Triangular Osteosynthesis of Vertically Unstable Sacrum Fractures: A New Concept Allowing Early Weight-Bearing

Transiliac-Transsacral Screw Fixation is Superior to Lumbopelvic Stabilization in the Treatment of Minimally Displaced Sacral H-/U-Type Fragility Fractures

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVES

To compare the outcomes and complications of transiliac-transsacral screw fixation (TIS) and lumbopelvic fixation (LPS), the 2 most common fixation methods for nondisplaced and minimally displaced H-/U- type sacral fragility fractures.

METHODS

Medical records of patients treated with TIS or LPS for nondisplaced and minimally displaced H-/U-type sacral fragility fractures at 2 level A trauma centers between 2012 and 2022 were analyzed. Postoperative low back pain and mobility levels were assessed as primary outcomes before discharge and at 6 weeks and 6 months postoperatively. Surgery time, blood loss, and surgical complication rates were assessed as secondary outcomes. Statistical analyses consisted of Fisher's exact tests for frequency distributions and Mann-Whitney-U tests and t-tests for group comparisons.

RESULTS

52 patients undergoing TIS (mean age: 78 ± 9 years) and 36 patients undergoing LPS (74 ± 10 years) with no discrepancy in demographic parameters were identified. There were no differences in low back pain levels between the 2 groups before surgery, before discharge, at 6 weeks postoperatively, and at 6 months postoperatively (P > 0.05). There were no differences in mobility levels before surgery, before discharge, at 6 weeks postoperatively, and at 6 months postoperatively (P > 0.05). Duration of surgery was shorter after TIS (36 ± 13 min) compared to LPS (113 ± 31 min) (P < 0.0001). Intraoperative blood loss was lower for TIS (median <20 mL) compared to LPS (median 125 mL) (P < 0.0001). Postoperative radiculopathy was less frequent after TIS (n = 1) compared to LPS (n = 3) (P > 0.05). Median length of stay was shorter after TIS (11 days) compared to LPS (14 days) (P < 0.05). Rates of reoperations directly related to the index surgery were lower after TIS (n = 2) compared to LPS (n = 10) (P < 0.01). Implant failures were observed only after LPS (n = 1).

CONCLUSION

Patients with nondisplaced and minimally displaced H-/U- type sacral fragility fractures may preferably be treated using TIS, as it is equivalent to LPS in terms of low back pain reduction and restoration of mobility, but allows for shorter operative time, less blood loss and lower reoperation rates. Prospective randomized studies should be conducted to substantiate our findings and develop distinct treatment recommendations.

Effect of different lumbar-iliac fixation and sacral slope for Tile C1.3 pelvic fractures: a biomechanical study

BACKGROUND

Lumbar-iliac fixation (LIF) is a common treatment for Tile C1.3 pelvic fractures, but different techniques, including L4-L5/L5 unilateral LIF (L4-L5/L5 ULIF), bilateral LIF (BLIF), and L4-L5/L5 triangular osteosynthesis (L4-L5/L5 TOS), still lack biomechanical evaluation. The sacral slope (SS) is key to the vertical shear of the sacrum but has not been investigated for its biomechanical role in lumbar-iliac fixation. The aim of this study is to evaluate the biomechanical effects of different LIF and SS on Tile C1.3 pelvic fracture under two-legged standing load in human cadavers.

METHODS

Eight male fresh-frozen human lumbar-pelvic specimens were used in this study. Compressive force of 500 N was applied to the L4 vertebrae in the two-legged standing position of the pelvis. The Tile C1.3 pelvic fracture was prepared, and the posterior pelvic ring was fixed with L5 ULIF, L4-L5 ULIF, L5 TOS, L4-L5 TOS, and L4-L5 BLIF, respectively. Displacement and rotation of the anterior S1 foramen at 30° and 40° sacral slope (SS) were analyzed.

RESULTS

The displacement of L4-L5/L5 TOS in the left-right and vertical direction, total displacement, and rotation in lateral bending decreased significantly, which is more pronounced at 40° SS. The difference in stability between L4-L5 and L5 ULIF was not significant. BLIF significantly limited left-right displacement. The ULIF vertical displacement at 40° SS was significantly higher than that at 30° SS.

CONCLUSIONS

This study developed an in vitro two-legged standing pelvic model and demonstrated that TOS enhanced pelvic stability in the coronal plane and cephalad-caudal direction, and BLIF enhanced stability in the left-right direction. L4-L5 ULIF did not further improve the immediate stability, whereas TOS is required to increase the vertical stability at greater SS.

Fluoroscopy guided teardrop technique for open trans-muscular iliac screw placement and open reduction maneuvers during modified triangular spinopelvic fixation for unstable U-shaped sacral and tile C pelvic traumas: technical note

Unstable traumas of the spinopelvic junction, which include displaced U-shaped sacral fractures (Roy-Camille type 2 and type 3) and Tile C vertical shear pelvic ring disruptions, occur in severe traumas patients following high speed traffic accident or fall from a height. These unstable traumas of the spinopelvic junction jeopardize one's ability to stand and to walk by disrupting the biomechanical arches of the pelvis, and may also cause cauda equina syndrome. Historically, such patients were treated with bed rest and could suffer a life-long burden of orthopedic and neurological disability. Since Schildhauer pioneer work back in 2003, triangular spinopelvic fixation, whether it is performed in a percutaneous fashion or by open reduction and internal fixation, allows to realign bone fragments of the spinopelvic junction and to resume walking within three weeks. Nevertheless, such procedure remains highly technical and it not encountered very often, even for spine surgeons working in high-volume level 1 trauma centers. Hence, this visual technical note aims to provide a few tips to guide less experience surgeons to complete this procedure safely.

Triangular osteosynthesis and lumbopelvic fixation as a valid surgical treatment in posterior pelvic ring lesions: a systematic review

Objective

Unstable fractures of the sacrum often occur in patients with pelvic fractures and represent a real challenge for the orthopedic surgeon. Triangular osteosynthesis (TOS) and lumbopelvic fixation (LP) may represent a valid management option for the treatment of this condition. We present a systematic literature review about lumbopelvic fixation and triangular fixation as treatment option for unstable sacral fractures, to assess clinical and radiological outcomes after surgery and to evaluate appropriate indications and impact on the natural history of sacral fractures.

Methods

The review is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. 50 articles out of 108 titles, were considered eligible for the full-text analysis. Finally, 16 studies that met inclusion criteria were included in this review.

Results

Overall, 212 patients (87 males, 58 females) with sacral fractures treated with TOS triangular fixation or LP lumbopelvic fixation were collected. The mean age was 37.6 years. Mean follow-up reported in all studies was 24.14 months.

Conclusion

The results presented by the different authors, highlight the effectiveness of TOS triangular fixation and LP lumbopelvic fixation for the treatment of unstable sacral fractures associated with other pelvic fractures, in terms of function, stability, cost-effectiveness, and quality of life postoperatively.

