Background: Kyphoplasty (KP) and vertebroplasty (VP) are minimal invasive procedures for the treatment of painful osteoporotic vertebral compression fractures (VCFs). Evidence for the effectiveness of KP and VP under routine care conditions is low. Predictive factors for a clinically relevant outcome have not been identified yet.

Methods: Aim of the study was to identify predictive factors for the longterm success of both procedures. Additionally safety data (e.g. subsequent, adjacent fractures, cement leakages) were collected. Moreover it should be examined, if the interventions were able to reduce the kyphotic angle and if this reduction was related to clinical outcome parameters. A prospective cohort study was chosen as study design. The expected sample size was not reached. Because of low data quality (sample at the beginning n=88, at the second medical examination n=38 and heterogeneous observation periods) and between groups differences in baseline characteristics we conducted a descriptive analysis.

Results: The groups (KP, VP) differed in baseline characteristics (e.g. spontaneous vs. traumatic fracture, osteoporosis, Oswestry Disability Index). We observed cement leakages in both groups, but none of them required further intervention. Oswestry Disability Index improved by an average of 50 points after KP and by 37 points after VP. Pain was reduced by 67 VAS-points in the KP-group and 61 VAS-points in the VP-group. The pain reduction and the improvement in the ODI-Score was sustained with minimal losses until the end of the observation period after two years.

Discussion: This observational study shows that KP and VP were able to improve functionality and to reduce pain under routine care conditions. Because of between group differences in baseline characteristics direct comparision of outcomes was not feasible. Because of study limitations not all research questions could be fully answered.

Conclusion: Results of currently conducted randomised controlled trials should be followed. Patients should be included in registries and informed about expected benefits and harms prior to both interventions.