Radiographic displacement in pelvic ring disruption: reliability of 3 previously described measurement techniques

Posttraumatic Hip Osteoarthritis After Pelvic Ring Injuries

OBJECTIVES

While rates of posttraumatic osteoarthritis after acetabulum fracture have been thoroughly studied, there has been less emphasis on hip osteoarthritis after pelvic ring injuries. The objective of this study was to determine the frequency of posttraumatic hip osteoarthritis in pelvic ring injury patients. It was hypothesized that more severe pelvic ring injuries would be associated with greater rates of posttraumatic hip osteoarthritis.

METHODS

DESIGN

Retrospective Cohort.

SETTING

Urban/Suburban Academic Level I Trauma Center.

PATIENT SELECTION CRITERIA

Subjects were identified using a retrospective search for OTA/AO type A, B, and C pelvic ring injuries. Patients were included if they were aged 18 years or older, had a pelvic ring injury, and had 1 year or more of radiographic follow-up. Patients were excluded if they had prior total hip arthroplasty or hip hemiarthroplasty, femoral neck fracture, acetabulum fracture, femoral head fracture, or inadequate radiographic follow-up.

OUTCOME MEASURES AND COMPARISONS

Both hips were graded using the Tönnis classification at the time of injury and available follow-up pelvis films. Comparison of rate of osteoarthritis progression was made between stable (LC I injuries stable on examination under anesthesia, all APC I injuries) and unstable (APC II, APC III, LC II, LC III, and LC I injuries unstable on examination under anesthesia) pelvic ring injury patients, as well as severity of injury using the Young-Burgess classification.

RESULTS

Two hundred eleven patients were included for final analysis. Average age was 58.8 years (SD 28.1 years, range 18-100 years). Eighty-eight patients (41.7%) were male. One hundred twenty-seven patients underwent nonoperative management, and 84 underwent surgical stabilization. 34.5% (29/84) of patients with unstable pelvic ring injuries and 6.2% (8/127) of patients with stable pelvic ring injuries demonstrated progression of osteoarthritis on the ipsilateral side of their injury ( P < 0.001). More severe pelvic ring injury patterns had a greater rate of posttraumatic osteoarthritis (PTOA) based on the Young-Burgess injury classification (44.4% of LC III vs. 11.1% of LC I pelvic ring injury patients, P < 0.001).

CONCLUSIONS

A significant frequency of posttraumatic osteoarthritis after pelvic ring injuries was identified. A higher rate of progression to PTOA was found with unstable injuries compared with stable pelvic injuries.

LEVEL OF EVIDENCE

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

Closed Reduction and Minimally Invasive Fixation for the Treatment of Bilateral Displaced Posterior Pelvic Ring Disruption

OBJECTIVE

Close reduction and internal fixation have gained popularity for the treatment of pelvic fractures. However, the closed reduction of bilateral displaced posterior pelvic ring disruption is a great challenge even for the most experienced surgeon. In this study, we describe in detail a novel unlocking closed reduction technique (UCRT) frame that allows strong traction for bilateral posterior pelvic ring displacement and presents preliminary clinical outcomes.

METHODS

We retrospectively reviewed 32 patients with bilateral displaced posterior pelvic ring disruptions (AO/OTA 61-C2 and C3) who were initially treated with this technique between July 2017 and July 2022. According to the AO/OTA classification, there were 9 cases (28.12%) of 61-C2, and 23 cases (71.88%) of 61-C3. There were 11 males, 21 females, with an average age of 38.1 years. The interval from injury to operation was 4-27 days, with a cut-off of 12.5 days (receiver operating characteristic curve). Operative time, blood loss, and postoperative radiographic findings were recorded. The functional outcomes and complications were followed.

RESULTS

A total of 30 (93.8%) patients achieved successful closed reduction, whereas 2 required open reduction. The successful closed reduction rate was 95.5% (21/22) in patients whose injury-to-operation time was less than 12.5 days. The vertical displacement percent correction of the obviously displaced hemipelvis was 70.20% ± 16.79% on average. The average degree of pelvic deformity correction was 64.86% ± 17.71%. Thirty patients were followed up for at least 12 months (12-36 months), and no complications of nonunion or redisplacement were observed. The Matta-Tornetta scoring standard revealed that the excellent (25/30) and good (4/30) rate was 96.7%. The Majeed clinical efficacy score revealed that the overall excellent and good rate was 100%. One patient had INFIX-related infection, and 2 reported numbness in the lateral thigh. The numbness was improved after INFIX removal.

CONCLUSIONS

This study presents an updated technique for closed reduction using a UCRT frame for bilateral posterior pelvic ring disruption, which has been shown to be effective, as indicated by excellent surgical and functional outcomes.

Endoscopic-assisted anterior pelvic ring osteosynthesis for pelvic ring injuries: a technical report

INTRODUCTION

In the surgical treatment of pelvic ring injuries (PRIs), there is an increasing adoption of minimally invasive techniques to improve surgical outcomes. Since the introduction of endoscopic-assisted osteosynthesis for PRIs in 2019, various surgical challenges have been identified. To improve surgical and clinical outcomes, we modified the existing procedures and aimed to present the surgical outcomes of patients with pelvic fractures who underwent endoscopic-assisted surgery.

MATERIALS AND METHODS

We conducted a retrospective analysis of patients with PRIs treated with endoscopic technique over a 15-month period. All patients were diagnosed with diastatic symphysis, superior pubic ramus fracture, or both. The postoperative radiological and functional outcomes were assessed and reported. Details of the preoperative planning and surgical procedures were reviewed.

RESULTS

Thirteen patients with PRIs were enrolled: 10 patients for diastatic pubic symphysis (three of whom received superior ramus screw fixation) and three for isolated superior pubic ramus fractures. All surgeries were completed with endoscopic assistance, without the need for conversion to open surgery. The average surgical duration was 204.1 min, the endoscopy time was 103.7 min, and the volume of blood loss was 185.0 ml. Excellent reduction was achieved in all patients according to the Matta/Tornetta criteria and in nine patients according to the Lefaivre criteria. The mean Majeed scores were 71 and 82 and the mean Merle d'Aubigné scores 11 and 15 at 3 and 6 months postoperatively, respectively.

CONCLUSION

Endoscopic-assisted pelvic surgery is a safe and effective treatment alternative for PRIs, particularly when focusing on the anterior pelvic ring. The advantages of this approach, including small incisions and preservation of abdominal and pelvic floor muscle integrity, contribute to improved patient recovery. Future research should focus on comparative studies of this technique with other minimally invasive techniques and open surgery.

Is patient-reported outcome after treatment of unstable pelvic ring injuries related to pelvic symmetry? A prospective study

PURPOSE

To determine the relation between pelvic symmetry, as measured by the cross-measurement technique, and patient-reported outcome measures (PROMs) in terms of functional status and health-related quality of life.

METHODS

In this prospective cohort study, X and Y measurements were taken according to the cross-measurement technique on AP radiographs of patients who were treated for an unstable pelvic ring injury in a level-1 trauma center. Patients completed PROMs at the time of admission (recalled pre-injury score) and one year following their injury, reporting their functional status with the Short Musculoskeletal Function Assessment (SMFA-NL), specifically the lower extremity dysfunction (LED), problems with daily activities (PDA) and mental and emotional problems (MEP) subscales, and quality of life with EuroQol-5D (EQ-5D). Subgroup analyses were also performed. PROMs were used to analyze the relation between pelvic symmetry and patient-reported outcome, using Spearman's Rank correlation coefficients.

