Cement Distribution Patterns in Osteoporotic Vertebral Compression Fractures with Intravertebral Cleft: Effect on Therapeutic Efficacy.

Objective: To determine cement distribution patterns on therapeutic efficacy after percutaneous vertebroplasty treatment of osteoporotic vertebral compression fractures (OVCFs) with intravertebral cleft (IVC).

Methods: Patients who were treated with percutaneous vertebroplasty for single OVCFs with IVC and met this study's inclusion criteria were retrospectively reviewed. The follow-up period was at least 2 years. Distribution patterns of cement in the IVC area were respectively specified into 2 groups: group 1: solid lump distribution pattern (n = 22); group 2: the comparatively diffused pattern (n = 90). Radiologic and clinical parameters were analyzed and compared. Then, associations of recollapse with covariates and a risk score were further analyzed and developed to predict recollapse of the augmented vertebrae.

Results: At the immediate postoperative period, all patients benefited from significant improvement in vertebrae height and kyphotic angle correction. However, significant recollapse was observed at the 2 years postoperative follow-up for the patients in group 1. Furthermore, we found that preoperative severe kyphotic deformity (a cutoff value of 12.5°), solid lump cement distribution pattern, and larger reduction angle (a cutoff value of 8.3°) was significantly associated with increased risk for recollapse. A risk score was developed based on the number of risk factors present in each patient and the receiver operating characteristic curve of the risk score generated an area under the curve of 0.788 (95% confidence interval 0.702-0.873, P = 0.000).

Conclusions: The comparatively diffused pattern shows better long-term radiologic and clinical outcomes for the treatment for OVCFs with IVC. A risk score can be used to predict the incidence of recollapse.