Surgical Management of Unstable U-Shaped Sacral Fractures and Tile C Pelvic Ring Disruptions: Institutional Experience in Light of a Narrative Literature Review

Unstable U-shaped sacral fractures and vertical shear Tile C pelvic ring disruptions are characterized by rare lesions occurring in patients with severe trauma. Because the initial damage-control resuscitation primarily aims to stop life-threatening bleeding, emergency treatment often includes an anterior external pelvic fixator. Delayed surgery is mandatory to allow early mobilization, reduce mortality, and improve functional outcomes. Regarding U-shaped sacral fractures, although Roy-Camille type 1 U-shaped sacral fractures can be treated with iliosacral screws, types 2 (posteriorly displaced, equivalent to AO Spine C3) and 3 (anteriorly displaced, equivalent to AO Spine C3) fractures require spinopelvic triangular fixation. Besides, proper reduction of type 2 and some type 3 sacral fractures is mandatory to prevent wound complications. In patients with neurological deficits, the need for sacral laminectomy is left at the discretion of the surgeon, given the indirect decompression already obtained with fracture reduction. Tile C pelvic disruptions with posterior ring injury located lateral to the sacral foramen can be treated with either iliosacral screws or triangular spinopelvic fixation, combined with anterior pelvic fixation. Conversely, Tile C pelvic disruptions with posterior ring injury located at, or medial, to the sacral foramen (Denis zone II or III) induce vertical lumbosacral instability and thus require spinopelvic triangular fixation with anterior pelvic osteosynthesis. Although minimally invasive techniques have been developed, open surgeries are still required for inexperienced operators and in case of major displacement. The complication rate reaches approximately 33.33% of the cases, and complications include hardware malposition, wound infection or dehiscence, hardware prominence, and sometimes hardware failure.

Biomechanical effects of S1 sacroiliac screws versus S2 sacroiliac screws on sacroiliac screws combined with a lumbar iliac fixation in the treatment of vertical sacral fractures: a biomechanical finite element analysis

OBJECTIVE

To examine the impact of sacroiliac screw position and length on the biomechanical properties of triangular osteosynthesis in treating unilateral vertical sacral fractures and provide a clinical reference.

METHODS

Unilateral Denis type II sacral fractures were modelled using finite elements to represent Tile C pelvic ring injuries. Six sacroiliac screws were used with iliolumbar fixation patterns to fix the sacral fractures, and the sacral stability, maximum pressure, and stress distribution were compared among the internal fixation modalities.

RESULTS

The best vertical stability of the internal fixation model was achieved when the S1 segment was fixed with lengthened sacroiliac screws, followed by when the S1 segment was fixed using normal sacroiliac screws. There was no significant difference in vertical stability between the S1 + S2 dual-segment fixation model and the S1-segment fixation model. The maximum pressure under a vertical force of 600 N showed a trend of L5LS1 < L5NS1 < L5LS12 < L5LS2 < L5NS2 < L5NS12.

CONCLUSIONS

In unilateral vertical sacral fractures (Denis II) treated with triangular osteosynthesis using triangular jointing combined with unilateral iliolumbar + sacroiliac screw fixation, the use of a single lengthened sacroiliac screw for the S1 segment is recommended to achieve the best vertical stability of the sacrum with less maximum compression on the internal fixation components. If it is not possible to apply a lengthened sacroiliac screw, the use of a normal sacroiliac screw for the S1 segment is recommended. Adding an S2 screw does not significantly increase the vertical stability of the sacrum.

Open Posterior Reduction and Stabilization of AO Spine C3 Sacral Fractures

AO Spine C3 sacral fractures are defined by separation of the spine including S1 from the pelvic ring and are usually result of a high-energy injury. Besides their high biomechanical instability and high rate of associated neurological impairment, these fractures are often extremely difficult to reduce due to severe bony impaction and dislocation. Additional difficulties in management of these fractures arise from only a thin-layer of soft-tissue coverage overlying the injured area.

Technical Note on Placement of Low-Profile Triangular Osteosynthesis for Unstable Posterior Pelvic Ring Injuries

SUMMARY

Triangular osteosynthesis is a technique used to stabilize posterior pelvic ring injuries. Conventional triangular fixation can be problematic for several reasons, including the need for advanced skill sets to place instrumentation, difficulty with pelvic reduction and placing the connecting construct, and prominent instrumentation. The purpose of this study is 2-fold: (1) to describe in detail a technique for lumbopelvic fixation using implants that are easy to connect, allow distraction for complex lumbosacral displacements, and are placed in a location minimizing soft tissue prominence and (2) to present our initial case series using this technique. We present a retrospective review of 18 consecutively treated patients with this technique. Inclusion criteria were patients with complete disruption through the sacrum or sacroiliac joint from blunt trauma (OTA/AO type C injuries). Outcomes included pelvic reduction/malreduction, wound healing, and complications. Fourteen patients underwent unilateral fixation (81%), and 4 patients underwent bilateral fixation (19%). All patients (18 of the 18) had a well-reduced pelvis after fixation. No patient (0%) required a return trip to the operating room for loss of reduction/malreduction, wound breakdown, or implant failure. This study presents an updated technique for a low-profile triangular osteosynthesis construct with straightforward application for unstable posterior pelvic ring injuries. This technique does not require rod bending, results in a consistently more recessed iliac screw and connecting rod, and can be used in a wide variety of unstable posterior pelvic ring injuries, including comminuted sacral fractures, L5/S1 facet fractures, and vertical shear injuries.

Lumbopelvic fixation with S2 alar-iliac screws for U-shaped sacral fractures

OBJECTIVE

To investigate the surgical methods and clinical effects of lumbopelvic fixation (LPF) with S2 alar-iliac (S2AI) screws for U-shaped sacral fractures.

METHODS

From December 2019 to August 2020, 14 patients with U-shaped sacral fractures were treated with LPF using S2AI screws. Demographics, fracture classification, mechanism of injury, surgical treatment, complications and clinical results were assessed. All patients had a LPF with or without nerve decompression. The reduction quality was evaluated according to the Matta criteria. Neurological function was evaluated according to the Gibbons grading. The activities of daily life were evaluated according to the Majeed scoring system at the last follow-up.

RESULTS

Among 14 consecutive patients with U-shaped sacral fractures, the age at injury ranged from 13 to 72 years (average 30.3 ± 17.5 years). There were 4 males and 10 females. All patients were followed up for 6-15 months (average 7.8 ± 2.7 months). Thirteen patients were fixed with bilateral S2AI screws, and one patient was fixed only unilaterally due to unilateral spinopelvic dissociation. The excellent and good rate of postoperative pelvic reduction quality was 92% (excellent 10, good 3, fair 1). At the latest follow-up, the excellent and good rate of pelvic function was 100% (excellent 9, good 5) and all patients achieved different extents of neurological recovery. One patient had a postoperative superficial surgical site infection, which healed after debridement. Radiological examination at 3-6 months after operation showed that all fractures had healed. No complications were found in any patients during follow-up, such as implant fracture, loss of reduction, deep wound infection, wound dehiscence and screw protrusion discomfort.

CONCLUSION

LPF with S2AI screws for the treatment of U-shaped sacral fractures has exhibited distinct advantages, including firm fixation, a low rate of surgical site complications and satisfactory clinical efficacy. This approach provides sufficient stability to accelerate the commencement of postoperative rehabilitation.

