Percutaneous fixation of the pelvic ring: an update

Intraoperative computerised tomography scan for percutaneous fixation of the pelvis: a retrospective case series

PURPOSE

Fractures and dislocations of the pelvic ring are complex injuries that when treating require meticulous attention to detail and often specialized technical skill. These injuries can be the result of high-energy trauma, particularly in younger patients, or low energy trauma more often found in the elderly. Regardless of mechanism, these injuries lie on a spectrum of severity and can be treated conservatively or surgically. Percutaneous fixation under fluoroscopic guidance is the preferred standard technique when treating these fractures. This technique can be challenging for a variety of reasons including patient characteristics, intra-operative image quality, fracture morphology, among others.

METHODS

This retrospective study evaluated the use of intra-operative computed tomography (CT) using an O-arm imaging system for critical evaluation of fluoroscopic-guided screw placement in twenty-three patients. We retrospectively reviewed all cases of patients who were treated by three fellowship-trained orthopaedic traumatologists during a one-year span. Patients undergoing percutaneous pelvis fixation using both standard fluoroscopy and intraoperative CT with the Medtronic O-arm® (Minneapolis, MN) imaging system. Additionally, procedures performed included open reduction internal fixation (ORIF) of the pelvic ring, acetabulum, and associated extremity fractures.

RESULTS

Twenty-three patients were included in this study. On average, the use of intraoperative CT added 24.4 min in operative time. Five patients (21.7%) required implant adjustment after O-arm spin. Fourteen patients underwent additional post-operative CT. No secondary revision surgeries were attempted after any post-operative CT.

CONCLUSIONS

Our study suggests that intra-operative CT scan, compared to post-operative CT scan, can be utilized to prevent take-back surgery for misplaced implants and allow for adjustment in real-time.

Description of Standardized Planes and Angles for Percutaneous Supra-acetabular Screw Placement

BACKGROUND

Percutaneous screw fixation for pelvic fractures has become a minimally invasive alternative to an open operation. The complex anatomy of the pelvis renders this procedure challenging. The objective of this study was to assess standardized angles and dimensions of safety zones within a 3 D computed tomography model for optimal supra-acetabular screw placement.

METHODS

Computed tomography scans of 107 patients that suffered major trauma without showing any bone injury of the pelvis were collected. Using a software-based analysis, raw computed tomography data were transformed into 3 D models to set standardized landmarks and determine the possible insertion corridor.

RESULTS

Screws not exceeding a length of 97 mm in females and 106.4 mm in males were, in 95% of the evaluated cases, insertable without cortical bone penetration. The safety zone was 6.6 mm for females and 7.9 mm for males. Screws not exceeding these diameters were safely insertable in 95% of the cases. For the midsagittal plane, the angle was 36.4 ± 5.1 on the left and 34.7 ± 2.9 on the right (p = 0.008). For the anterior pelvic plane, the angle was 31.3 ± 4.5° on the left and 34.0 ± 4.8° on the right (p = 0.008).

CONCLUSIONS

Percutaneous fixation using supra-acetabular screws is a promising method to treat simple supra-acetabular fractures. These results may improve its safe utilization and could facilitate its broader clinical application.

Anterior internal versus external fixation of unstable pelvis fractures was not associated with discharge destination, critical care, length of stay, or hospital charges

PURPOSE

Determine if anterior internal versus supra-acetabular external fixation of unstable pelvic fractures is associated with care needs or discharge.

METHODS

A retrospective cohort study was performed at two tertiary trauma referral centers. Adults with unstable pelvis fractures (AO/OTA 61B/61C) who received operative fixation of the anterior and posterior pelvic ring by two orthopedic trauma surgeons from October 2020 to November 2022 were included. The primary outcome was discharge destination. Secondary outcomes included intensive care unit (ICU) or ventilator days, length of stay, and hospital charges.

RESULTS

Eighty-three eligible patients were 38.6% female, with a mean age of 47.2 ± 20.3 years and BMI 28.1 ± 6.4 kg/m2. Fifty-nine patients (71.1%) received anterior pelvis internal fixation and 24 (28.9%) received external fixation. External fixation was associated with weight-bearing restrictions (91.7% versus 49.2%, p = 0.01). No differences in demographic, functional status, insurance type, fracture classification, or injury severity measures were observed by treatment. Internal versus external anterior pelvic fixation was not associated with discharge to home (49.2% versus 29.2%, p = 0.10), median ICU days (3.0 [interquartile range (IQR) 7.8 versus 5.5 [IQR 4.3], p = 0.14, ventilator days (0 [IQR 6.0] versus 0 [IQR 2.8], p = 0.51), length of stay (13.0 [IQR 13.0] versus 17.5 (IQR 20.5), p = 0.38), or total hospital charges (US dollars 180,311 [IQR 219,061.75] versus 243,622 [IQR 187,111], p = 0.14).

CONCLUSIONS

Anterior internal versus supra-acetabular external fixation of unstable pelvis fractures was not significantly associated with discharge destination, critical care, hospital length of stay, or hospital charges. This sample may be underpowered to detect differences between groups.

LEVEL OF EVIDENCE

Therapeutic Level IV.

Critical distance of the sacroiliac joint for open reduction using screw fixation for traumatic sacroiliac joint diastasis: a retrospective study

BACKGROUND

Osteosynthesis for sacroiliac joint (SIJ) diastasis using an iliosacral screw (ISS) and a trans-iliac-trans-sacral screw (TITSS) can be performed using a closed or an open method. However, no clear indication for open reduction has been established.

METHODS

Data on patients with unilateral traumatic SIJ diastasis who underwent ISS and TITSS fixation were retrospectively collected and separated into groups according to the reduction method: closed reduction group (C group) and open reduction group (O group). Demographic data and perioperative image assessments were compared between the groups. The critical distance of the SIJ was identified to elucidate the indication for open reduction of the diastatic SIJ.

RESULTS

Fifty-six patients met the inclusion criteria over a 3-year period. There was no significant difference in the reduction quality of pelvic ring injuries between the groups, according to Matta's and Lefaivre's criteria. The improvement in the SIJ distance was significantly greater in the O group than in the C group in the axial plane on multiplanar computed tomography (p = 0.021). This model predicted that a difference of > 3.71 mm between the injured and healthy SIJ was a recommended indication for open reduction, with an area under the curve of 0.791 (95% confidence interval 0.627-0.955, p = 0.004).

CONCLUSIONS

Open reduction for SIJ diastasis might achieve better reduction quality than does closed reduction in the axial plane in selected cases. When the difference between the injured and healthy SIJ was wider than 3.71 mm, open reduction was recommended for satisfactory radiological outcomes.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Identification of subtle residual sacroiliac joint flexion and extension malreductions in AO/OTA 61-C1.2 (APC3) pelvic injuries after provisional anterior ring reduction

PURPOSE

Hemipelvis reduction in the setting of AO/OTA 61-C1.2 (APC3) pelvic injuries can be challenging. A common strategy is to provisionally reduce or fix the anterior ring prior to definitive fixation of the posterior ring. In this scenario, it is difficult to assess whether residual sacroiliac joint (SIJ) widening is due to hemipelvis flexion/extension or lateral displacement. This simulation sought to identify a radiographic marker for posterior ilium flexion or extension malreduction in the setting of a reduced anterior ring.

METHODS

Symphyseal and both anterior and posterior SIJ ligaments were cut in 8 cadaveric pelvis. The symphysis was reduced and wired. One centimeter of posterior flexion or extension at the SIJ was created to mimic the clinical scenario of hemipelvis flexion or extension malreduction, and a lateral compressive force was applied. SIJ widening and the direction of anterior or posterior ileal displacement relative to the contralateral joint were assessed via inlet views. SIJ widening and the direction of cranial or caudal ileal displacement were assessed using outlet views. Comparisons between flexion and extension models used Fisher's exact test.

