Associated risk factors for cemented vertebral body re-wedge after percutaneous kyphoplasty

Abstract

Objective To investigate the related risk factors of the previous cemented vertebral body re-wedge after percutaneous kyphoplasty (PKP). Methods In this retrospective case-control study, clinical data of 617 patients treated by PKP from December 2008 to November 2014 were analyzed. According to whether the cemented vertebra wedged again, the patients were divided into cemented vertebral re-wedge group (n=12) and non-cemented vertebral re-wedge group (n=605). The data of age, preoperative bone density, preoperative vertebral osteonecrosis, intraoperative bone cement injection amount, postoperative bone cement leakage, postoperative bone cement filling, postoperative recovery rate of vertebral wedge angle, and presence or absence of adjacent old vertebral wedging were recorded in two groups. All patients were followed up for one year, and the data were summarized and statistically analyzed. Results Single factor analysis showed the factors of whether there were adjacent old vertebral wedge, preoperative vertebral osteonecrosis, cystic bone cement filling, different wedge angle recovery rate, and emergence of previous cemented vertebral body re-wedge after PKP were statistically significant between two groups (P 0.05). Multivariate Logistic stepwise regression analysis showed cystic bone cement filling, preoperative vertebral osteonecrosis, adjacent old vertebral wedging, and higher recovery rate of vertebral wedge angle were prone to appear previous cemented vertebral body re-wedge (P<0.05). Conclusions Relatively higher recovery rate of vertebral wedge angle, previous adjacent old vertebral wedge, vertebral osteonecrosis, and cystic bone cement filling are risk factors closely related to cemented vertebral re-wedge after PKP, which gives a good reference to assess surgical risk, avoid risk factors and choose right surgical techniques. Key words: Fractures, compression; Thoracic vertebrae; Lumbar vertebrae; Percutaneous kyphoplasty