Study design: A retrospective comparative study.
Objective: To compare the characteristics of osteoporotic vertebral fractures (OVFs) with intravertebral fluid (IVF) and those with intravertebral air (IVA), and the efficacy of percutaneous balloon kyphoplasty (PKP) in treating OVFs with these 2 different intravertebral components.
Summary of background data: Previous studies have focused on the efficacy of percutaneous vertebroplasty (PVP) and PKP in treating OVFs with intravertebral cleft. However, no prior studies investigated the impact of the different components of cleft on the therapeutic effect of PVP or PKP.
Methods: On the basis of the presence of IVF or IVA signal on preoperative MR images, 22 patients were classified into IVF group and 13 patients into IVA group. The characteristics of patients with IVF and those with IVA were compared. The anterior and middle heights of the involved vertebrae, the kyphotic angles, the Visual Analogue Scale (VAS), and Oswestry Disability Index (ODI) scores were recorded preoperatively, 1 day after surgery, and at last follow-up.
Results: Severe collapse of involved vertebrae (P=0.024) and the gap appearance of clefts (P=0.004) were significantly more common in IVA group than in IVF group. The vertebral heights, the local kyphotic angles, the VAS, and ODI scores were all significantly improved after PKP in both groups. However, the vertebral height restoration and kyphotic deformity correction were more significant in IVF group than in IVA group (P<0.001). No significant differences regarding VAS and ODI scores were detected between the 2 groups at each follow-up time.
Conclusions: PKP is an effective treatment strategy for both OVFs with IVF and with IVA, whereas vertebral height restoration and kyphotic deformity correction are much more significant in vertebrae with IVF. Presence of IVA without fluid filling-in on MR images may indicate an advanced stage of intravertebral osteonecrosis.