Calcium-phosphate and polymethylmethacrylate cement in long-term outcome after kyphoplasty of painful osteoporotic vertebral fractures

Study Design. A comparative prospective trial evaluating 3- year outcome. Objective. To compare clinical and morphologic outcomes as well as follow- up fractures after kyphoplasty of painful osteoporotic vertebral fractures with calcium-phosphate ( CaP) cement ( group 1) and with polymethylmethacrylate ( PMMA)- cement ( group 2). Summary of Background Data. CaP cements seem to be an alternative material for usage in kyphoplasty of vertebral fractures. CaP cements are biodegradable and replaceable by newly formed bone after implantation. Concerns have been raised with regard to the stability of resorbable CaP- cements after implantation into vertebrae post kyphoplasty. Calcibon is a possible CaP cement, which exhibited adequate stability in short- term observations. Materials and Methods. Kyphoplasty was performed in 40 consecutive patients with primary osteoporosis and painful vertebral fractures, 20 received CaP- cement, 20 were treated with PMMA- cement. All patients received a pharmacological antiosteoporosis treatment ( 1000 mg calcium, 1000 IU vitamin D3, and oral aminobisphosphonate), pain medication, and physiotherapy. Pain ( visual analog scale [ VAS]; range, 0 - 100), mobility ( EVOS- score; range, 0 - 100) and radiomorphologic measurements were assessed at baseline and after 6, 12, and 36 months. Results. There were no statistically significant differences between the CaP and PMMA- cement group regarding VAS- scores, EVOS- scores, or height- restoration at any time point. Furthermore, there was no significant difference in the occurrence of vertebral follow- up fractures between both groups during the 3- year follow- up period. Conclusion. CaP cement, e. g., Calcibon, is as effective and safe as conventional PMMA- cement with regard to immediate and sustained pain reduction and improvement of mobility after kyphoplasty of patients with painful osteoporotic vertebral fractures. CaP cement has the potential of being resorbed and replaced by newly formed bone tissue; thus, it seems to be a promising alternative for PMMA also in younger patients with painful vertebral fractures.