Posterior pelvic ring fractures: Intraoperative 3D-CT guided navigation for accurate positioning of sacro-iliac screws

Fluoroscopic images of the sacroiliac joint alone are unable to identify simulated flexion or extension malreduction of the anterior pelvic ring in AO/OTA 61-B2.3 pelvic injuries

PURPOSE

Reduction of AO/OTA 61-B2.3 (APC2) pelvic fractures is challenging in the setting of anterior ring comminution. The anterior ring is visually much simpler to evaluate for flexion or extension hemipelvis deformity than the posterior ring, except in the setting of comminution, necessitating some other visual reference to judge hemipelvis reduction. We sought to test whether pelvic inlet and outlet fluoroscopy of the contours of the sacroiliac joint could be used in isolation to judge hemipelvis flexion or extension.

METHODS

Symphyseal and anterior SIJ ligaments were cut (6 cadaveric pelvis). The symphysis was held malreduced to produce one centimeter flexion and extension deformity: 1 cm was selected to mimic a maximum clinical scenario. The SIJ was assessed using inlet and outlet fluoroscopy. The scaled width of the SIJ was assessed at the joint apertures and midjoint on both inlet and outlet views. Joint widths in flexion and extension were compared against joint widths measured on the reduced SIJ using paired t-tests.

RESULTS

There was no statistical difference in the superior (p = 0.227, 0.675), middle (p = 0.203, 0.693), and inferior (p = 0.232, 0.961) SIJ widths between hemipelvis flexion or extension models against reduced SIJ on outlet views. There was no statistical difference in the anterior (p = 0.731, 0.662), middle (p = 0.257, 0.655), and posterior (p = 0.657, 0.363) SIJ widths between flexion or extension models against reduced SIJ on inlet views.

CONCLUSION

Inspection of SIJ width on inlet and outlet fluoroscopy cannot detect up to one centimeter of hemipelvis flexion or extension malreduction in the setting of AO/OTA 61-B2.3 (APC2) pelvic fractures with complex anterior injuries.

3D-navigation for SI screw fixation - How does it affect radiation exposure for patients and medical personnel?

BACKGROUND

3D-navigation for percutaneous sacroiliac (SI) screw fixation is becoming increasingly common and several studies report great advantages of this technology. However, there is still limited clinical evidence on the efficacy regarding radiation exposure for patient and personnel.

METHODS

This is a retrospective, single-center cohort study. All patients who underwent percutaneous sacroiliac screw fixation for an injury of the posterior pelvic ring from 2014 to 2021 were screened. Inclusion criteria were: conclusive radiation dosage reports, signed informed consent, a twelve month follow up and a complete data set. Patients were stratified in two groups (3D-navigation (Group 3D-N) vs. control (Group F)) based on the imaging modality used. Primary outcomes were radiation exposure for patient and personnel. Secondary outcomes were reoperations, complications, and intraoperative precision.

RESULTS

Of 392 patients screened, 174 patients (3D-N: n = 50, F: n = 124) could be included for final analysis. We noted a significant reduction of the dose corresponding to potential radiation exposure for medical personnel (-15.3 mGy, 95 %CI: -2.1 to -28.5, p = 0.0232), but also a significant increase of the dose quantifying radiation exposure for patients (+77.0 mGy, 95 %CI: +53.3 to +100.6, p < 0.0001), when using navigation. In addition, the rate of radiographic malplacement was significantly reduced (F: 11.3% vs. 3D-N: 0 %, p = 0.0113) despite a substantial increase in transsacral screw placement (F: 19.4% vs. 3D-N: 76 %).

CONCLUSION

Our data clearly suggests that the use of 3D-navigation for percutaneous SI screw fixation decreases radiation exposure for medical personnel, while increasing radiation exposure for patients. Furthermore, intraoperative precision is improved, even in more challenging operations.

The Role of MRI and CT Scan in Classification and Management of Pelvic Fractures: A Systematic Review

