Traumatic Sacral Fractures: Navigation Technique in Instrumented Stabilization

Innovation in Neurosurgery Special Section

Traumatic Sacral Fractures: Navigation Technique in Instrumented Stabilization Giorgio Santoro1, Piero Braidotti2, Fabrizio Gregori1, Antonio Santoro1, Maurizio Domenicucci1

BACKGROUND: Sacral fractures are a challenge regarding treatment and classification. Surgical techniques using spinal navigation systems can improve treatment, especially if used in collaboration among different specialists.

safety, reducing learning times and malpositioning. Multidisciplinary management allows us to achieve optimal results, especially when the sacral fracture is combined with spinal and pelvic lesions. The use of navigation systems could represent an important advancement.

METHODS: Between 2015 and 2017, we treated 25 consecutive cases of sacral fracture. Twelve patients (48%) underwent mechanical ventilation due to hypovolemic shock for severe thoracoabdominal trauma; bleeding was blocked with pelvic packing in 9 cases (36%) and transcatheter embolization in 2 cases (8%). External fixation was used in 7 cases (28%). In 20 cases (80%) spinal fractures were associated. All patients were operated on using spinal navigation by a team of neurosurgeons and orthopedic surgeons.

INTRODUCTION

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RESULTS: The mean time from first observation to surgery was 18 days (range 8e31). Surgical treatment consisted of iliosacral fixation in 19 cases (76%) and spinopelvic fixation in 6 cases (24%). The mean number of screws for spinopelvic fixation was 9.67 (range 6e17) with a mean operation time of 323.67 minutes (range 247e471); in iliosacral osteosynthesis the mean screw number was 1.37 (range 1e3) and mean surgical time was 78.93 minutes (range 61e130). Postoperative computed tomography showed the correct screw placement. Wound infection occurred in 2 cases (8%), managed with vacuum-assisted closure therapy; in 1 case (4%) a sacral screw was removed for decubitus.

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CONCLUSIONS: Navigation systems in instrumented spinopelvic and sacropelvic reconstruction provide greater

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Key words Classification - Fracture - Navigation - Pelvic - Sacral - Spinal - Traumatic -

Abbreviations and Acronyms AIS: American Spinal Injury Association (ASIA) Impairment Scale CT: Computed tomography IGS: Imaging guidance surgery

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solated sacral fractures are rare, while in 80% of the cases they occur in association with pelvic ring fractures or more rarely in association with thoracolumbar spine fractures or lumbar-sacral junction lesions.1,2 Due to their relative rarity and heterogeneity, they are often the subject of controversial classification and heterogeneous treatment.3 Surgical treatment of these lesions is performed by instrumented stabilization, limited to the pelvis or extended to the vertebral column.4-6 Open reduction and internal fixation of the sacropelvic complex is burdened by a considerable malposition rate due to complex regional anatomy and its difficult visualization by conventional intraoperative radiologic images.7-9 Furthermore, due to the important biomechanical forces discharging on the lumbosacropelvic complex, the complications rate such as pseudoarthrosis, screw pullout, implant rupture, and secondary sacral fractures remains high.10-13 In the past decade, instrumented vertebral surgery has increasingly used digital navigation platforms, demonstrating the effectiveness of this technique in improving the accuracy of screw placement.14-16 We intend to analyze our experience in spinopelvic and sacropelvic stabilization by using digital navigation based on preoperative computed tomography (CT), evaluating the

MPR: Multiplanar reconstruction MRI: Magnetic resonance imaging From the Departments of 1Human Neurosciences, Neurosurgery and 2Emergency and Acceptance, Anesthesia and Critical Care Areas, UOD Emergency Orthopaedic Traumatology, Sapienza University of Rome, Rome, Italy To whom correspondence should be addressed: Fabrizio Gregori, M.D. [E-mail: [email protected]] Citation: World Neurosurg. (2019) 131:399-407. https://doi.org/10.1016/j.wneu.2019.07.050 Journal homepage: www.journals.elsevier.com/world-neurosurgery Available online: www.sciencedirect.com 1878-8750/$ - see front matter ª 2019 Elsevier Inc. All rights reserved.

