Initial clinical experience with a novel vertebral augmentation system for treatment of symptomatic vertebral compression fractures: a case series of 26 consecutive patients

Abstract

Background: Minimally invasive vertebral augmentation procedures are widely used to treat vertebral compression fractures although procedural polymethylmethacrylate cement leakage remains common. We report herein our initial experience with a novel vertebral augmentation technique designed to treat symptomatic vertebral osteoporotic fractures and osteolytic metastases with minimal cement extravasation.

Methods: Forty-two vertebral fractures were identified in 26 consecutive patients (mean age 74 ± 9 years). All patients were treated with a novel percutaneous vertebral augmentation device (Kiva VCF Treatment System, Benvenue Medical, Santa Clara, CA, USA). Indications for surgery included recent (≤ 3 months) symptomatic osteoporotic vertebral fracture (n = 34) and pathologic vertebral fractures (e.g. metabolic bone disease, myeloma, metastasis) (n = 8) located between T10 and S1. Patient outcomes were evaluated pre-treatment and at 2- and 6-month follow-up visits. Postoperative cement extravasation was assessed with computed tomography. Patient-reported back pain was quantified using an 11-point numeric scale. Back-specific functional disability was self-reported with the Oswestry Disability Index on a 0 to 100% scale.

Results: No cases of intraoperative hypotension, respiratory disturbance, neurological deterioration, infection, or death were observed. There were 2 (4.8%) levels where anterior cement leakage was visible radiographically in patients with osteolyses. No intracanal leakage was observed. Back pain scores improved 71% (p < 0.001) from pre-treatment to the 6-month follow-up. Back function improved 56% from baseline to 6 months (p < 0.001).

Conclusions: The initial clinical experience with the Kiva System demonstrated significant improvements in back pain and function with minimal and clinically insignificant procedural cement leakage.

Figures

Figure 1

Intraoperative fluoroscopic images of the Kiva® VCF Treatment System consisting of a percutaneously introduced nitinol coil guidewire advanced through a deployment cannula (a) and then fully coiled within the cancellous portion of the fractured vertebral body (b). A radiopaque PEEK Implant is delivered incrementally over the removable guidewire (c) in a continuous loop to form a nesting, cylindrical column providing vertical displacement that results in endplate re-elevation and fracture reduction (d).

Figure 2

Preoperative lateral radiograph showing osteoporotic vertebral compression fractures at L2 and L4 in a 72-year-old female (a). Post-operative radiograph 6 months after treatment with the Kiva® VCF Treatment System demonstrating excellent vertebral fracture reduction (b). Corresponding axial computed tomography scan at 6 months illustrating excellent cement containment within the implant at L2 (c).

Figure 3

Improvement in back pain and function through 6 months following vertebral augmentation. Values are mean ± 95% confidence intervals. ODI: Oswestry Disability Index.