Vertebral Augmentation (Vertebroplasty/Kyphoplasty), Transpedicular Approach

Chapter 20 Vertebral Augmentation (Vertebroplasty/Kyphoplasty), Transpedicular Approach

Ryan Reeves, William A. Ante, Michael E. Frey, Michael B. Furman

Vertebral body compression fractures are estimated to occur approximately 700,000 times each year. This presents a significant public health challenge from the standpoints of morbidity, mortality, and health care expenditures. The reduction of pain, vertebral body stabilization, and rapid return to function are paramount for those who are affected with this disabling condition.

Although alternative techniques have been described, the approach described here involves the use of a trajectory view as the primary approach. The vertebral body is cannulated in the trajectory view (see Appendix 1). Figure 20–10, E, demonstrates the angulation of the needle trajectory in the lateral view with various fracture-pattern scenarios.

There are three phases of the described procedure: (1) transpedicular advancement; (2) vertebral body advancement and balloon inflation for kyphoplasty; and (3) the injection of bone cement. As is emphasized throughout this text, safety is mediated by making judicious use of multiplanar views during the procedure.

A key operational difference between kyphoplasty and vertebroplasty lies in the placement of the working cannula. During a kyphoplasty procedure, when the osteo introducer anchors 1 to 2 mm ventral to the posterior vertebral body (see Figure 20–3, A), a biopsy can be taken; alternatively, the drill can be used to create a path for the balloon tamp (see Figure 20–10, A and B). During vertebroplasty, the introducer cannula is driven from the pedicle toward the midline of the vertebral bone without additional instrumentation. When the tip of the cannula has docked into the posterior vertebral body (see Figure 20–3, A), the visualization of the tip medial to the pedicle is expected in the anteroposterior view; however, advancement should always be done in the lateral view to protect the great vessels.

The oblique transpedicular view is identical to the trajectory view (see Figure 20–1), as described previously.

Note: Please see page ii for a list of anatomical terms/abbreviations used in this book.

Transpedicular Advancement: Trajectory View (Figure 20–1)

Figure 20–1 A, Fluoroscopic image of a trajectory view with the affected L3 vertebral body “squared off” with the pedicle within the vertebral body. Cannulate the vertebral body in the trajectory view. B, Radiopaque structures. C, Radiolucent structures.

Trajectory View Safety Considerations

Avoid the spinal cord and the dural sac contents by staying lateral to the medial border of the pedicle.

Avoid the superior and inferior nerve roots and the spinal nerves by staying within the inferior and superior pedicular borders.

Avoid pneumothorax during thoracic vertebral body augmentation by avoiding the violation of the lateral wall of the vertebral body by traversing in a lateral-to-medial intrapedicular pathway.

Confirm the level (with the anteroposterior view).

Tilt the C-arm to line up the inferior endplate of the vertebral body to be treated.

Ipsilateral oblique approximately 10 to 20 degrees ipsilateral so that the pedicle appears as a clock face.

Position the pedicle in the oblique view so that it is completely encased in the outline of the vertebral body.

The transpedicular entry point is the superior lateral quadrant (i.e., the 10 or 2 o’clock position, respectively, for left or right entry) for fractures occuring along the superior endplate (majority of fractures).

– For biconcave and planar fractures, entering in the middle of the pedicle will provide optimal placement.

– For inferior endplate fractures, a 7 or 5 o’clock position for cannulation should be achieved.

Anesthetize the needle tract and periosteum overlying the pedicle.

Nick the skin (No. 11 blade for kyphoplasty or an 18-gauge needle for vertebroplasty).

Insert the osteo introducer device or the bone needle, and place the tip onto the pedicle.

Gently tap the bone needle with a mallet to create a starting hole.

Advance the needle with gentle manual pressure or mallet tapping.

Multiplanar Views During Transpedicular Advancement (Figures 20-2 and 20-3)

AP View

Anteroposterior View Safety Considerations

Avoid the spinal cord and the dural sac by keeping the osteointroducer tip lateral to the medial border of the pedicle.

Once through the pedicle the cannula tip should be seen at the posterior vertebral body wall, advance in the lateral imaging.

Tags: Atlas of Image-Guided Spinal Procedures

Dec 23, 2015 | Posted by admin in INTERVENTIONAL RADIOLOGY | Comments Off

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