on an isotope bone scan. Further imaging demonstrated a stress fracture secondary to the patient performing vigorous deltoid strengthening exercises. The radiological diagnosis was equivocal on an early MRI and isotope bone scan but a CT scan proved diagnostic.