Team Approach: Spinopelvic Dissociation

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Spinopelvic dissociation is a complex and variable injury pattern that requires an integrated, multidisciplinary team including orthopaedic trauma and spine surgeons.

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Protocols and efficient channels of communication should be in place at tertiary Level-I trauma centers to ensure appropriate and timely treatment of patients with spinopelvic dissociation.

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Patients with spinopelvic dissociation may present with acute neurological deficits and impending cauda equina syndrome, necessitating urgent, coordinated care.

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Lumbopelvic fixation with sacroiliac screws yields a stable, multiplanar construct that connects the spine to the pelvis and allows for early mobilization.

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.

[Closed reduction and minimally invasive fixation of a sacral avulsion fracture : Minimal invasiveness with maximum stability]

Surgical stabilization of high-energy sacral avulsion fractures with spinopelvic dissociation places high demands on the surgeon. The goal is to achieve maximum stability while minimizing invasiveness. The present case of a dislocated U‑type fracture in a 25-year-old motocross rider exemplifies how a reduction with the targeted application of closed reduction techniques through hyperextension of the hip joints and lordosis in the lumbosacral hinge and through a standardized procedure in intraoperative fluoroscopic imaging, a minimally invasive stabilization by means of transsacral screw fixation and spinopelvic fixation of lumbar vertebra 5 to the ilium in the sense of a bilateral triangular stabilization is possible without compromising the achieved stability of the osteosynthesis. The limitations of the described approach are also pointed out.

Systematic review of sacroiliac joint motion and the effect of screw fixation

BACKGROUND

Pelvic injuries that disrupt the sacroiliac joints often require surgical intervention to restore stability. Quantitative characterization of sacroiliac motion in response to physiologic loading provides important metrics of adequate fixation in the evaluation of newly emerged fixation techniques. The objective of this study was to systematically review and evaluate biomechanical evidence on the motion of the sacroiliac joint in its normal, destabilized, and stabilized states.

METHODS

We searched the PubMed database for studies available until June 2020 using keywords: sacroiliac, biomechanic*, and fixation. Publications of any in vivo or in vitro biomechanical study that included measurements of the range of motion at the sacroiliac joint were considered.

FINDINGS

We identified and screened 176 total records, and 13 articles of them met inclusion criteria and were used in this review. The average sacroiliac joint range of motion of the intact pelvis was 1.88° in flexion/extension, 0.85° in lateral bending, 1.26° in axial rotation. Of the 13 studies, four reported sacroiliac motion from a destabilized state, while seven reported the motion after stabilization. A forest plot of the stabilized data set in flexion/extension showed that while the heterogeneity was poor, the weighted effect size of the changes from the intact state to the stabilized state was 0.0%.

INTERPRETATION

Quantitative evidence on sacroiliac joint motion relating to pelvic injuries or fixation is limited. Our results indicate that the pooled intact range of motion from the literature may serve as a viable reference to quantify the effectiveness of new stabilization techniques.

LEVEL OF EVIDENCE

Level V, systematic review.

STUDY TYPE

Therapeutic- investigating the results of a treatment.

Traumatic spinopelvic dissociation managed with bilateral triangular osteosynthesis: Functional and radiological outcomes, health related quality of life and complication rates

BACKGROUND

Spinopelvic dissociation (SPD) is difficult to manage and is associated with high mortality and morbidity, including concomitant orthopaedic polytrauma, spine injuries, pelvic ring disruptions, neurological, soft-tissue, and vascular injuries. The purpose of this study is to evaluate the functional and radiological outcomes; health related quality of life and complication rates of patients with traumatic spinopelvic dissociation underwent bilateral triangular osteosynthesis (TOS).

METHODS

The study was approved by the medical school's institutional review board (IRB). Prospective data collection of nineteen consecutive cases of traumatic SPD were included in the study from October 2015 to August 2018. Bilateral TOS was performed to manage all patients with SPD. The clinical outcome for fractures was analyzed with Majeed function assessment. Health Related Quality of Life (HRQoL) was assessed with the EQ-6D questionnaire. The reduction quality was evaluated according to Matta criterion. CT scanning was used to verify the fracture union in patients at 24^th weeks postoperatively.

RESULTS

There were 12 women and 7 men with an average age of 47.2±8.4 years (range, 17-62 years). The average follow-up time was 25.2±3.7 months (average, 22-45 months). The most common mechanism of injury was falling (57%). According to Majeed functional scoring, the results were excellent in 12 cases, good in 5 cases and fair in 2 cases. The median EQVAS score was 78.9±8.4. 15 patients (78.9%) turned back to their original occupation. Pain and mood disorders mainly influenced patients' present general health status. According to Matta criterion for fracture reduction, the results were excellent in 14 cases, good in 4 cases and fair in 1 case. Complications were noted as wound healing problems (26%), implant loosening (5%) and iatrogenic nerve injury (5%).

CONCLUSION

Bilateral TOS demonstrates satisfactory functional and radiological outcomes with low complication rates except infection rate in patients with traumatic spinopelvic dissociation. HRQoL is mainly dominated by pain and mood disorders. 78.9% of the patients turned back to their original occupation. Surgeons should be aware of wound healing problems in case of increased muscle mobilization and degloving injuries.Implant removal is required to improve the lumbopelvic mobility.

[Minimally invasive stabilization of sacral fractures]

BACKGROUND

Sacral fractures can be of traumatic origin and can also occur as insufficiency fractures. While the therapeutic target of mechanically stable insufficiency fractures is mainly pain relief, mechanically unstable insufficiency fractures and traumatic sacral fractures following high-energy trauma require biomechanical stabilization. Various surgical strategies are available for this, whereby minimally invasive techniques are now preferred whenever possible.

OBJECTIVE

This article presents the clinical challenges and options for minimally invasive treatment of sacral fractures.

MATERIAL AND METHODS

Selected important study data are discussed and our own treatment approach is presented.

RESULTS

The most important minimally invasive techniques for operative treatment of sacral fractures are presented: sacroiliac screw osteosynthesis, lumbopelvic stabilization and sacroplasty. The selection of the surgical technique should be made on an individual basis. While sacroiliac screw osteosynthesis is the international gold standard, diverse authors have also published minimally invasive techniques for lumbopelvic stabilization. The latter enables a higher mechanical stability. In contrast, sacroplasty should only be used as an alternative treatment in insufficiency fractures. Comparative studies of the described techniques are still missing.

CONCLUSION

All surgical options have their indications. Nevertheless, the biomechanical stability which can be achieved differs widely. Therefore, an exact analysis should be carried out of what is necessary with respect to reduction and retention and what should be achieved when treating sacral fractures.