RESULTS

On outlet views, all flexed hemipelvis demonstrated caudal ileal translation at the superior SIJ, in contrast to all extended hemipelvis demonstrated cranial translation (p < 0.0005); the scenarios were easily distinguishable. Conversely, inlet imaging was unable to identify the direction of malreduction. Flexion/extension scenarios resulted in similar amounts of SIJ widening.

CONCLUSION

Residual flexion and extension hemipelvis malreductions in APC3 injuries after provisional anterior fixation can be differentiated by the direction of ileal displacement at the superior SIJ on the outlet view.

Percutaneous Ilioilial Fixator Versus Percutaneous Iliosacral Screw in Managing Unstable Sacral Fractures: A Prospective Randomised Controlled Study

INTRODUCTION

Unstable sacral fractures with pelvic fractures are challenging to both surgeons and patients, particularly in the immediate post-injury phase and later when definitive fixation is undertaken. Percutaneous iliosacral screw fixation is widely regarded as the gold standard treatment for unstable sacral fractures without spinopelvic dissociation. Closed reduction and percutaneous fixation using iliosacral screws for sacral fractures provide early stabilisation without the need for extensive surgical exposure, thereby mitigating major complications associated with open surgical procedures. A new technique for stabilising unstable sacral fractures is the minimally invasive ilioilial fixator, also called a transiliac internal fixator (TIIF), which has gained more attention for its ability to address challenges associated with sacroiliac screw fixation. The objective of this study is to compare the functional, radiological, and surgical outcomes between the percutaneous iliosacral screw and the ilioilial fixator.

METHODS

A total of 51 patients with sacral fracture injuries sustained between August 2019 and November 2021 were included in this study, with 25 patients in Group A and 26 patients in Group B. Patient randomization was done using computer-generated randomization facilitated by Random Allocation Software (Mahmood Saghaei, Isfahan, Iran). All patients underwent the chosen intervention within 10 days of the trauma. Patients had follow-up at two weeks, six weeks, and 12 months post-treatment. The results of fixation were evaluated radiologically based on the Matta and Tornetta grading system and clinically using the Majeed pelvic scoring system. Complications were detected in both groups during follow-up visits.

RESULTS

The study found no statistically significant differences between the two patient groups in terms of final clinical assessment (p=0.79), radiological assessment (p=0.78), or the need for another operation (p=1.0). Moreover, there were no statistically significant differences between the groups with respect to complication rates (p=0.63) or the time of union (p=0.14). No differences were noted in terms of intraoperative blood loss (p=0.93) or operative time (p=0.34) but for longer incision length in the ilioilial fixator group (p<0.001) and an increased risk of intraoperative radiation exposure in the iliosacral screw group (p<00.1).

DISCUSSION

Although the iliosacral screw is considered a gold standard for unstable sacral fracture, a TIIF is a good alternative with a very satisfactory outcome.

CONCLUSION

Although the iliosacral screw still remains the gold standard for the management of sacral fractures, the ilioilial fixator emerges as a good alternative with comparable functional and radiological outcomes.

Augmented reality-based surgical navigation of pelvic screw placement: an ex-vivo experimental feasibility study

BACKGROUND

Minimally invasive surgical treatment of pelvic trauma requires a significant level of surgical training and technical expertise. Novel imaging and navigation technologies have always driven surgical technique, and with head-mounted displays being commercially available nowadays, the assessment of such Augmented Reality (AR) devices in a specific surgical setting is appropriate.

METHODS

In this ex-vivo feasibility study, an AR-based surgical navigation system was assessed in a specific clinical scenario with standard pelvic and acetabular screw pathways. The system has the following components: an optical-see-through Head Mounted Display, a specifically designed modular AR software, and surgical tool tracking using pose estimation with synthetic square markers.

RESULTS

The success rate for entry point navigation was 93.8%, the overall translational deviation of drill pathways was 3.99 ± 1.77 mm, and the overall rotational deviation of drill pathways was 4.3 ± 1.8°. There was no relevant theoretic screw perforation, as shown by 88.7% Grade 0-1 and 100% Grade 0-2 rating in our pelvic screw perforation score. Regarding screw length, 103 ± 8% of the planned pathway length could be realized successfully.

CONCLUSION

The novel innovative system assessed in this experimental study provided proof-of-concept for the feasibility of percutaneous screw placement in the pelvis and, thus, could easily be adapted to a specific clinical scenario. The system showed comparable performance with other computer-aided solutions while providing specific advantages such as true 3D vision without intraoperative radiation; however, it needs further improvement and must still undergo regulatory body approval. Future endeavors include intraoperative registration and optimized tool tracking.

Intraoperative Imaging Challenges During Pelvic Ring Disruptions and Acetabular Fracture Surgery

Achieving high-quality intraoperative imaging is crucial for successful pelvic ring and acetabular fracture surgery, yet it remains clinically challenging. Due to the complex anatomy of the pelvic ring and acetabulum, it is necessary to obtain multiple images oriented in different planes to reliably confirm reduction accuracy and implant positioning. Intraoperative image quality can be compromised by factors such as patient body habitus, bowel gas, abdominal packing, contrast dye, and nonstandardized language between surgeon and radiology technician. This article reviews common intraoperative imaging challenges encountered during pelvic ring and acetabular fracture surgery, while providing practical and evidence-based solutions and prevention strategies.

The Anatomic Position of the Sciatic Nerve During Percutaneous Retrograde Posterior Column Fixation Is Determined by Hip Position

OBJECTIVES

There are multiple established patient positions for placement of a percutaneous retrograde posterior column screw for fixation of acetabulum fractures. The sciatic nerve is at risk of injury during this procedure because it lies adjacent to the start point at the ischial tuberosity. The purpose of this study was to define how the position of the sciatic nerve, relative to the ischial tuberosity, changes regarding the patient's hip position.

METHODS

In a cohort of 11 healthy volunteers, ultrasound was used to measure the absolute distance between the ischial tuberosity and the sciatic nerve. Measurements were made with the hip and knee flexed to 90 degrees to simulate supine and lateral positioning and with the hip extended to simulate prone positioning. In both positions, the hip was kept in neutral abduction and neutral rotation.

RESULTS

The distance from the lateral border of the ischial tuberosity to the medial border of the sciatic nerve was greater in all subjects in the hip-flexed position versus the extended position. The mean distance was 17 mm (range, 14-27 mm) in the hip-extended position and 39 mm (range, 26-56 mm) in the hip-flexed position ( P < 0.001).

CONCLUSIONS

The sciatic nerve demonstrates marked excursion away from the ischial tuberosity when the hip is flexed compared with when it is extended. The safest patient position for percutaneous placement of a retrograde posterior column screw is lateral or supine with the hip flexed to 90 degrees.

Union and displacement characteristics following percutaneous screw fixation of superior pubic rami fractures

PURPOSE

To determine union and displacement metrics following percutaneous screw fixation (antegrade or retrograde) of superior pubic rami fractures.

METHODS

This is a retrospective cohort study from a single level 1 trauma center. Skeletally mature patients with at least one superior pubic ramus fracture present as part of a lateral compression-type pelvic ring injury were included.

RESULTS

Eighty-five (85) patients with 95 superior pubic rami fractures met the study's inclusion criteria. LC1, LC2, and LC3 injuries occurred in 76.5%, 15.3%, and 8.2% of patients, respectively. The majority of patients underwent concurrent posterior pelvic ring fixation (94.1%). Superior ramus screw placement occurred predominantly via retrograde technique (81.1%) with cannulated screws of size 6.5 mm or larger (93.7%). Of the 95 eligible fractures, 90 (94.7%) achieved union at a mean of 14.0 weeks (7-40 weeks). Of these united fractures, 69 (76.7%) healed with no measurable displacement, while the remaining 23.3% healed with residual mean displacement of 3.9 mm (range: 0.5-9.0 mm). Multivariable analysis demonstrated a positive association between age (p = 0.04) and initial displacement (p = 0.04) on the final degree of residual displacement at union. A Kaplan-Meier survival analysis identified increased age to be significantly related to increased time to union (X2 (2) = 21.034, p < 0.001).

