Clinical and scintigraphic evaluation of insufficiency fractures in the elderly

We have undertaken a retrospective review of 1017 Tc-methylene diphosphonate (Tc-MDP) skeletal scintigrams performed in patients over 70 years of age in order to identify those with insufficiency fractures.

Patients with the diagnosis of insufficiency fracture then underwent clinical follow-up of 2 years for mortality, which was compared to the national aged-matched population.

One hundred and ninety-four patients were found to have scintigraphic evidence of fractures categorized as insufficiency fractures. Typical H-shaped sacral fractures were present in only 17 (4%) patients. Multiple sites of fracture were observed in 114 patients; the commonest being in the vertebrae. Radiological corroboration was available in 161 patients (83%) and bone scintigraphic findings were concordant with at least one of plain radiograph, computed tomography or magnetic resonance imaging in 107 (55%) patients. Of the 48 patients with insufficiency fracture who had undergone measurement for bone mineral density (BMD), 38 were found to have osteoporosis/osteopenia. Eighty-six patients died during the follow-up period, which was markedly higher than expected in the age-matched population. There was no definite relationship between the mortality in insufficiency fracture and BMD or the number of fractures.

Our findings demonstrate that insufficiency fractures are common in the elderly and generally occur at multiple sites. The typical H-shaped fractures are rare and their absence should not lead to any mistaken diagnosis. The patients with insufficiency fractures appear to have poor survival but this does not appear to have any significant relationship with either BMD or the number of fractures. Finally, insufficiency fracture is an important diagnosis to make because survival may be improved if specific management is used.