Fiabilidad del navegador en la colocación de tornillos pediculares toracolumbares

Evaluation of the implantation of transpedicular screws in spinal instrumentation with free-hand technique and navigation-assisted with intraoperative computed tomography: An analytical-positional study

BACKGROUND

Spinal instrumentation using transpedicular screws has been used for decades to stabilize the spine. In October 2018, an intraoperative CT system was acquired in the Neurosurgery service of the University Hospital Complex of Vigo, this being the first model of these characteristics in the Spanish Public Health System, so we began a study from January 2015 to December 2019 to assess the precision of the transpedicular screws implanted with this system compared with a control group performed with the classical technique and final fluoroscopic control.

METHODS

The study was carried out in patients who required transpedicular instrumentation surgery, in total 655 screws were placed, 339 using the free-hand technique (Group A) and 316 assisted with intraoperative CT navigation (Group B) (p>0.05). Demographic characteristics, related to surgery and the screw implantation grades were assessed using the Gertzbein-Robbins classification.

RESULTS

92 patients were evaluated, between 12 and 86 years (average: 57.1 years). 161 thoracic screws (24.6%) and 494 lumbo-sacral screws (75.4%) were implanted. Of the thoracic screws, 33 produced a pedicle rupture. For the lumbo-sacral screws, 71 have had pedicle violation. The overall correct positioning rate for the free-hand group was 72.6% and for the CT group it was 96.5% (p<0.05).

CONCLUSION

The accuracy rate is higher in thoracic-lumbar instrumentation in the navigation group versus free-hand group with fluoroscopic control.

Evaluation of the implantation of transpedicular screws in spinal instrumentation with free-hand technique and navigation-assisted with intraoperative computed tomography: An analytical-positional study

BACKGROUND

Spinal instrumentation using transpedicular screws has been used for decades to stabilize the spine. In October 2018, an intraoperative CT system was acquired in the Neurosurgery service of the University Hospital Complex of Vigo, this being the first model of these characteristics in the Spanish Public Health System, so we began a study from January 2015 to December 2019 to assess the precision of the transpedicular screws implanted with this system compared with a control group performed with the classical technique and final fluoroscopic control.

METHODS

The study was carried out in patients who required transpedicular instrumentation surgery, in total 655 screws were placed, 339 using the free-hand technique (Group A) and 316 assisted with intraoperative CT navigation (Group B) (p>0.05). Demographic characteristics, related to surgery and the screw implantation grades were assessed using the Gertzbein-Robbins classification.

RESULTS

92 patients were evaluated, between 12 and 86 years (average: 57.1 years). 161 thoracic screws (24.6%) and 494 lumbo-sacral screws (75.4%) were implanted. Of the thoracic screws, 33 produced a pedicle rupture. For the lumbo-sacral screws, 71 have had pedicle violation. The overall correct positioning rate for the free-hand group was 72.6% and for the CT group it was 96.5% (p<0.05).

CONCLUSION

The accuracy rate is higher in thoracic-lumbar instrumentation in the navigation group versus free-hand group with fluoroscopic control.

Accuracy of Current Techniques for Placement of Pedicle Screws in the Spine: A Comprehensive Systematic Review and Meta-Analysis of 51,161 Screws

BACKGROUND

Pedicle screws (PSs) are routinely used for stabilization to enhance fusion in a variety of spinal diseases. Although the accuracy of different PS placement methods has been previously reported, most of these studies have been limited to 1 or 2 techniques. The purpose was to determine the current accuracy of PS placement among 4 modalities of PS insertion (freehand [FH], fluoroscopy-assisted [FA], computed tomography navigation-guided [CTNav], and robot-assisted [RA]) and analyze variables associated with screw misplacement.

METHODS

A systematic review was performed of peer-reviewed articles reporting PS accuracy of 1 technique from January 1990 to June 2018. Accuracy of PS placement, PS insertion technique, and pedicle breach (PB) data were collected. A meta-analysis was performed to estimate the overall pooled (OP) rates of PS accuracy as a primary outcome, stratified by screw insertion techniques. Potential determinants were analyzed via meta-regression analyses.

