A comparison of percutaneous reduction and screw fixation versus open reduction and plate fixation of traumatic symphysis pubis diastasis

Modified pedicle screw-rod fixation versus open reduction plate fixation for the management of pubic symphysis diastasis: A retrospective study

Objective

Surgical intervention and fixation is the recognized measurement to treat pubic symphysis diastasis caused by high-energy trauma. The purpose of this retrospective study was to assess the clinical application of modified pedicle screw-rod fixation (modified PSRF) and open reduction plate fixation (ORPF) for treating pubic symphysis diastasis.

Methods

The data of this retrospective analysis were collected from 32 patients with pubic symphysis diastasis managed with modified PSRF or ORPF from January 2012 to December 2017, with or without posterior fixation. Indicators of clinical assessments including operating time, intraoperative blood loss, relevant surgical complications as well as follow-up were recorded. Majeed scores were performed for functional evaluation, as well as Matta criteria were applied to evaluate the quality of reduction.

Results

The average time from injury to operation was 2.9 days in modified PSRF group and 3.2 days in ORPF group. Significant differences regarding average operation time (41.8 min versus 64.3 min) and average intraoperative blood loss (46.6 ml versus 304.6 ml) were presented between modified PSRF groups and ORPF group. Neither Majeed scores nor Matta evaluation showed a significant difference between two groups. In ORPF group, the incision infection occurred in one patient and two patients developed loosening of screws. In modified PSRF group, loosening of screws was found in one patient during the operative procedure and one patient experienced femoral nerve palsy. Irritation to the lateral femoral cutaneous nerve (LFCN) was detected in two patients in modified PSRF group.

Conclusions

Satisfactory clinical outcomes were provided with applications of both fixation methods for treating pubic symphysis diastasis. Modified PSRF, as a minimal invasive technique, could serve as an effective and reasonable option for treating pubic symphysis diastasis.Level of evidence: III: retrospective cohort study.Trial registration: researchregistry3906.

Percutaneous Fixation for Traumatic Symphysis Pubis Disruption-Are the Results Superior Compared to Open Techniques? A Systematic Review and Meta-Analysis of Clinical and Biomechanical Outcomes

INTRODUCTION

Open reduction and reconstruction plate and screws fixation (RPSF) is considered the gold standard for the treatment of traumatic symphysis pubis diastasis (SPD). Percutaneous cannulated screw fixation (PCSF) has recently gained popularity as it may reduce operative time and morbidity. The current systematic review aims to compare the clinical and radiological outcomes of PCSF and RPSF in traumatic SPD and analyze the biomechanical effectiveness of PCSF.

MATERIAL AND METHODS

The Medline, Scopus, and Cochrane databases were searched until February 2023. The primary outcomes were the incidence of implant failure and revision surgery and the amount of displacement of symphysis pubis. Secondary outcomes were the intraoperative blood loss, the scar length, the operative time, the wound infection, and the patients' functional improvement.

RESULTS

Six clinical trial studies with a total of 184 patients and nine biomechanical studies were included. There was no significant difference between the two groups regarding the incidence of implant failure, the prevalence of revision surgery, and the amount of postoperative loss of reduction (p > 0.05 for all outcomes). The intraoperative blood loss (14.9 ± 4.2 mL for PCSF versus 162.7 ± 47.6 mL for PCSF, p < 0.001) and the incision length (1.7 ± 0.9 mL for PCSF versus 8 ± 1.4 mL for PCSF, p < 0.001) were significantly lower after PCSF. The mean operative time was 37 ± 19.1 min for PCSF and 68.9 ± 13.6 min for RPSF (p < 0.001). The infection rate was less frequent in the PCSF group (3% for PCSF versus 14.3% for RPSF, p = 0.01). One clinical trial reported better functional recovery after PCSF. In all biomechanical studies, the threshold for implant failure was beyond the applied forces corresponding to daily activities.

CONCLUSIONS

PCSF for traumatic SPD is associated with less operative time, less blood loss, and a lower infection rate when compared to conventional plate techniques without increasing the incidence of postoperative fixation failure and revision surgery. Moreover, PCSF has been proven to be biomechanically sufficient for stabilization. Therefore, it should be considered an efficient and viable alternative for the reconstruction of SPD when closed reduction can be adequately achieved.

