Early studies performed vertebroplasty only after conventional treatment (medication and rest) had failed.⁸ Later series have advocated treatment as early as weeks or days if the patient requires narcotic medication or admission to hospital secondary to pain. Others have recommended vertebroplasty within 4 months.³ Although late treatment is unlikely to be successful, there are case reports of patients being successfully treated after a few years.⁹

Even though some believe it is a reasonable indication,¹ there are insufficient data to categorically support the treatment of painful tumor infiltration without fracture. In addition, it is unclear whether to treat before or after radiation therapy. Injection of cement into the vertebral body will likely dislodge marrow elements that could potentially be absorbed into the blood stream. This concern for causing metastatic dissemination suggests that vertebroplasty should be performed only after radiation therapy.

Prophylactic vertebroplasty is neither widely accepted nor approved for osteoporotic vertebral compression fractures and no studies have been done to substantiate the utility of this practice.¹

TECHNIQUE

1. Pre-procedure planning. MRI, computed tomography (CT), and X-ray images of the fracture are evaluated in all views specifically looking for the angle of approach to the vertebra through the pedicle. Because normal anatomy (Fig. 32.1) is altered by the fractures, the approach to the body of the vertebra through the pedicle is altered. This altered bone architecture must be carefully analyzed by reviewing all the available radiological films. Specifically, the cortical margins of the bone are reviewed in anteroposterior (AP), lateral, and axial views to preplan the pathway of the trocar to the exact target area within the vertebral body. The angle will be altered based on the characteristics of the fractured vertebra. The vertebra may be approached through one pedicle or both pedicles. If the angle of insertion is achieved in such a way that the tip of the trocar is in the center of the body, then one may use a single-pedicle approach. If the trocar lies on one side of the body of vertebrae, then the other pedicle may be used to approach the other side of the vertebral body.

2. Prior food and medication. For procedure performed in the morning, the patient is informed not to eat or drink after midnight, but is allowed to take medications. When conscious, sedation is used for a procedure to be done later in the day, and the patient should not drink or eat for a minimum of 4 hours beforehand. Diabetics and other chronic medical illness management including the timing of anticoagulants should be coordinated with the primary care physician.

3. Prophylactic antibiotics. Intravenous antibiotics (cefazolin 1 g) are given 30 minutes before the procedure. Ciprofloxacin 500 mg orally twice a day may be given, if the patient is allergic to other medications and should be started 12 hours before the procedure and continued 24 hours after completion of the procedure.⁶

Fig. 32.1 Pedicles. (A) Axial view. (B) Lateral view.

We do not give any prophylactic antibiotics and prescribe antibiotics postoperatively for a week.

4. Position of patient. The patient is placed in a prone position for surgery in the thoracic and lumbar region and supine for cervical region.³ It is critical to confirm the level of pain and fracture under fluoroscopy before beginning vertebroplasty.¹ Applying pressure with the thumb or palm of the hand over each spinous process or side-to-side movement of the spinous process will often elicit tenderness. As the patient is awake during the procedure and placed in a prone position, the patient should be made comfortable with padding and arm supports.

5. Anesthesia. Percutaneous vertebroplasty is performed using local anesthesia typically combined with neuroleptanalgesia ^2,^3,^5,^10,¹¹ or general anesthesia.^10,^11,¹² The authors use a combination of intravenous midazolam (Versed; Roche, Manate, Puerto Rico) and fentanyl (Sublimaze; Abbott Laboratories, North Chicago, IL).^13,¹⁴ Dosages are based on patient size and condition and can be titrated during the procedure based on the patient’s response. General anesthesia is rarely used for this procedure. Two to 3 ml of 1% solution of lidocaine injected into the marrow through the needle will relieve pain, which some patient may experience when cement is injected into the bone.^6,¹⁵

6. Prepping and draping. The skin is prepared with iodine and then draped. As the position is checked many times in AP and lateral views, the field of procedure should be well protected with sufficient drapes.

7. CT scan versus C-arm fluoroscopy. Vertebroplasty is performed using biplanar fluoroscopy,^3,¹¹ C-arm fluoroscopy, and dual-guidance CT.^3,¹⁶ CT is only used for extremely difficult cases, such as tumor destruction of the posterior vertebral wall⁶ or vertebra plana.¹⁷ When using a single-plane C-arm fluoroscopy all the movements during the procedures should be confirmed in two planes, AP and lateral.

8. Approach to the vertebral body. Cervical vertebroplasty has been done with transoral approach,^18,¹⁹ lateral, and anterolateral approach.²⁰ The authors do, however, have concerns about the transoral approach. This technique necessitates traversing the oropharynx which is riddled with bacteria ready to flourish in the vertebral body. Consequently, we prefer the anterolateral approach used by Deramond in the first described vertebroplasty procedure.²¹ As osteoporotic fractures are rare in the cervical area, vertebroplasty is rarely done in the cervical region except for conditions such as tumors. During the needle placement one must be careful to avoid the carotid artery and internal jugular vein.⁶ Both structures are displaced laterally and the esophagus and trachea medially to reach the body of cervical vertebrae (Fig. 32.2).

Fig. 32.2 Cervical body, anterior.

The thoracic and lumbar vertebral bodies are usually approached through one or, most commonly, both pedicles.^2,^8,²¹^–²⁷ Various approaches are used including a costovertebral,⁵ paravertebral, posterolateral, or anterolateral (cervical) approach. The parapedicular or transcostovertebral²⁸ approach is used when a transpedicular approach cannot be used because of small pedicles, a fractured pedicle, or tumor invading the pedicle. Like most physicians, the authors prefer the transpedicular approach instead of the parapedicular approach, which may increase the chance of both a pneumothorax and that a paraspinous hematoma may not be controlled with application local pressure.⁶ The posterolateral approach increased the risk of injuring the exiting nerve root and segmental artery,⁶ and has largely been abandoned although some authors recommend it for lumbar vertebrae.^20,^23,²⁸

There are many companies which supply cement and delivery equipment: Parallax Medical Inc./Arthrocare Corporation; Cook Group Inc.; Interpore Cross International Inc.; Interpore Cross International Inc./American OsteoMedix Corp.; Medtronic Inc./Medtronic Sofamor Danek; Orthofix International NV/Orthofix Inc.; Stryker Corp.; Tecres SPA.²⁹ These sets contain stylets, needles, tubing, injectors, and injector barrels, but the end result is the same. The equipment allows one to inject cement into the anterior part of the vertebral body. Some authors have, however, modified the equipment and technique,³⁰^–³³ and before these sets were available, operators recommended using 1 mL syringes for injection of cement.^7,^11,^17,²⁴

9. Needle insertion. Mark a point on the skin after viewing the fractured vertebra in the anteroposterior and lateral views. This is the planned insertion site of the cannula. The initiation site should correspond with superolateral aspect of the pedicle. It should not be near the inferior or medial margins of the pedicle. Local anesthetic is infiltrated into the skin, subcutaneous tissue, and up to the periosteum of the pedicle. We inject 2–3 mL of lidocaine 1% with 25-gauge 1.5 inch needle for local anesthesia (Fig. 32.3).

Fig. 32.3 Injecting local anesthetic.

A small incision is made using a No. 11 knife blade and the introducer needle from the set is inserted (Fig. 32.4). A 15-gauge needle is used for cervical vertebrae and 10-gauge for thoracic and lumbar vertebrae.³ Currently, even thinner needles (13-gauge) are being used.⁶ The needle entry site is localized in the AP view. The authors use a diamond-tipped needle to start the entry.