The S2-Alar-Iliac Screw for Pelvic Trauma

Percutaneous sacro-iliac screw osteosynthesis is considered to be standard of care for most posterior pelvic ring fractures. However, special situations require alternative strategies for sufficient stabilization. In these cases, stabilization can often be achieved using posterior instrumentation e.g. using SIPS-screws (spina-iliaca-posterior-superior screws). However, this often leads to implant-related aggravation of the sometimes already critical soft tissue conditions after pelvic trauma. S2-Ala-Ilium screws (S2AI screws) are a suitable alternative. The starting point lies medial of the posterior superior iliac spine below the iliac level. It is almost in line with a potential spinal instrumentation and therefore usually causes fewer soft tissue problems. Although this technique has been widely used in spinal surgery in recent years, its use in orthopaedic traumatology is largely unknown. The possibilities but also the limitations of this technique for the treatment of injuries to the pelvis are illustrated by this retrospective case series.

Triangular Osteosynthesis Using an S1 Pedicle Screw and S2 Alar Iliac Screw for a Unilateral Vertically Displaced Sacral Fracture

BACKGROUND

Managing unilateral vertically displaced sacral fractures remains a challenge. A triangular osteosynthesis (TOS), which involves fixing the fractured sacrum using unilateral spinopelvic fixation and a supplemental ilio-sacral screw, continues to gain popularity as it facilitates early mobilization and improves the long-term outcome. However, it has limitations, such as destruction of the L5-S1 joint, the need for additional removal surgery, and an increased risk of infection due to the large incision. An S1 pediculoiliac construct was proposed to overcome this limitations. Its use also has complications, however, including a painful hardware prominence due to the traditional iliac screw, excessive soft tissue retraction, and limited reduction capability.

CASE DESCRIPTION

A 20-year-old woman fell from a height of 6 meters and sustained a vertical shear type sacral fracture on the left side with substantial vertical displacement. We reduced and fixed the fracture using a TOS using an S1 pedicle screw and an S2 alar iliac screw (S2AIS). The patient was allowed immediate weight-bearing as tolerated. We achieved good reduction and union with a small vertical incision, without the destruction of L5-S1 joints, a symptomatic implant prominence, or wound complications.

CONCLUSIONS

For unilateral vertically unstable sacral fractures, TOS using S1 pedicle screws and S2AIS is safe and has the advantage such as maintaining mobility in the lumbar pelvic region, small size wounds, and reduced soft tissue damage, and it may have a potentially low infection rate. Further studies are needed to determine the specific indications and validate the effectiveness of this procedure.

WITHDRAWN: Vertical shear pelvic ring injuries: Management algorithm

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Surgery for Unilateral Sacral Fractures: Are the Indications Clear?

OBJECTIVES

To evaluate unilateral sacral fractures and compare those treated operatively versus nonoperatively to determine indications for surgery.

DESIGN

Prospective, multicenter, observational study.

SETTING

Sixteen trauma centers.

PATIENTS/PARTICIPANTS

Skeletally mature patients with pelvic ring injury and unilateral zone 1 or 2 sacral fractures and without anteroposterior compression injuries.

MAIN OUTCOME MEASUREMENTS

Injury plain anteroposterior, inlet, and outlet radiographs and computed tomography scans of the pelvis were evaluated for fracture displacement.

RESULTS

Three hundred thirty-three patients with unilateral sacral fractures and a mean age of 41 years with a mean Injury Severity Score of 15 were included. Ninety-two percent sustained lateral compression injuries, and 63% of all fractures were in zone 1. Thirty-three percent of patients were treated operatively, including all without lateral compression patterns. Operative patients were more likely to have zone 2 fractures (54%) and to have posterior cortical displacement (29% vs. 6.2%), both with P < 0.001. Over 60% of all patients had no posterior displacement. Mean rotational displacements comparing the injured side versus the intact side were no different for patients treated operatively compared with those treated nonoperatively.

CONCLUSIONS

Most unilateral sacral fractures are minimally or nondisplaced. Many patients with radiographically similar fractures were treated operatively and nonoperatively by different surgeons. This suggests an opportunity to develop consistent indications for treatment.

LEVEL OF EVIDENCE

Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

Neurological Outcome After Traumatic Transverse Sacral Fractures: A Systematic Review of 521 Patients Reported in the Literature

BACKGROUND

The purpose of this study was to determine the neurological outcome after transverse sacral fractures in patients with neurological impairment.

METHODS

A systematic review of the English, French, German, and Dutch literature was conducted. All study designs, including retrospective cohort studies and case reports, describing transverse sacral fractures were included. Two authors independently extracted the predefined data and scored the neurological impairment according to the Gibbons classification after the trauma and at the time of follow-up. The neurological outcomes were pooled according to the Gibbons classification.

RESULTS

No randomized controlled trials or prospective case series were found. A total of 139 articles were included, consisting of 81 case reports and 58 retrospective case series involving 521 patients. Regardless of the type of management, neurological recovery of at least 1 Gibbons category was reported in 62% of these patients. A comparison of the neurological outcome of nonoperatively treated patients and surgically treated patients showed similar neurological recovery rates. For the surgically treated patients, fixation of the fracture resulted in a better neurological improvement compared with an isolated decompression.

CONCLUSIONS

This review could not provide evidence of improved neurological recovery after surgical treatment compared with nonoperative treatment. When surgical treatment was considered, there was a low level of evidence that fixation of the fracture results in better neurological improvement compared with isolated decompression.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

A novel percutaneous crossed screws fixation in treatment of Day type II crescent fracture-dislocation: A finite element analysis

Objective

Day type II crescent fracture–dislocation is a subtype of pelvic lateral compression injury. At present, there is still a controversy on the operative approach and fixation technique. We have put forward closed reduction and percutaneous crossed screws fixation for treating type-II crescent fracture–dislocation. Finite element analysis is used to compare the biomechanical properties between percutaneous crossed screws and other internal fixations.

Methods

A three-dimensional finite element model of Day type-II crescent fracture–dislocation was simulated using 5 implants, including double anterior plates (Model A), one posterior plate and one iliac screw (Model B), one sacroiliac joint screw (Model C), crossed one iliac screw and one sacroiliac joint screw (Model D), and crossed two iliac screws and one sacroiliac joint screw (Model E). 600-N stress was applied to S1 vertebral end-plate. To evaluate the biomechanical properties, the stress distribution and displacement distribution of the pelvis, stress distribution of the crescent fragment and stress distribution of plate and cannulated screw were recorded and analyzed.

Results

Under the loading of 600N, the maximum pelvic displacements in the finite element model were compared as follows: model E (0.070 ​mm), model D (0.071 ​mm), model A (0.080 ​mm), model C (0.096 ​mm), and model B (0.112 ​mm). The maximum displacements of crescent fragment were compared as follows: model E (0.018 ​mm), model B (0.022 ​mm), model D (0.023 ​mm), model A (0.030 ​mm), and model C (0.043 ​mm). The maximum stress of all implants were compared as follows: model D (90.01 ​Mpa), model E (81.60 ​Mpa), model C (69.07 ​Mpa), model A (56.51 ​Mpa), model B (18.29 ​Mpa). Model E and model D could provide better mechanical support for whole pelvic.

Conclusions

With sufficient biomechanical stability and minimally invasive advantage, percutaneous crossed screw fixation is a recommended treatment for Day Type-II Crescent Fracture–dislocation. It is recommended to fix crescent fracture fragment and sacroiliac joint simultaneously during the operation. If it is difficult to fix the both position, the sacroiliac joint is preferentially fixed.