The mortality risk for individuals with pelvic fractures ranges from 10% to 50%, depending on the severity of the bleeding and the presence of concurrent brain, thorax, and abdomen injuries. This systematic review aims to comprehensively investigate the role of MRI and CT in diagnosing and managing pelvic fractures. PubMed, SCOPUS, Web of Science, and Science Direct were systematically searched for relevant literature. The keywords "Pelvic fractures," "Diagnosis," "Computed tomography," "CT," "Magnetic resonance imaging," and "MRI" were converted into PubMed Mesh terms and used to find the relevant studies. Rayyan Qatar Computing Research Institute (QCRI) was employed throughout this comprehensive process. The systematic review included publications with full English text, available free articles, and human trials among adults. This review included 12 studies with 1,798 patients, and 935 (52%) of them were females. Two articles were prospective, and 10 articles were retrospective. In conclusion, the diagnosis and management of pelvic fractures require a tailored approach based on patient characteristics, injury mechanisms, and hemodynamic status. Because MRI detects a high number of concealed sacral fractures, it provides greater sensitivity and diagnostic validity in identifying acute pelvic fractures. Moreover, MRI is effective in diagnosing occult pelvic fractures and detecting soft tissue anomalies. However, MRI is unlikely to replace CT as the gold standard in the initial diagnosis of pelvic fractures; CT may also be preferable to MRI due to shorter emergency department (ED) time and the significant proportion of elderly patients who are contraindicated to MRI. Additionally, CT scanning aids in determining the need for emergent angiographic embolization and facilitates surgical planning.

Sacral Fractures: A Review

At the cornerstone of the pelvis and spine, the sacrum may be fractured in patients of all ages. Sacral fractures range from high-energy injuries, with mortality rates of up to 18%, to low-energy insufficiency fractures. The intricate geometry of the sacrum, the breadth of morphotypes, and the presence of congenital anomalies all can complicate the treatment of these fractures. Agreement on the surgical indications for these injuries is limited. This narrative review aims to update orthopedic surgeons on the clinical evaluation and the non-surgical and surgical management of these fractures.

Navigated Percutaneous Sacroiliac Screw Fixation in Unstable Pelvic Ring Fracture

Since the late 1990s, navigation systems have been widely used in a variety of orthopaedic surgical procedures, with the majority of these procedures being complex arthroplasty surgeries and the correction of spinal abnormalities. Navigation systems are, however, infrequently used in trauma cases, especially in unstable pelvic ring fractures. The conventional method of percutaneous sacroiliac screw fixation typically used fluoroscopic image intensifiers to fix unstable pelvic ring fractures. We will examine how navigation systems can be used in trauma situations, particularly those involving unstable posterior pelvic ring fractures and focus on the advantages and disadvantages that we experienced during management.

[TiRobot-assisted surgery by O-arm navigation system for percutaneous minimally invasive treatment of posterior pelvic ring injury]

Objective

To evaluate the effectiveness of TiRobot-assisted surgery by O-arm navigation system for percutaneous minimally invasive treatment of posterior pelvic ring injury.

Methods

The clinical data of 76 patients with posterior pelvic ring injury between January 2016 and June 2021 were retrospectively analyzed. Among them, 45 cases were treated with minimally invasive percutaneous sacroiliac screw fixation assisted by TiRobot and O-arm navigation system (study group), 31 cases were treated with minimally invasive percutaneous sacroiliac screw fixation under the guidance of C-arm X-ray machine (control group). There was no significant difference in gender, age, cause of injury, Tile classification, time from injury to operation between the two groups ( P>0.05). The operation time, intraoperative blood loss, the times of nail track adjustment, and intraoperative fluoroscopy times were recorded. The quality of fracture reduction was evaluated by Matta score. At last follow-up, Majeed score was used to evaluate the recovery of pelvic function.

Results

A total of 72 screws were implanted in the study group, with a median of 1 (1, 2) screws per patient. In the control group, 47 screws were implanted, with a median of 1 (1, 2) screws per patient. There was no significant difference in the number of screws between the two groups ( Z=-0.392, P=0.695). The operation time, intraoperative blood loss, times of nail track adjustment, and intraoperative fluoroscopy times in the study group were significantly less than those in the control group ( P<0.05). All patients were followed up 6-24 months (mean, 14 months). No serious complications was found after operation and during follow-up. Matta score was used to evaluate the quality of fracture reduction at 1 week after operation, and there was no significant difference between the two groups ( Z=-1.135, P=0.256). At last follow-up, there was no significant difference of Majeed score between the two groups ( Z=-1.279, P=0.201).

Conclusion

TiRobot-assisted surgery by O-arm navigation system is a reliable surgical method for the treatment of posterior pelvic ring injury, which can reduce the operation time and fluoroscopy times when compared with the traditional operation under the guidance of C-arm X-ray machine. The safety, accuracy, and efficiency of the operation were improved.

Comparison of fluoroscopy and fluoroscopy-based 2D computer navigation for iliosacral screw placement: a retrospective study

PURPOSE

Treatment of pelvic fractures is often complicated. Here, we intended to evaluate the intraoperative benefits of using 2D computer navigation when compared with traditional fluoroscopy on X-ray burden, surgical time and screw placement accuracy.

METHODS

In this study, we retrospectively evaluated the records of 25 patients who underwent osteosynthesis of a posterior pelvic fracture using fluoroscopy at the University Hospital Ostrava, Czech Republic between 2011 and 2019, and 32 patients from the same department and period in whom 2D computer navigation was used.

