Percutaneous Pedicle Screw Fixation

The use of pedicle screws to surgically stabilize the spine is increasing in popularity. The percutaneous pedicle screw fixation (PPSF) procedure is a safe and effective treatment for many spine conditions.

How is the percutaneous pedicle screw fixation technique better than standard techniques?

According to studies, the percutaneous pedicle screw fixation procedure does not require extensive tissue dissection like standard techniques. The pedicle screw systems engage all three columns of the spine and also resist motion in various planes. Traditional procedures are associated with a lengthy hospital stay, increased costs, and extensive blood loss, but the PPSF procedure does not pose these problems.

What spine structures are involved with the percutaneous pedicle screw fixation procedure?

The percutaneous pedicle screw fixation technique stabilizes metal rods to vertebrae bones. The vertebra has a body and an arch. The body carries most of the body’s weight and forms the front wall of the spinal canal. The neural arch juts back from the body of the vertebra, and carries some of the downward load on the spine. With this procedure, the surgeon inserts small metal rods and attaches them to screws anchored into the pedicles on neighboring vertebrae.

Who is a candidate for the PPSF procedure?

Patients who require this procedure are those with back pain and radiculopathy from entrapment of an exiting nerve root within a collapsed neuroforamen (spine bone component). Most people requiring this procedure have spondylolisthesis, previous single-level spinal fusions, and degenerative spine disease.

How do I prepare for this procedure?

Before surgery, you will need to notify the surgeon of all allergies you have and what medications you take. Certain drugs that thin the blood should be avoided before surgery. You will stay in the hospital, but should arrange to have someone drive you home after discharge. Driving is not permitted for 3-4 weeks after the procedure, so you must arrange for transportation to and from the physical therapist’s office, pharmacy, and doctor’s office.

What can I expect with the surgery?

You will be given general anesthesia, which means you will feel no pain during the procedure. You will not have any memory of the surgery at all. First the surgical area of the back is cleansed with an antiseptic solution. A small incision is made over the affected spinous process, and using real-time x-ray (fluoroscopy), the surgeon locates the bony structure. Sequential dilators are used to retract the muscles and fascia. Once the tissues are moved, a probe is used to create a pedicle pilot hole.

The chosen pedicles are affixed in place using screws. The multiaxial Sextant pedicle screws are attached to extenders, which have outer and inner sleeves. The inner sleeves have a lock plug to connect to the rod, and together, these screws hold the Sextant rod. The rods are a curved shape, and they fix to the inserter forming a smooth arc. Once the extenders are aligned, the trochar tip is attached to the inserter. After supporting devices and instruments are removed, the rod/screw combination is left in place to stabilize the spine.

What clinical outcome can I expect?

The initial clinical studies using the percutaneous pedicle screw fixation procedure offer promising results. In a recent study of 12 patients, all fixation procedures were preceded by fusion. For 11 of these patients, results were considered excellent, with only one patient not having a good outcome. All patients followed for longer than 6 months had favorable clinical outcomes after PPSF.

Resources

Foley KT, Gupta SK, Justis JR, et al. (2010). Percutaneous Pedicle Screw Fixation of the Lumbar Spine. Neurosurg Focus, 10(4).