Pathogenesis and diagnosis of delayed vertebral collapse resulting from osteoporotic spinal fracture.

Background Context: In recent years there have been an increasing number of reports on surgical cases involving delayed neurological deficits caused by vertebral collapse after osteoporotic vertebral fracture.

Purpose: We do not yet know which patients are most susceptible to delayed vertebral collapse and subsequent neurological deficits, or whether this pathological condition can be prevented or predicted. In this study, we investigated the mechanism of progression and radiographic features characteristic of this disease, and we report here the predictive or risk factors for delayed osteoporotic vertebral collapse.

Study Design: Retrospectively, we investigated the pathogenesis and diagnosis of delayed vertebral collapse with neurological deficit resulting from osteoporosis.

Patient Sample: A total of 28 patients (7 men and 21 women) with neurological deficits resulting from vertebral collapse caused by osteoporotic vertebral fractures were the subjects for this study.

Outcome Measures: Comparisons and investigations about clinical features and radiographic findings between the patient group of delayed vertebral collapse with neurological deficits and the group of osteoporotic spinal fracture with no neurological deficits.

Methods: The following factors were examined: the cause of injury; the length of time from injury, or the onset of pain, to the onset of neurological symptoms; radiographic findings obtained during the above period; the clinical course of vertebral fracture on plain X-ray films; time of appearance of the intravertebral cleft, and its localization and changes.

Results: Six patients were hospitalized and prescribed a period of 2 weeks of bed rest followed by the fitting of a corset; seven outpatients were corseted but not prescribed bed rest; 15 patients were given medication only at an outpatient clinic. At radiography, intravertebral clefts were detected in 22 patients (79%) during the period from the appearance of pain to the onset of neurological deficit. In 14 patients (50%) who were radiographed every 1 to 2 weeks from the injury to the onset of neurological symptoms, the course of progression to collapse of the vertebral body could be observed.

Conclusion: Initial correct diagnosis and immobilization are important in preventing the delayed collapse with neurological deficit. The presence of an intravertebral cleft and instability of the affected vertebra represent risk factors for vertebral collapse with neurological deficit, requiring careful observation.