CONCLUSIONS

Union rates following percutaneous screw fixation of superior pubic rami fractures associated with lateral compression-type pelvic ring injuries approach 95%. Though minimal in an absolute sense, increasing age and a greater degree of initial displacement may influence the final degree of residual displacement at union.

LEVEL OF EVIDENCE

IV.

Use of the iliac-outlet and iliac-inlet combined views in percutaneous posterior column retrograde screw fixation

Posterior column fractures are common acetabular injuries. Although displaced fractures require open reduction and fixation, undisplaced patterns may benefit from percutaneous screw fixation. The combination of iliac oblique with inlet and outlet views offers an intuitive and panoramic rendering of the bony corridor into the posterior column; lateral cross table view completes the sequence of fluoroscopic projections. Herein we describe the use of outlet/inlet iliac views and a detailed procedure for percutaneous retrograde posterior column screw fixation.

Standard practice in the treatment of unstable pelvic ring injuries: an international survey

PURPOSE

Unstable pelvic ring injury can result in a life-threatening situation and lead to long-term disability. Established classification systems, recently emerged resuscitative and treatment options as well as techniques, have facilitated expansion in how these injuries can be studied and managed. This study aims to access practice variation in the management of unstable pelvic injuries around the globe.

METHODS

A standardized questionnaire including 15 questions was developed by experts from the SICOT trauma committee (Société Internationale de Chirurgie Orthopédique et de Traumatologie) and then distributed among members. The survey was conducted online for one month in 2022 with 358 trauma surgeons, encompassing responses from 80 countries (experience > 5 years = 79%). Topics in the questionnaire included surgical and interventional treatment strategies, classification, staging/reconstruction procedures, and preoperative imaging. Answer options for treatment strategies were ranked on a 4-point rating scale with following options: (1) always (A), (2) often (O), (3) seldom (S), and (4) never (N). Stratification was performed according to geographic regions (continents).

RESULTS

The Young and Burgess (52%) and Tile/AO (47%) classification systems were commonly used. Preoperative three-dimensional (3D) computed tomography (CT) scans were utilized by 93% of respondents. Rescue screws (RS), C-clamps (CC), angioembolization (AE), and pelvic packing (PP) were observed to be rarely implemented in practice (A + O: RS = 24%, CC = 25%, AE = 21%, PP = 25%). External fixation was the most common method temporized fixation (A + O = 71%). Percutaneous screw fixation was the most common definitive fixation technique (A + O = 57%). In contrast, 3D navigation techniques were rarely utilized (A + O = 15%). Most standards in treatment of unstable pelvic ring injuries are implemented equally across the globe. The greatest differences were observed in augmented techniques to bleeding control, such as angioembolization and REBOA, more commonly used in Europe (both), North America (both), and Oceania (only angioembolization).

CONCLUSION

The Young-Burgess and Tile/AO classifications are used approximately equally across the world. Initial non-invasive stabilization with binders and temporary external fixation are commonly utilized, while specific haemorrhage control techniques such as pelvic packing and angioembolization are rarely and REBOA almost never considered. The substantial regional differences' impact on outcomes needs to be further explored.

Trends in non-operative management of low-energy pelvic fracture: An analysis of the Nationwide Inpatient Sample

Introduction

Non-operative management is common for low-impact pelvic fractures. In this study, we characterize the epidemiology of those treated nonoperatively following low-energy pelvic fracture, while identifying recent management trends.

Methodology

Data from the Nationwide Inpatient Sample (NIS) database from 2011 to 2018 were analyzed. We identified adult patients diagnosed with pelvic fracture based on International Classification of Diseases (ICD) codes, excluding fractures of the acetabulum, femur, polytrauma, and open fractures to isolate cases caused by low-impact mechanisms. Codes indicating operative management were excluded. Demographic information and outcomes (length of stay, in-hospital mortality, hospital discharge status) were collected. Sub-analyses were performed to identify trends.

Findings

123,936 eligible patients were identified. The average age was 68.7 years. 70% were female, showing a decline from 75% to 66% over the study period. Pubic bone involvement was observed in 59% of fractures. The mean Charlson Comorbidity Index (CCI) was 3.83, corresponding to a 10-year survival rate of 58.5%, which remained relatively stable throughout the study period. 62.4% of patients received treatment at urban teaching hospitals. Average length of hospital stay was 6.3 days. Discharge to a skilled nursing facility (SNF) was the most common outcome, ranging from 62.1% to 65.0% during the study period, while 20.0% of patients were discharged home (18.4%-21.1%). Mean in-hospital mortality was 3.28%, showing no significant change, with higher rates among male patients (5.1%) and patients of Asian descent (3.8%).

Conclusion

The majority of patients receiving nonoperative treatment for low-energy pelvic fractures were females in their mid-60s with moderate comorbidity. The study reveals a relatively high in-hospital mortality rate of 3.28%, particularly among male patients and those of Asian descent, indicating the need for increased surveillance for further injury in these groups. Most patients were discharged to a SNF, highlighting the necessity for extended rehabilitation in this population. This persistent trend is noteworthy considering the growing emphasis on the cost of inpatient admissions and advancements in outpatient management of orthopedic injuries.

The radiographic outcome after plating for pubic symphysis diastasis: does it matter clinically?

INTRODUCTION

Open reduction and internal fixation with plates is the most widespread surgery in traumatic pubic symphysis diastasis. However, implant failure or recurrent diastasis was commonly observed during follow-up. The aim of our study was to evaluate the radiologic findings and clinical outcomes.

MATERIALS AND METHODS

Sixty-five patients with traumatic pubic symphysis diastasis treated with plating between 2008 and 2019 were retrospectively reviewed. The exclusion criteria were a history of malignancy and age under 20 years. Radiographic outcomes were determined by radiograph findings, including pubic symphysis distance (PSD) and implant failure. Clinical outcomes were assessed according to the Majeed score at the final follow-up.

RESULTS

Twenty-eight patients were finally included. Nine patients (32%) experienced implant failure, including four (14%) with screw loosening and five (18%) with plate breakage. Only one patient underwent revision surgery. Postoperatively, a significant increase in PSD was observed at 3 months and 6 months. Postoperative PSD was not significantly different between patients with single plating and double plating, but it was significantly greater in the implant-failure group than in the non-failure group. The Majeed score was similar between patients with single plating and double plating or between the implant-failure group and the non-failure group. Body mass index, number of plates, age, and initial injured PSD were not significantly different between the implant-failure group and the non-failure group. Only a significant male predominance was observed in the implant-failure group.

CONCLUSION

A gradual increase in the symphysis distance and a high possibility of implant failure may be the distinguishing features of traumatic pubic symphysis diastasis fixation. The postoperative symphyseal distance achieved stability after 6 months, even after implant failure. Radiographic outcomes, such as increased symphysis distance, screw loosening, and plate breakage, did not affect clinical functional outcomes.

A cadaveric biomechanical evaluation of anterior posterior compression II injuries

PURPOSE

Pelvic fractures are associated with high morbidity and often require surgical intervention. An Anterior Posterior Compression (APC) II injury consists of disruption at the pubic symphysis and anterior sacroiliac joint. Studies investigating specific ligamentous contributions would aid in development of novel fixation techniques. The objective of this study is to determine the level of pelvic destabilization from progressive soft tissue disruptions associated with APC II injuries.

