Unilateral versus bilateral balloon kyphoplasty for osteoporotic vertebral compression fractures.

BACKGROUND Osteoporotic vertebral compression fractures (VCFs) commonly occur in aged people. Balloon kyphoplasty (KP) has been proven to be efficacious for pain relief and reduction of vertebral height for patients with osteoporotic VCFs. However, very little is known about the comparison of clinical and radiographic outcomes between unilateral and bilateral balloon KP in treating this kind of patients. OBJECTIVE To compare the safety and long-term radiographic and clinical outcomes of unilateral or bilateral balloon KP to treat patients with osteoporotic VCFs. STUDY DESIGN A systemic review and meta-analysis of all randomized controlled trials (RCTs) comparing the analgesic efficacy, radiographic outcomes, and complications between unilateral and bilateral balloon KP in patients with osteoporotic VCFs. SETTING The MEDLINE, EMBASE, Pubmed, CINAHL databases, Bandolier, and the Cochrane Controlled Trials Register were systematically searched for evidence from their inception to July 2012 by 2 of the authors (J.L. and L.Z.). METHODS Relevant reports were reviewed by 2 assessors independently and the reference lists of retrieved papers were scrutinized to identify further studies for inclusion, using guidelines set by PRISMA statement criteria. RESULTS Three RCTs were enrolled in this study. The VAS scores showed no statistical difference between the groups before surgery and either at short-term or long-term follow-up. There was no statistical significance in polymethylmethacrylate (PMMA) leakage between the groups. Analysis of 2 studies showed statistical significance in surgery time (WMD -23.77 [-27.83, -19.71]; P < 0.00001) and PMMA (WMD -1.65 [-2.28, -1.02]; P < 0.00001) consumption between the groups. LIMITATIONS There were few data sources from which to extract abstracted data or published studies. There were only 3 RCTs that met criteria enrollment in this meta-analysis. The quality of these trials was quite low (Jadad score: 1-2). Variable reporting of end points and inconsistent definitions meant that we were not able to include every study for each outcome. There was also clinical heterogeneity among the studies. CONCLUSION The efficacy of both unilateral and bilateral balloon KP to provide rapid, significant, and sustained pain relief for patients with osteoporotic VCFs is validated. Unilateral balloon KP is a reasonable treatment for patients with osteoporotic VCFs considering that it could achieve equivalent pain relief with less surgery time and PMMA consumption compared to bilateral balloon KP. There was no evidence to prove that unilateral balloon KP results in higher incidence of PMMA leakage than bilateral balloon KP. Although unilateral balloon KP was less efficacious in the reduction of fractured vertebral body, it is still unclear if the clinical results of balloon KP were positively correlated with the restoration of vertebral height and amount.