RESULTS

Intraoperative X-ray burden was significantly lower in the group with 2D computer navigation (median 650 vs 1024 cGy/cm²), as was the duration of the surgery (41 vs 45 min). This was most obvious where two screws were inserted (X-ray dose of 994 vs 1847 cGy/cm² and 48 vs 70 min, respectively). Correction of the path for wire placement after the original drilling was necessary in 2 patients (6%) from the 2D computer navigation group and 15 patients from the fluoroscopy group (60%). Still, no malposition of the screws nor dislocation of the posterior pelvic segment after 12 months was observed in any patient of either group; of complications, only three superficial infections in the 2D navigation group and 2 in the fluoroscopy group were observed.

CONCLUSION

2D computer navigation is a safe and accurate method for placement of screws during posterior pelvic fracture osteosynthesis, associated with lower intraoperative radiation burden and shorter surgical times compared to standard fluoroscopy, especially if two screws are inserted.

Screw misplacement in percutaneous posterior pelvic iliosacral screwing with and without navigation: A prospective clinical study of 174 screws in 127 patients

BACKGROUND

Recent studies of iliosacral screw fixation performed using intraoperative navigation systems have shown promising results. The Surgivisio Platform is a new-generation three-dimensional intraoperative navigation tool that has been used at our institution for 2years. The aim of this prospective study was to assess the contribution of navigation in terms of iliosacral screw positioning accuracy and of radiation exposure, by comparing outcomes with vs. without navigation.

HYPOTHESIS

Navigation allows more accurate percutaneous iliosacral screw positioning regardless of the type of screw fixation (with sacral dysmorphism and/or cemented screw fixation and/or multiple screw fixation).

MATERIALS AND METHODS

Between January 2018 and December 2019, consecutive patients who underwent percutaneous iliosacral screw fixation of pelvic ring fractures without vertical instability were included in this single-centre prospective study. Screw position accuracy was evaluated by postoperative high-resolution computed tomography (HRCT). Operative time, radiation dose, and complications were recorded.

RESULTS

We included 127 patients with 174 iliosacral screws, of which 129 were positioned under fluoroscopic guidance and 45 using navigation. According to the modified Gras classification, 7% (12/174) of the screws were incorrectly positioned and 2% (4/174) required repositioning. The frequency of screw malposition was not significantly different between the fluoroscopy and navigation groups (8.5%, 11/129 vs. 2.2%, 1/45, respectively; p=0.19). However, screw position in dysmorphic sacra was significantly better with navigation (p=0.04), whereas no significant difference in final screw position was found for cemented or multiple screw implantations. In the navigation group, the operative time was significantly longer (28.2min vs. 21.6min, p=0.003), and the mean dose-area product significantly greater (6.6Gy·cm² vs. 4.9Gy·cm², p=0.02). The complication rates were not different between the two groups.

CONCLUSION

In patients who have pelvic ring fractures without vertical instability, navigation of percutaneous iliosacral screw placement using the Surgivisio Platform improves screw positioning in dysmorphic sacra, at the cost of a longer operative time and greater radiation exposure of the patient.

LEVEL OF EVIDENCE

II, prospective study.

Clinical research-When it matters

Clinical research runs through the entire progress of the science and technology which has been currently and previously applied to the medical field. It has gradually developed into a standardized procedure and played an important role in understanding the etiology and characteristics of diseases. Clinical researchs assess the effectiveness and safety of new/improved diagnostic or therapeutic technologies, implants, instruments, or drug applications, to discover new data and improve potential deficiencies in previous medical knowledge.

The combination of intraoperative CT navigation and C-arm fluoroscopy for INFIX and percutaneous TITS screw placement in the treatment of pelvic ring injury: technical note

Background

The subcutaneous screw rod system, commonly known as the internal pelvic fixator (INFIX), is useful in managing unstable pelvic ring fractures. Conventional INFIX and transiliac–transsacral (TITS) screw techniques are performed using C-arm fluoroscopy. There have been problems with medical exposure and screw insertion accuracy with these techniques. This work describes new INFIX and TITS techniques using intraoperative computed tomography (CT) navigation and C-arm fluoroscopy for pelvic ring fracture.

Methods

A typical case is presented in this study. An 86-year-old woman suffered from an unstable pelvic ring fracture due to a fall from a height. INFIX and TITS screw fixation with intraoperative CT navigation were selected to optimize surgical invasiveness and proper implant placement.

Results

The patient was placed in a supine position on a Jackson table. An intraoperative CT navigation was imaged, and screws were inserted under the navigation. Postoperative X-rays and CT confirmed that the screw was inserted correctly. This technique was less invasive to the patient and had little radiation exposure to the surgeon. Rehabilitation of walking practice was started early after the surgery, and she was able to walk with the assistance of a walker by the time of transfer.