Rates and risk factors of complications associated with operative treatment of pelvic fractures

PURPOSE

Post-operative complications following fixation of pelvic fractures can lead to mortality and increased morbidity. Available literature regarding complications is heterogeneous and knowledge on risk factors is limited. This study aims to identify the most common post-operative complications and their possible risk factors following pelvic fracture surgery.

METHODS

A retrospective cohort study was performed in two level-1 trauma centers in the Netherlands between January 2015 and January 2021. Included patients were all adult patients (≥ 18 years) with an operatively treated pelvic fracture (pelvic ring and/or acetabular fractures). Post-operative complications included surgical site infections (SSI), material-related complications, neurological complications, malunion/non-union and performed reoperations. A forward stepwise multivariable logistic regression analysis was used to identify any risk factors associated with these complications.

RESULTS

Complications occurred in 55 (24%) of the 233 included patients. SSI's were most common, occurring in 34 (15%) patients. Duration of surgery (odds ratio 1.01 per minute, 95% confidence interval 1.00-1.01) and obesity (odds ratio 1.10 per BMI point, 95% confidence interval 1.29-7.52) were independent risk factors for development of SSI. Less common post-operative complications were material-related complications (8%) and neurological damage (5%).

CONCLUSION

Limiting operation time by using less invasive and less time-consuming surgical approaches may reduce the risk of SSI. More awareness and post-operative screening for early signs of SSI is mandatory, especially in obese patients. Future research should include large prospective patient cohorts to determine risk factors for other post-operative complications associated with pelvic fracture surgery.

Development and preclinical evaluation of a cable-clamp fixation device for a disrupted pubic symphysis

BACKGROUND

Traumatic separation of the pubic symphysis can destabilize the pelvis and require surgical fixation to reduce symphyseal gapping. The traditional approach involves open reduction and the implantation of a steel symphyseal plate (SP) on the pubic bone to hold the reposition. Despite its widespread use, SP-fixation is often associated with implant failure caused by screw loosening or breakage.

METHODS

To address the need for a more reliable surgical intervention, we developed and tested two titanium cable-clamp implants. The cable served as tensioning device while the clamp secured the cable to the bone. The first implant design included a steel cable anterior to the pubic symphysis to simplify its placement outside the pelvis, and the second design included a cable encircling the pubic symphysis to stabilize the anterior pelvic ring. Using highly reproducible synthetic bone models and a limited number of cadaver specimens, we performed a comprehensive biomechanical study of implant stability and evaluated surgical feasibility.

RESULTS

We were able to demonstrate that the cable-clamp implants provide stability equivalent to that of a traditional SP-fixation but without the same risks of implant failure. We also provide detailed ex vivo evaluations of the safety and feasibility of a trans-obturator surgical approach required for those kind of fixation.

CONCLUSION

We propose that the developed cable-clamp fixation devices may be of clinical value in treating pubic symphysis separation.

Identifying safe corridors for anterior pelvic percutaneous instrumentation using computed tomography-based anatomical relationships

INTRODUCTION

Percutaneous anterior pelvic ring instrumentation is performed for retrograde screw fixation of ramus fractures, as well as for repair of pubic symphysis diastasis. The anatomic relationships of critical structures around the anterior pelvic ring, such as the spermatic cord and round ligament, have been described in only a few studies regarding the risk of iatrogenic injury during surgery. Our goal is to further describe these relationships, as well as provide radiographic information on safe corridors for percutaneous fixation.

METHODS

Eighty (80) axial computed tomography scans of the abdomen, obtained for non traumatic diagnostic purposes and screened for prior abdominal trauma or procedures, were evaluated by 3 fellowship trained radiologists. Mid-symphyseal cuts were used to obtain several measurements relative to the spermatic cords (SC) or round ligaments (RL): inter-cord or inter-ligament distance, skin to cortex of symphysis distance (vertical), skin to cortex of symphysis distance (oblique), safe corridor distance (between SC/RL and femoral triangle), center safe angle (relative to bilateral ischia), maximal safe angle, and minimal safe angle.

RESULTS

There were 41 male and 39 female scans included in the final analysis. The average inter-cord distance was 50.2 mm, skin to cortex vertical distance of 43.0 mm, skin to cortex oblique distance of 83.5 mm, safe corridor distance 26.3 mm, center safe angle 19.3˚, maximal safe angle 32.3˚, and minimal safe angle 13.6˚. These were further broken down by range and gender in Table 1. Agreement between radiologists was high for these different measurements with the exception of the skin to cortex oblique distance in female patients and the maximal safe angle in female patients, due to absence of round ligament in a majority of the scans. The round ligament was only present at the mid-symphyseal level for our three reviewers in 37/39, 36/39, and 24/39 of female patient scans.

