Safety and Efficacy of All-In-One Percutaneous Pedicle Screw System

Abstract

Study design: Retrospective study of the prospectively collected outcomes data.

Objective: The indications for PPS placement during minimally invasive spine stabilization (MISt) procedures have increased in recent years. To the best of our knowledge, no studies have documented the outcomes of PPS insertion using the all-in-one PPS system. This study compared the conventional methods and the use of all-in-one percutaneous pedicle screw (PPS) system with respect to the speed and accuracy of PPS placement. We also determined the advantages associated with the use of the all-in-one PPS system.

Methods: We evaluated 54 patients who underwent PPS insertion using the conventional method and the all-in-one PPS system during MISt procedures. We also assessed the number of implanted PPSs, the time taken to implant PPSs, and the accuracy of PPS placement based on postoperative computed tomography images.

Results: A total of 254 PPSs were inserted (126 using the conventional method and 128 using the all-in-one PPS system). The PPS insertion time with the all-in-one PPS system (mean, 25.3 ± 9.1 s) was significantly shorter than that using the conventional method (mean, 63.1 ± 13.0 s; P < 0.01). With respect to the accuracy of PPS insertion, ≥ 2 mm pedicle breach was noted in one case each in both groups.

Conclusions: PPS placement using the all-in-one PPS system is as safe as conventional methods and has the potential to save the surgical time of MISt procedures.

Keywords: PPS; all-in-one PPS system; minimally invasive spine stabilization; percutaneous pedicle screw; thoracolumbar spine.

Figure 1.

Photograph illustrating the biplane fluoroscopy system. The symmetrical G-shaped arm, comprising 2 independent perpendicular imaging systems, provides simultaneous anteroposterior and lateral views of the surgical site.

Figure 2.

Illustration of an all-in-one PPS system. Featuring a new screw tip design and a stylet that is fully controlled by the screwdriver with the stylet control handle (allow) and the modular handle, surgeons can target pedicles and insert screws in one single instrument pass. Modified from VIPER PRIME TM System Surgical Technique.

Figure 3.

Schematic drawing illustrating of the screw insertion steps using with the All-in-one PPS system. A. Insert the inserter assembly through the incision and dock the stylet tip on the bony anatomy of the desired level. B. At initial insertion, the stylet should extend past the tip of the screw to dock onto the pedicle. Confirm the position using fluoroscopy. C. To extend the stylet relative to the screw tip, turn the stylet control handle clockwise. The screw will rise as you extend the stylet. D. Continue to advance the Stylet up to 5 mm at a time until it is fully advanced through the pedicle, up to a distance of 25 mm. E. Using a mallet, gently tap the modular handle to advance the stylet into the pedicle. Confirm the final position of the stylet using AP and lateral fluoroscopy. F. Once the stylet has been extended, hold the stylet control handle while rotating the proximal handle of the inserter clockwise to advance the screw into the pedicle over the extended stylet. G. Once the Stylet is fully retracted, the stylet control handle will no longer rotate independent of the inserter assembly. The tip of the Stylet is now approximately3 mm beyond the tip of the screw. At this point, release the stylet control handle and insert the screw the remaining distance using the proximal handle until the screw is fully seated. Modified from VIPER PRIME TM System Surgical Technique.

Figure 4.

Photograph illustrating seen from various angles the use of the conventional PPS system shown on the left and the all-in-one PPS system shown on the right. Reduction in pedicle preparation and screw insertion job steps. In the all in one PPS system, we do not need guidewires for PPS insertion.

Figure 5.

Time taken for percutaneous pedicle screw placement using the conventional methods and the all-in-one methods.

Figure 6.

Surgical instrument set of the conventional PPS system shown on the left and the All-in-one PPS system shown on the right. More organized back table with fewer instruments required and fewer instrument passes between the surgeon and the back table.