32 Minimally Invasive Treatment of Vertebral Body Fractures (original) (raw)

Gestures rather harmless at first sight like weight-lifting , a sudden movement, sometimes only remaking the bed in the morning could cause, in susceptible individuals, the failure and collapse of the vertebral body. Painful fractures, which cause changes in appearance and posture, persistent back pain, limited mobility and a general decay in the affected individuals, most often even unaware of the cause of their evil (Eastell et al., 1991). One of the most frequent causes of fractures of the vertebral body is osteoporosis (Dempster, 2011; Haczynski, 2001), relentless and "silent" disease spread rapidly, due to an aging world population. Vertebral fractures can also be the result of a traumatic event, of hematologic malignancies(multiple myeloma, leukemia), solid tumor metastases to the spine (Bouvard et al., 2011) or long-term steroid therapy(treatment of rheumatoid arthritis, post-transplant patients)(Naganathan et al., 2000). Despite the persistent pain and a more accentuated thoracic and lumbar deformities, those affected often find it hard to realize it , confusing the symptoms with a simple back pain. A compression fracture of the vertebral body not properly treated, increases by 5 times the risk of further fractures, with all that entails in terms of quality of life of the patient and health and social costs (Oleksik et al., 2000). Usually, in case of spinal pain from vertebral fracture, the patient underwent conservative treatment, covering the prescription of a rigid bust, prolonged immobilization and antiinflammatory medication and painkillers (Prather et al.,2007). A similar solution, however, may not always be sufficient to solve the problem, because the pain can persist for several months and, above all, the patient does not recover the correct posture with increased comorbidity (Cauley et al., 2000) Currently there are minimally invasive methods, such as balloon kyphoplasty, vertebroplasty, and other percutaneous techniques for stabilization, inherently safe for characteristics and dynamics of action, allowing an immediate relief of the pain, and ensuring a good recovery of the statics of the spine (Frank, 2003). 2. Spine anatomy The spine consists of 33 vertebrae, including 7 cervical, 12 thoracic, 5 lumbar, 5 sacral segments often fused together, and finally 4 coccygeal segments (Gray, 1973). These segments are spaced by the intervertebral discs and structurally connected by ligaments and muscles. Observed in the lateral projection, a normal spine shows lordosis at the cervical www.intechopen.com Osteoporosis 650 and lumbar regions and a mild kyphosis at the thoracic and sacral regions. These variations in the curvature are important because they are responsible for the orientation of the single vertebra and important components such as the vertebral pedicles, which are the main access route of percutaneous stabilization techniques which will be discussed later(Ortiz & Deramond, 2001). The size of the vertebrae gradually increase from cervical to lumbar tract with variability dependent on the size of the individual. Theoretically there is an increase in volume ranging from 7.2 ml of the cervical area to 22.4 ml of the lumbar spine. In the thoracic area vertebrae are connected bilaterally with the ribs by ligaments that go from the head of the rib to the vertebral body and then from the rib to the vertebral transverse process. The pedicles of the lower thoracic are relatively large and oriented in an anteriorposterior direction. Heading toward the upper tract, we observe a progressive reduction in the size of the pedicles whose orientation becomes more oblique. In the lumbar tract, we observe larger vertebrae and the orientation of the pedicles is different as we go from L1 to L5. The pedicles of the lumbar spine than have a straight anterior-posterior direction similar to that of the lower thoracic. The pedicles tend therefore to be more oblique in the lower lumbar vertebrae reaching their maximum inclination at L5 (fig. n. 1).