Conclusions

The technique employed in our case study has the cumulative advantages of safety, accuracy, and reduced radiation exposure, together with the inherent advantages of functional outcomes of previously reported INFIX and TITS screw techniques. Further experience with this approach will refine this technique to overcome its limitations and facilitate its wider use.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-02920-0.

Clinical Analysis of Single and Double Sacroiliac Screws in the Treatment of Tile C1 Pelvic Fracture

We investigated the difference between fixation of single and double sacroiliac screws in the treatment of Tile C1 pelvic fractures. The data of 54 patients with Tile C1 pelvic fractures who were admitted to the trauma center of the Red Society Hospital Affiliated to Xi’an Jiaotong University between August 2016 and August 2020 were retrospectively analyzed. All patients with posterior pelvic ring injuries underwent fixation with sacroiliac screws assisted by a percutaneous robotic navigation system. The operative time, amount of intraoperative blood loss, and postoperative follow-up time between the two groups (single sacroiliac and double sacroiliac screw groups) were compared. The Matta and Majeed scores at the last follow-up were compared between the groups to evaluate fracture reduction and functional recovery. Forty-nine patients were followed up for 17.2 (±4.5) months and 16.2 (±3.4) months in the single and double sacroiliac screw groups, respectively. All patients had excellent fracture reduction immediately after surgery, according to the Matta score. All fractures healed without complications. There was no statistically significant difference in preoperative general information, amount intraoperative blood loss, intraoperative anterior ring fixation method, and postoperative follow-up time between the two groups ( $P>0.05$ ). The operative time of the single sacroiliac screw group was shorter than that of the double sacroiliac screw group ( $P<0.05$ ). At the last follow-up, the Matta score of the double sacroiliac screw group was significantly better than that of the single sacroiliac screw group ( $P<0.05$ ), and there was no statistically significant difference in the Majeed functional scores ( $P>0.05$ ). For Tile C1 pelvic fractures, double sacroiliac screw fixation of posterior ring injuries can provide a more stable treatment with no statistically significant difference in functional recovery.

Accuracy of screw stabilization of the dorsal pelvic ring using a hybrid operating room: 5 Year experience in a level 1 trauma center

INTRODUCTION

Accuracy for screw placement in the dorsal pelvic ring can be enhanced using intraoperative 3D navigation. Advances in intraoperative imaging lead to benefits for pelvic surgery. New c-arms are equipped with flat panel detectors, which have a larger detector and assure higher image quality with accompanying dose reduction. A hybrid OR is defined by a fixed imaging system in an operating room providing the benefit of the surgical environment in combination with advanced intraoperative imaging. Aim of our investigation was to analyze the accuracy of navigated sacroiliac (SI) and transsacral transiliac (TSTI) screws in the dorsal pelvic ring, which were implanted with a hybrid OR in the first five years of use.

MATERIAL AND METHODS

All percutaneous SI or TSTI screws implanted in the hybrid OR using intraoperative navigation in the first 5 years of utilization (between June 2012 to June 2017) were included. Intraoperative 3D-scans and postoperative computed tomography were examined for screw perforation.

RESULTS

210 SI and TSTI screws were implanted in 187 patients using intraoperative navigation in the hybrid-OR. 90.6 % of SI screws showed no cortical perforation. 6,3 % had a grade 1, 2.4 % a grade 2 and 0.8 % a grade 3 perforation. In 80.7 % of TSTI screws no perforation and in 13.3 % a grade 1 perforation was detected. 3.6 % showed a grade 2 and 2.4 % a grade 3 perforation. No significant difference between both screw types regarding the grade of cortical perforation could be seen. No significant relation between perforation rate and year of operation could be detected.

CONCLUSION

Intraoperative navigation in a hybrid OR ensures a high accuracy for SI screws. Due to the large field of view and high image quality TSTI screws can be safely implanted in S1 and S2. Utilization of a hybrid-OR is accompanied with a steep learning curve.