The translational potential of this article

There is a controversy on the operative approach and fixation technique of Day type-II crescent fracture–dislocation. This article proves that percutaneous crossed screw fixation is a recommended treatment for Day type-II crescent fracture–dislocation by finite element analysis.

Traumatic Spino-pelvic Dissociation with Bilateral Triangular Fixation

OBJECTIVE

To evaluate the clinical outcomes of traumatic spino-pelvic dissociation (TSD) treated with modified bilateral triangular fixation.

METHODS

Eighteen consecutive patients of TSD were included in the study from March 2011 to March 2015, and the medical records of patients were reviewed retrospectively. There were 14 men and 4 women with an average age of 33.1 ± 1.4 years (range, 18-55 years). A total of 16 cases were caused by falling, and 2 cases were caused by traffic accident. All sacral fractures had associated injuries. According to the morphology of sacral fracture, U-shaped fractures were present in 10 cases, H-shaped fractures in 6 cases, and Y-shaped fractures in 2 cases. According to Roy-Camille classification, there were 12 cases of type II and 6 cases of type III. All patients received surgical treatment with modified bilateral triangular fixation, and the sacral plexus decompression was performed simultaneously on 6 cases whose scores were more than 2 according to Gibbons classification and were found having traumatic canal stenosis or sacral nerve compression detected by preoperative imaging examination. Mears' radiological evaluation criterion was applied to evaluate the reduction quality of fractures; Gibbons score was applied as the index of neurological deficiency healing, and the clinical outcome of fracture was evaluated with Majeed function assessment at last follow-up.

RESULTS

All patients were followed up continuously within an average of 32.4 ± 3.6 months (range, 22-48 months). All sacral fractures were healed in an average time of 11.3 ± 2.8 months (range, 8-28 months). According to the Majeed function evaluation, 12 cases were classified as excellent, 4 cases as good, and 2 cases as fair. Meanwhile, the anatomical reduction was obtained in 11 cases, satisfactory reduction in 6 cases, and unsatisfactory reduction in 1 case according to Mears' radiological evaluation criterion. The average Gibbons score changed from 2.5 ± 0.2 preoperatively to 1.4 ± 0.5 24 months postoperatively, which had a significant difference (t = 2.15, P < 0.05).

CONCLUSION

Modified triangular fixation combined with internal fixations shows satisfactory clinical outcomes in the treatment of TSD, which is recommended as an effective and advanced surgical choice.

Spinopelvic Fixation

Fixation at the lumbosacral junction continues to be a challenge for spine surgeons despite advances in spinal instrumentation techniques. The poor bone quality of the sacrum, the complex regional anatomy, and the tremendous biomechanical forces at the lumbosacral junction contribute to the high rates of instrumentation-related complications. Although many spinopelvic fixation techniques have been reported, only a few are still widely used because of the high complication rates associated with previous techniques. Spinopelvic fixation has numerous indications. Long-segment lumbar and thoracolumbar fusions to the sacrum are the most common scenarios in which instrumentation is extended to the pelvis. Surgeons performing complex spinal reconstruction should be familiar with the available techniques, including their potential risks and complications.

Current concepts in spondylopelvic dissociation

INTRODUCTION

Spondylopelvic dissociation is an uncommon and complex injury that results from high-energy trauma with axial overloading through the sacrum. Due to the life-threatening nature of these injuries, standard Advanced Trauma Life Support^® (ATLS) protocol must be used in the trauma setting as part of the initial management of these patients. The key to diagnosis is a good physical exam coupled with high level of suspicion. Radicular neurological deficits commonly are present in spondylopelvic dissociation (L5's roots) and should be documented for future evaluations. Radiographic views and CT-scan is preferred for the diagnosis.

BIOMECHANICS AND CLASSIFICATION

The authors briefly describe the anatomy and biomechanics of the pelvis, and present the main classifications used to define this rare lesion.

TREATMENT

Discussion about setting the boundaries of surgical stabilization, if there is still a role for conservative treatment, the importance of the initial treatment and the timing of intervention. Decompression is mandatory in the presence of canal compromise and progressive neurological deficit, regardless of biomechanical criteria for surgery. Kyphotic deformity occurs at the site of sacral transverse fracture and also reduces anteroposterior pelvis diameter. The technique of reduction and posterior surgical stabilization is emphasized. If residual kyphosis remains after bilateral lumbopelvic fixation by shifting of the lower sacral segment, we use S2 and/or S3 screws connected to transitional rods to additional reduction. An illustrated case is shown.

COMPLICATIONS

The infection of the wound and the failure of the implants are the most frequent complications of this surgical treatment.

CONCLUSION

Posterior stabilization is widely recognized as crucial in the treatment of pelvic disruptions. The concept of circumferential restoration of pelvic ring by bilateral lumbopelvic fixation and anterior fixation seems to be a nice option to increase stabilization and avoid bone misalignment.

Outcomes of lumbopelvic fixation in the treatment of complex sacral fractures using minimally invasive surgical techniques

BACKGROUND CONTEXT

Complex sacral fractures with vertical and anterior pelvic ring instability treated with traditional fixation methods are associated with high rates of failure and poor clinical outcomes. Supplemental lumbopelvic fixation (LPF) has been applied for additional stability to help with fracture union.

PURPOSE

The study aimed to determine whether minimally invasive LPF provides reliable fracture stability and acceptable complication rates in cases of complex sacral fractures.

STUDY DESIGN/SETTING

This is a retrospective cohort study at a single level I trauma center.

PATIENT SAMPLE

The sample includes 24 patients who underwent minimally invasive LPF for complex sacral fracture with or without associated pelvic ring injury.

OUTCOME MEASURES

Reoperation for all causes, loss of fixation, surgical time, transfusion requirements, length of hospital stay, postoperative day at mobilization, and mortality were evaluated.

METHODS

Patient charts from 2008 to 2014 were reviewed. Of the 32 patients who underwent minimally invasive LPF for complex sacral fractures, 24 (12 male, 12 female) met all inclusion and exclusion criteria. Outcome measures were assessed with a retrospective chart review and radiographic review. The authors did not receive external funding for this study.

RESULTS

Acute reoperation was 12%, and elective reoperation was 29%. Two (8%) patients returned to the operating room for infection, one (4.2%) required revision for instrumentation malposition, and seven (29%) underwent elective removal of instrumentation. No patient experienced failure of instrumentation or loss of correction. Average surgical time was 3.6 hours, blood loss was 180 mL, transfusion requirement was 2.1 units of packed red blood cells, and postoperative mobilization was on postoperative day 5. No mortalities occurred as a result of the minimally invasive LPF procedure.

CONCLUSIONS

Compared with historic reports of open LPF, our results demonstrate reliable maintenance of reduction and acceptable complication rates with minimally invasive LPF for complexsacral fractures. The benefits of minimally invasive LPF may be offset with increased elective reoperations for removal of instrumentation.

A minimally invasive surgical technique for the management of U-shape sacral fractures

INTRODUCTION

We present a small case series for the rare U-shape sacral fracture. The U-shape sacral fracture is characterised by bilateral longitudinal sacral fractures and a transverse sacral fracture through the S2 vertebral body. Historically it has been described following falls from a height and a high velocity mechanism is often required for this injury. We also describe a surgical technique for fixation of U-shape sacral fractures and subsequent implant removal 6 months post-operatively.