METHODS

Six fresh-frozen cadaveric pelvises were dissected of soft tissues, preserving joint capsules and ligaments. Each pelvis was secured in a double-leg stance and joint motion was tracked with the specimens cyclically loaded to 60% body weight. Each specimen was measured in the intact state and again following stepwise destabilization to an APC II injury model (PS: sectioned pubic symphysis, IPS JOINT: PS + ipsilateral anterior sacroiliac, sacrotuberous, sacrospinous ligaments sectioned, IPS LIGS: IPS JOINT + ipsilateral interosseous ligaments sectioned, IPS JOINT+CONT ASI: IPS LIGS + contralateral anterior sacroiliac ligament disruption).

RESULTS

Compared to the intact state, there was a statistically significant increase in movement in the IPS JOINT (ipsilateral 177%, p<0.001; contralateral 46%, p<0.005) and IPS JOINT+CONT ASI (ipsilateral 184%, p<0.002; and contralateral 62%, p<0.002) states bilaterally. No significant change was demonstrated in the PS or IPS LIGS state.

CONCLUSION

Disruption of ipsilateral ligamentous structures destabilized both sacroiliac joints. The interosseous and posterior sacroiliac ligaments provide the majority of stability of the sacroiliac joint and will likely benefit most from surgical stabilization.

LEVEL OF EVIDENCE

mechanism-based reasoning.

Use of calcaneal plates in the treatment of posterior pelvic ring injuries and displaced iliac blade fractures- A case series

Introduction

The operative fixation of pelvic ring injuries and associated acetabulum fractures presents a challenging scenario to most of the orthopaedic trauma surgeons. Current development of anatomically contoured reconstruction (ACR) plates gained popularity in fixing complex pelvic ring fractures. This study was done to assess the functional and radiological outcomes using of lateral wall stainless steel (LWSS) calcaneal plates in posterior pelvic ring injuries and displaced iliac blade fractures.

Materials and methods

Retrospectively selected eight cases of pelvic ring injuries planned for fixing posterior pelvic instability and iliac blade fractures using LWSS plates. Mean follow-up was 18 months (Range 12-26 months).

Results

Average time for radiological bony union achieved in 18 weeks (Range 13-22). Seven patients returned to their normal work. Average Majeed score was 60 (Range 50-68). Mean duration of surgery was 160 min (Range 120-200).

Conclusion

This technique can be routinely used as supplementary fixation for posterior pelvic ring instability and iliac blade fractures. LWSS calcaneal plates showed no screw breakage or implant failure. Further this technique was cost effective in developing countries with limited resources.

Sacroiliac screws fixation navigated with three-dimensional printing personalized guide template for the treatment of posterior pelvic ring injury: A case report

Objective

Pelvic injuries refer to the disruption of the inherent structural and mechanical integrity of the pelvic ring. Sacroiliac screw fixation technique is often used for the treatment of posterior pelvic ring injury, which is prone to the iatrogenic injury. Various attempts were proposed to avoid iatrogenic injuries, while the executing processes are usually too cumbersome. The patient-personalized guide template based on 3D printing technology has been considered as a promising method, which can achieve lower deviation and higher accuracy in a simple and convenient way. We reported the first case of posterior pelvic ring injury using 3D printing personalized guide template with the verification of intraoperative CT.

Methods

The subject was a 74-year-old female with posterior pelvic ring injury. Two patient-specific guide templates were customized based on 3D printing technology, one for S1 and the other for S2. We used the guide templates for navigation to place the sacroiliac screws. The placement of screws was verified by intraoperative CT. Intraoperative and postoperative variables were collected.

Results

The technique helped us successfully insert the sacroiliac screws into the safe zone. The intraoperative blood loss was 23.03 ml, and the duration of operation was 62 min. The exposure dose during CT scanning was 7.025 mSv. The assessment of screws position was excellent. Furthermore, there was no sign of any functional impairment postoperatively.

Conclusion

Sacroiliac screws fixation with the assistance of 3D printing personalized guide template under the verification of intraoperative CT may be a promising method to treat posterior pelvic ring injuries.

Crescent Fracture of the Pelvis: A Case Report

Crescent fractures are a rare type of pelvic injury. They result from a lateral compression force and are rotationally unstable. The following is a case of a young male who suffered a crescent fracture on the right side of the pelvis and was treated for the same. These fractures, being rare and complex, need to be managed in accordance with other injuries sustained by the patient and also need fixation for a better functional outcome.

Lumbopelvic Fixation with Bridged Distal Iliac Screws for Vertically Unstable Sacral Fractures

Purpose

The purpose of this study is to evaluate preliminary outcomes of vertically unstable sacral fractures treated by lumbopelvic fixation (LPF) augmented transiliac bridged screws.

Methods

From April 2017 to December 2019, fifteen consecutive patients with vertically unstable sacral fractures who had undergone LPF augmented transiliac bridged screws were enrolled. The radiological assessment included standard lumbopelvic x-rays and pelvic computed tomography (CT) to evaluate the lumbosacral angle (LSA), sacral kyphosis angle (SKA), lumbar lordosis angles (LLA) and Matta's reduction criterias (MRC). Clinical and neurologic impairment outcomes were evaluated by the Majeed grading scale (MGS) and Gibbons criterias, respectively.

Results

All patients were followed for an average of 18 months (range, 14-25). All sacral fractures eventually healed and implant failure did not occur in any patient, though there were two patients with a loss of reduction (< 5 mm) during the follow-up period. According to the MRC, the results were excellent on 14 sides, good on five sides, and fair on one side. The MGS mean score was 82 points (range, 49-98 points); the results were excellent in nine cases, good in four cases, and fair in two cases. There was no statistically significant difference in SKA and LLA in preoperative and postoperative final controls. The preoperative and postoperative LSA were 72 ± 13.9 and 44.1 ± 11.3, respectively, and a statistically significant improvement was observed (p = 0.01).

Conclusion

In vertically unstable sacrum fractures, we believe that LPF augmented with transiliac bridging technique may expedite the reduction of vertical sacrum fracture and offers a reinforced fixation choice.

Symptomatic Ischial Stress Fractures in Elite Athletes Treated With Percutaneous Screws: A Report of 2 Cases

CASES

Two high-level athletes with symptomatic gluteal pain with explosive movements that had failed nonoperative management were eventually diagnosed with ischial stress fractures. These were treated with percutaneous posterior column screws. Both patients healed their fractures and made full return to sport.

CONCLUSION

Ischial stress fractures should be considered in the differential for athletes with persistent gluteal pain. Percutaneous fixation is a minimally invasive and effective method of treating symptomatic ischial stress fractures that have failed nonoperative treatment.

Bilateral pelvic crescent fracture combined with left acetabular fracture: A case report

Introduction

Presentation of case

Conclusion

•

Bilateral crescent fracture is a rare entity of the pelvic ring injury and is usually secondary to high-velocity impact.

•

Only 3 cases of bilateral crescent fracture were reported in the litterateur but not with acetabulum fracture.

•

Initial management of such injury consists of hemodynamic stabilization of the patient and afterword the injury can be addressed.

•

No standard of treatment is been described yet, but staged surgical stabilization of such combined fractures is recommended which affect the outcome.

Percutaneous posterior transiliac plate versus iliosacral screw fixation for posterior fixation of Tile C-type pelvic fractures: a retrospective comparative study

BACKGROUND

This study aimed to compare the clinical outcomes and complications between two minimally invasive surgical techniques: percutaneous transiliac plate fixation and iliosacral (IS) screw fixation for the treatment of Tile C-type pelvic bone fractures.

METHODS

We retrospectively reviewed the data of 77 consecutive patients with Tile C pelvic ring injuries who underwent either percutaneous transiliac plate fixation or IS screw fixation in a single academic center between November 2007 and January 2018. We recorded patients' demographics, surgery-related data, and postoperative surgical outcomes and compared the incidence of complications and revision surgery rates between the two groups.

