***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
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    Input: The  height gain of vertebral bodies after vertebroplasty  and geometrical stability was evaluated over a one-year period . Osteoporotic fractures were treated with vertebroplasty . The vertebral geometry and disc spaces were analysed using reformatted computed tomography ( CT ) images : heights of the anterior , posterior , and lateral vertebral walls , disc spaces , endplate angles , and minimal endplate distances . Vertebrae were assigned to group I [ severe compression ( anterior height/posterior height ) < 0.75 ] and group II ( moderate compression index > 0.75 ) . A total of 102 vertebral bodies in 40 patients ( 12 men , 28 women , age 70.3 ± 9.5 ) were treated with vertebroplasty  and prospect ively followed for 12 months . Group I showed a greater benefit compared with group II with respect to anterior height gain ( + 2.1 ± 1.9 vs + 0.7 ± 1.6 mm , P < 0.001 ) , reduction of endplate angle ( −3.6 ± 4.2 vs −0.8 ± 2.3 ° , P < 0.001 ) , and compression index ( + 0.09 ± 0.11 vs + 0.01 ± 0.06 , P < 0.001 ) . At one-year follow-up , group I demonstrated preserved anterior height gain ( + 1.5 ± 2.8 mm , P < 0.015 ) and improved endplate angle ( −3.4 ± 4.9 ° , P < 0.001 ) . In group II , the vertebral heights returned to and were fixed at the pre-interventional levels . Vertebroplasty  provided vertebral height gain over one year , particularly in cases with severe compression . Vertebrae with moderate compression were fixed and stabilized at the pre-treatment level over one year BACKGROUND Previous studies have shown that alendronate can increase bone mineral density ( BMD ) and prevent radiographically defined ( morphometric ) vertebral fractures . The Fracture Intervention Trial aim ed to investigate the effect of alendronate on the risk of morphometric as well as clinical ly evident fractures in postmenopausal women with low bone mass . METHODS Women aged 55 - 81 with low femoral-neck BMD were enrolled in two study groups based on presence or absence of an existing vertebral fracture . Results for women with at least one vertebral fracture at baseline are reported here . 2027 women were r and omly assigned placebo ( 1005 ) or alendronate ( 1022 ) and followed up for 36 months . The dose of alendronate ( initially 5 mg daily ) was increased ( to 10 mg daily ) at 24 months , with maintenance of the double blind . Lateral spine radiography was done at baseline and at 24 and 36 months . New vertebral fractures , the primary endpoint , were defined by morphometry as a decrease of 20 % ( and at least 4 mm ) in at least one vertebral height between the baseline and latest follow-up radiograph . Non-spine clinical fractures were confirmed by radiographic reports . New symptomatic vertebral fractures were based on self-report and confirmed by radiography . FINDINGS Follow-up radiographs were obtained for 1946 women ( 98 % of surviving participants ) . 78 ( 8.0 % ) of women in the alendronate group had one or more new morphometric vertebral fractures compared with 145 ( 15.0 % ) in the placebo group ( relative risk 0.53 [ 95 % Cl 0.41 - 0.68 ] ) . For clinical ly apparent vertebral fractures , the corresponding numbers were 23 ( 2.3 % ) alendronate and 50 ( 5.0 % ) placebo ( relative hazard 0.45 [ 0.27 - 0.72 ] ) . The risk of any clinical fracture , the main secondary endpoint , was lower in the alendronate than in the placebo group ( 139 [ 13.6 % ] vs 183 [ 18.2 % ] ; relative hazard 0.72 [ 0.58 - 0.90 ] ) . The relative hazards for hip fracture and wrist fracture for alendronate versus placebo were 0.49 ( 0.23 - 0.99 ) and 0.52 ( 0.31 - 0.87 ) . There was no significant difference between the groups in numbers of adverse experiences , including upper-gastrointestinal disorders . INTERPRETATION We conclude that among women with low bone mass and existing vertebral  fractures , alendronate is well tolerated and substantially reduces the frequency of morphometric and clinical vertebral fractures , as well as other clinical fractures Previously , we reported significantly reduced pain