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difficulties and advantages for surgeons and whether it has a favorable impact on the learning curve in this field of surgery.

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follow-up 1 year, range 1e3) was evaluated using the ASIA Impairment Scale (AIS) score.21 ILLUSTRATIVE CASES

METHODS We retrospectively investigated 25 consecutive patients who underwent screw fixations for unstable pelvic ring fractures between October 2015 and January 2017, at the Department of Emergency and Acceptance and Neurosurgical Division of the Department of Human Neuroscience, Policlinico “Umberto I,” University “Sapienza” of Rome. At the time of admission the patients underwent total-body CT scan and angio-CT scan with multiplanar reconstruction (MPR). Cervical and thoracolumbar spine fractures were classified according to Magerl et al’s17 classification modified by Vaccaro et al,18,19 while posterior pelvic ring fractures were described according to Tile’s classification.20 Once the patients’ clinical conditions were stabilized, surgical osteosynthesis of sacral fractures was performed and the surgical repair of abdominal-pelvic injury and/or osteosynthesis of limb fractures and/or anterior pelvic ring was made in 12 cases (48%). Surgical treatment was performed using a navigation technique with the Kick BrainLab (Brainlab, Westchester, Illinois, USA) system based on preoperative CT scan, after evaluation by magnetic resonance imaging (MRI) of the spine and pelvis; the team was composed of a senior orthopedic surgeon with experience in both conventional and navigated pelvic stabilization technique and a senior neurosurgeon with good knowledge of spinal imaging guidance surgery (IGS) but no experience in conventional pelvic osteosynthesis. Preoperative and long-term neurologic status (mean

Figure 1. Case 1, magnetic resonance imaging and computed tomography (CT) images of preoperation status. (A) Sagittal T2-weighted image of lumbosacral spine showed sacral fracture with anterior dislocation of S2. (B) Axial CT scan showed type C2 posterior

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Case 1 A 29-year-old female, the victim of a car accident, was transported to our hospital at the emergency department by an ambulance. On initial survey, she was alert, collaborating and complaining of severe low back pain. There was no weakness or numbness in the limbs. The rectal examination revealed a reduction perianal sensation, loose sphincter tone, and loss of voluntary contraction. Total body CT scan showed a burst spinal fracture of T7 and T11 without posterior wall involvement, IX
XI rib fractures on the right side with pneumothorax, pleural effusion, and sacral dislocated fracture with posterior translation of S2 (Figure 1B and C). Pelvic fracture was classified as C3, according to Tile et al’s20 classification. Lumbosacral MRI confirmed the dislocated sacral fracture at the S1-S2 level and sacral wing fracture with bilateral neuroforamina involvement (see Figure 1A). Ileosacral osteosynthesis with decompression of the sacral canal was performed 8 days after the traumatic event using a navigation system (Figure 2A and B). The patient was put in a prone position. A reference pin was placed on the S1 spinous process, and the camera traced the navigated instruments and displayed their position relative to each of the stored CT images. Two bilateral cannulated iliosacral screws were inserted using a guidewire in percutaneous technique. The correct screw position

pelvic ring fracture, according to Tile et al. (1996), with bilateral involvement of sacral neuroforamina. (C) 3-Dimensional reconstruction of pelvic ring and lumbosacral junction showed right iliopubic branch fracture.