CONCLUSIONS

We have identified defined safe corridors for instrumentation of the anterior pelvic ring that can assist the surgeon in percutaneous application of fixation for fracture care.

Percutaneous screw fixation of the pubic symphysis versus plate osteosynthesis: a biomechanical study

Objectives: To compare the stability of screw fixation with that of plate fixation for symphyseal injuries in a vertically unstable pelvic injury (AO/Tile 61-C1) associated with complete disruption of the sacroiliac joint and the pubic symphysis. Methods: Eight fourth-generation composite pelvis models with sacroiliac and pubic symphyseal disruption (Sawbones, Vashon Island, WA) underwent biomechanical testing simulating static single-leg stance. Four were fixed anteriorly with a symphyseal screw, and 4 with a symphyseal plate. All had single transsacral screw fixation posteriorly. Displacement and rotation were monitored at both sacroiliac joint and pubic symphysis. Results: There was no significant difference between the 2 groups for mean maximum force generated. There was no significant difference in net displacement at both sacroiliac joint and pubic symphysis. There was significantly less rotation but more displacement in the screw group in the Z-axis. The screw group showed increased stiffness compared with the plate group. Conclusions: This is the first biomechanical study to compare screw versus plate symphyseal fixation in a Tile C model. Our biomechanical model using anterior and posterior fixation demonstrates that symphyseal screws may be a viable alternative to classically described symphyseal plating.

Percutaneous screw fixation of pubic symphysis disruption: A preliminary report

BACKGROUND

Percutaneous techniques are commonly used to treat pelvic ring disruptions but are not mainstream for fixation of pubic symphysis disruption worldwide. Potential advantages include less blood loss and lower risk of surgical site infection, especially in the morbidly obese or multiply injured patient. This study was performed to describe the clinical and radiographic outcomes of patients after percutaneous reduction and screw fixation of pubic symphysis disruption and to evaluate the preliminary safety and efficacy of this technique and its appropriateness for further study as an alternative method of fixation.

METHODS

A retrospective review was performed to identify all patients who underwent percutaneous fixation of pubic symphysis disruption by two surgeons at an academic Level I trauma center over a 3-year period. Patients underwent percutaneous reduction and fixation of the pubic symphysis using 1 or 2 fully or partially threaded 5.5, 6.5, or 7.3 mm cannulated screws in a transverse or oblique configuration. Associated posterior ring injuries were fixed with trans-sacral and/or iliosacral screws. The primary outcome of interest was loss of reduction, defined as symphysis distance greater than 15 mm measured on final AP pelvis radiograph. Secondary outcomes collected by chart review were operative time, blood loss, vascular or urologic injury, sexual dysfunction, infection, implant loosening or breakage, and revision surgery.

RESULTS

Twelve patients met criteria and primary and secondary outcomes were collected. Mean clinical and radiographic follow-up were 15 months each. One patient lost reduction. Mean operative time and blood loss were 124 min and 29 cc, respectively. No vascular or urologic injuries occurred. Two patients reported sexual dysfunction. No patients became infected or required revision surgery. Four patients underwent implant removal. Seventeen additional patients were excluded due to short follow-up and limited outcomes were collected. Two of these patients lost reduction. Three underwent implant removal.

CONCLUSION

These data support percutaneous reduction and screw fixation of pubic symphysis disruption as a potentially safe and effective method of treatment that warrants further investigation.

Biomechanical restoration of metastatic cancer-induced peri-acetabular bone defects by ablation-osteoplasty-reinforcement-internal fixation technique (AORIF): To screw or not to screw?

BACKGROUND

Minimally invasive percutaneous polymethyl methacrylate cement augmentation procedures offer numerous clinical advantages for patients with periacetabular osteolytic metastatic bone defects in contrast to open reconstructive procedures that are associated with many complications. Several techniques, such as Ablation-Osteoplasty-Reinforcement-Internal Fixation (AORIF), cementoplasty alone, and screw fixation alone are currently used. There is no consensus on optimal skeletal reinforcement of diseased bones. The purpose of this study was to determine the most effective technique of percutaneous acetabular augmentation for joint preservation, with respect to resilience on cyclic loading and fracture pattern at maximal load to failure.

