Evidence & Methods
Adjacent level fractures following vertebrolasty and kyphoplasty are common and can be problematic. In this study, the authors explore possible risk factors.
In this relatively small prospective study that examined several potential risk factors for adjacent level fractures, only Hypovitaminosis D and cement leakage from the prior kyphoplasty were found to be risk factors.
The findings suggest that both technical and metabolic factors present risk. Importantly, both are somewhat controllable, either by vitamin supplementation or by technique modification.
—The Editors
Vertebral compression fractures are among the most common complications of osteoporosis with significant socioeconomic consequences. An estimated 750,000 new vertebral fractures occur in the United States every year [1], whereas the burden of health management exceeds $700 million [2].
The vertebral fractures affect the patient's overall health because of the direct and indirect effects on quality of life with increased morbidity and mortality [3], [4], [5], [6], [7], [8], [9], [10], [11]. Pain associated with vertebral fractures limits mobility of the patients and subsequently leads to depression and loss of self-independence [12], [13], [14].
The presence of one or more vertebral fractures increases the risk of a new vertebral fracture by five-fold, although the incidence of a new vertebral fracture in the following year is approximately 20% [15], [16].
Despite medical approach [17], as many as one-third of patients with vertebral fractures continue to experience severe pain that can lead to further disability [18] that requires long-term care and hospitalization.
Over the past 20 years, methods of minimally invasive surgery have been developed, including vertebroplasty and kyphoplasty. The technique of vertebroplasty consists of fluoroscopically guided percutaneous insertion of a needle into the fractured vertebra and injection of polymethylmethacrylate cement. Kyphoplasty differs from vertebroplasty in that it involves the insertion of a balloon tamp [19]. The balloon tamp intends to reduce the deformity, to restore the vertebral body height while creating a cavity to be filled with polymethylmethacrylate. The complications of these techniques are bleeding, transitory increase in pain, cement leakage, spinal infection, rib fractures, symptomatic or asymptomatic pulmonary embolism, radiculopathy, and spinal cord compression from the extravagation of the cement. Balloon kyphoplasty and vertebroplasty are also associated with a recurrent fracture risk in the adjacent levels within a short period of time after the surgical procedure [19].
In recent years, there has been increasing interest regarding the incidence of recurrent vertebral fractures after each type of procedure and possible reasons for their occurrence. A number of variables, such as the number of levels treated, the age, the gender, the cement leakage, the role of intervertebral disc, the unipedicular or bipedicular kyphoplasty, the sagittal alignment, the amount or the type of cement injected, the bone mineral density measurements, and several other factors [20], [21], [22], [23], [24], [25], [26], [27], [28], [29], have been evaluated by several studies in the development of the recurrent fractures and in the overall clinical outcome. At the present time, there are little and insufficient data concerning the evaluation of the metabolic profile of the patients who undergo kyphoplasty [30].
The present study was undertaken to evaluate the incidence of recurrent fractures after kyphoplasty and identify any association between these fractures and the metabolic risk factors.