O-arm navigation for sacroiliac screw placement in the treatment for posterior pelvic ring injury

Background. A large number of pelvic injuries are seriously unstable, with mortality rates reaching 19%. Approximately 60% of pelvic injuries are related to the posterior pelvic ring. However, the selection of a fixation method for a posterior pelvic ring injury remains a challenging problem for orthopedic surgeons. The aim of the present study is to investigate the biomechanical performance of five different fixation approaches for posterior pelvic ring injury and thus provide guidance on the choice of treatment approach in a clinical setting. Methods. A finite element (FE) model, including the L3-L5 lumbar vertebrae, sacrum, and full pelvis, was created from CT images of a healthy adult. Tile B and Tile C types of pelvic fractures were created in the model. Five different fixation methods for fixing the posterior ring injury (PRI) were simulated: TA1 (conservative treatment), TA2 (S1 screw fixation), TA3 (S1 + S2 screw fixation), TA4 (plate fixation), and TA5 (modified triangular osteosynthesis). Based on the fixation status (fixed or nonfixed) of the anterior ring and the fixation method for PRI, 20 different FE models were created. An upright standing loading scenario was simulated, and the resultant displacements at the sacroiliac joint were compared between different models. Results. When TA5 was applied, the resultant displacements at the sacroiliac joint were the smallest (1.5 mm, 1.6 mm, 1.6 mm, and 1.7 mm) for all the injury cases. The displacements induced by TA3 and TA2 were similar to those induced by TA5. TA4 led to larger displacements at the sacroiliac joint (2.3 mm, 2.4 mm, 4.8 mm, and 4.9 mm), and TA1 was the worst case (3.1 mm, 3.2 mm, 6.3 mm, and 6.5 mm). Conclusions. The best internal fixation method for PRI is the triangular osteosynthesis approach (TA5), followed by S1 + S2 screw fixation (TA3), S1 screw fixation (TA2), and plate fixation (TA4).

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Preoperative CT Simulation of Iliosacral Screws for Treating Unstable Posterior Pelvic Ring Injury

10.21203/rs.3.rs-1058330/v1 ◽

2021 ◽

Author(s):

Peishuai Zhao ◽

Xiaopan Wang ◽

Xiaotian Chen ◽

Jianzhong Guan ◽

Min Wu

Keyword(s):

Radiation Exposure ◽

Exposure Time ◽

Pelvic Ring ◽

Pelvic Ring Injury ◽

Posterior Pelvic Ring ◽

Iliosacral Screws ◽

Preoperative Ct ◽

Ct Simulation ◽

Posterior Pelvic Ring Injury

Abstract BackgroundPercutaneous iliosacral screw placement is an important surgical method for the treatment of pelvic unstable fractures, but either intraoperative X-ray screws or navigational screws may be misplaced. This study aimed to demonstrate a safe, effective, and rapid medthod for placing iliosacral screws for the treatment of unstable posterior pelvic ring injury according to preoperative computed tomography (CT) planning using simulated screws. MethodsAfter preoperative CT simulation of iliosacral screws planning screw insertion point and trajectory, intraoperative percutaneous iliosacral screws were used to treat unstable pelvic posterior ring injury.The mechanism of injury, Tile classification, number of screw implants, operative time of each screw implantation, radiation exposure time of each screw implantation screw position, complications, and postoperative follow-up time were collected.Screw position grading was evaluated by Smith grading. ResultsA total of 24 screws were implanted in 21 patients (9 men and 12 women;mean age 41.3 years:range 14-71 years). Tile classification included:Tile B:15 patients;Tile C:6 patients. The mean placement time of each screw was 19.5 minutes (range 14-32min); Radiation exposure time: 0.6 min (range 0.5-0.9min); Two screws were inserted in 3 patients; One screw was inserted in 18 patients; According to Smith grading standard, grade0:20 cases; and Grade1:1 case; Mean postoperative follow-up time was 17.1months (range12-25 months); None of the patients showed nonunion. ConclusionsPreoperative CT simulation of iliosacral screws for placement planning, screw trajectory, and intraoperative placement of screws is a safe method that can be used to reduce surgical time, radiation exposure, and accurate screw placement.