RESULTS

A total of 130 patients (mean age 58 (SD18) years) with an unstable pelvic ring injury were included, of which 95 (73%) sustained type-B injuries and 35 (27%) type-C injuries. Sixty-three (49%) patients were treated operatively. The median pelvic symmetry ratio was 1.01 (IQR: 0.05). Weak or no correlations were found between the pelvic symmetry scores and the outcome measurements (Spearman's correlation coefficients: LED r = 0.09; PDA r = 0.11; MEP r=-0.02; and EQ-5D r=-0.08). Subgroup analyses revealed no correlations.

CONCLUSIONS

No significant relation was found between pelvic symmetry, measured radiologically, and functional status and health-related quality of life, one year following an unstable pelvic ring injury.

Functional and Radiological Outcome of Anterior Plate Stabilisation of the Sacroiliac Joint in Unstable Pelvic Injury

Introduction

Sacroiliac joint disruption, resulting from high energy trauma can cause significant morbidity if no proper treatment given. Many techniques can be used to stabilise pelvic ring injuries. We studied the functional and radiological outcome following open reduction and anterior fixation of the sacroiliac joint and agreement between both outcomes.

Material and Methods

This retrospective study involved 15 patients with unstable pelvic injuries requiring surgical intervention from January 2015 to December 2020 who undergone anterior stabilisation of the sacroiliac joint. Radiological outcome assessments were done postoperatively by using Lindahl criteria. The complete functional outcome was assessed at least six months postoperatively when patients were able to weight bear by using Majeed system. Descriptive statistical analysis was performed using IBM SPSS Statistics Version 27.

Results

The participants consist of 73.3% male and 26.7% female patients. A total of 66.7% of patients had a Tile type B pelvic ring injury, and the remaining 33.3% had a Tile type C pelvic ring injury. Based on the Majeed system, 73.3% of patients had excellent functional outcomes, and based on Lindahl criteria; there were 60% of patients who had excellent radiological outcome. However, there was no significant agreement between functional and radiological outcomes.

Conclusion

Definitive fixation of the sacroiliac joint by anterior plate stabilisation provided an excellent functional and radiological outcome mainly due to good anatomical reduction and mechanical stability. However, further study may be needed to evaluate the correlation between functional and radiological outcomes and compare the various method of fixation with a larger sample size.

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.

Fracture displacement of lateral compression type 1 (LC1) Pelvic Ring Injuries: Which measurement methods are reliable and does displacement correlate with adverse events?

PURPOSE

To determine the interobserver reliability of perceived displacement (PD) ≥ 1 cm of lateral compression type 1 (LC1) pelvic ring fractures and to determine if PD correlated with published methods of measuring fracture displacement and adverse events.

METHODS

The injury and follow-up radiographs of 10 patients with nonoperative minimally displaced LC1 injuries were reviewed by 27 orthopaedic trauma surgeons to determine if they perceived an interval fracture displacement ≥ 1 cm. Perceived displacement (PD) was compared to 11 measurements of displacement: the difference in heights of iliac crests (IC), sourcils, and ischial tuberosities on AP/outlet radiographs; the distance from femoral head (FH) to the sacral midline and the distance between the radiographic teardrops (TD) on the AP; the distance from the TD to sacral midline and the difference in distances between the SI joints and the contralateral TD on the inlet. The interobserver reliability and correlation of PD and measured displacement was calculated. The association between PD and adverse events was also evaluated.

RESULTS

PD had weak interobserver reliability (kappa = 0.46). Many of the measurements of displacement were poorly sensitive for PD. The magnification-corrected AP TD measurement had the highest sensitivity (100%) for PD and excellent interobserver reliability (Intraclass correlation 0.97), but had a low specificity (57.1%). All three patients with PD had adverse events while patients without PD had uneventful recoveries (p = 0.008).

CONCLUSIONS

The AP TD measurement detected all cases of PD and had excellent reliability. PD was associated with adverse events, suggesting that accurate and reliable measurements of displacement are warranted.

LEVEL OF EVIDENCE III

Diagnostic.

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.

Standardization and Reproducibility of Dynamic Stress Testing for Occult Pelvic Ring Instability

INTRODUCTION

Examination under anesthesia (EUA) (stress fluoroscopy) is commonly done after pelvic ring injury to identify occult instability because unstable disruptions may displace causing morbidity. The force applied during EUA for these injuries has not been standardized. The purpose of this study was to examine the forces used during the EUA by experienced orthopaedic trauma pelvic surgeons.

METHODS

Orthopaedic traumatologists performed simulated EUA on a cadaver at two North American pelvis and acetabular courses using internal rotation (IR), external rotation, and push-pull maneuvers while wearing a handheld dynamometer to measure force. All surgeons used a comparable method, and each performed EUA multiple times. Maximum forces were measured in Newton (N).

RESULTS

Eighteen surgeons participated. Four had been practicing for <5 years, six for 5 to 10 years, six for 11 to 20 years, and two for >20 years. Surgeons applied a force ranging from 40.4 to 374.9 N during IR, 72.9 to 338.4 N during external rotation, and 25 to 323 N during push-pull, with notable variability seen between surgeons. Three surgeons (18%) had >50-N variability on serial trials of a single EUA maneuver (IR).

DISCUSSION

This is the first study evaluating the forces applied during pelvic EUA used to assess ring stability. Notable variability existed among surgeons performing EUA and in serial examinations by the same surgeon. Additional study is needed to standardize the displacement measured and threshold for instability that guides management.

Advancements in pelvic ring fracture surgery: Assessing INFIX screw placement accuracy with CT navigation

The management of unstable pelvic ring fractures, typically resulting from high-energy trauma, presents a significant clinical challenge due to the complexity of injuries. While effective in many cases, the traditional stabilization methods are fraught with various complications that can significantly impact patient recovery and quality of life (QOL). This study aims to evaluate the efficacy and precision of the anterior subcutaneous internal fixator (INFIX) technique when used with intraoperative computed tomography (CT) navigation, a novel approach intended to mitigate the limitations of conventional treatment modalities. Our retrospective case series encompasses 43 patients who sustained traumatic pelvic injuries and were subsequently treated with the INFIX technique from December 2020 to January 2024. The focus of this analysis was to assess the accuracy of INFIX screw placement facilitated by intraoperative CT navigation. A total of 81 INFIX screws were inserted, and our study findings reveal a high level of precision in screw placement, with only one screw deviating, resulting in an inaccuracy rate of merely 1.2 %. This highlights the significant advantage provided by intraoperative CT navigation. The high level of accuracy not only enhances the stability of the pelvic fixation but also substantially reduces the risk of complications commonly associated with screw misplacement, such as abdominal damage, vascular injury, and issues related to incorrect hardware positioning. In conclusion, the integration of the INFIX technique with intraoperative CT navigation in the treatment of unstable pelvic ring fractures represents a significant advancement in orthopedic trauma surgery. This study provides compelling evidence supporting the efficacy and precision of this approach, suggesting its potential as a superior alternative to traditional fixation methods. Further research, ideally through prospective studies involving larger patient cohorts, is needed to validate these findings and explore the long-term implications of this technique on patient recovery and QOL.