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Figure 2. Case 1, screen shot of spinal navigation platform. (A) Planning phase of the iliosacral screw trajectory before positioning. (B) Postoperative axial

was controlled on intraoperative fluoroscopy and postoperative MPR CT scan (see Figure 2B). During hospitalization, she reported improvement of low back pain and began mobilization. One-year follow-up showed improvement of neurologic status. Case 25 A 56-year-old man accidentally fell from a height of about 2 m. On arrival at the emergency and acceptance department of our

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computed tomography scan showing iliosacral osteosynthesis with bilateral iliosacral screws.

hospital the patient showed a modest strength deficit in the dorsal and plantar flexion of the left foot and a hypoesthesia of the anterolateral portion of the left lower limb. The examination of sphincter function showed hypotonia of the anal sphincter with urinary incontinence. MPR CT scan showed a T12 burst fracture with irregularity of the posterior wall, fracture of L5 left transverse process, S1 and S2 sacral metamers fracture, left ileopubic and ischiopubic branch multifragmentary displaced fractures, and

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multiple rib fractures. Pelvic ring lesion was classified as C2 according to Tile et al’s20 classification (Figure 3B and C). MRI study of the column and pelvic ring confirmed the S1 and S2 bodies displaced fracture and T12 spinal fractures described by CT scan (see Figure 3A). On the 15th day after trauma, the patient underwent spinopelvic stabilization in navigation technique with iliac and spinal pedicle screws (Figure 4AeC). At 15 months’ follow-up, strength deficit in dorsal and plantar flexion of the left foot persisted while sphincter function improved.

RESULTS The mean age was 41.24 years (range 18e77), and the male-tofemale ratio was 5: 1, with male prevalence (21 males and 4 females). In 13 cases (52%) the trauma was due to precipitation by suicide attempt, in 7 cases (28%) by accidental fall, and in 5 cases (20%) by road accident. In Table 1 we report the general characteristics of the cases of our personal experience, neurologic conditions, treatments, and results achieved. Twelve patients (48%) underwent mechanical ventilation due to hypovolemic shock for severe thoracic abdominal trauma; bleeding was blocked by performing pelvic packing in 9 cases (36%) and trans-catheter embolization in 2 cases (8%). External

Figure 3. Case 25, preoperative magnetic resonance imaging and computed tomography (CT) images. (A) Sagittal T2-weighted image of thoracolumbosacral spine showed T12 type A3 fracture, according to Vaccaro et al. (2013), with posterior wall dislocation of the vertebra and sacral fracture with S2 posterior

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fixation was used to stabilize a pelvic ring lesion in 7 cases (28%). Pelvic fractures, according to Tile et al’s20 classification, were B1 in 5 cases (20%), B2 in 2 cases (8%), B3 in 2 cases (20%), C1 in 9 cases (36%), C2 in 3 cases (12%), and C3 in the remaining 4 cases (16%). The sacral segments involved were in 24 cases (96%) S1, in 23 cases (92%) S2, in 13 cases (52%) S3, in 6 cases (24%) S4, and in 3 cases (12%) S5. In 20 cases (80%) sacral fracture was associated with spinal fractures, which in 6 cases (24%) were multiple and in 14 cases (56%) affected only the lumbar spine. According to Magerl et al’s17 classification modified by Vaccaro et al,18,19 spinal fractures were A0 in 20 cases (80%), A1 in 6 cases (24%), A2 in 1 case (4%), A3 in 4 cases (16%), A4 in 2 cases (8%), and B2 in 1 case (4%). Thoracic or lumbar spinal fracture associated with the sacral lesion was included in the spinopelvic instrumented stabilization in 6 cases (24%). The preoperative neurologic status classified according to AIS21 was A in 1 case (4%), B in 3 cases (12%), C in 5 cases (20%), D in 9 cases (36%), and E in 7 cases (28%). The mean time elapsed from the first observation to surgical treatment of the pelvic lesion was 18 days (range 8e31). Surgical treatment consisted of iliosacral fixation in 19 cases (76%) and in spinopelvic fixation in 6 cases (24%). Other treatments that concerned surgical repair of abdominal-pelvic lesions and/or osteosynthesis of limbs fractures and/or anterior pelvic ring in 12 cases (48%) were performed. Iliosacral osteosynthesis was bilateral

dislocation. (B) Axial CT scan of posterior pelvic ring showed type C2 sacral fracture according to Tile et al. (1996), with bilateral involvement of the sacral neuroforamina. (C) CT inlet view of pelvic ring showed ischiopubic branch fracture on left side.