METHODS

Five cohorts of hemipelvis composite bones with uniform periacetabular defects and various types of reinforcement techniques were utilized to simulate osteolytic metastasis in the weight bearing dome of the acetabulum. Five groups of hemipelves underwent finite element analysis and biomechanical testing for load to failure, energy absorption to failure, stress relaxation on cyclic loading, and fracture locations.

RESULTS

The combination of screws and bone cement augmentation demonstrated significant higher energy absorption than the cement or screw only groups (p < 0.05), and better protection of acetabulum from displaced intraarticular fractures than the screws alone oror cement only groups (p < 0.05). Resilience to cyclic loading was higheest in the screw with cement fixation group than the screw only repair (p < 0.01), though not the cement fixation only group.

INTERPRETATION

These data support the hypothesis that cementoplasty combined with screw augmentation such as the AORIF technique provides the best protection of acetabulum from massive metastatic cancer-induced acetabular fractures compared to augmentation with screws or cement alone.

A biomechanical in-vitro study on an alternative fixation technique of the pubic symphysis for open book injuries of the pelvis

PURPOSE

Implant failure rates remain high after plate fixation in pelvic ring injuries. The aim of this study was to compare an alternative fixation technique with suture-button devices and anterior plate fixation in partially stable open-book injuries.

MATERIAL AND METHODS

We acquired 16 human fresh frozen anatomic pelvic specimens. The sacrospinous, sacrotuberous, and anterior sacroiliac ligaments were bilaterally released, and the pubic symphysis transected to simulate a partially stable open-book (AO/OTA 61-B3.1) injury. The specimens were randomly assigned to the two fixation groups. In the first group two suture-button devices were placed in a criss-crossed position through the symphysis. In second group a six-hole plate with standard 3.5 unlocked bicortical screws was used for fixation. Biomechanical testing was performed on a servo-hydraulic apparatus simulating bilateral stance, as described by Hearn and Varga. Cyclic compression loading with a progressively increasing peak load (0.5 N/cycle) was applied until failure. The failure mode, the load and the number of cycles at failure and the proximal and distal distance of the symphysis during testing were compared.

RESULTS

There was no implant failure in either of the two groups. Failures occurred in nine pelvises (56.2%) at the fixation between the sacrum and the mounting jig and in seven pelvises (43.8%) in the sacroiliac joint. Neither the ultimate load nor the number of cycles at failure differed between the surgical techniques (p = 0.772; p = 0.788, respectively). In the suture button group the mean ultimate load was 874.5 N and the number of cycles at failure was 1907.9. In the plate group values were 826.1 N and 1805.6 cycles, respectively. No significant differences at proximal and distal diastasis of the symphysis were monitored during the whole loading process.

CONCLUSION

The fixation with suture button implants showed comparable results to anterior plate fixation in open-book injuries of the pelvis.

Total endoscopic anterior pelvic approach (TAPA) - A new approach to the internal fixation of the symphysis

This study presents a detailed documentation of a total endoscopic anterior pelvic approach (TAPA) for plate fixation of a symphyseal disruption. The purpose of this work is to describe a minimally invasive technique as a possible method for reducing complications and hospitalization. Other goals included giving technical recommendations and assessing potential pitfalls and problems of this new surgical approach. Surgery was performed in an interdisciplinary setting by an experienced orthopaedic and general surgeon. The first endoscopic approach used to visualize the injury was the same as is used for endoscopic hernia surgery. The repositioning of the symphysial rupture was achieved either through external fixation or indirectly with traction and a pelvic binder. Plate positioning and fixation were achieved through two additional, minimally invasive incisions. The endoscopic approach shows multiple advantages, such as no detachment of the rectus abdominis muscle and smaller skin incisions. Furthermore, this approach could lessen the incidence of hernia and postoperative pain. We see the presented technique as a simple and innovative surgical method for treating symphyseal disruption.

