Background: Vertebral compression fractures are common among the elderly, which is conditioned
by osteoporosis. They cause back pain and limit the patient’s activities. The Kiva® VCF Treatment
System is a new device to treat vertebral compression fractures. Compared to other methods, the
utilization of the Kiva System reduces the risk for complications and delivers improvements in back
pain reduction and functionality.
Objectives: Evaluation of safety and effectiveness of the Kiva System in comparison to balloon
kyphoplasty on the basis of matched pairs.
Methods: 52 patients (47 - 89 years, 68 fractures) were treated with balloon kyphoplasty or with
the new Kiva System. Back pain and impairment of motility were assessed preoperatively and 6
months postoperatively, with the Visual Analog Scale (VAS) and Oswestry Disability Index (ODI). The
operation time and cement extravasation were recorded. Control radiographs were evaluated for
new fractures and vertebral heights.
Results: Mean VAS values in both groups improved from preoperatively 87.6 ± 12.8 and 83.1 ± 14.9
to 10.8 ± 20.8 and 24.6 ± 11.0 6 months after the treatment. The improvement after 6 months in the
Kiva group was significantly better than in the balloon kyphoplasty group (P < 0.0001). Mean ODI scores
in both groups also improved from 68.7% ± 15.8% in the Kiva group and 80.6% ± 8.6% in the balloon
kyphoplasty group preoperatively to 24.8 ± 18.6% and 33.2 ± 6.3% 6 months after treatment. The mean
operation time for the Kiva group was 12.7 ± 3.7 minutes per vertebra and cement leakage occurred in 6
patients. The mean operation time for the balloon kyphoplasty group was 34.1 ± 7.0 minutes per vertebra
and cement leakage occurred in 8 patients. Anterior and mid vertebral height in the Kiva group increased
from preoperatively 21.06 ± 7.44 mm and 18.36 ± 5.64 mm to postoperatively 22.41 ± 7.14 mm and
20.41 ± 6.00 mm. Anterior and mid vertebral height in the balloon kyphoplasty group increased from
preoperatively 21.68 ± 2.06 mm and 21.97 ± 1.78 mm to postoperatively 25.09 ± 2.54 mm and 25.29 ±
2.10 mm. Vertebral height restoration could be therefore maintained with both procedures for 6 months.
In the Kiva group 2 cases of nonadjacent fractures and one case of adjacent fractures were observed.
In the balloon kyphoplasty group 9 cases of adjacent, as well as 5 cases of nonadjacent, fractures were
observed. In the Kiva group significant fewer fractures occurred.
Limitations: The study includes only 26 patients for each procedure, which were compared on the
basis of matched pairs.
Conclusion: The Kiva System appears to be a safe and effective procedure for the treatment of
vertebral compression fractures. Six months after treatment with the Kiva System, better VAS values
than the values after the treatment with balloon kyphoplasty were recorded. Reduction in functional
impairment was as successful as it was after balloon kyphoplasty. Vertebral height restoration was
observed in both groups, which was sustained for 6 months. The risk of cement extravasation
during the Kiva Treatment is nearly the same as in balloon kyphoplasty; however, it requires a shorter
operation time and produces fewer new fractures.
Key words: Vertebral compression fracture, Kiva, kyphoplasty, vertebral augmentation,
osteoporosis, back pain