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Figure 4. Case 25, screen shots of spinal navigation platform. (A) Planning phase of iliac screw trajectory before positioning. (B) Postoperative thoracolumbopelvic computed tomography (CT) scan

in 4 cases (21.05%) and unilateral in 15 cases (78.94%), with a mean number of implanted screws of 1.37 (range 1e3) and an operation mean time of 78.93 minutes (range 61e130). The mean number of implanted screws in spinopelvic fixation cases was 9.83 (range 6e17) with an intervention mean time of 323.67 minutes (range 247e471). A wound infection occurred in 2 cases (8%), respectively 15 days and 1 month after surgery, cured in both cases by vacuum-assisted closure therapy, while 1 month later after operation in 1 case (4%) it was necessary to remove an iliac screw due to decubitus of the overlying skin. At long-term follow-up, the neurologic status according to AIS21 was E in 14 cases (56%), D in 8 cases (32%), B in 2 cases (8%), and A in 1 case (4%); an improvement of neurologic status was observed in 13 cases (52%) while it remained unchanged in 12 cases (48%).

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showing T10-ilium spinopelvic stabilization by pedicle and iliac screws. (C) Postoperative axial CT scan of posterior pelvic ring showing bilateral iliac screws.

DISCUSSION Navigation systems used in spinal instrumented surgery and arthroplasty for the treatment of deformities, tumors, and traumatic injuries, as well as in degenerative disease, have achieved wide consensus in the past 2 decades thanks to their accuracy in instrument positioning and reduced radiation exposure for patients and operators. The spread of its use is also related to the possibility of overcoming obstacles such as anatomic complexity and neurovascular structure preservation near the anatomic region to be treated.14,22-25 It shows a rapid evolution thanks to the progress of techniques and technologies in the biomedical and bioinformatic fields. In spinal surgery, navigation platforms based on 2-dimensional, 3-dimensional, or preoperative/intraoperative CT scan provide better precision in the choice of entry point and the

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Table 1. Summary of 25 Cases Who Underwent Screw Fixation for Unstable Pelvic Ring Fractures

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Site of Sacral Emergency Fracture Case Year Sex Treatment* Typey

Spinopelvic Treatment Spinal Fracture Site/Typez

Operation Initial Status Time Surgery Type/Others Number of (days) (Y-N) Screws Duration (min) AISx