Trans-obturator cable fixation of open book pelvic injuries

Operative treatment of ruptured pubic symphysis by plating is often accompanied by complications. Trans-obturator cable fixation might be a more reliable technique; however, have not yet been tested for stabilization of ruptured pubic symphysis. This study compares symphyseal trans-obturator cable fixation versus plating through biomechanical testing and evaluates safety in a cadaver experiment. APC type II injuries were generated in synthetic pelvic models and subsequently separated into three different groups. The anterior pelvic ring was fixed using a four-hole steel plate in Group A, a stainless steel cable in Group B, and a titan band in Group C. Biomechanical testing was conducted by a single-leg-stance model using a material testing machine under physiological load levels. A cadaver study was carried out to analyze the trans-obturator surgical approach. Peak-to-peak displacement, total displacement, plastic deformation and stiffness revealed a tendency for higher stability for trans-obturator cable/band fixation but no statistical difference to plating was detected. The cadaver study revealed a safe zone for cable passage with sufficient distance to the obturator canal. Trans-obturator cable fixation has the potential to become an alternative for symphyseal fixation with less complications.

Symphyseal plate with trans-symphyseal cross-screws for fixation of tile-type B1 pelvic ring injuries: radiological and functional evaluation

INTRODUCTION

Failure to neutralize the different physiological forces acting on the inferior as well as the superior regions of the pubic symphysis, the long healing time, is blamed for the repeated failures of conventional superior symphyseal plating.

MATERIAL AND METHODS

A three years prospective case series study between January 2017 and December 2019 was done, to evaluate the radiological and the functional outcomes, using Matta/Tornetta and Majeed criteria respectively, of the combination of trans-symphyseal cross-screws configuration and superior symphyseal plate in Tile-type B1 pelvic injuries.

RESULTS

Thirty patients, 18 with anteroposterior compression type II and 12 with type III, with a mean follow-up of 20 months ±5 were included. Radiologically, 26 (86.6%) cases showed an excellent, one (3.3%) good and three (10%) fair outcome. Clinically, excellent outcome in 26 (86.6%) cases, good in two (6.6%) cases, and fair in two (6.6%). Intra-operative drill bit breakage occurred in three (10%) cases and was the only reported technical complication. Significant re-displacement was reported in three (10%) cases.

CONCLUSION

The open trans-symphyseal cross-screws for fixation of the superior symphyseal plate is a simple, efficient, and safe technique with the biomechanical advantages of an extra-fixation point to the inferior symphysis together with a long and a strong bony anchorage.

Fixation of Anterior Pelvic Ring Injuries

Treatment of anterior pelvic ring injuries involves both acute stabilization during the initial resuscitation and definitive fixation. Definitive management has evolved substantially over the past 40 years with improved patient mobilization and long-term outcomes. Although its use has recently declined, external fixation remains a favorable option in certain situations. Symphyseal plating is the preferred technique for stabilization of symphyseal diastasis because of superior stability and low morbidity. Ramus screws can be effective for simple ramus fractures but require a careful technique because of the proximity of neurovascular structures. The subcutaneous internal fixator provides a good option for obese patients in whom external fixation would be poorly tolerated. Regardless of fixation strategy, posterior ring reduction and stabilization is crucial.

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.

Clinical and radiological short-term outcomes of pubic symphysis diastasis treated with modified pedicle screw-rod fixation

PURPOSE

Pubic symphysis diastasis with an incidence of approximately 20% in pelvic fractures is a severe lesion which needs to be treated properly. The objective of this retrospective study was to describe and evaluate the clinical and radiological outcomes including its advantages and limitations of this modified minimal invasive technique.

METHODS

Totally 29 patients with pubic symphysis diastasis, with or without posterior ring instability, were treated by modified pedicle screw-rod fixation (modified PSRF) between January 2010 and December 2016. The duration from injury to surgery, operation time, intraoperative blood loss as well as complications were recorded. During follow-up, the functional outcomes were assessed according to the Majeed evaluation criteria 1 year postoperatively. The evaluation of the postoperative reduction quality was carried out according to Matta criteria.

RESULTS

According to Tile classification, there were 9 cases of Type B1 underwent only anterior-modified PSRF and 20 cases of Type C1 experienced anterior-modified PSRF combined with posterior fixation. The duration from injury to operation, operation time and intraoperative blood loss were 3.27 days (range 1-6 days), 42.07 min (range 38-45 min), and 46.14 ml (range 40-55 ml). The results of reduction quality were rated as excellent in 16, good in 11 and fair in 2 based on Matta criteria. The Majeed functional scores ranged from 68 to 95 and there were excellent in 15, good in 12 and fair in 2. No patients experienced incision infection. Slight loosening of middle-two screws was verified during follow-up in one patient. Two patients underwent femoral nerve palsy. Irritation to the LFCN was detected in four patients.