RESULTS

Seventy-eight studies with 7858 patients, 51,161 PSs, and 3614 cortical PBs were included. CTNav showed the highest PS placement accuracy compared with other techniques: OP accuracy rates were 95.5%, 93.1%, 91.5%, and 90.5%, via CTNav, FH, FA, and RA techniques, respectively. RA and CTNav were associated with the highest PS accuracy in the thoracic spine, compared with FH.

CONCLUSIONS

The OP data show that CTNav has the highest PS accuracy rates. Thoracic PSs were associated with lower accuracy rates; however, RA showed fewer breaches in the thoracic spine compared with FH and FA. Given the heterogeneity among studies, further standardized and comparative investigations are required to confirm our findings.

Pediatric Lumbar Pedicle Screw Placement Using Navigation Templates: A Cadaveric Study

BACKGROUND

Pedicle screw technique is commonly used treatment of adult spinal trauma, tumor, degeneration. The application of pedicle screws is very challenging in children because children have a fast growing spine and spinal pedicle morphology of children and adult has large difference. 3 D reconstruction individual navigation templates improve the success rate of pediatric pedicle screw system. This study is aimed to provide a precise method for lumbar spine pedicle screw placement in children using computer-aided design and rapid prototyping technology.

MATERIALS AND METHODS

Computed tomography (CT) scans of cadaver specimens of 4 children were obtained, and the raw data were reconstructed using three-dimensional reconstruction software. Pedicle screws were placed using the conventional method or by using individually designed navigation templates based on the principles of reverse engineering and rapid prototyping technology.

RESULTS

We evaluated the accuracy of the pedicle screws placed using the two methods by CT scan. Ten navigation templates were designed for placement of 20 lumbar pedicle screws in the navigation group, and CT scan confirmed that all the screws were placed accurately in the corresponding pedicle. Conversely, of the 20 lumbar pedicle screws placed using the conventional method, 3 screws perforated the pedicle. The findings showed that lumbar pedicle screw placement was successful using navigation templates in children.

CONCLUSIONS

This technique is simple, easy to master, and allows personalized screw placement, thus providing a new and feasible method for lumbar pedicle screw placement in children.

A brief overview of 100 years of history of surgical treatment for adolescent idiopathic scoliosis

The history of surgical correction for adolescent idiopathic scoliosis reaches back about 100 years: the natural course of progressive, crippling and sometimes even life-threatening deformities which could not be controlled by external means called for effectual, invasive procedures. Hibbs 1911 aimed at halting progression by long, uninstrumented fusions. However, the lack of true correction, long rehabilitation times, high pseudarthrosis and infection rates, and a fusion mass which bent further once exposed to gravity again were not satisfying. The transition from slowing progression to halting progression and truly correcting the deformity lasted almost another half a century: Paul Harrington, confronted with many scoliotic polio patients, successfully introduced a hook-rod system for concave-distraction and convex-compression at the end of the 1950s. Many implant failures, a still-considerable pseudarthrosis rate, flattening of the sagittal profile and the lack of true three-dimensional (3D) correction were the shortcomings. In the 1970s the Frenchmen Cotrel and Dubousset took scoliosis surgery to the next level by introducing a versatile hook system and curve-pattern-adapted correction modes. The basics of the so-called derotation-manoeuvre consists in strategic distribution of the anchors along the curve, bending the rod accordingly, and rotating it back into the sagittal plane. The overall correction, stability and the fusion rates improved significantly. However, the effect on the sagittal and transverse plane were still limited. Lately, a better biomechanical understanding and bilateral, polysegmental strong three-column fixation with pedicle screw has become the benchmark method: in conjunction with posterior release techniques, osteotomies or even vertebral column resections for severe cases, it allows better 3D control (vertebral column manipulation), faster rehabilitation and better patient satisfaction.