RESULTS

Overall, 14 patients were included in the plate group, while 63 were included in the IS screw fixation group. No significant differences were observed in the patients' demographics between the two groups except for a longer interval from injury to surgery (13.5 days vs. 5.4 days, P = 0.001). Both groups acquired fracture union in all cases. There was one case of infection requiring surgical debridement in the plating group. Notably, nerve injury (n = 3) and implant loosening (n = 5) occurred in the IS screw group, but the difference was not significant.

CONCLUSIONS

Both percutaneous posterior transiliac plating and IS screw fixation in patients with Tile C-type pelvic bone fractures showed good results. We recommend IS screw fixation as the primary treatment and propose posterior plating as treatment for sacral dysmorphism and bilateral sacral alar fractures in patients with spinopelvic dissociation.

LEVEL OF EVIDENCE

III.

A novel technique for stabilising sacroiliac joint dislocation using spinal instrumentation: technical notes and clinical outcomes

Purpose

Currently, sacroiliac joint dislocations, including crescent fracture–dislocations, are treated using several techniques that have certain issues. We present the technical details and clinical outcomes of a new technique, anterior sacroiliac stabilisation (ASIS), performed using spinal instrumentation.

Methods

ASIS is performed with the patient in a supine position via the ilioinguinal approach. The displacements are reduced and fixed by inserting cancellous screws from the sacral ala and iliac brim; the screw heads are bridged using a rod and locked. We performed a retrospective review of patients with iliosacral disruption who underwent ASIS between May 2012 and December 2020 at two medical facilities. The patients were assessed for age, sex, injury type, associated injuries, complications, functional outcome by evaluating the Majeed pelvic score after excluding the sexual intercourse score and fracture union.

Results

We enrolled 11 patients (median age: 63 years). The median operative time was 195 min, median blood loss was 570 g, and eight patients (72.3%) required blood transfusion. The sacral and iliac screws had a diameter of 6.0–8.0 mm and 6.2–8.0 mm, and a length of 50–70 mm and 40–80 mm, respectively. Bone union was achieved with no marked loss of reduction in the median follow-up period of 12 months in all cases. The median Majeed score at the final follow-up was 85/96.

Conclusion

ASIS is a rigid internal fixation method that provides angular stability. Despite invasiveness issues compared to iliosacral screw fixation, this method is easy to confirm and achieves precise reduction.

Treatment of unstable pelvic ring injury with a dual internal anterior subcutaneous fixator using spinal instrumentation called "dual INFIX": A case report

Introduction

External fixation, various subcutaneous screw fixations, and plate fixation can be considered as fixation methods for unstable pelvic ring fractures. We describe a first case of treated unstable pelvic ring injury using a dual internal anterior subcutaneous fixator we called "dual INFIX," comprising four screws, two subcutaneous rods, and two cross-link connectors, without posterior fixation.

Case Report

An 81-year-old man sustained an unstable pelvic injury (AO type B2) with fracture of the left ilium and pubis. Dual INFIX was used to stabilize the pelvic ring injury. Polyaxial screws were introduced along a path between the anterior inferior iliac spine and ipsilateral posterior superior iliac spine until the head of the screw lay immediately above the fascia. Bilateral cranial screws were connected by a rod passed subcutaneously, and caudal screws were connected by the other rod. Finally, cross-link connectors connected cranial and caudal rods on the right and left. One year after the first operation, the patient could walk without a cane and had no limitation of daily living and bony fusion was achieved.

Conclusion

The stability of the pelvic ring of dual INFIX was sufficient to achieve bony fusion in this case. The stability of dual INFIX should be stronger than that of INFIX. Dual INFIX as with INFIX has other advantages such as ease of management compared with external fixation, and nonnecessity of strict anatomical reduction compared with various percutaneous screw fixation. Furthermore, this technique is simple and minimally invasive compared with plate fixation because it does not require open surgery. However, because the type C fracture with an unacceptable position of reduction by closed reduction has the possibility to become a symptomatic malunion, such cases should not be treated by this method. Furthermore, it is necessary for pelvic stabilization using dual INFIX that the contralateral pelvis is intact because dual INFIX stabilizes the fracture side with the other side of the pelvis. Dual INFIX can be considered as an option of fixation methods for type B-1 or 2 pelvic ring injuries.

Comparison of lumbopelvic fixation and iliosacral screw fixation for the treatment of bilateral sacral fractures

Background

Bilateral sacral fractures result in traumatic disruption of the posterior pelvic ring. Treatment for unstable posterior pelvic ring fractures should aim for fracture reduction and rigid fixation to facilitate early mobilization. Iliosacral screw fixation (ISF) and lumbopelvic fixation (LPF) were recommended for the treatment of these injuries. No algorithm or gold standard exists for surgery of these fractures.

Purpose

The purpose of this study was to evaluate the differences between ISF and LPF in bilateral sacral fractures regarding intraoperative procedures, complications and postoperative mobilization. The secondary aim was to determine whether demographics influence surgical treatment.

Methods

Over a 4-year period (2016–2019), 188 consecutive patients with pelvic ring injuries were treated at one academic level 1 trauma center and retrospectively identified. Fractures were classified according to the AO/OTA classification system. Seventy-seven patients were treated with LPF or ISF in combination with internal fixation of pubic rami fractures and could be included in this study. Comparisons were made between demographic and perioperative data. Infection, hematoma and hardware malpositioning were used as complication variables. Mobilization with unrestricted weight bearing was used as outcome variable. Follow-up was at least 6 months postoperatively.

Results

Operative stabilization of bilateral posterior pelvic ring injuries was performed in 77 patients. Therefore, 29 patients (females 59%) underwent LPF whereas 48 patients (females 83%) had bilateral ISF. The ISF group was older (76 yrs.) compared to the LPF group (62 yrs.) (p = 0.001), but no differences regarding BMI or comorbidities were detected. Time for surgery was reduced for patients who were treated with ISF compared to lumbopelvic fixation (73 min vs. 165 min; respectively, p < 0.001). But this did not result in reduced fluoroscopic time or radiation exposure. Overall complication rate was not different between the groups. Patients with LPF had a greater length of stay (p = 0.008) but were all weight bearing as tolerated when discharged (p < 0.001).

Conclusion

Bilateral posterior pelvic ring injuries of the sacrum can be sufficiently treated by LPF or ISF. LPF allows immediate weight bearing which may benefit younger patients and patients with an elevated risk for pneumonia or other pulmonary complications. Treatment with ISF reduces operative time, length of stay and postoperative wound infection. Elderly patients may be better suited for treatment with ISF if there is concern that the patient may not tolerate the increased operative time.

Anatomical Considerations in Percutaneous Fixation of the Pelvis and Acetabulum

Reduction and fixation techniques of the pelvis and acetabulum continue to evolve. There has been increased use of percutaneous and minimally invasive techniques in the past several decades. Although offering many advantages to traditional open techniques, percutaneous techniques still place nearby structures at risk, making a thorough understanding of the applied surgical anatomy essential.

Low Superior Pubic Ramus Screw Failure Rate With Combined Anterior and Posterior Pelvic Ring Fixation

OBJECTIVES

To determine whether fracture pattern, implant size, fixation direction, or the amount of posterior pelvic ring fixation influences superior ramus medullary screw fixation failure.

DESIGN

Retrospective cohort review.

SETTING

Regional Level 1 trauma center.

PATIENTS/PARTICIPANTS

After exclusion criteria, 95 patients with 111 superior ramus fractures with 3 months minimum follow-up were included.

INTERVENTION

All patients underwent anterior and posterior pelvic ring fixation.

MAIN OUTCOME MEASUREMENTS

Comparison of immediate postoperative radiographs and/or computer tomography scan with the latest postoperative image to calculate interval fracture displacement and implant position. Postoperative fracture displacement or implant position change greater than 1 cm were considered fixation failures.

