A new method to precisely control the depth of percutaneous screws into the pedicle by counting the rotation number of the screw with low radiation exposure: technical note

20 Tips to Avoid and Handle Problems in the Placement of Percutaneous Pedicle Screws

BACKGROUND

Two-dimensional fluoroscopy-guided percutaneous pedicle screw placement is currently the most widely applied instrumentation for minimally invasive treatment of spinal injuries requiring stabilization. Although this technique has advantages over open instrumentation, it also presents new challenges and specific complications. The objective of this study was to provide recommendations developed from the experience of several spinal surgeons at different minimally invasive spine surgery reference centers to solve specific problems and prevent complications during the learning curve of this technique.

METHODS

An AO Spine Latin America minimally invasive spine surgery study group analyzed the most frequent complications and challenges occurring during the placement of >14,000 two-dimensional fluoroscopy-guided percutaneous pedicle screws at different centers over 15 years. Twenty tips considered most relevant to performing this technique, excluding problems directly related to specific brands of instruments, were presented.

RESULTS

The 20 tips included the following: (1) positioning; (2) clean and painless; (3) fewer x-rays; (4) check the clock; (5) beveled tip; (6) transverse-rib-pedicle; (7) double Jamshidi; (8) hammer the Kirschner wire; (9) bent tip; (10) too loose, too tight; (11) new trajectory; (12) manual control; (13) start over; (14) Kirschner wire first; (15) adhesive drape control; (16) bend the rod; (17) lower rods; (18) freehand inner; (19) posterior fusion; (20) revision.

CONCLUSIONS

Implementation of these tips might improve performance of this technique and reduce the complications related to percutaneous pedicle screw placement.

Percutaneous endoscopic unilateral laminotomy and bilateral decompression under 3D real-time image-guided navigation for spinal stenosis in degenerative lumbar kyphoscoliosis patients: an innovative preliminary study

BACKGROUND

The aim of this study is to introduce a new method of percutaneous endoscopic decompression under 3D real-time image-guided navigation for spinal stenosis in degenerative kyphoscoliosis patients without instability or those who with multiple comorbidities. Decompression alone using endoscope for kyphoscoliosis patient is technical demanding and may result in unnecessary bone destruction leading to further instability. The O-arm/StealthStation system is popular for its ability to provide automated registration with intraoperative, postpositioning computed tomography (CT) which results in superior accuracy in spine surgery.

METHODS

In this study, we presented four cases. All patients were over seventy years old female with variable degrees of kyphoscoliosis and multiple comorbidities who could not endure major spine fusion surgery. Percutaneous endoscopic unilateral laminotomy and bilateral decompression under 3D real-time image-guided navigation were successfully performed. Patients' demographics, image study parameters, and outcome measurements including pre- and post-operative serial Visual analog scale (VAS), and Oswestry Disability Index (ODI) were well documented. The follow-up time was 1 year.

RESULTS

Pre- and post-operative MRI showed average dural sac cross sectional area (DSCSA) improved from 81.62 (range 67.34-89.07) to 153.27 (range 127.96-189.73). Preoperative neurological symptoms including radicular leg pain improved postoperatively. The mean ODI (%) were 85 (range 82.5-90) at initial visit, 35.875 (range 25-51) at 1 month post-operatively, 26.875 (range 22.5-35) at 6 months post-operatively and 22.5 (range 17.5-30) at 12 months post-operatively (p < 0.05). The mean VAS score were 9 (range 8-10) at initial visit, 2.25 (range 2-3) at 1 month post-operatively, 1.75 (range 1-2) at 6 months post-operatively and 0.25 (range 0-1) at 12 months post-operatively (p < 0.05). There was no surgery-related complication.

CONCLUSIONS

To the best of our knowledge, this is the first preliminary study of percutaneous endoscopic laminotomy under O-arm navigation with successful outcomes. The innovative technique may serve as a promising solution in treating spinal stenosis patients with lumbar kyphoscoliosis and multiple comorbidities.

Marked Guidewire Technique Prevents Complications of Percutaneous Pedicle Screws and Precisely Controls Depth: Technical Note

OBJECTIVE

We sought to describe a novel modified guidewire technique used in the placement of percutaneous pedicle screws (PPSs), which enables safe and precise control of the depth of screw placement and prevents excessive advancement of the guidewire with low radiation exposure. PPSs have been widely used and have many advantages. However, inadvertent advancement of the guidewire may damage peripheral tissue or viscera, and repeated confirmation of the depth of screw and guidewire leads to extensive radiation exposure.

METHODS

A modified guidewire with markers was used intraoperatively. The reading of the mark on the guidewire increased as the PPS advanced into the pedicle. The depth of the screw in the pedicle was calculated as the mark reading after each screw was rotated into the pedicle minus the initial mark reading. After all pedicle screws were placed, the positions of the screws were checked by C-arm or G-arm fluoroscopy.

RESULTS

The modified guidewire was applied in 41 thoracic-lumbar fracture patients. The depths of the percutaneous screws were precisely controlled as planned. There were no inadvertent breaches of the anterior cortices of the vertebrae. No patients reported neurologic symptoms, and there was no screw misplacement detected. Surgeons had no radiation exposure, and patients were only exposed once to the radiation.

CONCLUSIONS

The modified guidewire with markers is an effective device to precisely control the depth of PPSs and prevent complications of the guidewire in the placement of pedicle screws.