Vertebroplasty

Procedure
Percutaneous vertebroplasty may be performed to augment collapsed vertebrae at various levels of the dorsal spine. Most clinical experience is in the thoraco-lumbar region, however, cervical vertebrae can also be treated. Sedation along with local anesthesia allow for monitoring of the patient's neurological status during the procedure; alternatively, general anesthesia may be used. One or two large bore needles are placed under X ray guidance inside the body of the vertebral body.

When the needle position is satisfactory, the prepared injectable compound (such as PMMA) is mixed with radio-opaque barium sulfate or tantalum powder to increase fluoroscopic visibility. Because of the high viscosity of PMMA, it is necessary to inject the material via several small (1-2 cc) syringes. The material is injected into the vertebral body, under continuous fluoroscopic monitoring. The lateral view is especially important because of the risk of leakage of cement into the spinal canal or neural foramina. Leakage may occur through venous channels, lytic posterior body wall lesions, or an iatrogenically perforated medial pedicle wall. Injection is stopped when cement reaches the posterior wall on a lateral view, or when it is seen to enter parts of the vertebral venous plexus, where venous embolism to the lungs is a theoretical concern. Pre-procedure CT scanning helps to identify anatomical features predisposing to leakage, such as lytic cortical defects. Leakage through endplates into the disk space has been noted to be asymptomatic and inconsequential. Leakage into the paravertebral soft tissues can potentially threaten the femoral nerve when the procedure is performed in the lumbar region, and the intercostal nerves during procedures at the thoracic level.

Injection may be uni- or bi-pedicular, and typically up to 2-3 levels are treated in one session. Afterward, the patient is positioned supine and observed carefully for 24 hours in the hospital. Immediate post-procedure CT scan and plain films are reviewed for leakage. Common side effects include post-procedure fever, which is thought to be an inflammatory response to the cement, and is treated with non-steroidal medications. Transient exacerbation of pain, also thought to be mediated by inflammation, can occur. New paresthesias or partial motor deficits on post-procedure exam are treated with steroids in the absence of obvious physical compression of the nerve roots or spinal cord by cement leakage. If any leakage associated with a neurological change or deficit is detected during or after the procedure, a stand-by orthopedic or neurosurgical team must be available to decompress the neural elements and remove the leaked cement. There have been a few reported instances of this serious complication. Hospitalization averages between 1-2 days. Patients are allowed to get out of bed and bear full weight the day after the procedure.

Medical Dictionary
Please see also our Resource page for additional information