Intelligent robot-assisted fracture reduction system for the treatment of unstable pelvic fractures

BACKGROUND

Precise and minimally invasive closed reduction is the premise of minimally invasive internal fixation. This paper aims to explore the safety and efficacy of a robot-assisted fracture reduction system (RAFR) in the treatment of pelvic fractures and to analyze its clinical advantages and existing problems.

METHODS

The RAFR system intelligently designed the optimal reduction path and target position based on a preoperative three-dimensional(3D) CT scan of the patient. The reduction robotic arm automatically reduced the affected hemipelvis according to the pre-planned reduction path.

RESULTS

The average residual displacement was the 6.65 ± 3.59 mm. According to Matta's criteria, there were 7 excellent, 10 good, and 3 fair, and the excellent and good rate was 85%. No postoperative complications occurred.

CONCLUSION

In our study, the RAFR system could complete accurate and minimally invasive closed reduction for most patients with unstable pelvic fractures, which could achieve good fracture reduction quality and short-term efficacy.

Does Fracture Pattern Really Predict Displacement of LC1 Sacral Fractures?

BACKGROUND

Operative management of minimally displaced lateral compression type-1 (LC1) pelvic ring injuries remains controversial. We aimed to assess the proportion of LC1 pelvic fractures that displaced following nonoperative management as a function of specific ring fracture patterns, and we quantified the magnitude of this displacement.

METHODS

A retrospective review of the billing registry of a level-I trauma center was performed. Two hundred and seventy-three patients with a high-energy LC1 pelvic ring fracture and <5 mm of sacral displacement were included. The fracture pattern was characterized with use of computed tomography (CT) scans and radiographs. Absolute and interval pelvic ring displacement were quantified with use of previously described methodology.

RESULTS

Thirty-five pelvic ring injuries (13%) were displaced. The rate of displacement was 31% (15 of 49) for LC1 injuries involving a complete sacral fracture and bilateral ramus fractures, 12% (7 of 58) for injuries involving a complete sacral fracture and a unilateral ramus fracture, and 10% (5 of 52) for injuries involving an incomplete sacral fracture and bilateral ramus fractures. In displaced injuries, the average interval displacement was 4.2 mm (95% confidence interval [CI], 1.8 to 6.8) and the final displacement was 9.9 mm ± 4.2 mm.

CONCLUSIONS

Our study suggests that fracture characteristics can be used to predict the likelihood of displacement of LC1 fractures that are treated without surgery. To our knowledge, the present study is the first to describe the magnitude of displacement that may occur in association with LC1 pelvic ring injuries that are treated nonoperatively; however, further studies are needed to determine the clinical impact of this displacement.

LEVEL OF EVIDENCE

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

Post Post-Mobilization Films for LC1 Pelvic Ring Injuries: Follow up Stress Imaging Demonstrates Minimal Utility

OBJECTIVE

To assess the utility of outpatient postmobilization radiographs in the nonoperative treatment of lateral compression type I (LC1) (OTA/AO 61-B1) pelvic ring injuries.

DESIGN

Retrospective series.

SETTING

Academic, Level 1 trauma center, 2008-2018.

PATIENTS/PARTICIPANTS

A series of 173 patients with nonoperatively treated LC1 pelvic ring injuries was identified. Of these, 139 received a complete set of outpatient pelvic radiographs with which to assess displacement.

INTERVENTION

Outpatient pelvic radiographs to assess additional fracture displacement and potential need for surgical intervention.

MAIN OUTCOME MEASUREMENTS

Rate of conversion to late operative intervention based on radiographic displacement.

RESULTS

No patient in this cohort received late operative intervention. A majority of the patients sustained incomplete sacral fractures (82.6%) and unilateral rami fractures (75.1%), and 92.8% demonstrated less than 10 mm of displacement on their final radiographs.

CONCLUSIONS

There is a low utility of repeat outpatient radiographs of stable, nonoperative LC1 pelvic ring injuries as they do not undergo late displacement.

LEVEL OF EVIDENCE

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

Intelligent robot-assisted minimally invasive reduction system for reduction of unstable pelvic fractures

OBJECTIVE

Currently, minimally invasive internal fixation is recommended for the surgical treatment of unstable pelvic fractures. The premise and difficulty of minimally invasive internal fixation are minimally invasive reduction of fractures. This review aimed to investigate the indications, surgical strategy and techniques, safety, and efficacy of intelligent robot-assisted fracture reduction (RAFR) system of pelvic ring injuries.

METHODS

This retrospective study reviewed a case series from March 2021 to November 2021. A total of 22 patients with unstable pelvic fracture injuries underwent minimally invasive internal fixations. All pelvic ring fractures were reduced with our intelligent RAFR system. The robot system intelligently designs the optimal position and reduction path based on the patient's preoperative 3D CT. During the operation, the three-dimensional visualization of the fracture is realized through image registration, and the Robot completes the automatic reduction of the fracture. The global 3D point cloud error between the preoperative planning results and the actual postoperative reduction results was calculated. The postoperative reduction results of residual displacement were graded by the Matta Criteria.

RESULTS

Minimally invasive closed reduction procedures were completed in all 22 cases with our RAFR system. The average global 3D point cloud reduction error between the preoperative planning results and the actual postoperative reduction results was 3.41mm±1.83mm. The mean residual displacement was 4.61mm±3.29mm. Given the Matta criteria, 16 cases were excellent, five were good, and one was fair, with an excellent and good rate of 95.5%.

CONCLUSION

Our new pelvic fracture reduction robot system can complete intelligent and minimally invasive fracture reduction for most patients with unstable pelvic fractures. The system has intelligent reduction position and path planning and realizes stable pelvis control through a unique holding arm and a robotic arm. The operation process will not cause additional damage to the patient, which fully meets the clinical requirements. Our study demonstrated the safety and effectiveness of our robotic reduction system and its applicability and usability in clinical practice, thus paving the way towards Robot minimally invasive pelvic fracture surgeries.

What Are the Key Factors of Functional Outcomes in Patients with Spinopelvic Dissociation Treated with Triangular Osteosynthesis?

For patients with spinopelvic dissociation (SPD), triangular osteosynthesis is the current method for the fixation of the posterior pelvis. This study aimed to assess the recovery process and radiographic parameters associated with the functional outcomes in patients with SPD treated by triangular osteosynthesis. We collected data from 23 patients with SPD. To investigate the key aspect regarding the functional outcomes of these patients, we measured pre- and post-operative parameters, and a statistical analysis adjusted for age, gender, and time windows was used. The radiographic displacement measurement in the pre-operative period showed that the EQ-5D-5L increased by 2.141 per outlet ratio unit. The EQ-5D-5L increased by 1.359 per inlet ratio unit and 1.804 per outlet ratio during the postoperative period. The EQ-VAS increased significantly only with the inlet ratio in the postoperative period (1.270 per inlet ratio). A vertical reduction in SPD during the surgery can achieve more satisfactory outcomes than a horizontal anatomical reduction, in which the horizontal displacement causes inferior functional outcomes.

Surgical management of paediatric pelvic fractures: a prospective case series and early experience from a level one Egyptian trauma centre

PURPOSE

We aimed to report our early experience treating paediatric pelvic fractures (PPF) surgically, reporting on indications, outcomes, and complications.