CONCLUSIONS

Modified PSRF can be performed as an alternative to manage pubic symphysis diastasis due to its merits of minimal invasive, less blood loss, less soft tissue injuries as well as shorter operation time, even with the early weight-bearing.

TRIAL REGISTRATION

Researchregistry3905.

Definition of infection after fracture fixation: A systematic review of randomized controlled trials to evaluate current practice

INTRODUCTION

One of the most challenging musculoskeletal complications in modern trauma surgery is infection after fracture fixation (IAFF). Although infections are clinically obvious in many cases, a clear definition of the term IAFF is crucial, not only for the evaluation of published research data but also for the establishment of uniform treatment concepts. The aim of this systematic review was to identify the definitions used in the scientific literature to describe infectious complications after internal fixation of fractures. The hypothesis of this study was that the majority of fracture-related literature do not define IAFF.

MATERIAL AND METHODS

A comprehensive search was performed in Embase, Cochrane, Google Scholar, Medline (OvidSP), PubMed publisher and Web-of-Science for randomized controlled trials (RCTs) on fracture fixation. Data were collected on the definition of infectious complications after fracture fixation used in each study. Study selection was accomplished through two phases. During the first phase, titles and abstracts were reviewed for relevance, and the full texts of relevant articles were obtained. During the second phase, full-text articles were reviewed. All definitions were literally extracted and collected in a database. Then, a classification was designed to rate the quality of the description of IAFF.

RESULTS

A total of 100 RCT's were identified in the search. Of 100 studies, only two (2%) cited a validated definition to describe IAFF. In 28 (28%) RCTs, the authors used a self-designed definition. In the other 70 RCTs, (70%) there was no description of a definition in the Methods section, although all of the articles described infections as an outcome parameter in the Results section.

CONCLUSION

This systematic review shows that IAFF is not defined in a large majority of the fracture-related literature. To our knowledge, this is the first study conducted with the objective to explore this important issue. The lack of a consensus definition remains a problem in current orthopedic trauma research and treatment and this void should be addressed in the near future.

Non-anatomic fixation for longstanding traumatic pubic diastasis using a bone graft: A report of two cases

The incidence of internal fixation failure of symphysis diastasis varies from 6% to 75%. Hardware breakage or migration and symphysis disruption recurrence are often asymptomatic and only in a few cases reoperation is required. This report describes the managements of two cases after failed internal fixation and neglected traumatic symphysis diastasis when it was technically impossible to achieve anatomical reduction of the anterior pelvic ring. Internal fixation and a bone graft for the symphysis without anatomical reposition were performed. Both of the patients achieved good results and had no complaints of pain during daily activities. Restoration of the anatomy should not be the aim in treating recurrence of the symphysis diastasis after failed fixation. The aim of the surgery was static fixation of the anterior pelvic ring with bone grafting.

Computed tomography-based three-dimensional visualisation of bone corridors and trajectories for screws in open reduction and internal fixation of symphysis diastasis: a retrospective radiological study

INTRODUCTION

Typical stabilisation of pelvic open book injuries consists of plate fixation of the symphysis. No previous literature has been published about the evaluation of screw placement and their trajectory with four oblique 4.5 mm screws using a four-hole plate in symphysis diastasis. The aim of this study was to define insertion points and angles of trajectory for crossed screw placement regardless of any plate design based on an analysis of three-dimensional computed tomography data sets.

METHODS

One hundred human pelvic CT data sets were collected. Unilateral and bilateral placements of crossed 4.5 mm screws were simulated. Primary outcome measure was successful simulated screw placement without cortical breach. Secondary outcome measures included the anatomical measurements of the screw positions.

RESULTS

Simulated screw placement of two oblique screws on each side of the pubic symphysis without cortical breach was achieved in all (100 %) cases. There were a total of 400 screw simulations. Medial screws were longer, lateral screws had higher coronal angles, and the distance between both screws was higher on the right side (p < 0.001 each). The lengths of the right lateral, right medial, left lateral, and left medial screws were 44.9, 65.8, 45.4, and 67.4 mm, respectively. The sagittal angles to the dorsal surface area of the pubic rami were 10.5°, 11.1°, 9.0°, and 11.0°. The coronal angles to the vertical axis of the symphysis measured 39.5°, 16.0°, 33.8°, and 16.8°. The distances between these screws and the medial edge of the pubic crest were 33.5, 8.6, 29.5, and 7.3 mm. Furthermore, certain sex- and side-related differences were noted.