Does 3D-Assisted Operative Treatment of Pelvic Ring Injuries Improve Patient Outcome?-A Systematic Review of the Literature

Background: There has been an exponential growth in the use of advanced technologies for three-dimensional (3D) virtual pre- and intra-operative planning of pelvic ring injury surgery but potential benefits remain unclear. The purpose of this study was to evaluate differences in intra- and post-operative results between 3D and conventional (2D) surgery. Methods: A systematic review was performed including published studies between 1 January 2010 and 22 May 2020 on all available 3D techniques in pelvic ring injury surgery. Studies were assessed for their methodological quality according to the Modified McMaster Critical Review form. Differences in operation time, blood loss, fluoroscopy time, screw malposition rate, fracture reduction and functional outcome between 3D-assisted and conventional (2D) pelvic injury treatment were evaluated and a best-evidence synthesis was performed. Results: Eighteen studies fulfilled the inclusion criteria, evaluating a total of 988 patients. Overall quality was moderate. Regarding intra-operative results of 3D-assisted versus conventional surgery: The weighted mean operation time per screw was 43 min versus 52 min; for overall operation time 126 min versus 141 min; blood loss 275 ± 197 mL versus 549 ± 404 mL; fluoroscopy time 74 s versus 125 s and fluoroscopy frequency 29 ± 4 versus 63 ± 3. In terms of post-operative outcomes of 3D-assisted versus conventional surgery: weighted mean screw malposition rate was 8% versus 18%; quality of fracture reduction measured by the total excellent/good rate by Matta was 86% versus 82% and Majeed excellent/good rate 88% versus 83%. Conclusion: The 3D-assisted surgery technologies seem to have a positive effect on operation time, blood loss, fluoroscopy dose, time and frequency as well as accuracy of screw placement. No improvement in clinical outcome in terms of fracture reduction and functional outcome has been established so far. Due to a wide range of methodological quality and heterogeneity between the included studies, results should be interpreted with caution.

Current Minimally Invasive Surgical Concepts for Sacral Insufficiency Fractures

An increasing incidence of sacral insufficiency fractures in geriatric patients has been documented, representing a major challenge to our healthcare system. Determining the accurate diagnosis requires the use of sectional imaging, including computed tomography and magnetic resonance imaging. Initially, non-surgical treatment is indicated for the majority of patients. If non-surgical treatment fails, several minimally invasive therapeutic strategies can be used, which have shown promising results in small case series. These approaches are sacroplasty, percutaneous iliosacral screw fixation (S1 with or without S2), trans-sacral screw fixation or implantation of a trans-sacral bar, transiliac internal fixator stabilisation, and spinopelvic stabilisation. These surgical strategies and their indications are reported in detail. Generally, treatment-related decision making depends on the clinical presentation, fracture morphology, and attending surgeon's experience.

Robot-Aided Minimally Invasive Lumbopelvic Fixation in Treatment of Traumatic Spinopelvic Dissociation

Objective

To investigate the surgical strategy, safety, and efficacy of close reduction and robot‐aided minimally invasive lumbopelvic fixation in treatment of traumatic spinopelvic dissociation.

Methods

Data of 32 patients (21 males and 11 females) with traumatic spinopelvic dissociation treated by lumbopelvic fixation with robot‐aided minimally invasive technique or conventional open procedure in our institution from March 2010 to April 2019 were retrospectively analyzed, and divided into robot group and control group. Intraoperative blood loss, surgical time, fluoroscopy frequency, total drilling times, infection rate, hospitalization time, and sacral fracture healing time were reviewed. Radiographs and computed tomography (CT) scans were totally acquired to evaluate the reduction quality, residual fracture displacement, and Gras classification on screws insertion after surgery. According to the Majeed scoring system, functional outcome was assessed for each patient at the final follow‐up.

Results

There were 12 patients in the robot group and 20 patients in the control group with no significant difference about the demographic data. The average surgical time was 148.3 ± 40.5 min with intraoperative blood loss of 142.5±36.7 mL in the robot group and 185.0 ± 47.8 min with 612.5 ± 182.7 mL in the control group (P = 0.034, P = 0.000). The robot group had a shorter mean hospitalization time at 19.9 ± 7.0 days compared to the control group with 28.6 ± 5.4 days (P = 0.010). The fluoroscopy frequency was 35.4 ± 3.0 in the robot group and 45.5 ± 3.6 in the control group (P = 0.000) and total drilling times were 7.1 ± 1.1 and 9.6 ± 1.3 (P = 0.000), respectively. The infection rate was 0% (0/12) in the robot group and 15% (3/20) in the control group (P = 0.159). According to the Gras classification on screw positioning, there were 11 cases in Grade I and 1 case in Grade II in the robot group, and 14 cases in Grade I and 6 cases in Grade II in the control group. All the patients were followed up consecutively for at least 12 months, with an average follow‐up period of 17.1 ± 3.6 months. All sacral fractures healed with an average time of 3.8 ± 0.6 months in the robot group and 4.7 ± 0.7 months in the control group (P = 0.000). According to Majeed functional assessment investigation, the mean score of the patients was 87.2 ± 4.0 in the robot group and 83.1 ± 4.5 in the control group (P = 0.015).