METHODS

Patients aged 0-15 with PPF treated surgically at a level I trauma centre were included prospectively between 2016 and 2018. Fractures were classified according to AO/OTA classification system. Functional evaluation was performed using a modification of the Majeed functional scoring system. Radiological evaluation of vertical and posterior displacement was performed according to Matta and Tornetta criteria and the method described by Keshishyan et al. for assessing pelvic rotational asymmetry.

RESULTS

We included 45 patients (77.8% males and 22.2% females), with a mean age of 9.53 ± 3.63 and 19.87 ± 8.84 months of mean follow-up. The functional outcome was excellent in 42 (93.3%) patients, good in two (4.4%), and fair in one (2.2%). Radiologically, the vertical displacement improved from 5.91 ± 4.64 to 3.72 ± 2.87 mm (p-value 0.065), the posterior displacement improved from 7.87 ± 8.18 to 5.33 ± 13.4 mm (p-value 0.031), and the symphyseal diastasis improved from 9.88 ± 7.51 mm to 7.68 ± 3.18 mm (p-value 0.071). Residual pelvic asymmetry improved from 1.2 ± 0.61 to 0.8 ± 0.7 (p-value 0.001). Complications occurred in 21 (46.7%) patients, 11 (24.4%) pin tract infection, six (13.3%) limb length discrepancy, two (4.4%) prominent metals, one (2.2%) subcutaneous haematoma, one (2.2%) infected ISS.

CONCLUSIONS

We achieved acceptable functional and radiological outcomes after surgically treating a group of patients with PPF, which was relatively safe with minimal complications. The proper approach and fracture fixation tool should be tailored according to the fracture classification and the presence of associated injuries.

The effect of pelvic ring rotation and tilt on the radiographic teardrop distance: an important consideration in the assessment of dynamic displacement on stress radiographs

PURPOSE

The purpose of this study was to determine the effect of rotation and tilt on the radiographic teardrop distance (TD) on anteroposterior (AP) pelvis radiographs.

METHODS

Radiographic examination of a pelvis models was conducted utilizing increasing degrees of beam rotation and tilt on portable C-arm fluoroscopy. The TD, x-plane rotation (symphyseal-mid-sacrum distance (SMS)), and y-plane tilt (sacroiliac joint-symphysis distance (SIS)) were measured by four independent observers. Interobserver reliability was assessed using intraclass correlations.

RESULTS

TD was altered by less than 2 mm with up to 7.5° fluoroscopic rotation (SMS: 3 cm) and up to 30° of inlet and 15° of outlet (SIS: ± 3.3 cm). SMS distance effectively corresponded to the degree of rotation present (r = 1.00, CI: 0.97 to 1.00, p < 0.0001) and was strongly correlated to TD (r = -0.95, CI: -0.99 to -0.67, p = 0.001). SIS distance effectively corresponded to the degree of tilt present (r = -0.97, CI: -0.99 to -0.88, p < 0.0001) and was correlated to TD (r = 0.94, CI: 0.75 to 0.99, p = 0.0001). Linear regression models determined that, with every degree of rotation and tilt, TD was altered by 0.4 mm and 0.09 mm, respectively (p = 0.0004, r² = 0.93 and p < 0.0001, r² = 0.94, respectively). Interobserver reliability among observers was excellent (0.92).

CONCLUSION

The TD has excellent interobserver reliability and is minimally impacted by up to 7.5° of rotation, 30° inlet tilt, and 15° of outlet tilt. Utilization of these thresholds may ensure reliability of TD measurements when assessing pelvis stress radiographs.

Simultaneous reduction and fixation of concomitant acetabular fracture and ipsilateral sacroiliac joint injury through the pararectus approach: a technical report and early radiological outcome

PURPOSE

Osteosynthesis for acetabular fractures with ipsilateral sacroiliac joint (SIJ) injuries remains challenging for orthopedic surgeons, despite the evolution of surgical approaches, such as the pararectus approach, and treatment sequences. The study aimed to describe the details of the treatment of acetabular fracture with ipsilateral SIJ injury by the pararectus approach and to report its surgical outcomes.

METHODS

We retrospectively assessed patients with acetabular fractures and ipsilateral SIJ injuries undergoing osteosynthesis by the pararectus approach over a three-year period. Evaluation parameters of the quality of reduction of both acetabulum and pelvis injuries were, among others, Matta's criteria, Lefaivre's criteria, inlet/outlet ratios, and maximal gap measured on computed tomography (CT) scans.

RESULTS

Ten patients (seven men and three women) were enrolled. Pelvic ring injuries classified as AO B2.3 and acetabular fractures involving two columns were the most common fractures, accounting for 70% and 60%, respectively. Radiological evaluation for pelvic ring injury revealed three excellent and seven good results according to Matta's criteria, as well as five excellent, three good, and one fair results according to Lefaivre's criteria. Inlet and outlet ratios were between 0.84-1.06 and 0.93-1.60, respectively. The distance of the sacroiliac joints significantly improved postoperatively in both axial and coronal views (P = 0.002). Further, the maximal articular gap and step-off of acetabular fractures on axial, coronal, and sagittal view CT scans showed statistically significant improvements after osteosynthesis.

CONCLUSION

Simultaneous reduction and fixation of acetabular fractures with ipsilateral SIJ injuries using the pararectus approach achieved satisfactory radiological outcomes.

LEVEL OF EVIDENCE

IV.

TRIAL REGISTRATION

Retrospectively registered.

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

SUMMARY

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

Morphological Asymmetry of Pelvic Rings: A Study Based on Three-Dimensional Deviation Analysis

OBJECTIVE

To evaluate the morphological asymmetry of pelvic rings existing in healthy individuals in terms of three-dimensional (3D) geometric shapes.

METHODS

This study was a retrospective self-control study. CT images of healthy pelvises, scanned from Jan 2014 to Jan 2019, were taken from 159 subjects (88 males and 71 females) aged 20 to 59 years (39.1 ± 8.7 years). Digital pelvic ring models were reconstructed from CT images and then flipped over the corresponding sagittal planes to obtain their mirrored models. A 3D deviation analysis of a pelvic ring was conducted between the original model and its mirrored model via model registration and quantification of the geometric differences. Next, the pelvic rings were split to the left and right hipbones. The same flipping procedures as done by pelvic rings were performed for left hipbones to obtain their mirrored models. A 3D deviation analysis was also performed between the left and right hip bones. Quantitative variables representing deviation mainly included the average deviation (AD) and the maximum deviation (MD). MDs over 4 mm and 10 mm were deemed as critical levels for evaluating the severity of asymmetry as per Matta's scoring system. The quantitative assessments of the asymmetry covered pelvic rings, bilateral hip bones and the specific anatomic regions of a hip bone.

RESULTS

157 out of 159 pelvic rings (98.74%) had more than 4 mm of the MD and 27 (16.98%) of them exceeded 10 mm of the MD. The MD of pelvic rings was 1.23 times as high as that for the bilateral hip bones (7.46 mm vs. 6.08 mm, P < 0.05). The ADs of pelvic rings and bilateral hip bones were 1.28 mm and 0.94 mm, respectively (P < 0.05); 2.27% of the surface points of a pelvic ring had more than 4 mm geometric deviations compared with its mirrored model, while 0.59% (P < 0.05) of bilateral hip bones were on the same level of deviation. 119 out of 159 pelvic iliac crests (74.8%) had MDs more than 4 mm, and 15 (9.4%) reached 10 mm or more. Only 15 (9.4%) pelvises presented asymmetric features in the area of obturator foramen where the MDs exceeded 4 mm.