Adverse Eventsk

Outcome AISx

/

C2

S1-S3

T7,T11/A1; L1-L5/A0

D

8

IS/N

2

89

None

E

35/M

MV/PP

C1

S1-S3

L4; L5/A0

B

25

SP/Y

7

263

WI 15 days

B

3

32/M

MV/TAE

C3

S1-S5

L1/A4; L5/B2

B

21

SP/Y

12

348

WI 1 year

B

4

18/F

/

C3

S2-S3

T12/A1; L3,L5/A0

D

11

SP/N

8

301

DIS 30 days

E

5

43/M

MV

C2

S1-S3

L5/A0

E

17

IS/N

2

97

None

E

6

37/M

TAE

B1

S1-S4

L1/A2; L5/A0

C

19

IS/Y

1

68

None

D

7

27/M

MV/PP/EF

C1

S1-S5

L1/A1; L2-L4/A0

D

27

IS/Y

2

95

None

E

8

34/M

MV/PP/EF

C1

S1-S2

L5/A0

E

29

IS/Y

2

100

None

E

9

30/M

/

B1

S1-S2

L4-L5/A0

D

11

IS/N

1

72

None

E

10

19/M

/

B1

S1

L1-L5/A0

D

13

IS/N

1

70

None

E

11

72/M

/

B1

S1

/

E

15

IS/N

1

69

None

E

12

36/M

/

B3

S1-S3

L3-L5/A0

D

10

IS/N

3

130

None

E

13

29/M

MV/PP/EF

B3

S1-S3

/

C

31

IS/Y

2

97

None

D

14

68/M

/

B1

S1-S2

T12/A3; L5/A0

E

12

IS/N

1

65

None

E

15

49/M

MV/EF

C1

S1-S2

L3-L4/A1; L1-L2,L5/A0

E

19

IS/N

1

67

None

E

16

77/M

/

C1

S1-S2

/

C

9

IS/N

1

71

None

D

17

54/M

MV/PP/EF

C1

S1-S2

/

E

25

IS/Y

1

71

None

E

18

44/M

MV/PP/EF

B2

S1-S3

L3-L5/A0

D

26

IS/Y

1

73

None

D

19

51/F

MV/PP/EF

B2

S1-S2

L1-L5/A0

D

28

IS/Y

1

61

None

E

20

44/M

/

C1

S1-S2

L3-L5/A0

C

11

IS/N

1

67

None

D

/

C1

S1-S4

L2/A2

C

9

IS/N

1

64

None

D

33/M

MV/PP

C1

S1-S2

/

E

29

IS/Y

1

66

None

E

23

19/M

/

C3

S1-S4

C2/A1; C7/A0; T4,T8/A0; T5-T7/A1; L4-L5/A0

B

19

SP/Y

6

247

none

D

24

51/M

MV/PP

C3

S1-S5

T11/A1; T12/A3; L2-L3/A0; L4/A4; L5/A3

A

28

SP/Y

9

312

none

A

25

56/M

/

C2

S1-S2

T12/A3; L5/A0

D

15

SP/N

17

471

none

D

DIS, decubitus of iliac screw; EF, external fixation; F, female; IS, iliosacral stabilization; M, male; MV, mechanical ventilation; PP, pelvic packing; SP, spinopelvic stabilization; TAE, transcatheter arterial embolization; WI, wound infection; Y-N, yes or no surgical repair of abdominopelvic lesions and/or limbs’ osteosynthesis and/or anterior pelvic ring fractures. *Emergency treatment. yClassification according to Tile et al.17 zClassification according to Vaccaro et al.18,19 xNeurologic status according to ASIA Impairment Scale, Frederick et al.21 kAdverse events.

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44/F

22

IN

21

INNOVATION

29/F

2

NAVIGATION TECHNIQUE FOR SACRAL FRACTURES

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Figure 5. Case 2, postoperative axial computed tomography scan of posterior pelvic ring image showing left sacroalariliac screw, right iliac screw, and preoperative transcatheter embolization of the right gluteal artery (arrow); note that to separate right iliac screw and ipsilateral gluteal artery there is only the external bone plate of the iliac bone.

pedicle screws’ trajectory. In 2009, Tian et al16 in a meta-analysis of 6063 navigated pedicle screws implanted in vivo reported accuracy of 89.59%, 86.96%, and 94.13%, respectively, using preoperative CT, 2-dimensional intraoperative fluoroscopic images, and 3-dimensional intraoperative fluoroscopic images. Likewise, in 2012 Gelalis et al14 observed that the percentage of correctly positioned screws ranged from 69% to 94% for freehand techniques, from 28% to 85% with the use of intraoperative fluoroscopy, from 81% to 92% using a fluoroscopy-based navigation system, and from 89% to 100% using the navigation system based on preoperative CT scan. These data show that in the past decade the use of navigation platforms has provided support for the improvement of instrumented arthrodesis in spinal surgery, offering a good perspective to improve the accuracy and effectiveness of the spinal instrumentation. The most recent navigation techniques based on intraoperative CT scan, such as the O-Arm, have further provided encouraging results regarding the implantation’s accuracy of pedicle screws in thoracic, lumbar, and more recently in the sacral spine as reported by Helm et al15 in a literature review concerning 32 publications on the placement of 12,622 screws with 93.7% accuracy. Surgical techniques in the treatment of pelvic instability, developed before the introduction of IGS, refer to intraoperative and fluoroscopic anatomic landmarks for the choice of entry point and optimal screws trajectory.6 The placement of iliac and sacroalarial iliac screws using intraoperative fluoroscopy allows obtaining an optimal distal anchorage point, good bone fusion rates, and a decrease in the system pull-out rate and pseudoarthrosis of the lumbosacral junction.26 Iliosacral screws in percutaneous fluoroscopic-guided technique have also become a common practice in the treatment of unstable posterior pelvic ring fractures, reducing the risk of intraoperative bleeding and infections compared with open surgery.27 These techniques require considerable knowledge of anatomy and surgical technique, resulting in difficult when the spinopelvic and sacroiliac anatomy is distorted by the fracture and the obstacle given by the pelvic soft tissues does not