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Two-Dimensional Visualization of the Three-Dimensional Planned Sacroiliac Screw Corridor with the Slice Fusion Method

Journal of Clinical Medicine ◽

10.3390/jcm10020184 ◽

2021 ◽

Vol 10 (2) ◽

pp. 184

Author(s):

Maximilian Kerschbaum ◽

Siegmund Lang ◽

Florian Baumann ◽

Volker Alt ◽

Michael Worlicek

Keyword(s):

Pelvic Ring ◽

Three Dimensional ◽

Fusion Method ◽

Two Dimensional ◽

Posterior Pelvic Ring ◽

Simple Method ◽

Sacroiliac Screw ◽

Screw Insertion ◽

Multiplanar Reconstructions ◽

Screw Position

Insertion of sacro-iliac (SI) screws for stabilization of the posterior pelvic ring without intraoperative navigation or three-dimensional imaging can be challenging. The aim of this study was to develop a simple method to visualize the ideal SI screw corridor, on lateral two-dimensional images, corresponding to the lateral fluoroscopic view, used intraoperatively while screw insertion, to prevent neurovascular injury. We used multiplanar reconstructions of pre- and postoperative computed tomography scans (CT) to determine the position of the SI corridor. Then, we processed the dataset into a lateral two-dimensional slice fusion image (SFI) matching head and tip of the screw. Comparison of the preoperative SFI planning and the screw position in the postoperative SFI showed reproducible results. In conclusion, the slice fusion method is a simple technique for translation of three-dimensional planned SI screw positioning into a two-dimensional strict lateral fluoroscopic-like view.

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Tape suture for stabilization of incomplete posterior pelvic ring fractures—biomechanical analysis of a new minimally invasive treatment for incomplete lateral compression pelvic ring fractures

Journal of Orthopaedic Surgery and Research ◽

10.1186/s13018-019-1509-y ◽

2019 ◽

Vol 14 (1) ◽

Cited By ~ 3

Author(s):

Christopher Alexander Becker ◽

Adrian Cavalcanti Kussmaul ◽

Eduardo Manuel Suero ◽

Markus Regauer ◽

Matthias Woiczinski ◽

...

Keyword(s):

Pelvic Ring ◽

Tracking System ◽

Fracture Site ◽

Biomechanical Analysis ◽

Lateral Compression ◽

Posterior Pelvic Ring ◽

Sacroiliac Screw ◽

Minimal Invasiveness ◽

Compression Fractures ◽

Pelvic Ring Fractures

Abstract Background Incomplete lateral compression fractures (including AO Type B2.1) are among the most common pelvic ring injuries. Although the treatment of choice remains controversial, sacroiliac (SI) screws are commonly used for the operative treatment of incomplete lateral compression fractures of the pelvic ring. However, the disadvantages of SI screws include the risk of nerve root or blood vessel injury. Recently, tape sutures have been found useful as stabilizing material for the treatment of injuries of the syndesmosis, the rotator cuff and knee ligaments. In this current study, we aimed to test the biomechanical feasibility of tape sutures to stabilize the pelvis in the setting of AO Type B2.1 injury. Methods Six human cadaveric pelvises underwent cyclic loading to compare the biomechanical stability of different osteosynthesis methods in a B2.1 fracture model. The methods tested in this experiment were a FiberTape® suture and the currently established SI screw. A 3D ultrasound tracking system was used to measure fracture fragment motion. Linear regression was used to model displacement and stiffness at the posterior and anterior pelvic ring. Results At the posterior fracture site, the FiberTape® demonstrated similar displacement (2.2 ± 0.8 mm) and stiffness (52.2 ± 18.0 N/mm) compared to the sacroiliac screw (displacement 2.1 ± 0.6 mm, P > 0.999; stiffness 50.8 ± 13.0 N/mm, P > 0.999). Considering the anterior fracture site, the FiberTape® again demonstrated similar displacement (3.8 ± 1.3 mm) and stiffness (29.5 ± 9.0 N/mm) compared to the sacroiliac screw (displacement 2.9 ± 0.8 mm, P = 0.2196; stiffness 37.5 ± 11.5 N/mm, P = 0.0711). Conclusion The newly presented osteosynthesis, the FiberTape®, shows promising results for the stabilization of the posterior pelvic ring in AO Type B2.1 lateral compression fractures compared to a sacroiliac screw osteosynthesis based on its minimal-invasiveness and the statistically similar biomechanical properties.

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