Conclusions

Robot‐aided minimally invasive lumbopelvic fixation for traumatic spinopelvic dissociation is a safe and feasible option with advantages of less intraoperative blood loss, less radiation damage, less hospitalization time, and better functional outcome.

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

PURPOSE

This study aims to investigate the application value of O-arm navigation system in sacroiliac screw placement for the treatment of unstable pelvic ring injury.

METHODS

A total of 40 patients (mean age = 30.75 ± 14.99 years, 25 males, 15 females) were included. From January 2016 to July 2018, 40 patients with posterior pelvic ring injury treated in our hospital were included. Of them, 19 patients underwent O-arm navigation for screw placement (O-arm group) while the other 21 received C-arm fluoroscopy guidance (C-arm group) for sacroiliac screw placement. Intraoperative outcomes and the outcome of screw placement were compared between groups. The quality of radiological images was assessed by Matta's radiological outcome grade. The outcome of complex pelvic fracture treatment was evaluated by Majeed Functional score.

RESULTS

All demographic and clinical characteristics were comparable between the two groups. Compared with the C-arm groups, the O-arm group had a shorter surgery time (33.19 ± 3.14 vs. 48.35 ± 4.38 min, P < 0.001), a higher overall good outcome "excellent + good" rate of screw placement (95.45% vs. 73.91%, P < 0.05), and a significantly higher Majeed Functional score better outcome of complex pelvic fracture treatment at 1 and 3 months postoperation (both P < 0.05).

CONCLUSION

Our results demonstrated that O-arm navigation system is feasible and safe for the treatment of posterior pelvic ring injury and can effectively improve the accuracy and safety of sacroiliac screw placement, shorten the operation time, and help rapid postoperative functional recovery.

A useful intraoperative technique for transiliac-transsacral screws: a point-to-point coaxial guide apparatus

Background

The transiliac-transsacral screw placement is a clinical challenge for surgeons. This study explored a point-to-point coaxial guide apparatus assisting the transiliac-transsacral screw insertion and aimed to investigate the feasibility and accuracy of the guide apparatus in the treatment of posterior ring unstable pelvic fracture compared with a free-hand technique.

Methods

A retrospective study was performed to evaluate patients treated with transiliac-transsacral screws assisted by the point-to-point coaxial guide apparatus or free-hand technique. The intraoperative data of operative time and radiation exposure times were recorded. Postoperative radiographs and CT scans were performed to scrutinize the accuracy of screws position. The quality of the postoperative fracture reduction was assessed according to Matta radiology criteria. The pelvic function was assessed according to the Majeed scoring criteria at 6 months postoperatively.

Results

From July 2017 to December 2019, a total of 38 patients were included in this study, 20 from the point-to-point guide apparatus group and 18 from the free-hand group. There were no significant differences between the two groups in gender, age, injury causes, pelvic fracture type, screws level, and follow-up time (P > 0.05). The average operative time of the guide apparatus group for each screw was significantly less than that in the free-hand group (25.8 ± 4.7 min vs 40.5 ± 5.1, P < 0.001). The radiation exposure times were significantly lower in the guide apparatus group than that in the free-hand group (24.4 ± 6.0 vs 51.6 ± 8.4, P < 0.001). The intraosseous and juxtacortical rate of screw placement (100%) higher than in the free-hand group (94.4%).

Conclusion

The point-to-point coaxial guide apparatus is feasible for assisting the transiliac-transsacral screw in the treatment of posterior unstable pelvic fractures. It has the advantages of simple operation, reasonable design and no need for expensive equipment, and provides an additional surgical strategy for the insertion of the transiliac-transsacral screw.

Volar Locking Plate Fixation for Distal Radius Fractures by Intraoperative Computed Tomographic–Guided Navigation

Purpose

Unstable distal radius intra-articular fractures require restoration of alignment. Exact fixation of intra-articular fragments is ideal. Here, we employed intraoperative computed tomography (CT) navigation to insert screws accurately in the intra-articular dorsal fragments during treatment with a volar locking plate for distal radius intra-articular fractures. The main purposes of this study were to evaluate the accuracy of this procedure and the postoperative stability of the articular fragments through CT findings, as well as to assess clinical outcomes.

Methods

This study included 26 patients with distal radius fractures, who were treated with a volar locking plate using intraoperative CT navigation with a minimum follow-up of 12 months. Mean patient age was 63 years and mean follow-up was 16 months. We examined the position of the inserted distal screws and articular displacement on preoperative, intraoperative, and post–bone union CT images. The 3 distal ulnar screw positions that influence the stability of the dorsoulnar articular fragment were evaluated. The Mayo wrist score and Disabilities of the Arm, Shoulder, and Hand score were also clinically evaluated.