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allow good visualization of radiologic landmarks on the fluoroscopic images.28,29 The “tear-drop view” is, in fact, important for obtaining a correct and safe iliosacral screw trajectory through the internal and external bone plate of the ileum, remaining at the same time z2 cm proximal to the sciatic notch.6 However, the alteration of the iliosacral anatomic relationships like in the upper burst sacral fractures (S1/S2) makes it difficult to evaluate intraoperative fluoroscopic images, causing an increased risk of malposition and complications related to spinopelvic instrumentation.6 The navigated instrumentation techniques allow surgeons to reduce these risks, thanks to trajectory visualization on the workstation even if entry point is not the conventional one; at the same time it is possible to choose the screws’ length and diameter, increasing pull-out resistance (Figure 5).30 In the treatment of our cases, neurosurgeons had no experience in placing sacropelvic instruments with conventional techniques while orthopedists did not have good knowledge of spinal navigation based on preoperative CT images. Despite respective limitations in the knowledge of surgical techniques, the use of IGS has allowed us to obtain good results in the positioning of iliac, sacroiliac, and iliosacral screws. In our experience the use of navigation platform has improved knowledge in sacropelvic and spinopelvic stabilization techniques for surgeons who used intraoperative fluoroscopic-based techniques, while it improved the learning of these techniques for surgeons who had only spinal navigation experience, as already reported in literature.31,32 However, these experiences do not indicate the total exclusion of malposition risk and we are in agreement with Takao et al33 that the only use of navigation by surgeons without experience in sacral and pelvic fractures reduces but does not delete the malposition rate. We also believe that use of IGS cannot be separated from preoperative evaluation of sacropelvic anatomy and from the intraoperative anatomic landmarks identification, which is always required when any surgical technique is used. Both the entry point and screw trajectory can be easily visualized on the navigation workstation. They must be mandatorily compatible to the entry point and direction that the surgeon would choose in the absence of the navigation system, on the basis of his experience and the 3-dimensional fracture reconstruction, on the basis of anatomic landmarks, and on accurate study of the preoperative radiologic investigations. In a few cases, the lack of such correspondence has led us to apply a more careful surgical technique, repeating the navigation procedure and performing a reevaluation of traditional anatomic and radiologic landmarks. The conventional techniques, based on fluoroscopic 2D intraoperative images, require the surgeon’s ability to “imagine” a 3-dimensional anatomic reconstruction starting from the interpretation of radiologic images and knowledge of anatomic structures. The so-called “dead reckoning of anatomy” might lead to various degrees of inaccuracy, especially for the positioning of iliosacral screws.32 Thanks to the use of a navigation system, we obtained a “double check” for the entry point planning to obtain an optimal screw direction, coupling the navigation images with the experience of the surgeon, especially for fractures of the posterior pelvic ring with a high dislodgment degree. The sole interpretation of the intraoperative radiologic images for this kind of fracture is particularly complex.

