Study Design. Prospective, parallel-group, controlled, comparative randomized study.
Objective. To compare cement leakage rate and efficacy for vertebral body restoration of balloon kyphoplasty (BK) versus Kiva novel implant with polymethylmethacrylate (PMMA) for treating osteolytic vertebral body metastasis.
Summary of Background Data. Minimally invasively vertebral augmentation techniques with PMMA are mostly performed for treating osteoporotic compression fractures. The Kiva implant with PMMA offers better vertebral body restoration and less PMMA leakage than BK in osteoporotic fractures. No previous study compared leakage rate and efficacy for vertebral body restoration in traditional BK and Kiva with PMMA in osteolytic vertebral body metastases.
Methods. This study examined 23 patients (71 ± 13 yr) with 41 osteolytic vertebral bodies, who received Kiva with low viscosity PMMA and 24 patients (70 ± 11 yr) with 43 vertebral body osteolyses, who were reinforced with BK and high viscosity PMMA. All osteolyses were graded as Tomita 1 to 3. Anterior vertebral body height ratio (AVBHr), posterior vertebral body height ratio (PVBHr), and middle vertebral body height ratio (MVBHr), Gardner kyphotic deformity, PMMA leakage and were measured and compared between the groups. Visual analogue scale and Oswestry Disability Index were used for functional outcome evaluation.
Results. No patient survived after 3 months. Asymptomatic PMMA leakage occurred in 4 (9.3%) vertebrae in the BK group solely (2 to the spinal canal, in Tomita grade 3 osteolysis) Anterior, posterior and middle vertebral body height ratio, Gardner angle improved insignificantly in both groups. Visual anlogue scale and Oswestry Disability Index improved postoperatively similarly in both groups (P < 0.001).
Conclusion. BK and Kiva provided equally significant spinal pain relief in patients with cancer with osteolytic metastasis. The absence of cement leakage in the Kiva group and absence of neurological complication in the BK group leakages reflects the safety of both augmentation techniques even in significant osteolysis. The lack of cement leakage in the Kiva cases, although low viscosity PMMA was used, increases this implant safety in augmenting severely destructed thoracolumbar vertebrae and sacrum from osteolytic metastasis.
Level of Evidence: 1
Percutaneous Kiva implant with polymethylmethacrylate (PMMA) and balloon kyphoplasty (BK) similarly, although insignificantly, restored postoperatively sagittal vertebral body height in patients with metastatic osteolysis Tomita grades 1 to 3 and prognostic Tomita scores 6 to 8. The main advantages of Kiva in this series was the absence of PMMA cement leakage even in significant osteolyses, compared with the 10% leakage rate observed in the BK cases and the better restoration of middle vertebral height.
From the Department of Orthopaedic Surgery, General Hospital “Agios Andreas,” Patras, Greece.
Address correspondence and reprint requests to Panagiotis Korovessis, MD, PhD, Department of Orthopaedic Surgery, General Hospital of Patras, GR-26224 Patras, Greece; E-mail: firstname.lastname@example.org
Acknowledgment date: June 20, 2013. First revision date: September 4, 2013. Second revision date: October 16, 2013. Acceptance date: October 25, 2013.
The manuscript submitted does not contain information about medical device(s)/drug(s).
No funds were received in support of this work.
No relevant financial activities outside the submitted work.