CONCLUSIONS

This series provides results about the feasibility and a detailed anatomical description of crossed screw placement. This is of special interest in pelvic surgery for choosing the entry points, safe screw channel parameters, and trajectories.

Is cannulated-screw fixation an alternative to plate osteosynthesis in open book fractures? A biomechanical analysis

OBJECTIVES

The current biomechanical work compares the symphyseal and sacroiliac stability obtained with two systems of bone osteosynthesis. The two methods of fixation compared were the 6-hole suprapubic non-locked plate and pubic fixation with two cannulated screws, a novel technique that can be applied percutaneously in the clinical practice. The aim of this study was to examine the validity of the use of two-cannulated-screws osteosynthesis in order to minimize the secondary effects of open fixation, especially in patients in whom an open reduction is contraindicated.

MATERIALS AND METHODS

A biomechanical study was designed in 9 fresh, human pelvis specimens, simulating an AO B1.1 type injury, using both fixation systems sequentially in each specimen. In both parts of the test, the specimens were subjected to an axial load of 300N. Displacements and rotations between the different pelvic elements were studied by means of a discrete set of points. The absence of differences between the two systems has been set as the null hypothesis.

RESULTS

There were significant differences in favor of the cross-cannulated screws in most of the displacements measured at the pubic symphysis and sacroiliac joint.

CONCLUSIONS

Fixation of the AO B1.1 type fractures with cross cannulated screws restores the biomechanical behavior of the pubic symphysis, obtaining better stability than fixation with the 6-hole non-locked plate. To date, no comparative, biomechanical studies have been conducted with these two systems of osteosynthesis. This study demonstrates that cross-cannulated screws fixation of the pubic symphysis in AO B1.1 pelvic fractures should be considered as an alternative to the conventional plating system.

Percutaneous fixation of traumatic pubic symphysis diastasis using a TightRope and external fixator versus using a cannulated screw

Background

The aim of the study was to introduce a new percutaneous technique for the treatment of traumatic pubic symphysis diastasis using a TightRope and external fixator. A comparison between this technique and percutaneous fixation using a cannulated screw was performed.

Methods

From January 2009 to December 2013, 26 patients with type II traumatic pubic symphysis diastasis were treated at two level 1 regional trauma centers. Among them, 10 patients were treated with a percutaneous TightRope and external fixator and 16 patients were treated with percutaneous cannulated screw fixation. Functional outcomes were evaluated using the Majeed scoring system. Patient satisfaction was evaluated using the modified visual analog scale. Radiological results were assessed based on the width of pubic symphysis preoperatively, immediately postoperatively, and at the final follow-up. Postoperative complications were also recorded.

Results

There were no significant differences between the groups in Majeed scores and patient satisfaction (p > 0.05). There were no significant differences in the width of pubic symphysis preoperatively, immediately postoperatively, and at the final follow-up (p > 0.05). No significant differences were found regarding infection, fixation failure, or the need for revision surgery (p > 0.05).

Conclusions

The new percutaneous technique using a TightRope and external fixator is a successful alternative for the treatment of type II traumatic pubic symphysis diastasis, which results in similar outcomes comparing to percutaneous cannulated screw fixation.

Comparison of Biomechanical Characteristics and Pelvic Ring Stability Using Different Fixation Methods to Treat Pubic Symphysis Diastasis: A Finite Element Study

The intention of this study was to compare the biomechanical characteristics using 5 internal fixation methods used clinically to stabilize a pubic symphysis diastasis (PSD, Tile type B1).A 3-dimensional finite element model of PSD was simulated using 5 implants, including single superior plate (Single-Plate), superior and anterior plate (Dual-Plate), single cannulated screw (Single-Screw), crossed dual cannulated screws (Cross-Screw), and parallel dual cannulated screws (Para-Screw). Three loads were distributed in all models, including dual-leg standing, single-leg stance, and rotation. To evaluate the biomechanical properties, the construct stiffness, the stress distribution, and the von Misses stress were recorded and analyzed. To evaluate pelvic ring stability, the micromotion of the pubic symphysis and iliosacral joint was analyzed.Disruption of pubic symphysis dramatically decreased the pelvic ring stability. Cross-screw and Para-Screw showed higher stiffness than other methods. All implants endured the maximum von Misses stress under single-leg stance. For Plate-Screw system, the maximum stress occurred at a place where it strides over pubic symphysis and adjacent Plate-Screw interface. The single implant and Para-Screw had a tendency to fail. Para-Screw showed the best fixation effect under dual-leg conditions. Cross-screw showed superior antishearing force capacity under single-leg stance. Dual-Plate provided maximum antihorizontal rotation. Para-Screw provided the maximum stabilization for the posterior pelvic ring.This study showed the biomechanical advantages of dual-implant for PSD only from the finite element view. The Para-Screw provided high construct stiffness under 3 load conditions. The single implant and Para-Screw had a tendency to fail. The better anterior and posterior pelvic stabilization were obtained by the dual-implant fixation than other methods. Therefore, the Cross-Screw and Dual-Plate fixation methods should be preferred in the treatment of pubic symphysis from the finite element view.