CONCLUSIONS

Pelvic asymmetry exists in the general population, but 3D geometric symmetry is present in specific anatomic regions. It implies that restoring the 3D symmetry of specific anatomic regions is more reliable than "restoring the symmetry of pelvic ring" in pelvic ring reduction or pelvic fixation design.

Three-year functional outcome after open pelvic fracture treatment: a retrospective case series from a level I trauma center

PURPOSE

Open pelvic fractures have high mortality rates, and survivors may have ongoing functional deficits from severe trauma and invasive life-saving procedures. However, there are limited reports regarding the functional status evaluation following open pelvic fractures. We aimed to report the treatment experiences and short-term functional outcomes of patients with open pelvic fractures.

METHODS

We retrospectively reviewed the data of 19 consecutive patients with pelvic fractures who underwent treatment at a single institute between January 2014 and June 2018. The resuscitation protocol, osteosynthesis strategy, reduction quality of the pelvic ring, and functional outcomes were analyzed.

RESULTS

The incidence and mortality rates in patients with open pelvic fractures were 4.9 and 21.6%, respectively. Ten, one, and seven of the open wounds related to the pelvic fractures were located in Faringer zones I, II, and III, respectively. Fractures of four patients were categorized as classes 1 and 2, and those of 11 patients as class 3, according to the Jones-Powell classification. Eleven of 19 (57.9%) and 9 of 19 (47.5%) revealed excellent reduction quality by Matta/Torenetta and Lefaivre criteria, respectively. The Merle d'Aubigné score improved at each evaluation but stagnated after 24 months. The Majeed hip score also improved at the 12-month evaluation but the improvement stopped thereafter. At a 3-year follow-up, the patients with excellent reduction of the pelvic ring showed the highest functional performances.

CONCLUSION

Improvements in functional status of patients with open pelvic fractures can be anticipated based on the reduction quality of the pelvis ring.

Emergency Department Stress Radiographs of Lateral Compression Type-1 Pelvic Ring Injuries Are Safe, Effective, and Reliable

BACKGROUND

Occult instability of lateral compression type-1 (LC1) pelvic ring injuries may be determined with a fluoroscopic stress examination under anesthesia (EUA) performed in the operating room. We hypothesized that LC1 injuries, similar to some fractures of the extremities, could be radiographically stressed for stability in the emergency department (ED). Our primary objective was to determine if stress examination of LC1 fractures could be safely and accurately performed in the ED and could be tolerated by patients.

METHODS

A prospective, consecutive series of 70 patients with minimally displaced LC1 pelvic injuries (<10-mm displacement on presentation) underwent stress examinations performed by the on-call orthopaedic resident in the ED radiology suite. The stress examination series included static 40° inlet, internal rotation stress inlet, and external rotation stress inlet views. Pelvic fractures that had positive stress results (≥10 mm of overlap of the rami) were indicated for a surgical procedure. These fractures also underwent EUA in order for the 2 techniques to be compared.

RESULTS

All patients tolerated the ED stress examination without general anesthetic or hemodynamic instability. Fifty-seven patients (81%) had negative stress results and were allowed to bear weight. All patients with negative stress results who had 3-month follow-up went on to radiographic union without substantial displacement. For the patients with a positive stress result in the ED, the mean displacement was 15.15 mm (95% confidence interval [CI], 10.8 to 19.4 mm) for the ED stress test and 15.60 mm (95% CI, 11.7 to 19.4 mm) for the EUA (p = 0.86). Two patients with a negative ED stress test did not mobilize during their hospitalization and underwent EUA and conversion to a surgical procedure. Thus, a total of 11 patients underwent both stress testing in the ED and EUA; no patient had a positive result on one test but a negative result on the other.

CONCLUSIONS

ED stress examination of LC1 injuries is a safe and reliable method to determine pelvic ring stability. The displacement measured in the ED stress examination is similar to the displacement measured under general anesthesia. Furthermore, a negative ED stress examination predicts successful nonoperative treatment. Given the results of this study, we encourage the use of stress examination in the ED for LC1-type injuries involving complete sacral fractures only. Widescale adoption of this streamlined protocol may substantially diminish cost, anesthetic risk, and potential operations for patients.

LEVEL OF EVIDENCE

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

Postoperative Reduction Quality May Be the Most Important Factor That Causes Worse Functional Outcomes in Open and Closed Pelvic Fractures

Background

Data on the functional outcomes of patients with open pelvic fractures after osteosynthesis are limited, and whether open fracture is a risk factor for worse outcomes, as compared with closed fracture, remains unclear. This study aimed to compare the functional outcomes of patients with open and closed pelvic fractures and evaluate potential factors that might affect outcomes.

Methods

Overall, 19 consecutive patients with open pelvic fractures and 78 patients with closed pelvic fractures between January 2014 and June 2018 were retrospectively reviewed. All fractures were surgically treated, with a minimal follow-up period of three years. Patients’ demographic profile, associated injuries, management protocol, quality of reduction, and outcomes were recorded and analyzed.

Results

Patients with open pelvic fractures had higher new injury severity score, higher incidence of diverting colostomy, and longer length of stay. Both radiological and functional evaluations revealed no significant differences between the two groups at 1-year and 3-year evaluations. Multiple logistic regression analysis identified poor radiological outcomes (using Lefaivre criteria) and longer length of stay as risk factors for worse short-term functional outcomes. At 3-year evaluation, fair-to-poor radiological outcomes (using Matta/Tornetta and Lefaivre criteria) and the presence of diverting colostomy were potential risk factors.

Conclusions

Compared with closed pelvic fracture, open pelvic fracture was not an indicator of worse functional outcomes. Functional outcomes may be comparable between patients with open and closed pelvic fractures at different time points within three years postoperatively. Achieving anatomical reduction in a fracture is crucial, because it might affect patient satisfaction.

Nonoperative Treatment of Select Lateral Compression Type II Pelvic Ring Injuries (OTA/AO 61B2.2) Results in a Low Rate of Radiographic Displacement

OBJECTIVES

To quantify radiographic outcomes and to identify predictors of late displacement in the nonoperative treatment of lateral compression type II (LC-2) pelvic ring injuries.

DESIGN

Retrospective review.

SETTING

Two Level 1 trauma centers.

PATIENTS/PARTICIPANTS

Thirty eight patients 18 years of age or older with LC-2 pelvic ring injuries were included in the study.

INTERVENTION

Nonoperative treatment.

MAIN OUTCOME MEASUREMENTS

Crescent fracture displacement (CFD) was measured on initial axial computed tomography scan. Change in pelvic ring alignment was measured by the deformity index, simple ratio, and inlet and outlet ratios on successive plain radiographs.

RESULTS

Patients in this study had minimally displaced LC-2 pelvic ring injuries, with median initial CFD of 2 mm and median initial deformity index of 2%. No patients had a change of more than or equal to 10 percentage points in deformity index over the treatment period, but small amounts of displacement were seen on the other ratios. No patients initially selected for nonoperative treatment converted to operative treatment. No radiographic predictors of late displacement were identified. Bilateral pubic rami fractures and the presence of a complete sacral fracture ipsilateral to the crescent fracture were not associated with late displacement.

CONCLUSIONS

A spectrum of injury severity and stability exists in the LC-2 pattern. Nonoperative treatment of LC-2 injuries with low initial deformity and CFD results in minimal subsequent displacement.