and improved mobility persisting for 6 months after kyphoplasty of chronically painful osteoporotic vertebral fractures in the first prospect i ve controlled trial . Since improvement of spinal biomechanics by restoration of vertebral morphology may affect the incidence of fracture , long-term clinical benefit and thereby cost-effectiveness , here we extend our previous work to assess occurrence of new vertebral fractures and clinical parameters 1 year after kyphoplasty compared with a conservatively treated control group . Sixty patients with osteoporotic vertebral fractures due to primary osteoporosis were included : 40 patients were treated with kyphoplasty , 20 served as controls . All patients received st and ard medical treatment .  Morphological characteristics , new vertebral fractures , pain ( visual analog scale ) , physical function [ European Vertebral Osteoporosis Study ( EVOS ) score ] ( range 0–100 each ) and back-pain-related doctors ’ visits were re-assessed 12 months after kyphoplasty . There were significantly fewer patients with new vertebral fractures of the thoracic and lumbar spine , after 12-months , in the kyphoplasty group than in the control group ( P=0.0084 ) . Pain scores improved from 26.2 to 44.4 in the kyphoplasty group and changed from 33.6 to 34.3 in the control group ( P=0.008 ) . Kyphoplasty treated patients required a mean of 5.3 back-pain-related doctors ’ visits per patient compared with 11.6 in the control group during 12 months follow-up ( P=0.006 ) . Kyphoplasty as an addition to medical treatment and when performed in appropriately selected patients by an interdisciplinary team persistently improves pain and reduces occurrence of new vertebral fractures and healthcare utilization for at least 12 months in individuals with primary osteoporosis Vertebroplasty and kyphoplasty are associated with a recurrent fracture rate of 2.4 % to 23 % , which is lower than the general natural history of untreated osteoporotic fractures . Some authors suggest the risk of refracture at adjacent vertebra will be reduced by prophylactic stabilization . We therefore compared the refracture rate after prophylactic balloon kyphoplasty in 60 patients r and omized into groups with either monosegmental balloon kyphoplasty or adjacent prophylactic balloon kyphoplasty .  The level ( superior versus inferior ) for prophylactic stabilization was chosen according to fracture type . We evaluated patients for 12 months using radiographs , visual analog scale scores , and SF-36 scores . We followed 23 of 30 patients in the monosegmental group and 27 of 30 patients in the prophylactic group . We observed no difference in the 1-year refracture rates between the two groups ( five patients in the monosegmental group and seven in the prophylactic group ) . Leakage into the disc was the presumed cause of adjacent fractures in 50 % of the patients . Disc leakage and refracture rate did not correlate as a result of the low patient number . Based on our data , we believe there is no indication for prophylactic stabilization of adjacent segments with balloon kyphoplasty . Level of Evidence : Level II , therapeutic study . See the Guidelines for Authors for a complete description of levels of evidence BACKGROUND Balloon kyphoplasty is a minimally invasive procedure for the treatment of painful vertebral fractures , which is intended to reduce pain and improve quality of life . We assessed the efficacy and safety of the procedure . METHODS Adults with one to three acute vertebral fractures were eligible for enrolment in this r and omised controlled trial at 21 sites in eight countries . We r and omly assigned 300 patients by a computer-generated sequence to receive kyphoplasty treatment ( n=149 ) or non-surgical care ( n=151 ) . The primary outcome was the difference in change from baseline to 1 month in the short-form (SF)-36 physical component summary ( PCS ) score ( scale 0 - 100 ) between the kyphoplasty and control groups . Quality of life and other efficacy measurements and safety were assessed up to 12 months . Analysis was by intention to treat . This trial is registered with Clinical Trials.gov , number NCT00211211 . FINDINGS 138 participants in the kyphoplasty group and 128 controls completed follow-up at 1 month . By use of repeated measures mixed effects modelling , all 300 r and omised participants were included in the analysis . Mean SF-36 PCS score improved by 7.2 points ( 95 % CI 5.7 - 8.8 ) , from 26.0 at baseline to 33.4 at 1 month , in the kyphoplasty group , and by 2.0 points ( 0.4 - 3.6 ) , from 25.5 to 27.4 , in the non-surgical group ( difference between groups 5.2 points , 2.9 - 7.4 ; p<0.0001 ) . The frequency of adverse events did not differ between groups . There were two serious adverse events related to kyphoplasty ( haematoma and urinary tract infection ) ; other serious adverse events ( such as myocardial infa rct ion and pulmonary embolism ) did not occur perioperatively and were not related to procedure . INTERPRETATION Our findings suggest that balloon kyphoplasty is an effective and safe procedure for patients with acute vertebral fractures and will help to inform decisions regarding its use as an early treatment option BACKGROUND Percutaneous vertebroplasty is increasingly used for treatment of pain in patients with osteoporotic vertebral compression fractures , but the efficacy , cost-effectiveness , and safety of the procedure remain uncertain . We aim ed to clarify whether vertebroplasty has additional value compared with optimum pain treatment in patients with acute vertebral fractures . METHODS Patients were recruited to this open-label prospect i ve r and omised trial from the radiology departments of six hospitals in the Netherl and s and Belgium . Patients were aged 50 years or older , had vertebral compression fractures on spine radiograph ( minimum 15 % height loss ; level of fracture at Th5 or lower ; bone oedema on MRI ) , with back pain for 6 weeks or less , and a visual analogue scale ( VAS ) score of 5 or more . Patients were r and omly allocated to percutaneous vertebroplasty or conservative treatment by computer-generated r and omisation codes with a block size of six . Masking was not possible for participants , physicians , and outcome assessors . The primary outcome was pain relief at 1 month and 1 year as measured by VAS score . Analysis was by intention to treat . This study is registered at Clinical Trials.gov , number NCT00232466 . FINDINGS Between Oct 1 , 2005 , and June 30 , 2008 , we identified 431 patients who were eligible for r and omisation . 229 ( 53 % ) patients had spontaneous pain relief during assessment , and 202 patients with persistent pain were r and omly allocated to treatment ( 101 vertebroplasty , 101 conservative treatment ) . Vertebroplasty result ed in greater pain relief than did conservative treatment ; difference in mean VAS score between baseline and 1 month was -5·2 ( 95 % CI -5·88 to -4·72 ) after vertebroplasty and -2·7 ( -3·22 to -1·98 ) after conservative treatment , and between baseline and 1 year was -5·7 ( -6·22 to -4·98 ) after vertebroplasty and -3·7 ( -4·35 to -3·05 ) after conservative treatment . The difference between groups in reduction of mean VAS score from baseline was 2·6 ( 95 % CI 1·74 - 3·37 , p<0·0001 ) at 1 month and 2·0 ( 1·13 - 2·80 , p<0·0001 ) at 1 year . No serious complications or adverse events were reported . INTERPRETATION In a subgroup of patients with acute osteoporotic vertebral compression fractures and persistent pain , percutaneous vertebroplasty  is effective and safe . Pain relief after vertebroplasty is immediate , is sustained for at least a year , and is significantly greater than that achieved with conservative treatment , at an acceptable cost . FUNDING ZonMw ; COOK Medical PURPOSE Kyphoplasty and vertebroplasty offer two minimally invasive operative stabilization procedures for vertebral compression fractures . The purpose of this prospect i ve study was to investigate whether both procedures are able to reduce pain and to preserve postoperative vertebral height during a 1-year follow up . 
    Output:
    
The combined odds ratio of vertebroplasty and kyphoplasty versus conservative treatment  , namely 0.96 , gave a hint that there might be little difference .