RESULTS

Five screws were defined as failures (4.5%), including 3 retrograde, 3 with bicortical fixation, 4 with a 4.5-mm screw, and 1 with a 7.0-mm screw. Fracture patterns included 2 oblique and 3 comminuted fractures. Based on the Nakatani classification, there were 3 zone II, 1 zone I, and 1 zone III. Failure modes included 3 with cut-out along the screw head and 1 cut-out and 1 cut-through at the screw tip.

CONCLUSIONS

Our incidence of superior pubic ramus intramedullary screw fixation failure was 4.5%. Even with anterior and posterior fixation along with precise technique, failures still occur without a common failure predictor. The percutaneous advantages and proven strength provided by an intramedullary implant make it desirable to help reestablish global pelvic ring stability. Biomechanical and clinical studies are needed to further understand intramedullary superior ramus screw fixation.

LEVEL OF EVIDENCE

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

[Triangular minimally invasive spinopelvic stabilization for type C pelvic fractures according to AO/OTA and type IV according to FFP]

INTRODUCTION

Spinopelvic instability is common in type IV fragility fractures of the pelvic ring (FFP) and type C traumatic pelvic fractures. This results in the indications for operative stabilization using a spinopelvic support. Due to the variety of surgical techniques for spinopelvic support it is unclear what importance a minimally invasive spinopelvic screw-rod osteosynthesis can have.

MATERIAL AND METHODS

In the retrospective clinical study over a period of 2 years, 23 patients (median age 67 years, 5 male and 18 female) with unstable pelvic fractures (FFP type IV: n = 12, AO/OTA type C: n = 11) treated by triangular minimally invasive spinopelvic stabilization (TMSS) were included in the study. The patient data were examined with respect to the parameters gender, age, fracture morphology, intraoperative blood loss, operating time, postoperative infection, postoperative reduction result in the computed tomography (CT) imaging and screw loosening.

RESULTS

The average age of the 11 type C fractures was 43 years and that of the 12 FFP type IV fractures was 80 years. The follow-up period was on average 12.2 months. The average operation time was 67 min, the blood loss was 70 ml, there were 2 postoperative infections and 4 cases of screw loosening. The reduction according to Matta was < 4 mm for all FFP and between 4-20 mm for traumatic pelvic fractures. Symptomatic pseudarthroses occurred in 3 cases.

CONCLUSION

The triangular minimally invasive spinopelvic stabilization (TMSS) showed a stable and sufficient treatment of the type IV fragility fractures and in the slightly displaced type C traumatic pelvic fractures. Coarse fracture dislocations limit the procedure.

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

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

An experimental study on the safe placement of sacroiliac screws using a 3D printing navigation module

Background

In this experimental study, we evaluated the use of digital 3D navigation printing in minimizing complications arising from sacroiliac screw misplacement.

Methods

A total of 13 adult pelvic specimens were studied using 3D navigation printing. Mimics software was used for preoperative planning and for obtaining sacrum median sagittal resection and long axis resection of the S1 pedicle center by 3D segmentation. The ideal screw path had its origin at the post-median part of the auricular surface of the sacroiliac joint, the midpoint at the mid-position of the lateral recess and outlet of the anterior sacral foramina; and the endpoint at the S1 sagittal resection. A sacroiliac screw fixed the pelvic specimens with the assistance of the navigation module. The distance between the start point (ilium surface) and endpoint (sacral median sagittal resection) of the screw path was measured after the pre- and postoperative 3D pelvis module was 3D-registered according to the standard precision range. The origin/endpoint qualified rates of the postoperative (n/26) and preoperative (26/26) screw paths were analyzed by the chi-square test.

Results

No screw misplacement occurred in the screw paths of any of the 13 pelvic specimens. The mean distance between the preoperative and postoperative origin of the screw path was 1.5415±0.6806 mm, and the mean distance between the preoperative and postoperative endpoint was 2.2809±0.4855 mm. The qualified rate of origin was 23/26 when the precision grade was 2.4 mm (P>0.05, χ²=1.41), while the qualified rate of endpoint was 21/26 when the precision grade was 2.7 mm (P>0.05, χ²=3.54).

Conclusions

In this experimental study, using a 3D printing navigation module helped attain an accurate and safe sacroiliac screw implantation.

Antegrade anterior column screw placement in the lateral decubitus position utilizing an axial view: a technical trick

The placement of anterior column screws is a useful procedure and has standard views when placing this screw in the supine position. Feng et al. described an acetabular anterior column axial view for patients in the supine position for a placement of a retrograde anterior column screw [J Orthop Surg (Hong Kong) 25, 2309499016685012]. However, many acetabular fracture surgeries are performed in the lateral decubitus position due to a variety of reasons. Placing an antegrade anterior column screw in this position is difficult due to an unfamiliarity of the optimal fluoroscopic images. The purpose of this article is to describe a novel technique to obtain appropriate imaging to safely place an anterior column screw while the patient is in the lateral decubitus position.

Posterior wall fractures associated with both-column acetabular fractures can be skilfully ignored

INTRODUCTION

Posterior wall fractures may be associated with both-column acetabular fractures. Considering the differences in the pattern of these fractures in contrast to isolated posterior wall fractures, it is currently unclear whether they can be ignored or need to be addressed surgically.

HYPOTHESIS

Stable posterior wall fractures can be skilfully ignored in patients with both-column acetabular fractures operated by an ilioinguinal approach.

MATERIAL AND METHODS

We retrospectively reviewed 49 consecutive patients who were treated for both-column acetabular fractures between the years 2009 and 2018. Considering the association of posterior wall fractures, we divided the cohort into two groups: Group 1 (n=29): absence of posterior wall fractures; and Group 2 (n=20): presence of posterior wall fractures, subsequently treated while skilfully ignoring stable posterior wall fracture according to our criteria. Intergroup comparison of radiologic and clinical outcomes and multiple linear regression for predictors of clinical outcomes were analysed.

RESULTS

No significant intergroup difference in quality of reduction, post-traumatic osteoarthritis grade, or clinical outcome was noted. Poor post-traumatic osteoarthritis grade and poor quality of reduction of both acetabular columns were significant predictors of clinical outcomes in patients with both-column acetabular fractures. Whether posterior wall fracture was associated and skilfully ignored was unrelated to clinical outcomes.

DISCUSSION

Posterior wall fractures associated with both-column acetabular fractures can be successfully ignored if the posterior wall fragment is adequately attached to the acetabulum through the labrocapsular complex of the hip joint, and the hip-joint-congruency in the presence of<2-mm step-off and 3-mm gap.

LEVEL OF PROOF

III, prognostic.

Amid COVID-19 pandemic-an innovative use of local resources to substitute the need for specialized operation theatre tables for orthopaedic and trauma surgery

Pelvic-acetabulum and spine surgery are two important constituents of complex trauma surgery and require a gamut of resources for fracture management. In the pandemic crisis of COVID-19 where existing health care resources are scarce and a major section of health care infrastructure has been assigned to fight against it, the compromised and less equipped health care facility is left to tackle the ongoing presentation of complex trauma surgery. One major challenge faced to manage these complex procedures is the availability of specialized radiolucent operation tables as even the apex level health care setups generally have one or two such kinds of table. Therefore, in this state of pandemic crisis, innovations utilizing the available local resources need to be developed to avoid deferring these complex operations.

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

INTRODUCTION

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

PATIENT AND METHODS

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

RESULTS

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

DISCUSSION AND CONCLUSION

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

Interdigitating percutaneous screw fixation for Rommens type IIIa fragility fractures of the pelvis: technical notes and preliminary clinical results

PURPOSE

Fragility fractures of the pelvis (FFPs) type IIIa in the Rommens classification include unilateral iliac fractures as well as pubic rami fractures. We devised a new, less-invasive fixation technique to achieve increased stability for FFPs type IIIa. The aim of this study was to describe this procedure and report the preliminary clinical results.

