Osteoporosis is a disease of the bone characterized by a decrease in bone density, causing an increased risk of fracture. In the European Union only, 117 fractures/100 000 inhabitants are caused by osteoporosis.
Vertebral compression fractures may occur after trauma or falls, but even after benign movements such as bending or standing up. They cause pain requiring hospital admission, bed rest as gait is often impossible and in some cases compression of spinal cord and spinal nerve roots, spine deformity and difficulties breathing by loss of thoracic expansion. The patient may then move towards a spiral of degradation of mobility and of quality of life. The mortality rate of such patients is therefore increased by 30% when compared to a normal population of the same age.
Classic treatment of the vertebral osteoporotic compression fracture was until recent days made of bed rest, painkillers and braces, and when required, of surgery, mainly tailored laminectomy if the nervous structures were endangered. These treatment were sometimes difficult to accept by the patient and insufficient to control pain. New technologies have therefore been developed.
This is how kyphoplasty became part of the therapeutic options to treat vertebral compression fractures. This operation aims toward relieving the pain by stabilizing the fracture, and towards decreasing the deformity by restoring the vertebral height. It involves placing two trocard needles in the vertebral body of the fractured vertebra, usually through the pedicles. This is performed percutaneously and under fluoroscopic control, under local or general anaesthesia. A balloon is then inflated in the vertebra, allowing reduction of the fracture. The balloons are then removed. This creates a space which will be filled with bone cement (PMMA or calcium phosphate) injected under low pressure. This allows fracture stabilization and permanent correction of deformity. The whole procedure takes between 30 and 45 minutes for each treated vertebra.
This technique is indicated in symptomatic thoracic or lumbar osteoporotic compression fractures. Some cases of traumatic fractures on healthy bone or some oteolytic tumoral fractures may also be treated this way.
The preoperative radiological assessment will often involve magnetic resonance imaging of the spine and/or bone scintigraphy. This allows us to determine the age of one particular fracture in case of multiple lesions and to focus on the treatment of this symptomatic vertebra, leaving the more ancient silent and stabilized vertebras untreated as they should be.
Kyphoplasty is not indicated in cases of coagulation disorders, pregnancy, infections, multifragmented fractures (particularly if one fragment of bone may compress the nervous structures) and hyperosseous metastases (as in prostate cancer). The complication rate is very low (reported less than 2%). Problems are usually encountered if the vertebra is poorly vizualized, thus increasing the risk of a wrong positioning of the trocard needle in the vertebra. On rare occasions, extravasation of cement out of the vertebral body may occur.
The efficacy of kyphoplasty on pain is really remarkable (95% immediate success). Partial correction of the deformity is obtained in 70% of the patients, particularly when the facture is treated without delay. On a more ancient fracture, although the procedure still allows pain control, deformity correction is more difficult to obtain.
In conclusion, although kyphoplasty may not be the treatment of the osteoporotic disease (which remains a medical long term treatment), it is more and more considered a efficient and low risk treatment of the vertebral osteoporotic (and sometimes traumatic or tumoral) compression fracture.
