Liu 2010

Methods	Design: single‐centre, two‐arm, randomised controlled trial Setting: Taichung, Taiwan Timing: not stated Interventions: percutaneous vertebroplasty versus kyphoplasty Sample size:a priori sample size calculation not reported Analysis: not reported
Participants	Number of participants Number screened not reported 100 participants randomised (50 in each group) Loss to follow‐up not explicitly reported Data may have been available for all participants at the final 6‐month follow‐up Inclusion criteria Confirmed osteoporotic vertebral compression fracture at the thoraco‐lumbar junction (T12‐L1) Exclusion criteria None reported Baseline characteristics Vertebroplasty Group Mean (SD) age: 74.3 (6.4) years; 38 female, 12 male Mean (SD) duration between 'injury' and treatment: 15.8 (6.7) days Location: 12 T12, 38 L1 Mean (SD) pain at baseline: 7.9 (0.7) Kyphoplasty group Mean (SD) age: 72.3 (7.6) years; 39 female, 11 male Mean (SD) duration between 'injury' and treatment: 17.0 (7.7) days Location: 11 T12, 39 L1 Mean (SD) pain at baseline: 8.0 (0.8)
Interventions	Percutaneous vertebroplasty The surgical procedures involved IV general anaesthesia (Propofol) and 2% xylocaine injected locally. A special bone biopsy needle (Angiotech, USA) was passed percutaneously and slowly through each side of the pedicle into the vertebral body. The bone filler PMMA (Zimmer) was prepared and mixed with both gentamicin, to reduce risk of infection, and powder containing barium, allowing X‐ray visualisation. An optimal amount of bone filler was injected into the vertebral body via the needles on both sides. All procedures were performed under a mobile C‐arm X‐ray. Balloon kyphoplasty The same anaesthesia was employed. Using image guidance, two small incisions were made, a probe was placed into the vertebral space at the fracture site. The bone was drilled and a balloon (VCF‐X CentralMedical Tech., Taiwan), called a bone tamp, was inserted on each side. The balloons were then inflated with contrast medium (to facilitate image guidance X‐rays) and expanded to the desired height and removed. The spaces created by the balloons were then filled with PMMA (prepared as for vertebroplasty) to bind the fracture. Follow‐up All participants undertook an orally administered treatment regimen to protect their bone density after surgery (details not reported).
Outcomes	Outcomes were reported at baseline, 3 days, 6 months, 1, 2 and 5 years. Primary outcomes Measurement of vertebral body height Measurement of kyphotic wedge angle (to evaluate kyphosis) Pain, measured on a 10‐point VAS Outcomes included in this review Mean pain
Source of funding	Grant from Chung‐Shan Medical University Hospital (CS08110).
Notes	Trial registration: not found. We extracted outcomes at 6 months, 1 and 2 years.
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Randomly assigned according to permuted block randomisation which was likely to be adequate.
Allocation concealment (selection bias)	Unclear risk	Whether or not treatment allocation was concealed is not reported.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	Whether or not participants and investigators were blinded to treatment allocation is not reported.
Blinding of outcome assessment (detection bias) Self‐reported outcomes (e.g., pain, disability)	Unclear risk	Whether or not participants were blinded to treatment allocation is not reported.
Blinding of outcome assessment (detection bias) Objective outcomes (e.g., radiographic outcomes)	Unclear risk	Quote: "Radiographic measurement was made by technicians 'blind' to treatment group status, with variability controlled via inter‐ and intra‐observer comparisons". No details of the inter‐ and intra‐observer comparisons are reported.
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Completeness of follow‐up was not explicitly reported.
Selective reporting (reporting bias)	Unclear risk	Trial not registered and trial protocol was not published. All outcomes listed in the methods are reported.
Other bias	Low risk	None apparent.