METHODS

A total of 14 geriatric patients (> 60 years old) who sustained FFP type IIIa caused by low-energy trauma were surgically treated with interdigitating screw fixation including a trans-pubic screw in a retrograde manner and two trans-iliac screws from the anterior inferior iliac spine toward the posterior inferior iliac spine. All iliac fractures were displaced with external rotation, and closed reduction was performed. Percutaneous screw fixation, in which fully threaded screws were in contact with each other, provided stable fixation allowing early mobilization.

RESULTS

A median decrease in pain levels by post-operative day two was 4.5 compared with pre-operatively using a numerical rating scale. While full weight-bearing was allowed from four weeks post-operatively in the initial five patients, immediate full weight-bearing was instructed as tolerated for the subsequent nine patients. No complications were encountered during the peri-operative period. At the final follow-up, all fractures were united without fixation loss, screw dislodgment, or hardware failure.

CONCLUSIONS

This procedure of closed reduction and interdigitating screw fixation for FFP type IIIa appears to represent a safe, reliable technique. Our experience suggests that interdigitating fixation for FFP type IIIa is effective for relieving pain and promoting early mobilization in elderly patients.

Ischial tuberosity avulsion fracture nonunions in the adolescent population treated with a posterior column screw: A case series of two patients

Various surgical techniques exist to approach an ischial tuberosity avulsion fracture, including open reduction and internal fixation with screws and suture anchors, augmentation with allograft tendon, and excision of the fragment. However, the majority of these techniques approached acute fractures, and nonunions were not addressed nor studied. This case series describes two adolescent patients treated for ischial tuberosity nonunions with a posterior column screw through a subgluteal approach. Both patients demonstrated radiographic healing of their nonunion sites at 6 months' follow-up. Each patient reported no pain during activity, had symmetric hamstring strength, and were able to return to pre-injury level of activity by final follow-up. In conclusion, the authors utilized a muscle-sparing approach to the ischial tuberosity nonunion site through a cosmetically appealing incision and introduced a novel approach to nonunion fixation without the use of bone graft, resulting in excellent clinical outcomes.

Results of open reduction internal fixation versus percutaneous iliosacral screw fixation for unstable pelvic ring injuries: retrospective study of 36 patients

INTRODUCTION

Surgical stabilization of posterior pelvic ring fractures can be achieved by closed reduction and percutaneous fixation (CRPF) or by open reduction and internal fixation (ORIF). The aim of the present study is to compare the clinical results of both methods.

MATERIAL AND METHODS

Medical records of 36 patients consecutively operated for unstable pelvic ring injuries were retrospectively reviewed. We compared 22 patients treated with CRPF versus 14 patients stabilized by using ORIF between 2007 and 2017. The Majeed and Pohlemann scores were used to evaluate postoperative functional outcomes. Complications like blood loss, infection rate, Neurological injury, the operative time and the length of hospital stay were analyzed.

RESULTS

The median Majeed pelvic score was 87 points for the CRPF technique compared with 69 points for the ORIF technique. The median Pohlemann score, operative time and length of hospitalization were similar between the two groups. The median blood loss for the CRPF technique was 300 ml compared to 500 ml for the ORIF technique. CRPF and ORIF procedure had each one neurological lesion. There was one case of infection in the ORIF group and none in the CRPF group. No measurements except for the blood loss have reached the significance threshold.

CONCLUSION

The CRPF technique shows a clear decrease in blood loss. There was no statistically significant difference in the functional results, infection rate, neurological injury, operative time and hospital stay between both techniques.

Comparison of Biomechanical Performance of Five Different Treatment Approaches for Fixing Posterior Pelvic Ring Injury

Background

A large number of pelvic injuries are seriously unstable, with mortality rates reaching 19%. Approximately 60% of pelvic injuries are related to the posterior pelvic ring. However, the selection of a fixation method for a posterior pelvic ring injury remains a challenging problem for orthopedic surgeons. The aim of the present study is to investigate the biomechanical performance of five different fixation approaches for posterior pelvic ring injury and thus provide guidance on the choice of treatment approach in a clinical setting.

Methods

A finite element (FE) model, including the L3-L5 lumbar vertebrae, sacrum, and full pelvis, was created from CT images of a healthy adult. Tile B and Tile C types of pelvic fractures were created in the model. Five different fixation methods for fixing the posterior ring injury (PRI) were simulated: TA1 (conservative treatment), TA2 (S1 screw fixation), TA3 (S1 + S2 screw fixation), TA4 (plate fixation), and TA5 (modified triangular osteosynthesis). Based on the fixation status (fixed or nonfixed) of the anterior ring and the fixation method for PRI, 20 different FE models were created. An upright standing loading scenario was simulated, and the resultant displacements at the sacroiliac joint were compared between different models.

Results

When TA5 was applied, the resultant displacements at the sacroiliac joint were the smallest (1.5 mm, 1.6 mm, 1.6 mm, and 1.7 mm) for all the injury cases. The displacements induced by TA3 and TA2 were similar to those induced by TA5. TA4 led to larger displacements at the sacroiliac joint (2.3 mm, 2.4 mm, 4.8 mm, and 4.9 mm), and TA1 was the worst case (3.1 mm, 3.2 mm, 6.3 mm, and 6.5 mm).

Conclusions

The best internal fixation method for PRI is the triangular osteosynthesis approach (TA5), followed by S1 + S2 screw fixation (TA3), S1 screw fixation (TA2), and plate fixation (TA4).

Biomechanical comparison of minimally invasive treatment options for Type C unstable fractures of the pelvic ring

BACKGROUND

The definite treatment of pelvic C fractures presents a widely discussed issue and undergoes continuous evolution. While the stabilization of the posterior ring has been studied extensively, the fixation of the anterior pelvic ring continuous to be rarely investigated. The importance of the simultaneous stabilization however lays in the earlier mobilization and prevention of long-term damage to the pelvis. Therefore we investigated four combinations of minimally invasive fixation techniques for unstable type C1-3 pelvic injuries and aimed to answer the following research questions: (1) what combination of fixation methods yields the highest stiffness and the least displacement? (2) Is the combination of a single sacroiliac screw (SI-screw) with a transiliac internal fixator (TIFI) a reasonable alternative to two SI-screws? (3) Is a modified unilateral anterior fixation comparable to a retrograde transpubic screw?

HYPOTHESIS

Minimally invasive fixation techniques provide sufficient biomechanical stability for type C pelvic fractures.

METHODS

Thirty synthetic full pelvises were divided into 5 groups, of which 4 groups were assigned a different osteosynthesis method and one was an intact pelvis used as reference (group 1: internal fixator+2 sacroiliac screws, group 2: internal fixator+transiliac internal fixator+1 sacroiliac screw, group 3: retrograde transpubic screw+2 sacroiliac screws, group 4: retrograde transpubic screw+transiliac internal fixator+1 sacroiliac screw). The pelvises underwent a protocol of cyclic loading between 100N and 200N, during which they were subjected to compression loads while the position of the fracture fragments was measured every 30 milliseconds. Displacement and stiffness were calculated for statistical analysis.

RESULTS

The minimally invasive fixation methods investigated in this study all provide sufficient biomechanical stability without one method being superior to the others (p [anterior displacement]=0.61 and p [posterior displacement]=0.88). Group 3 was allowed the least displacement (1.8±0.2mm for anterior and posterior fracture) for the treatment of a C1.3 fracture. The other fixation methods displayed the following dislocations (mm) of the anterior pelvic ring: group 1: 1.9±0.3, group 2: 2.1±0.4, group 4: 2.0±0.5. Posteriorly, the displacements (mm) were the following: group 1: 1.8±0.6, group 2: 1.9±0.2, group 4: 2.0±0.5.

DISCUSSION

The minimally invasive fixation methods investigated in this study all provide sufficient biomechanical stability without one method being superior to the others since differences were not significant regarding anterior and posterior displacements. Even if not significantly, we could reveal that out of all the methods tested the combination of 2 SI-screws with a retrograde transpubic screw (group 3) displayed the least displacement and highest stiffness. These techniques could therefore potentially improve patient's clinical outcome by reducing the surgical invasiveness and procedure time while providing sufficient biomechanical stability.