CASE PRESENTATION

We present the cases of three patients who presented to our institution with this injury. All patients were treated with minimally invasive, lumbo-sacro-pelvic (LSP) fixation. One patient was lost to follow-up. The remaining two patients had complete resolution of neurological function. These two patients had restoration of lumbosacral motion after removal of implants and had returned to pre-injury function.

DISCUSSION

We describe a new technique for treating U-shape sacral fractures which reduces the morbidity associated with surgery and maintains lumbosacral motion.

Pelvic trauma: WSES classification and guidelines

Complex pelvic injuries are among the most dangerous and deadly trauma related lesions. Different classification systems exist, some are based on the mechanism of injury, some on anatomic patterns and some are focusing on the resulting instability requiring operative fixation. The optimal treatment strategy, however, should keep into consideration the hemodynamic status, the anatomic impairment of pelvic ring function and the associated injuries. The management of pelvic trauma patients aims definitively to restore the homeostasis and the normal physiopathology associated to the mechanical stability of the pelvic ring. Thus the management of pelvic trauma must be multidisciplinary and should be ultimately based on the physiology of the patient and the anatomy of the injury. This paper presents the World Society of Emergency Surgery (WSES) classification of pelvic trauma and the management Guidelines.

Treatment of Unstable Posterior Pelvic Ring Fracture with Pedicle Screw-Rod Fixator Versus Locking Compression Plate: A Comparative Study

Background

The aim of this study was to assess the clinical results of treatment for unstable posterior pelvic fractures using a pedicle screw-rod fixator compared to use of a locking compression plate.

Material/Methods

A retrospective study was performed between June 2010 and May 2014 and the data were collected from 46 patients with unstable posterior pelvic ring fractures. All patients were treated using either a pedicle screw-rod fixator (study group, 24 patients) or locking compression plate (control group, 22 patients). In these patients, causes of injury included traffic accidents (n=27), fall from height (n=12), and crushing accidents (n=7). The quality of reduction and radiological grading were assessed. Clinical assessments included the operation time, times of X-ray exposures, bleeding volume during operation, incision length, and Majeed postoperative functional evaluation.

Results

No iatrogenic neurovascular injuries occurred during the operations in these 2 groups. The average follow-up time was 24.5 months. All fractures were healed. The significant differences (P<0.05) between the 2 groups were operation duration, size of incision, and intraoperative bleeding volume. Statistically significant differences in the Majeed postoperative functional evaluation and times of X-ray exposures were not found between the 2 groups.

Conclusions

Similar clinical effects were achieved in treating the posterior pelvic ring fractures using the pedicle screw-rod fixator and the locking compression plate. However, the pedicle screw-rod fixator has the advantages of smaller incision, shorter duration of the operation, and less bleeding volume compared to using the locking compression plate.

Percutaneous Lumbopelvic Fixation for Reduction and Stabilization of Sacral Fractures With Spinopelvic Dissociation Patterns

Sacral fractures that result in spinopelvic dissociation are unstable injuries that are often treated surgically, with iliosacral screw fixation and/or lumbopelvic fixation from L4 to the pelvis. Open lumbopelvic fixation allows for direct fracture reduction and immediate postoperative weight bearing, but is associated with a relatively high wound complication rate. Open surgery often takes several hours and can be associated with significant blood loss, and therefore may not be well tolerated physiologically in these patients who often have multiple injuries. We developed a percutaneous lumbopelvic reduction and fixation technique to address these issues.

Do Transsacral-transiliac Screws Across Uninjured Sacroiliac Joints Affect Pain and Functional Outcomes in Trauma Patients?

BACKGROUND

Patients with pelvic ring displacement and instability can benefit from surgical reduction and instrumentation to stabilize the pelvis and improve functional outcomes. Current treatments include iliosacral screw or transsacral-transiliac screw, which provides greater biomechanical stability. However, controversy exists regarding the effects of placement of a screw across an uninjured sacroiliac joint for pelvis stabilization after trauma.

QUESTIONS/PURPOSES

Does transsacral-transiliac screw fixation of an uninjured sacroiliac joint increase pain and worsen functional outcomes at minimum 1-year followup compared with patients undergoing standard iliosacral screw fixation across the injured sacroiliac joint in patients who have sustained pelvic trauma?

METHODS

All patients between ages 18 and 84 years who sustained injuries to the pelvic ring (AO/OTA 61 A, B, C) who were surgically treated between 2011 and 2013 at an academic Level I trauma center were identified for selection. We included patients with unilateral sacroiliac disruption or sacral fractures treated with standard iliosacral screws across an injured hemipelvis and/or transsacral-transiliac screws placed in the posterior ring. Transsacral-transiliac screws were generally more likely to be used in patients with vertically unstable sacral injuries of the posterior ring as a result of previous reports of failures or in osteopenic patients. We excluded patients with bilateral posterior pelvic ring injuries, fixation with a device other than a screw, previous pelvic or acetabular fractures, associated acetabular fractures, and ankylosing spondylitis. Of the 110 patients who met study criteria, 53 (44%) were available for followup at least 12 months postinjury. Sixty patients were unable to be contacted by phone or mail and seven declined to participate in the study. Outcomes were obtained by members of the research team using the visual analog scale (VAS) pain score for both posterior sacroiliac joints, Short Musculoskeletal Functional Assessment (SMFA), and Majeed scores. Patients completed the forms by themselves when able to return to the clinic. A phone interview was performed for others after they received the outcome forms by mail or email.

RESULTS

There were no differences between iliosacral and transsacral-transiliac in terms of VAS injured (2.9 ± 2.9 versus 3.0 ± 2.8, mean difference = 0.1 [95% confidence interval, -1.6 to 1.7], p = 0.91), VAS uninjured (1.8 ± 2.4 versus 2.0 ± 2.6, mean difference = 0.2 [-1.3 to 1.6], p = 0.82), Majeed (80.3 ± 19.9, 79.3 ± 17.5, mean difference = 1.0 [-11.6 to 9.6], p = 0.92), SMFA Function (22.8 ± 22.2, 21.0 ± 17.6, mean difference = 1.8 [-13.2 to 9.6], p = 0.29, and SMFA Bother (24.3 ± 23.8, 29.7 ± 23.4, mean difference = 5.4 [-7.8 to 18.6], p = 0.42).