LEVEL OF EVIDENCE

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

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

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

Infection after the use of INFIX in Pelvic Ring Injuries

INTRODUCTION

The purpose of this study is to report on infection with anterior subcutaneous internal pelvic fixation (INFIX) for pelvic ring injuries and the outcomes of treatment.

METHODS

An IRB-approved retrospective study was performed using trauma databases of a level one and level two trauma center from 2012-2018. Infection after the INFIX procedure was diagnosed in 10 of 179 cases. Treatment included formal irrigation and debridement, removal of the hardware, and culture-specific antibiotics. Patients were followed for a minimum of 12 months. Recorded outcomes include X-rays, Majeed scores, and the presence of any loss of reduction using reduction parameters.

RESULTS

Time to detect the infection was 54.2 ± 24.3 days (range 24-90, median 56 days). Staphylococcus aureus was the most common bacteria isolated. The average follow-up was 830 ± 170 days (range 575-1088 days). All patients went on to the radiographic union. There were no recurrent infections or osteomyelitis at the latest follow-up. Patients maintained their reduction after INFIX removal (KI), and Majeed scores ranged from 72 to 96 (seven good, three excellent).

DISCUSSION

Infections after using the INFIX procedure were dealt with by irrigating and debriding the wounds, removing the INFIX with culture-specific antibiotics for 2-6 weeks. Implants were maintained for at least 25 days, and there was no loss of reduction. There were no long-term sequelae noted in this small series or the literature review included in this paper.

Validation of Relative Motion Measurement Method of Lateral Compression Pelvic Fractures During Examination Under Anesthesia

OBJECTIVES

To determine if the relative distance between the acetabular teardrops on unstressed and lateral compressive stress examination under anesthesia (EUA) pelvic fluoroscopic images is reproducible between independent reviewers.

DESIGN

Retrospective database review.

SETTING

Level 1 trauma center.

PATIENTS/INTERVENTION

Fifty-eight patients with a lateral compression type 1 pelvic ring injury who underwent EUA.

MAIN OUTCOME MEASURE

Validation of EUA objective measurements between blinded, independent reviewers using interclass and intraclass correlation coefficients.

RESULTS

There was excellent interobserver and intraobserver reliability between all reviewers. Values for each intraclass correlation coefficients (including 95% confidence intervals) were between 0.96 (0.95-0.098) and 0.99 (0.99-0.99) for all measurements. P values were <0.0001 for all measured parameters.

CONCLUSIONS

The relative change in distance between the acetabular tear drops during lateral compressive EUA of lateral compression type 1 pelvic injuries is reliable between independent reviewers. This allows for accurate, objective measurement of pelvic motion independent of patient size or body habitus.

LEVEL OF EVIDENCE

Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Exploring partial intrinsic and extrinsic symmetry in 3D medical imaging

We present a novel methodology to detect imperfect bilateral symmetry in CT of human anatomy. In this paper, the structurally symmetric nature of the pelvic bone is explored and is used to provide interventional image augmentation for treatment of unilateral fractures in patients with traumatic injuries. The mathematical basis of our solution is based on the incorporation of attributes and characteristics that satisfy the properties of intrinsic and extrinsic symmetry and are robust to outliers. In the first step, feature points that satisfy intrinsic symmetry are automatically detected in the Möbius space defined on the CT data. These features are then pruned via a two-stage RANSAC to attain correspondences that satisfy also the extrinsic symmetry. Then, a disparity function based on Tukey's biweight robust estimator is introduced and minimized to identify a symmetry plane parametrization that yields maximum contralateral similarity. Finally, a novel regularization term is introduced to enhance similarity between bone density histograms across the partial symmetry plane, relying on the important biological observation that, even if injured, the dislocated bone segments remain within the body. Our extensive evaluations on various cases of common fracture types demonstrate the validity of the novel concepts and the accuracy of the proposed method.

Lateral compression type 1 (LC1) pelvic ring injuries: a spectrum of fracture types and treatment algorithms

Lateral compression type 1 (LC1) fractures are the commonest pelvic ring injury. However, they represent a heterogenous spectrum of injury mechanisms and fracture patterns, resulting in a lack of strong evidence for a universally agreed treatment algorithm. Although consensus exists that LC1 fractures have a preserved posterior ligamentous complex and are vertically stable, controversy persists around defining internal rotational instability. As such, treatment strategies extend from routine non-operative management through to dynamic imaging such as examination under anaesthetic (EUA) or stress radiographs to guide fixation algorithm. Multiple protocols sit between these two, all with slightly different thresholds for advocating surgery or otherwise, exemplifying a broad lack of consensus that is not seen for other, more severe, grades of pelvic ring injury. In the following review we discuss the evolving concepts of pelvic ring instability and management, starting from a historical perspective, through to current trends and controversies in LC1 fracture treatment. Emerging directions for research and emerging pharmacological and surgical treatments/technologies are also considered and expert commentary from 3 leading centres provided. The distinction is made between LC1 fracture arising from high-energy trauma and those following low-energy falls from standing height (so-called fragility fractures of the pelvis-FFP), since these two patient groups have different functional requirements and medical vulnerabilities. Issues pertaining to FFP are considered separately.

Measuring Lateral Screw Protuberance Is a Clinically Accurate Method for Quantifying Femoral Neck Shortening

OBJECTIVES

The purpose of this study is to compare the reliability and accuracy of the screw protuberance method (SPM) and overlay method (OM) for measuring femoral neck shortening on anterior-posterior (AP) radiographs. The secondary aim is to investigate the changes in reliability and accuracy with varying femoral rotation.

METHODS

Radio-opaque femur sawbone models were fitted with either 3 cancellous screws or a sliding hip screw implant. Anterior-posterior radiographs were obtained using C-arm fluoroscopy with femoral neck shortening up to 15 mm and with the femoral shaft in 30 degrees of internal rotation to 30 degrees of external rotation (ER). Four observers measured femoral neck shortening at 2 time points. Intraobserver and interobserver reliability were calculated using the intraclass coefficient. Accuracy was analyzed through a Bland-Altman agreement statistic stratified by femoral rotation.

RESULTS

Both measurement techniques displayed excellent reliability, regardless of femoral rotation or implant. There was a significant difference in femoral neck shortening measurements with rotation for both the OM (P < 0.001) and SPM (P < 0.001). Both methods are accurate within 1 mm of the actual magnitude of shortening from 30-degree internal rotation to 15-degree ER. At 30-degree ER, shortening was underestimated by -2.10 mm using the OM (95% confidence interval, -2.43 to -1.76; P < 0.01) and by -1.64 mm using the SPM (95% confidence interval, -1.83 to -1.45; P < 0.01).

CONCLUSION

This study demonstrates that both the OM and SPM are accurate and reliable assessments for femoral neck shortening; however, both methods are sensitive to extreme ER. Given the simplicity of the SPM technique, it may have increased utility for pragmatic research studies.

