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The surgical procedure of pedicle screw insertion with the assistance of rapid prototyping navigation template. (a) The navigation templates fit closely to the posterior surface of corresponding vertebral body. (b) A high-speed drill bit was used to drill channels through navigation template. (c) The cervical specimen and corresponding physical vertebra model. (d) Pedicle screw insertion into the cervical specimen through designed screw channels.
Source publication
Purpose
Due to the high perforation rate of cervical pedicle screw placement, we have designed four different types of rapid prototyping navigation templates to enhance the accuracy of cervical pedicle screw placement.
Methods
Fifteen human cadaveric cervical spines from C2 to C7 were randomly divided into five groups, with three specimens in ea...
Context in source publication
Context 1
... the Group 1, the two-level RPNT was attached to C2-C3, C4-C5, and C6-C7, respectively. The average operation time was recorded during the surgery, from the time the surgeon began to place the RPNT on the posterior bony surface to the time the four screws were placed into every adjacent two-level vertebrae ( Figure 3). ...
Similar publications
3D-navigated pedicle screw placement is increasingly performed as the accuracy has been shown to be considerably higher compared to fluoroscopy-guidance. While different imaging and navigation devices can be used, there are few studies comparing these under similar conditions. Thus, the objective of this study was to compare the accuracy of two com...
Background
To evaluate reliability, practicability and precision of a novel intraoperative computed tomography(iCT)-based (Airo mobile CT scanner, Brainlab, Munich, Germany) navigated procedure to minimally-invasive positioning of cervical pedicle screws.
Methods
Ten consecutive patients that suffered from a cervical traumatic instability needing p...
Citations
... Alternatively, a guidance system such as O-arm-based three-dimensional (3D) navigation, 3D model, navigation templates, Doppler donography, robotic guidance system [7][8][9][10][11][12], or augmented reality-based navigation [13,14] is needed to prevent placement failure. The use of these resources is limited because of their high cost and steep associated learning curve however, and they cannot be widely applied in all kinds of hospitals [15,16]. ...
Background
Precise pedicle screw placement of the subaxial cervical spine is difficult. Not every hospital is equipped with a guidance system that can provide effective help. Computed tomography (CT) scanning is almost a routine preoperative examination for cervical spine surgery in all hospitals. Appropriate measurement and analysis of the CT images could assist optimal cervical pedicle screw placement. The purpose of this study is to propose a new and universal method using computed tomography (CT) morphological parameters analysis to assist optimal cervical pedicle screw placement from C3 to C7.
Methods
A localization system with six parameters was designed based on preoperative CT reconstruction to guide subaxial cervical spine pedicle screw placement. The six parameters were distance from the starting point to the midline [D1], distance from the starting point to the lower edge of the inferior articular process [D2], transverse section angle [TSA], sagittal section angle [SSA], pedicle width [PW], and pedicle height [PH]. The six parameters were analyzed in 53 participants.
Results
Combining D1 and D2 could localize the entrance of the pedicle screw, and we concluded that D1 and TSA and D2 and SSA could be a new standard for determination of the transverse and sagittal orientation of the pedicle screw. The six parameters were closely related to the patient’s gender, height, and weight. PH and PW were linearly correlated and could guide selection of the appropriate pedicle screw. SSA was an independent parameter of the relevant vertebral body, and changes in SSA had nothing to do with the curvature or posture of the cervical spine.
Conclusions
Understanding and applying the six-parameter localization system are essential for achieving accurate and optimal pedicle screw placement in subaxial cervical spine, regardless of cervical sagittal alignment.
... Alternatively, a guidance system such as O-arm-based three-dimensional (3D) navigation, 3D model, navigation templates, Doppler donography, robotic guidance system, [7][8][9][10][11][12] or augmented reality-based navigation [13 14] is needed to prevent placement failure. The use of these resources is limited because of their high cost and steep associated learning curve however, and they cannot be widely applied in all kinds of hospitals. ...
Background
Precise pedicle screw placement of the subaxial cervical spine is difficult. Not every hospital is equipped with a guidance system that can provide effective help. Computed tomography (CT) scanning is almost a routine preoperative examination for cervical spine surgery in all hospitals. Appropriate measurement and analysis of the CT images could assist optimal cervical pedicle screw placement. The purpose of this study is to propose a new and universal method using computed tomography (CT) morphological parameters analysis to assist optimal cervical pedicle screw placement from C3 to C7.
Methods
A localization system with six parameters was designed based on preoperative CT reconstruction to guide subaxial cervical spine pedicle screw placement. The six parameters were distance from the starting point to the midline [D1], distance from the starting point to the lower edge of the inferior articular process [D2], transverse section angle [TSA], sagittal section angle [SSA], pedicle width [PW], and pedicle height [PH]. The six parameters were analyzed in 53 participants.
Results
Combining D1 and D2 could localize the entrance of the pedicle screw, and we concluded that D1 and TSA and D2 and SSA could be a new standard for determination of the transverse and sagittal orientation of the pedicle screw. The six parameters were closely related to the patient’s gender, height, and weight. PH and PW were linearly correlated and could guide selection of the appropriate pedicle screw. SSA was an independent parameter of the relevant vertebral body, and changes in SSA had nothing to do with the curvature or posture of the cervical spine.
Conclusions
Understanding and applying the six-parameter localization system are essential for achieving accurate and optimal pedicle screw placement in subaxial cervical spine, regardless of cervical sagittal alignment.
Objective The aim of this study was to compare the accuracy of pedicle screw placement at the canine lumbosacral junction using a novel unilateral three-dimensional printed patient-specific guide (3D-PSG) versus a freehand drilling technique. Additionally, accuracy of screw placement between a novice and an experienced surgeon was determined.
Study Design Preoperative computed tomography images from 20 lumbosacral cadaveric specimens were used to design a novel unilateral 3D-PSG for the L7 and sacral vertebrae which was printed in acryl-nitrile butadiene styrene plastic. A novice and an expert surgeon each placed 3.5mm cortical screws in 10 cadavers; on the left using the unilateral 3D-PSG and by the freehand (anatomic landmark) technique on the right.
Results Sixty screws were placed using the unilateral 3D-PSG and 60 using the freehand technique. There was no statistical difference in accuracy for the comparison between methods performed by the expert (p = 0.679) and novice (p = 0.761) surgeon, nor between an expert and novice surgeon overall (p = 0.923). Unexpectedly, the use of a unilateral 3D-PSG increased variability for the expert surgeon in our study (p = 0.0314).
Conclusion Using a novel unilateral 3D-PSG did not improve the accuracy of screw placement for lumbosacral stabilization by a novice surgeon compared with an expert surgeon in lumbar spine surgery. This may reflect a suboptimal PSG design.