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Knowledge of surgical anatomy and technique is essential for implant success, both for the effectiveness of the instrumentation and reducing the complication rate; moreover, a good understanding of biomechanics and fracture instability are concepts connected strictly to its correct classification and therefore to correct treatment. The aim of our study is to verify the greater accuracy in screw placement and a reduction in complication rates with the use of a navigation system, as well as evaluate the difficulties and advantages related to the use of this technique and its impact on the surgeon’s learning curve. The use of navigation in our case series has not excluded the possibility of screw misplacement but has avoided a malpositioning that could involve the soft tissues, reducing the rate of related complications. A limit of our paper is related to the few cases described but might represent a perspective for further studies, evaluating the possible reduction in operative times. Takao et al31 reported that with the use of intraoperative CT with an integrated navigation system in percutaneous iliosacral screw fixation, the operation time decreased to half after the first 5 procedures and further decreased to one third after the 10th procedure. A correct fracture classification, based on preoperative CT image evaluation and injury modalities, will be decisive for

REFERENCES 1. Rodrigues-Pinto R, Kurd MF, Schroeder GD, et al. Sacral fractures and associated injuries. Glob Spine J. 2017;7:609-616. 2. Robles LA. Transverse sacral fractures. Spine J. 2009;9:60-69. 3. Schroeder GD, Kurd MF, Kepler CK, et al. The development of a universally accepted sacral fracture classification: a survey of AOSpine and AOTrauma members. Glob Spine J. 2016;6:686-694. 4. Dayer R, Ouellet JA, Saran N. Pelvic fixation for neuromuscular scoliosis deformity correction. Curr Rev Musculoskel Med. 2012;5:91-101. 5. Kebaish KM. Sacropelvic fixation: techniques and complications. Spine. 2010;35:2245-2251. 6. Yi C, Burns S, Hak DJ. Intraoperative fluoroscopic evaluation of screw placement during pelvic and acetabular surgery. J Orthopaed Trauma. 2014;28: 48-56. 7. Zwingmann J, Konrad G, Kotter E, Südkamp NP, Oberst M. Computer-navigated iliosacral screw insertion reduces malposition rate and radiation exposure. Clin Orthopaed Rel Res. 2009;467: 1833-1838. 8. Zwingmann J, Konrad G, Mehlhorn AT, Südkamp NP, Oberst M. Percutaneous iliosacral screw insertion: malpositioning and revision rate of screws with regards to application technique (navigated vs. conventional). J Trauma. 2010;69: 1501-1506. 9. van den Bosch EW, van Zwienen CMA, van Vugt AB. Fluoroscopic positioning of sacroiliac screws in 88 patients. J Trauma. 2002;53:44-48.

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management and optimal treatment of the specific case, combining the surgeon’s knowledge with the advantage of a navigated technique. CONCLUSION Use of a navigation platform based on preoperative CT scans, for instrumented spinopelvic and sacropelvic reconstruction, provides greater safety to the surgeon, reducing the learning times of techniques and malposition risk. Traumatic sacral fractures are often associated with anterior pelvic ring injury and/or spinal fractures, making the management of these lesions more complex. An interdisciplinary approach between pelvic and spinal surgery experts is essential to achieve optimal results, especially when the injury involves not only the sacrum but also pelvic ring and/or spine and the use of navigation systems could be an important meeting point. This wide view of sacral fractures, often associated with other spinal and/or pelvic lesions, demonstrates insufficient attention about their classification; there is a clear discrepancy between the fractures classification of lumbar spine and posterior pelvic ring fractures; therefore, we expect a better classification suggestion that unifies these 2 different realities.

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less-experienced surgeons. J Orthopaed Trauma. 2013;27:716-721. Conflict of interest statement: The authors declare that the article content was composed in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Received 22 May 2019; accepted 4 July 2019 Citation: World Neurosurg. (2019) 131:399-407. https://doi.org/10.1016/j.wneu.2019.07.050 Journal homepage: www.journals.elsevier.com/worldneurosurgery Available online: www.sciencedirect.com

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