[Balloon kyphoplasty in the treatment of osteoporotic vertebral fractures: indications - treatment strategy - complications].

BACKGROUND

Considering the demographic changes in the populations of Germany and Europe as a whole, the field of geriatric traumatology is gaining more and more importance within the specialty of orthopedic and trauma surgery. The high prevalence of osteoporosis in this specific group of patients poses a special challenge, with vertebral compression fractures being the by far most common osteoporosis-related fractures. These fractures present with acute as well as chronic back pain leading to severe consequences for the affected patients. Mobility and quality of life are often heavily impaired. Furthermore, higher morbidity and mortality as well as higher risk for further fractures have been proven in these patients.

METHOD

Balloon kyphoplasty has become a more frequently used therapy and is now offered broadly. This treatment addresses stable fractures not involving the posterior margin of the vertebrae. With increasing application of this surgical procedure the number of complication reports is also rising. The following article gives an overview of the technique, indications and the possible complications by giving several examples from the daily practice and reviewing the relevant literature.

RESULTS

Cement leakage of the treated vertebrae is the most common complication associated with balloon kyphoplasty. In almost all cases this occurs due to too early application of the cement, not having reached its optimum in viscosity. Literature research shows a percentage rate of about 9% for cement leakage. Thus, balloon kyphoplasty provides more safety for the patient than vertebroplasty, for which cement leakage rates of up to 41% are reported. Other studies report cement leakage ratios of 4-10% for kyphoplasty versus 20-70% for vertebroplasty. Overall the percentage of cement leakage is clearly increased in osteoporotic fractures compared to non-osteoporotic fractures, with the cement leaking mainly into the spinal disc space. So far, valid data in order to further explore the consequences of intradiscal cements are lacking. Most relevant for everyday practice are cement leakages that have become symptomatic. Depending on the localisation they present with dysaesthesia culminating in radicular pain or even paraplegia. Cement leakage into vessels can, depending on the amount of cement, lead to embolism of pulmonary arteries. Complications due to the surgical technique, postoperative infections, bleeding or cardiovascular complications are rare with less than 1%. The probability for symptomatic cement leakage averages about 1.3% for balloon kyphoplasty. Another discussion, for which at present there is no evidence-based verification, is concerned with the higher risk for adjacent vertebral fractures after cement augmentation of an osteoporotic vertebral compression fracture. At present the degree of osteoporosis and more important the number of osteoporosis-related fractures must be the relevant predictor for adjacent fractures of neighbouring vertebrae.

CONCLUSION

Balloon kyphoplasty is a highly standardised and widely used minimally invasive procedure for stabilising and augmenting painful osteoporotic fractures of the vertebral body. When surgery is indicated carefully and is carried out subtly, the risk of complications is reasonable and the outcome is promising. Viscosity of the used cement has to be adequate and it must not be inserted with too high a pressure. A causal connection between cement viscosity and risk of cement leakage has been proven in experimental studies. During application of PMMA cement a thorough fluoroscopic monitoring must take place in order to detect cement leakage at an early stage and if necessary stop application. These procedures should be reserved for clinical centres and surgeons who are able to surgically handle possible complications such as compression of the spinal cord. On the basis of our own experience we also recommend treatment in a hospital with an integrated osteoporosis centre and consecutive treatment in specialised outpatient care. Standards in primary care as well as after treatment can be introduced thereby. Also communication with practitioner concerned with outpatient care is simplified, which leads to enduring therapeutic outcome.