Results

Computed tomography evaluation revealed that the distal locking screws were appropriately inserted at the subchondral position, with sufficient length to stabilize the dorsal fragments, and reduction and stability of the articular fragment were acceptable. At the final follow-up, mean Mayo wrist score was 90.8 and mean Disabilities of the Arm, Shoulder, and Hand score was 9.6.

Conclusions

Intraoperative CT navigation was successfully used for volar locking plate fixation of intra-articular distal radius fractures. Computed tomography evaluation revealed that the screws were precisely inserted for articular fragments and bone union was achieved, maintaining good intra-articular alignment. The findings demonstrate the accuracy of volar locking plate fixation assisted by intraoperative CT navigation and the good clinical outcomes of this procedure.

Type of study/level of evidence

Therapeutic IV.

Safety, Effect and Feasibility of Percutaneous SI-Screw with and without Augmentation-A 15-Year Retrospective Analysis on over 640 Screws

BACKGROUND

Minimally invasive sacroiliac-screw (SI-screw) fixation of the pelvis is used in energy trauma (Arbeitsgemeinschaft für Osteosynthesefragen (AO) classified) and fragility fractures (Fragility Fracture of the Pelvis (FFP) classified). However, available clinical data are based on small case series and biomechanical data seem to be contradictory.

METHODS

The present single center retrospective cohort study investigated percutaneous SI-screw fixation and augmentation over 15 years. Groups were compared concerning the general epidemiological data, mobilization, complication rates, duration of stay, and safety of SI-screw insertion. Multivariable analyses were performed using logistic regression.

RESULTS

Between 2005 and March 2020, 448 patients with 642 inserted SI-screws were identified. Iatrogenic neurological impairment was documented in 2.47% and correlated with screw misplacement. There was an increased complication risk in patients with AO type C over patients with AO type B and in FFP II over FFP III/IV patients. Cement-augmented FFP patients showed a 25% reduced stay in hospital and a reduced complication risk. Cement-associated complications were seen in 22% without correlation to neurologic impairment.

CONCLUSIONS

The present study confirms the safety and usability of percutaneous SI-screw fixation, despite specific risks. Cement augmentation seems to reduce the complication risk in FFP patients and shorten hospital stay for some reasons, without increased specific complications or correlated neurological impairment.

3D - Navigated percutaneous screw fixation of pelvic ring injuries - a pilot study

INTRODUCTION

Screw fixation of pelvic ring fractures is a common, but demanding procedure and navigation techniques were introduced to increase the precision of screw placement. The purpose of this case series is to demonstrate a lower screw malposition rate using percutaneous fixation of pelvic ring fractures and sacroiliac dislocations guided by navigation system based on 3D-fluoroscopic images compared to traditional imaging techniques and to evaluate the functional outcomes of this innovative procedure.

PATIENT AND METHODS

10 cases of disrupted pelvic ring lesions treated in our hospital from February 2018 to December 2018 were included for closed reduction and percutaneous screw fixation of using with O-Arm and the acquisition by the Navigator. Preoperative assessment was performed on the patients by means of X Ray imaging and CT scan. Routine CT was carried out on third postoperative day to evaluate screw placement. Measures of radiation exposure were extracted directly from reports provided by system. Quality of life was evaluated by SF 36-questionnaire 6 months after surgery.

RESULTS

12 iliosacral- and 2 ramus pubic-screws were inserted. In post-operative CT-scans the screw position was assessed and graded using the score described by Smith. No wound infection or iatrogenic neurovascular damage were observed. No re-operations were performed. The exposure to radiation is, for the patient, slightly greater than that resulting from the use of traditional fluoroscopic systems, while it is naught for the surgical team, which at the time of image acquisition is located outside the room.

DISCUSSION AND CONCLUSION

The execution of an intraoperative 3D-fluoroscopic scan can on its own suffice as a post-operative control examination since its accuracy is similar to that of the post-operative CT. The use of a navigated 3d fluoroscopy exposes the patient to an amount of radiation slightly greater than that of traditional fluoroscopy, but the dose is lower than a CT examination. For the operating team, exposure to radiation is naught. 3D-fluoroscopic navigation is a safe tool providing high accuracy of percutaneous screw placement for pelvic ring fractures. Finally, despite the small cohort of patients studied, the excellent results obtained regarding the patients' quality of life and the absence of complications allow us to look positively at the future of this technique, which needs further studies and improvement.

[Intelligent monitoring system assisted pelvic fracture closed reduction for treating one case with complex pelvic fracture]

Objective

To introduce the experience of intelligent monitoring system assisted pelvic fracture closed reduction to treat complex pelvic fracture in a minimally invasive method.