CONCLUSIONS

Placement of fixation across a contralateral, uninjured sacroiliac joint resulted in no differences in pain and function when compared with standard iliosacral screw placement across an injured hemipelvis at least 1 year after instrumentation. When needed for biomechanical stability, transsacral-transiliac fixation across an uninjured sacroiliac joint can be used without expectation of positive or negative effects on pain or functional outcomes at minimum 1-year followup.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Osteosynthesis in sacral fracture and lumbosacral dislocation

Sacral fracture and lumbosacral hinge trauma are rare but serious lesions. Neurologic disorder is frequently associated, and nerve release may be required, with reduction and stabilization of the fracture. Management requires knowing the fracture lines and reduction maneuvers and the fixation techniques that may need to be associated. Three classifications allow these fractures to be well understood: the Roy-Camille classification identifies high transverse fractures and their displacement; the Denis classification identifies vertical fracture line location within the sacrum, which correlates with neurologic risk; and the Tile classification analyzes pelvic ring trauma when associated with the sacral fracture. Treatment, when surgical, requires careful patient positioning, sometimes on an orthopedic table. Reduction maneuvers are founded on the fracture classification. Isolated U-shaped fracture of the sacrum is to be distinguished from sacral fracture associated with pelvic ring lesion. Osteosynthesis may be lumbopelvic or restricted to the pelvic ring (sacroiliac or iliosacral). Open osteosynthesis allows reduction to be finalized by intraoperative maneuvers on the implant, while closed osteosynthesis requires perfect preoperative reduction. Complications are frequent and neurologic recovery is uncertain. Fatigue and osteoporotic fractures show little displacement and are good indications for cementoplasty, either isolated or associated to iliosacral screwing. In lumbosacral hinge trauma, and dislocation in particular, reduction surgery with fixation (usually 360°) is indicated. The present study details the analysis and classification of these fractures, the technical pitfalls of reduction and fixation, and treatment indications.

The cement-augmented transiliacal internal fixator (caTIFI): an innovative surgical technique for stabilization of fragility fractures of the pelvis

INTRODUCTION

Analyzing the different age groups in a population who suffered a pelvic ring fracture it becomes obvious that there are important differences between the pelvic ring lesions of an elderly patient compared to a young adult concerning trauma mechanism, fracture pattern and therapeutic options. In the elderly patient it is very important to achieve maximum of stability if surgery is necessary in order to avoid early failure of the ostheosynthesis under mobilization with full weight bearing.

PATIENTS AND METHODS

15 patients (14 female) with fragility fractures of the pelvis that required surgical stabilization were eligible to participate in this study from December 2012 to December 2014. Such details were documented and analysed as patient demographics, mechanism of injury, fracture classification, operative treatment and postoperative radiological parameters of achieved bone-implant interface.

RESULTS

The average age of the patients was 79.9 years (SD 9.0 years). According to Rommens five patients had a fragility fracture of the pelvis Type II-c, one a Type III-c, six a Type IV-b and three a Type IV-c. Four patients were treated by a cement augmented transiliac internal fixation (caTIFI). Seven patients received a cement augmented iliolumbar fixation. In all these patients the Schanz screws applied to the ilium were placed in an oblique dorsoventral direction into the supraacetabular bone canal (mean length of screws 100 ± 20mm, max. 135 mm, min. 70 mm). Even though in four patients the iliosacral joint was hit tangential and one cortex perforation without any cement leakage appeared no revision surgery was necessary. Overall the clinical findings including mobilisation with full weight bearing showed a sufficient mechanically stability in all patients.

CONCLUSION

The focus of this study was to describe the modified surgical technique of the caTIFI with placing the Schanz screws from the posterior superior iliac spine to the anterior inferior iliac spine into the supraacetabular bone canal. Usage of cannulated and perforated Schanz screws gives the opportunity to control the correct position of the screws before implanting them. Another advantage is that additional stability can be obtained by cement augmentation. We believe that the new technique of the caTIFI provides a greater intraoperative versatility and a greater mechanical stability for fragility fractures of the pelvis.

A biomechanical study of standard posterior pelvic ring fixation versus a posterior pedicle screw construct

OBJECTIVES

The purpose of this study was to biomechanically test a percutaneous pedicle screw construct for posterior pelvic stabilisation and compare it to standard fixation modalities.

METHODS

Utilizing a sacral fracture and sacroiliac (SI) joint disruption model, we tested 4 constructs in single-leg stance: an S1 sacroiliac screw, S1 and S2 screws, the pedicle screw construct, and the pedicle screw construct+S1 screw. We recorded displacement at the pubic symphysis and SI joint using high-speed video. Axial stiffness was also calculated. Values were compared using a 2-way ANOVA with Bonferroni adjustment (p<0.05).

RESULTS

In the sacral fracture model, the stiffness was greatest for the pedicle screw+S1 construct (p<0.001). There was no significant difference between the pedicle screw construct and S1 sacroiliac screw (p=1). For the SI joint model, the S1+S2 SI screws had the largest overall load and stiffness (p<0.001). The S1 screw was significantly stronger than pedicle screw construct (p=0.001).

CONCLUSIONS

The pedicle screw construct biomechanically compares to currently accepted methods of fixation for sacral fractures when the fracture is uncompressible. It should not be used for SI joint disruptions as one SI or an S1+S2 are significantly stiffer and cheaper.

Can a Thoracolumbar Injury Severity Score Be Uniformly Applied from T1 to L5 or Are Modifications Necessary?

Study Design Literature review. Objective The aim of this review is to highlight challenges in the development of a comprehensive surgical algorithm to accompany the AOSpine Thoracolumbar Spine Injury Classification System. Methods A narrative review of the relevant spine trauma literature was undertaken with input from the multidisciplinary AOSpine International Trauma Knowledge Forum. Results The transitional areas of the spine, in particular the cervicothoracic junction, pose unique challenges. The upper thoracic vertebrae have a transitional anatomy with elements similar to the subaxial cervical spine. When treating these fractures, the surgeon must be aware of the instability due to the junctional location of these fractures. Additionally, although the narrow spinal canal makes neurologic injuries common, the small pedicles and the inability to perform an anterior exposure make decompression surgery challenging. Similarly, low lumbar fractures and fractures at the lumbosacral junction cannot always be treated in the same manner as fractures in the more cephalad thoracolumbar spine. Although the unique biomechanical environment of the low lumbar spine makes a progressive kyphotic deformity less likely because of the substantial lordosis normally present in the low lumbar spine, even a fracture leading to a neutral alignment may dramatically alter the patient's sagittal balance. Conclusion Although the new AOSpine Thoracolumbar Spine Injury Classification System was designed to be a comprehensive thoracolumbar classification, fractures at the cervicothoracic junction and the lumbosacral junction have properties unique to these junctional locations. The specific characteristics of injuries in these regions may alter the most appropriate treatment, and so surgeons must use clinical judgment to determine the optimal treatment of these complex fractures.

When do anterior external or internal fixators provide additional stability in an unstable (Tile C) pelvic fracture? A biomechanical study

PURPOSE

This study aimed at evaluating the additional stability that is provided by anterior external and internal fixators in an unstable pelvic fracture model (OTA 61-C).

METHODS

An unstable pelvic fracture (OTA 61-C) was created in 27 synthetic pelves by making a 5-mm gap through the sacral foramina (posterior injury) and an ipsilateral pubic rami fracture (anterior injury). The posterior injury was fixed with either a single iliosacral (IS) screw, a single trans-iliac, trans-sacral (TS) screw, or two iliosacral screws (S1S2). Two anterior fixation techniques were utilized: external fixation (Ex-Fix) and supra-acetabular external fixation and internal fixation (In-Fix); supra-acetabular pedicle screws connected with a single subcutaneous spinal rod. The specimens were tested using a nondestructive single-leg stance model. Peak-to-peak (P2P) displacement and rotation and conditioning displacement (CD) were calculated.

