Risk factor analysis for recollapse of cemented vertebrae after percutaneous augmentation

English Keywords:Vertebral augmentation  Osteoporotic vertebral compression fracture  Recollapse

English Abstract:

  【Abstract】 Objectives: To analyze the risk factors for recollapse of cemented vertebrae after percutaneous augmentation in patients with osteoporotic vertebral compression fractures(OVCFs). Methods: From January 2012 to June 2014, 304 cases of single segmental OVCFs were retrospectively reviewed. The following covariates: age, gender, body mass index(BMI), bone mineral density(BMD), thoracolumbar fracture, preoperative osteonecrosis were recorded. The surgical variables were as follows: operation approach, injected cement volume, cement distribution pattern(solid lump pattern or interdigitation pattern), cement filling around fracture line area. Cobb angles of treated vertebrae at 3d post-operation and the final follow-up, and recollapsed vertebrae numbers were assessed. Furtherly, an one-way analysis of variance with those parameters and binary logistic regression analysis was made to determine the relative risk factors. Results: 3304 patients had operation successfully. The average operation time was 41.0±3.5 minutes(range, 35 minutes to 50 minutes). 240 patients were evaluated with a mean of 2.6±1.1 years follow-up(range, 1-4 year). 30 cemented vertebrae were identified with recollapse(12.5%), 23 of them occurred in thoracolumbar area. According to one-way analysis, low BMD, small amount of cement injected, preoperative osteonecrosis, solid lump cement pattern, and insufficient cement distributing around fracture line area were analyzed as potential risk factors(P<0.05), while the differences of gender, age, BMI, operation approach impacted the recollapse without significance(P>0.05). Furthemore, preoperative osteonecrosis existing, solid lump cement pattern, and insufficient cement distributing around fracture line area were determined as risk factors by binary logistic regression analysis(P<0.05). Conclusions: The recollapse of cemented vertebrae occurrs in 12.5% of single-level OVCFs after augmentation. Preoperative osteonecrosis, solid lump pattern, and insufficient cement distributing around fracture line area probably increase the risk.