Vertebroplasty for adjacent vertebral fracture following lumbar interbody fusion

Purpose. Adjacent segment vertebral compression fracture after lumbosacral instrumented fusion has been reported to be a significant complication. Recently, percutaneous vertebroplasty (PVP) has been widely used for the treatment of non-traumatic osteoporotic vertebral fracture. However, the clinical effect of this minimally invasive treatment option to the post-fusion vertebral fracture has rarely been reported. We analysed characteristics of adjacent vertebral fractures following lumbar fusion and evaluated the clinical outcome of PVP. Methods. A total of 202 consecutive patients underwent PVP for compression fracture in our institute between January 2007 and December 2008. Among them, nine symptomatic adjacent vertebral fractures following lumbar fusion were identified. We randomly selected 50 control patients undergoing vertebroplasty for osteoporotic compression fracture in single level. We analysed the clinical data according to age, height, body weight, body mass index (BMI), and bone mineral density (BMD). Clinical outcome was assessed by a visual analogue scale (VAS) score and the rate of overall satisfaction. Results. Fractures occurred at the cranial adjacent vertebra after fusion surgery in all cases. The mean BMD score for the spine and femur were significantly higher than the control group (p < 0.05). After PVP, the mean VAS score improved from 8.1 to 3.2. The overall satisfaction rate was 88.9%. Other constitutional factors and clinical outcomes were similar to the control group. Conclusion. Adjacent vertebral fracture following lumbar fusion may occur as a kind of adjacent segment disease. The increased stress around the fusion segment can cause vertebral fracture even with a relatively higher BMD score. Vertebroplasty for the post-fusion vertebral fracture can be as effective as it is for the usual osteoporotic vertebral fracture.