Radiostereometric Analysis Allows Assessment of the Stability and Inducible Displacement of Pelvic Ring Disruptions during Healing: A Case Series

There is currently no accurate data on fracture displacement during the rehabilitation of pelvic ring injuries. This study investigated the use of radiostereometric analysis (RSA) in assessing the stability of C1 pelvic ring injuries stabilised with a posterior plate and an anterior external fixator. Six patients, instructed to weight-bear as tolerated after surgery, were reviewed at 2, 4, 6, 12, 26, 52 and 104 weeks. The external fixators were removed at 6 weeks. Outcomes, including the Iowa Pelvic Score (IPS), and complications were recorded. Fracture stability was assessed using measurements on plain radiographs and RSA. All patients progressed to full weight-bearing without support within 6 weeks. At 104 weeks, the IPS was excellent in four patients, good in one patient and fair in one patient. Plain radiographs showed that all fractures were well reduced, and no loss of reduction occurred over time. By contrast, RSA measurements identified displacement in all cases. The maximum three-dimensional (3D) displacement at any time point in each patient ranged from 2 to 10 mm. Two patients with the largest displacement over time had the lowest IPS. RSA also demonstrated displacements above the currently defined normal threshold through the ‘un-injured’ sacroiliac joint in the same two patients, suggesting a subtle C2 injury, missed at initial assessment. This study demonstrates the limitations of plain radiographs in assessing pelvic fracture stability and displacement during healing, and the potential of RSA to monitor more accurately the effects of stabilisation and weight-bearing on fracture stability.

Validated Radiographic Scoring System for Lateral Compression Type 1 Pelvis Fractures

OBJECTIVES

To develop a radiographic fracture scoring system for lateral compression type 1 (LC-1) pelvic fractures based on OTA/AO survey data and to preliminarily evaluate this system within an LC-1 pelvis fracture cohort.

DESIGN

Survey study with validation patient cohort.

SETTING

Two Level 1 academic trauma centers.

PATIENTS/PARTICIPANTS

Attendings (n=111) at the 2013 OTA/AO national meeting reviewed imaging from 27 LC-1 fractures and indicated surgical recommendations ("yes/no"). A separate LC-1 fracture cohort (33 patients) was used to evaluate the scoring system.

INTERVENTION

The LC-1 scoring system (range: 5-14) based on radiographic morphology of sacral, superior ramus (SR), and inferior ramus (IR) fracture components.

MAIN OUTCOME MEASUREMENT

Numeric scores were compared against (1) OTA/AO attendees' operative recommendations and (2) LC-1 cohort treatment and outcomes.

RESULTS

Operative tendency of OTA/AO survey respondents-defined as the percent of "yes" responses to recommend surgical stabilization-was highly correlated with radiographic findings: sacral displacement {odds ratio (OR) = 18.9 [95% confidence interval (CI): 11.7-30.6]}; sacral column 2-3 versus 1 [OR = 5.7 (95% CI: 3.9-8.3)]; Denis classification [OR = 10 (95% CI: 6.7-14.9); IR displacement OR = 3.4 (95% CI: 2.3-4.8)]; and SR fracture [OR = 1.9 (95% CI: 1.3-2.8)]. Total scores <7 were 81% accurate in predicting nonoperative treatment. Total scores >9 were 89% accurate in predicting an operative recommendation. In the LC-1 cohort, scoring accuracy was 100% (95% CI: 85%-100%).

CONCLUSIONS

Based on survey results and patient cohort data, scores <7 predict nonoperative treatment recommendation, scores >9 indicate surgical recommendations, and scores 7-9 indicate indeterminate stability that should be further evaluated.

Radiological measurement of pelvic fractures using a pelvic deformity measurement software program

BACKGROUND

It is difficult for the surgeon to measure pelvic displacement in the closed reduction operation for unstable pelvic fracture. We therefore developed a pelvic deformity measurement software program based on standardized radiographs. The objectives of the present study were to evaluate the inter-observer reliability of the program for measuring specific fracture types on preoperative pelvic films and to assess the validity of the measurement software program by comparing it with a gold standard.

METHODS

Twenty-five patients diagnosed with AO/OTA type B or C pelvic fractures with the unilateral pelvis fractured and dislocated were included in this study. Four separate observers repeatedly determined the translational and rotational patterns and outcomes using the software program and hand measurement, and calculated the displacement using computed tomography (CT) coupled with a three-dimensional (3D) CT model. The validity of the measurement software was calculated by assessing the consistency between the software measurements and the gold standard. Additionally, inter-observer reliability was assessed for the software. The software was also applied in preliminary clinical practice for closed reduction procedures.

RESULTS

The overall inter-observer reliabilities of the software program, CT coupled with 3D reconstruction, and hand measurements were high, with kappa values of 0.956, 0.958, and 0.853, respectively. The software showed validity similar to that of CT coupled with 3D reconstruction (0.939 vs. 0.969), and better than that of hand measurement (0.939 vs. 0.858). A preliminary clinical application demonstrated that the software is effective for guiding closed reduction of pelvic fractures.

CONCLUSIONS

Our newly established pelvic deformity measurement program is a reliable and accurate tool for analyzing pelvic displacement patterns and can be used for guidance of closed reduction and planning of the reduction pathway.

LEVEL OF EVIDENCE

III.

Technical Considerations and Fluoroscopy in Percutaneous Fixation of the Pelvis and Acetabulum

Surgical treatment of the pelvic ring and acetabulum continues to evolve. Improved imaging technology and means for closed reduction have meant that percutaneous techniques have gained popularity in the treatment of the pelvic ring and, more recently, in the acetabulum. Potential benefits include decreased soft-tissue dissection, blood loss, and surgical time. However, these are technically demanding procedures that require substantial expertise from both the surgeon and the radiographer. This article details the necessary fluoroscopic views and general methods used in percutaneous techniques around the pelvis and acetabulum. Despite most studies reporting good-to-excellent clinical and radiographic results, further work is needed to facilitate standardization and optimization of these outcomes.

Feasibility of iliosacral screw placement in patients with upper sacral dysplasia

Background

Exact knowledge of the sacral anatomy is crucial for the percutaneous insertion of iliosacral screws. However, dysplastic anatomical patterns are common. In addition to a preoperative computed tomography (CT) analysis, conventional radiographic measures may help to identify upper sacral dysplasia and to avoid damage to surrounding structures. Aiming to further increase safety in percutaneous iliosacral screw placement in the presence of sacral dysmorphism, this study examined the prevalence of previously established radiographic signs and, in addition, defined the “critical SI angle” as a new radiographic criterion.

Methods

Pelvic CT scans of 98 consecutive trauma patients were analysed. Next to assessment of established signs indicating upper sacral dysplasia, the critical sacroiliac (SI) angle was defined in standardized pelvic outlet views.

Results

The critical SI angle significantly correlates with the presence of mammillary bodies and an intraarticular vacuum phenomenon. With a cut-off value of − 14.2°, the critical SI angle detects the feasibility of a safe iliosacral screw insertion in pelvic outlet views with a sensitivity of 85.9% and a specificity of 85.7%.

Conclusions

The critical SI angle can support the decision-making when planning iliosacral screw fixation. The clinical value of the established signs of upper sacral dysplasia remains uncertain.

The Longitudinal Short-, Medium-, and Long-Term Functional Recovery After Unstable Pelvic Ring Injuries

OBJECTIVES

Describe the trajectory of functional recovery for patients with surgically treated unstable pelvic ring injuries from baseline to 5 years.

DESIGN

Prospective cohort study.

SETTING

Level I Trauma Center.