RESULTS

The Ex-Fix group failed in 83.3 % of specimens with concomitant single-level posterior fixation (Total: 15/18-7 of 9 IS fixation, 8 of 9 TS fixation), and 0 % (0/9) of specimens with concomitant two-level (S1S2) posterior fixation. All specimens with the In-Fix survived testing except for two specimens treated with In-Fix combined with IS fixation. Trans-sacral fixation had higher pubic rotation and greater sacral and pubic displacement than S1S2 (p < 0.05). Rotation of the pubis and sacrum was not different between In-Fix constructs combined with single-level IS and TS fixation.

CONCLUSION

In this model of an unstable pelvic fracture (OTA 61-C), anterior fixation with an In-Fix was biomechanically superior to an anterior Ex-Fix in the setting of single-level posterior fixation. There was no biomechanical difference between the In-Fix and Ex-Fix when each was combined with two levels of posterior sacral fixation.

Comparison of two-transsacral-screw fixation versus triangular osteosynthesis for transforaminal sacral fractures

Transforaminal pelvic fractures are high-energy injuries that are translationally and rotationally unstable. This study compared the biomechanical stability of triangular osteosynthesis vs 2-transsacral-screw fixation in the repair of a transforaminal pelvic fracture model. A transforaminal fracture model was created in 10 cadaveric lumbopelvic specimens. Five of the specimens were stabilized with triangular osteosynthesis, which consisted of unilateral L5-to-ilium lumbopelvic fixation and ipsilateral iliosacral screw fixation. The remaining 5 were stabilized with a 2-transsacral-screw fixation technique that consisted of 2 transsacral screws inserted across S1. All specimens were loaded cyclically and then loaded to failure. Translation and rotation were measured using the MicroScribe 3D digitizing system (Revware Inc, Raleigh, North Carolina). The 2-transsacral-screw group showed significantly greater stiffness than the triangular osteosynthesis group (2-transsacral-screw group, 248.7 N/mm [standard deviation, 73.9]; triangular osteosynthesis group, 125.0 N/mm [standard deviation, 66.9]; P=.02); however, ultimate load and rotational stiffness were not statistically significant. Compared with triangular osteosynthesis fixation, the use of 2 transsacral screws provides a comparable biomechanical stability profile in both translation and rotation. This newly revised 2-transsacral-screw construct offers the traumatologist an alternative method of repair for vertical shear fractures that provides biplanar stability. It also offers the advantage of percutaneous placement in either the prone or supine position.

[Polytrauma with pelvic fractures and severe thoracic trauma: does the timing of definitive pelvic fracture stabilization affect the clinical course?]

BACKGROUND

The aim of this study was to investigate the influence of the surgical timing in patients with pelvic fractures and severe chest trauma on the clinical course, especially on postoperative lung function.

METHODS

A total of 47 patients were included in a prospective dual observational study. The study investigated the clinical course depending on the time of operation based on the functional lung parameters, SAPS II, SOFA and total hospital stay.

RESULTS

The average ISS was 32±6, PTS was 34±11 and TTSS was 9±3 points. The pelvic fractures were stabilized definitively after an average of 7±2 days. The early stabilization correlated significantly with a lower TTSS and SAPS II on admission (p<0.05), shorter time of ventilation (p<0.05) and stay in the intensive care unit (p<0.01) as well as the decreased need for packed red blood cells (p<0.01).

CONCLUSIONS

In this study patients with pelvic fractures and thoracic trauma benefited positively from an earlier definitive pelvic fracture stabilization with respect to a shorter time of ventilation and stay in the intensive care unit due to a lower need for red cell concentrates.

Open reduction and posterior instrumentation of type 3 high transverse sacral fracture-dislocation: technical note

The authors describe an open reduction and fixation through a posterior approach of Roy-Camille Type 3 transverse sacral fractures. This technique involves posterior staged reduction of the fracture applying distraction forces to restore the height, followed by posterior translation to restore sagittal alignment. Tips and pearls of this procedure, described for the first time in the literature, are also discussed in this report.

Spondylopelvic dissociation

Spondylopelvic dissociation is a complex injury pattern resulting in multiplanar instability of the lumbopelvis. These injuries have traditionally been known as "suicide jumper's fractures" and have recently increased in prevalence as a result of under-vehicle explosions seen in the past decade of military conflicts in the Middle East. The hallmarks of spondylopelvic dissociation are bilateral vertical sacral fractures with a horizontal component, resulting in lumbosacral instability in the sagittal and axial planes. Surgical treatment has evolved greatly and both percutaneous and open options are available, with triangular osteosynthesis being the most relied on method of fixation.

A novel fixation system for sacroiliac dislocation fracture: internal fixation system design and biomechanics analysis

BACKGROUND

Although there were many different types of fixation techniques for sacroiliac dislocation fracture, the treat remained challenging in posterior pelvic ring injury. The purpose of this study was to evaluate the biomechanical effects of a novel fixation system we designed.

METHODS

12 human cadavers (L3-pelvic-femora) were used to compare biomechanical stability after reconstruction on the same specimens in four conditions: (1) intact, (2) cable system, (3) plate-pedicle screw system, and (4) cable system and plate-pedicle screw combination system (combination system). Biomechanical testing was performed on a material testing machine for evaluating the stiffness of the pelvic fixation construct in compression and torsion.

FINDING

The cable system and plate-pedicle screw system alone may be insufficient to resist vertical shearing and rotational loads; however the combination system for unstable sacroiliac dislocation fractures provided significantly greater stability than single plate-pedicle or cable fixation system.

INTERPRETATION

The novel fixation system for unstable sacroiliac dislocation fractures produced sufficient stability in axial compression and axial rotation test in type C pelvic ring injuries. It may also offer a better solution for sacroiliac dislocation fractures.

Management of traumatic spinopelvic dissociations: review of the literature

PURPOSE

Spinopelvic dissociation is a rare high-energy injury pattern in adults associated with high morbidity and an increased rate of neurological deficits. The purpose of this article is the conception of fracture type-associated treatment recommendations.

METHODS

This article is based on our own experience with spinopelvic dissociations and a review of the current literature.

RESULTS

Bilateral vertical plus an optional transverse fracture component configures spinopelvic dissociations as "U"- or "H"-shaped, with the result of a spinopelvic dissociation. "Y"-, "T"- or "II"-shaped fractures do not necessarily belong to this entity but can be subsumed to this entity in a wider sense. The surgical treatment of these injuries remains challenging. Initial haemodynamic stabilisation represents the main goal of primary care until definitive treatment can be performed. Anatomical reduction is demanding and even more complex in fracture areas with large comminution. Surgical treatment options depend on the fracture type, including transsacral screws, sacral banding and spinopelvic fixation, plus combinations of these procedures.

CONCLUSIONS

Spinopelvic dissociations remain highly complex injuries. "U"- and "H"-shaped fractures usually require triangular fixation, whereas "II"-, "Y"- and "T"-shaped fractures might be sufficiently stabilised with transsacral screws.