Percutaneous Screw Fixation of Crescent Fracture-Dislocation of the Sacroiliac Joint

Crescent fracture-dislocation of the sacroiliac joint (CFDSIJ) is a type of lateral compression pelvic injury associated with instability. Open reduction and internal fixation is a traditional treatment of CFDSIJ. However, a minimally invasive method has never been reported. The purpose of this study was to assess the outcome of closed reduction and percutaneous fixation for different types of CFDSIJ and present their clinical outcome. The authors reviewed 117 patients diagnosed with CFDSIJ between July 2003 and July 2013. Closed reduction and percutaneous fixation was performed in 73 patients. Treatment selection was based on Day's fracture classification. For type I fractures, fixation perpendicular to the fracture line were performed. For type II fractures, crossed fixation was performed. For type III fractures, fixation was performed with iliosacral screws. Forty-four patients were treated by open reduction and plate fixation. Demographics, fracture pattern distribution, blood loss, incision lengths, revision surgeries, radiological results, and functional scores were compared. All 117 patients were followed for more than 6 months (mean, 14 months [range, 6-24 months]). Blood loss, extensive exposure, duration of posterior ring surgery, duration of hospital stay, and infection rates were lower in the closed group (P<.01). Patients in the closed group achieved better functional performance (P<.01). There were no significant differences in reduction quality (P=.32), revision surgery rates (P=.27), and iatrogenic neurologic injuries (P=.2) between the 2 groups. The authors' results indicate that closed reduction and percutaneous fixation is a safe and effective surgical method for CFDSIJ.

Comparison of reconstruction plate screw fixation and percutaneous cannulated screw fixation in treatment of Tile B1 type pubic symphysis diastasis: a finite element analysis and 10-year clinical experience

Objective

The objective of this study is to compare the biomechanical properties and clinical outcomes of Tile B1 type pubic symphysis diastasis (PSD) treated by percutaneous cannulated screw fixation (PCSF) and reconstruction plate screw fixation (RPSF).

Materials and Methods

Finite element analysis (FEA) was used to compare the biomechanical properties between PCSF and RPSF. CT scan data of one PSD patient were used for three-dimensional reconstructions. After a validated pelvic finite element model was established, both PCSF and RPSF were simulated, and a vertical downward load of 600 N was loaded. The distance of pubic symphysis and stress were tested. Then, 51 Tile type B1 PSD patients (24 in the PCSF group; 27 in the RPSF group) were reviewed. Intra-operative blood loss, operative time, and the length of the skin scar were recorded. The distance of pubic symphysis was measured, and complications of infection, implant failure, and revision surgery were recorded. The Majeed scoring system was also evaluated.

Results

The maximum displacement of the pubic symphysis was 0.408 and 0.643 mm in the RPSF and PCSF models, respectively. The maximum stress of the plate in RPSF was 1846 MPa and that of the cannulated screw in PCSF was 30.92 MPa. All 51 patients received follow-up at least 18 months post-surgery (range 18–54 months). Intra-operative blood loss, operative time, and the length of the skin scar in the PCSF group were significantly different than those in the RPSF group. No significant differences were found in wound infection, implant failure, rate of revision surgery, distance of pubic symphysis, and Majeed score.

Conclusion

PCSF can provide comparable biomechanical properties to RPSF in the treatment of Tile B1 type PSD. Meanwhile, PCSF and RPSF have similar clinical and radiographic outcomes. Furthermore, PCSF also has the advantages of being minimally invasive, has less blood loss, and has shorter operative time and skin scar.