Methods

A 30-year-old male patient with complex pelvic fracture caused by a falling injury was treated in December 2019. The pelvic fracture was diagnosed by X-ray film and CT three-dimensional reconstruction. The AO/Orthopaedic Trauma Association (AO/OTA) classification was 61-C3.3 type (H-shaped sacrum fracture with pubic symphysis separation). At 48 hours after injury, the vital signs were stable, and the operation was performed. The pelvic fracture was reduced with the help of pelvic reduction frame and skeletal traction, the intelligent monitoring system, and fixed with the channel screws.

Results

The intraoperative blood loss was 50 mL, the operation time was 180 minutes, and the fluoroscopy time was 45 seconds. The incision healed well after operation. The X-ray film of pelvis was taken on the next day after operation, and the fracture reduction was evaluated as anatomical reduction according to Matta standard; CT three-dimensional reconstruction showed that the fixation screws were all located in the cortex of bone, without penetrating the cortex of bone.

Conclusion

The intelligent monitoring system assisted pelvic fracture closed reduction is reliable in the minimally invasive treatment of complex pelvic fractures, which can achieve good results and reduce intraoperative fluoroscopy.

Computer navigation-assisted minimally invasive percutaneous screw placement for pelvic fractures

Pelvic fractures are often caused by high-energy injuries and accompanied by hemodynamic instability. Traditional open surgery has a large amount of bleeding, which is not suitable for patients with acute pelvic fracture. Navigation-guided, percutaneous puncture-screw implantation has gradually become a preferred procedure due to its advantages, which include less trauma, faster recovery times, and less bleeding. However, due to the complexity of pelvic anatomy, doctors often encounter some problems when using navigation to treat pelvic fractures. This article reviews the indications, contraindications, surgical procedures, and related complications of this procedure for the treatment of sacral fractures, sacroiliac joint injuries, pelvic ring injuries, and acetabular fractures. We also analyze the causes of inaccurate screw placement. Percutaneous screw placement under navigational guidance has the advantages of high accuracy, low incidence of complications and small soft-tissue damage, minimal blood loss, short hospital stays, and quick recovery. There is no difference in the incidence of complications between surgeries performed by new doctors and experienced ones. However, computer navigation technology requires extensive training, and attention should be given to avoid complications such as screw misplacement, intestinal injury, and serious blood vessel and nerve injuries caused by navigational drift.

The usefulness of reformatting CT scanning plane to distinguish sacral dysmorphism and introducing the variable of elevated height for predicting the possibility of trans-sacral screw fixation

INTRODUCTION

Ilio-sacral screw fixation has been used for sacral fractures and sacroiliac joint dislocations. However, it is associated with significant complications including screw loosening with backing-out and loss of reduction. Trans-sacral screw fixation is indicated for rigid fixation in specific circumstances including bilateral posterior ring injuries, osteoporotic bone, or to supplement other types of posterior ring fixation.

HYPOTHESIS

The reformatting the CT scanning plane may distinguish sacral dysmorphism and predict the possibility of trans-sacral screw fixation by introducing the new indicator.

MATERIAL AND METHODS

The CT data of 112 adult cadavers (61 males and 51 females) were imported into Mimics® software and a 7.0 mm-sized trans-sacral screw was virtually placed in the ideal position of S₁. The osseous widths around screw in the axial images (AxW_S1) were measured. By reformatting the CT scanning plane parallel to the superior endplate of S₁, the AxWR_S1 was measured and the height of elevated segment in the upper sacrum (elevated height) was assessed as a new preoperative indicator.

RESULTS

Cortical violation around screw was detected in 26 models and was considered as sacral dysmorphism. The average AxW_S1 was measured as 13.70±2.76mm in the non-dysmorphism group, and 5.81±2.19mm in the dysmorphism group, with statistical difference (p<0.001). By reformatting the CT scanning plane, the average AxWR_S1 increased to 16.61±2.79mm in the non-dysmorphism group, and 8.04±2.62 in the dysmorphism group, and the difference was statistically significant (p<0.001). The elevated height was 3.29±4.19mm in the non-dysmorphism group, and 17.52±3.09mm in the dysmorphism group, and the differences were statistically significant (p<0.001). Based on the ROC curve analysis, the cut-off value of elevated height was 12.90mm (sensitivity 1.0 and specificity 1.0).

DISCUSSION

By reformatting the CT scanning plane, the osseous width around screw was widened, and the new preoperative indicator of elevated height could be introduced to predict the possibility of trans-sacral screw fixation into S₁. If the elevated height exceeded 13mm, the pelvis was assigned to sacral dysmorphism and thus, could not apply the trans-sacral screw fixation into S₁.

LEVEL OF EVIDENCE

III, controlled laboratory study.