LEVEL OF EVIDENCE

III, comparative in vitro study.

Outcomes following pelvic ring fractures in the paediatric population: A systematic review

BACKGROUND

Pelvic fractures represent a small proportion of all paediatric fractures, but are likely to be associated with a high-energy mechanism, multiple injuries, and significant morbidity and mortality. Operative fixation of unstable pelvic fractures is accepted. However, there remains a paucity of data on functional outcomes and complications following pelvic fractures in the skeletally immature.

METHODS

A PRISMA-compliant systematic review was performed, searching Medline, Embase, and Cochrane central review. The primary outcome was functional outcome after pelvic fractures in the paediatric population following operative or non-operative treatment. Secondary outcomes included mechanism of injury, associated injuries, mortality rate, and method of surgical fixation if required. Where possible, weighted totals of the data set were performed.

RESULTS

In total, 23 studies were included in this review. Only eight studies reported functional outcomes, with limb length discrepancy and limp being the most common complication. Only 8.8% of all pelvic fractures underwent surgical fixation. Motor vehicle collision was the most common cause of injury, and extremity fracture was the most common associated injury.

CONCLUSION

Paediatric pelvic fractures are caused by high-energy mechanisms and have significant morbidity and mortality. There remains a paucity of information on functional outcomes after these injuries.

Recent Trends, Technical Concepts and Components of Computer-Assisted Orthopedic Surgery Systems: A Comprehensive Review

Computer-assisted orthopedic surgery (CAOS) systems have become one of the most important and challenging types of system in clinical orthopedics, as they enable precise treatment of musculoskeletal diseases, employing modern clinical navigation systems and surgical tools. This paper brings a comprehensive review of recent trends and possibilities of CAOS systems. There are three types of the surgical planning systems, including: systems based on the volumetric images (computer tomography (CT), magnetic resonance imaging (MRI) or ultrasound images), further systems utilize either 2D or 3D fluoroscopic images, and the last one utilizes the kinetic information about the joints and morphological information about the target bones. This complex review is focused on three fundamental aspects of CAOS systems: their essential components, types of CAOS systems, and mechanical tools used in CAOS systems. In this review, we also outline the possibilities for using ultrasound computer-assisted orthopedic surgery (UCAOS) systems as an alternative to conventionally used CAOS systems.

[Percutaneous screw techniques for the pelvic ring and acetabulum]

In the treatment of pelvic ring and acetabular fractures percutaneous screw osteosynthesis provides the advantage of minimal soft tissue damage. The techniques are frequently used in combination with open osteosynthesis and less frequently as stand-alone procedures. A preoperative planning with the aid of computed tomography (CT) and knowledge of the intraoperative radiological fluoroscopy adjustment are prerequisites for an accurate placement of the screws. This article describes the indications and techniques for frequently used percutaneous screws.

Minimally Invasive Percutaneous Spinopelvic Fixation for Unstable Pelvic Ring Fracture Performed With the Patient in a Lateral Position

Spinopelvic fixation provides a strong fixation for unstable pelvic ring fractures. However, the technique is usually performed with the patient in the prone position, with the applied weight on the anterior superior iliac crests aggravating fracture displacement. We developed a novel approach for minimally invasive percutaneous spinopelvic fixation that is performed with the patient in a lateral (side lying) position. We describe the application of our technique for the treatment of a bilateral pelvic ring and acetabulum fracture in a 79-year-old woman injured in a traffic accident. Initial posterior fixation was performed with the patient in the left-side lying position, using bilateral pedicle screws at L3 and L4 and a left sacral-alar iliac screw and 2 right iliac screws inserted under navigation. The lateral and cranial displacement of the right pelvic ring was reduced percutaneously. One week after this initial surgery, we proceeded with an open anterior reduction and internal fixation of the left pelvic ring and acetabulum fracture. The postoperative course was uneventful and clinical outcomes were satisfactory. Reduction of a pelvic ring fracture in a lateral position, with subsequent spinopelvic fixation, is a reasonable option for the treatment of an unstable pelvic ring fracture.

Mapping of both column acetabular fractures with three-dimensional computed tomography and implications on surgical management

Background

The primary goal of this study was to create a frequency map of a series of surgically treated both-column fractures and to explore its implications on surgical management.

Methods

We used a consecutive series of 71 both-column fractures to create 3-dimensional reconstruction images, which were superimposed and oriented to fit a model hemipelvis template by aligning specific pelvis landmarks. Fracture lines were identified and traced to create a fracture map of both-column fractures. Then the possible clinical implications of fracture line map were explored.

Results

Fracture location is closely related to the distribution of fracture line. Of 71 fractures that met the criteria for inclusion, we found the most common pattern demonstrated by coexisting fracture lines. The anterior column was involved by 66% of the fractures extending obliquely from the anterior superior spine to the ischial spine, while 62% of the fractures involved the anterior column extending approximately vertically from the iliac crest to the acetabular roof. Additionally, 39% of the fractures involved the posterior column traversing posterior wall. Furthermore, the high fracture line intensity (n = 65, 92%) formed a Y-shaped pattern, which highlighted the consistency of the patterns.

Conclusions

Surgically treated both-column fractures display very common patterns. The most common pattern is the low anterior column fracture in nearly two thirds of cases, the high anterior column fracture in three fifths of cases and the posterior column fracture with posterior wall involvement in nearly two fifths of cases. These study results may help surgeons to yield insight relevant to surgical approaches, reduction, fixation strategies and even implant design for both-column fractures.

Comparative Study of Percutaneous Sacroiliac Screw with or without TiRobot Assistance for Treating Pelvic Posterior Ring Fractures

Objectives

To analyze the curative effect of TiRobot surgical robotic navigation and location system‐assisted percutaneous sacroiliac screw fixation and percutaneous sacroiliac screw by traditional fluoroscopy, and to summarize the safety and benefits of TiRobot.

Methods

A total of 91 patients with pelvic posterior ring fractures from December 2015 to February 2018 were included in this study. According to the surgical methods selected by the patients, the patients were divided into a TiRobot surgical robotic navigation and location system group (TiRobot group) and a percutaneous sacroiliac screw fixation group (traditional group). Statistical indicators included the number of sacroiliac screws, the time of planning the sacroiliac screw path, fluoroscopy frequency, fluoroscopy time, operation time, length of incision, blood loss, anesthesia time, the healing process of skin incisions, and fracture healing time. Fracture reduction was evaluated according to the maximum displacement degree at the inlet and outlet view X‐ray or CT. Matta standard was used to evaluate fracture reduction. At the last follow‐up, the Majeed function system was used to evaluate the function.

Results

All patients were followed up for 8 to 32 months. A total of 66 sacroiliac screws were implanted in the TiRobot group. A total of 43 sacroiliac screws were implanted in the traditional group. There were statistically significant differences in terms of fluoroscopy frequency, fluoroscopy time, operation time, incision length, anesthesia time, and blood loss between the two groups; the TiRobot group was superior to the traditional group. The healing time of the TiRobot group and the traditional group was 4.61 ± 0.68 months (range, 3.5–6.3 months) and 4.56 ± 0.78 months (range, 3.4–6.2 months), respectively, and there was no statistical difference. Postoperatively, by Matta standard, the overall excellent and good rate of fracture reduction was 89.28% and 88.57%, respectively. At the last follow‐up, by Majeed function score, the overall excellent and good rate was 91.07% and 91.43%. There was no statistical difference between the two groups.

Conclusion

Sacroiliac screw implantation assisted by TiRobot to treat the posterior pelvic ring fractures has the characteristics of less trauma, shorter operation time, and less blood loss. TiRobot has the characteristics of high safety and accuracy and has great clinical application value.