Intravertebral clefts in osteoporotic vertebral compression fractures

Objective. To describe the characteristics, radiographic appearance, and significance of intravertebral clefts in vertebral compression fractures (VCFs) of patients with osteoporosis presenting for vertebroplasty. Methods. This was a prospective radiographic study of 50 consecutive patients with 82 VCFs who underwent vertebroplasty at a tertiary referral center. Patients underwent imaging preoperatively with standing lateral and supine cross-table lateral radiographs and magnetic resonance imaging (MRI). Standing lateral radiographs were also obtained postoperatively. Clefts were defined at the time of vertebroplasty as confluent reservoirs for polymethylmethacrylate (PMMA). Postoperatively, all images were reexamined for the presence and characterization of intravertebral clefts. Results. Twenty-four of 50 patients (48%) had clefted VCFs, and 30 of 82 VCFs (37%) contained clefts. Clefted VCFs were severe, dynamically mobile, and occurred primarily in the thoracolumbar junction. Clefts were detectable by standing lateral radiography in 14%, by supine cross-table radiography in 64%, and by MRI in 96% of fractured vertebrae. Clefts occurred primarily in the anterosuperior portion of the vertebral body, and cleft margins appeared increasingly sclerotic in persistently mobile VCFs. PMMA fill patterns of clefted and unclefted VCFs were distinct. Conclusion. Intravertebral clefts occur frequently in osteoporotic VCFs of patients who present for vertebroplasty. The radiographic characteristics of clefts evolve over time and can be indistinguishable from Kummell's disease in severe, persistently mobile, clefted osteoporotic VCFs.