PATIENTS/PARTICIPANTS

One hundred eight adult patients with surgically treated pelvic fractures (72% OTA/AO 61 B1-B3 and 28% OTA/AO 61 C1-C3) were enrolled into the institutions orthopaedic trauma database between 2004 and 2015. The cohort was 78% men with a mean age of 44.9 years and injury severity score of 16.9.

INTERVENTION

Surgical pelvic stabilization.

MAIN OUTCOME MEASUREMENTS

Function was measured at baseline and prospectively at 6 months, 1, and 5 years postoperatively using the Short Form-36 Physical Component Score (SF-36 PCS). The trajectory was mapped, and the proportion of patients achieving a minimal clinically important difference (MCID) between time points was determined.

RESULTS

The mean SF-36 PCS improved for the entire group between 6 and 12 months (P = 0.001) and between 1 and 5 years (P = 0.02), but did not return to baseline at 5 years (P < 0.0001). The proportion of patients achieving a MCID between 6 and 12 months and 1 and 5 years was 75% and 60%, respectively. The functional level was similar between type B and C groups at baseline (P = 0.5) and 6 months (P = 0.2); however, the type B cohort reported higher scores at 1 year (P = 0.01) and 5 years (P = 0.01). Neither group regained their baseline function (P < 0.0001).

CONCLUSIONS

Functional recovery for patients with surgically treated pelvic fractures is characterized by an initial decline in function, followed by sharp improvement between 6 and 12 months, and continued steady improvement between 1 and 5 years. Type B injuries show better early recovery than type C and reach a higher level of function at the final follow-up. Despite the proportion of patients achieving MCID, patients do not regain the preinjury level of function.

LEVEL OF EVIDENCE

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

Quality of reduction correlates with clinical outcome in pelvic ring fractures

INTRODUCTION

Posttraumatic pelvic deformity is associated with pain and loss of function. This study aimed to test the correlation of functional outcome in patients with pelvic fractures with the postoperative radiographic quality of reduction.

METHODS

Consecutive patients with an isolated traumatic pelvic fracture that required closed or open reduction between 07/2015 and 07/2017 and had a completed follow-up of at least 6 months were included (N = 31, mean age 50 years, SD 21 years, range, 16 to 88 years). Majeed and Timed Up & Go were obtained from a prospective outcome database at 6 months and last follow-up (mean 10 months, SD 5 months). Quality of pelvic ring reduction was determined on postoperative radiographs as described by Matta, Sagi and Keshishyan/Lefaivre.

RESULTS

Clinical outcome at 6 months as measured by the Majeed and the Timed Up & Go correlated moderately with Keshishyan/Lefaivre's pelvic asymmetry value (Pearson R: -0.520 and 0.585, p ≤ 0.003) and the pelvic deformity index (-0.527 and 0.503, p ≤ 0.004). There was a weak correlation between the Timed Up & Go and the radiographic grading system as described by Matta/Tournetta at 6 months (0.408, p = 0.023) and at last follow-up (0.380, p = 0.035).

CONCLUSIONS

This study showed a moderate correlation of the clinical outcome at 6 months with postoperative quality of radiographic reduction when measured with the method described by Keshishyan and Lefaivre. Although having only descriptive value due to the small cohort, our findings underline the importance of anatomic reduction and restoration of pelvic symmetry in patients with pelvic trauma. Future studies with more patients and more investigators are required and reliability and validity of functional outcome scores needs to be further assessed to predict outcome in patient with fractures of the pelvic ring.

LEVEL OF EVIDENCE

Level IV (case series).

Intra- and interrater reliabilities and a method comparison of 2D and 3D techniques in cadavers to determine sacroiliac screw loosening

Sacroiliac (SI) screw loosening may indicate persistent instability, non-union and contribute to pain. Yet, there is no reliable objective measurement technique to detect and monitor SI screw loosening. In 9 cadaveric pelvises one of two SI screw was turned back approximately 20 mm and subsequently assessed by optical measurement, fluoroscopy and a 3D scan using an image intensifier. CTs were segmented and a contour-based registration of the 3D models and the fluoroscopies was performed to measure SI backing out (X-ray module). Three independent observers performed measurements with three repetitions. Deviation of the measurement techniques to the 3D scan, intra- and interrater reliabilities and method equivalence to the 3D scan were assessed. The X-ray module and two fluoroscopic measurement techniques yielded a difference less than 5 mm compared to the 3D scan and equivalence to the 3D scan. Intrarater reliability was for two observers and almost all techniques very good. Three fluoroscopic measurement techniques and optical measurements displayed a very good interrater reliability. The 3D scan and X-ray module yielded the most precise values for SI screw loosening but only the fluoroscopic measurement of the inlet lateral loosening displayed a good reliability and equivalence to the 3D scan.

Combined Pelvic Ring Disruption and Acetabular Fracture: Outcomes Using a Sequential Reduction Protocol and an Anterior Subcutaneous Pelvic Fixator (INFIX)

OBJECTIVE

The purposes of this article were to (1) compare our combined pelvic ring and acetabular fracture patients' rate of mortality and Injury Severity Score (ISS) to those of patients with isolated injuries at our center and to those with combined injuries as reported in the literature, (2) describe our treatment algorithm using the INFIX for these combination injuries, and (3) report our patients' radiographic and functional outcomes.

DESIGN

Retrospective IRB-approved case series and literature review.

SETTING

US Level 1 Trauma Center.

PATIENTS/PARTICIPANTS

Thousand six hundred ninety-seven with acetabular or pelvic ring injury, 174 patients with combination pelvic ring acetabular injuries, and 39 patients with 41 acetabular injuries treated with a surgical protocol.

INTERVENTION

Pelvic ring reduction using INFIX and posterior fixation followed by acetabular reduction fixation. Anterior injury fixed with INFIX.

MAIN OUTCOME

Mortality, ISS, pelvic reduction by Keshishyan index, acetabular reduction by the Matta criteria, and functional outcome by the Majeed score.

RESULTS

Mortality was 5.7% and ISS was 12.5 for 174 combined injury patients. In the 39 patients with 41 injuries, excellent pelvic reduction was found in 39, and acetabular reduction was anatomic in 25 (61%), imperfect in 12 (29%), and poor in 4 (10%). Clinically 78% of the patients had good or excellent outcome and 22% had a fair or poor outcome. Nonanatomic acetabular reduction, persistent sciatic nerve palsy, and heterotopic ossification associated with poor clinical outcome.

CONCLUSIONS

Our treatment protocol resulted in excellent pelvic reduction, anatomic acetabular reduction in 61% of patients, and 78% good to excellent clinical outcome.

LEVEL OF EVIDENCE

Case series Level IV.

Low-dose CT of postoperative pelvic fractures: a comparison with radiography

BACKGROUND

Computed tomography (CT) is superior to conventional radiography (CR) for assessing internal fixation of pelvic fractures, but with a higher radiation exposure. Low-dose CT (LDCT) could possibly have a sufficient diagnostic accuracy but with a lower radiation dose.

PURPOSE

To compare postoperative diagnostic accuracy of LDCT and CR after open reduction and internal fixation of pelvic fracture.

MATERIAL AND METHODS

Twenty-one patients were examined with LDCT and CR 0-9 days after surgery. The examinations were reviewed by two musculoskeletal radiologists. Hardware, degree of fracture reduction, image quality, and reviewing time were assessed, and effective radiation dose was calculated. Inter-reader agreement was calculated.

RESULTS

LDCT was significantly better than CR in determining whether hardware positioning was assessable ( P < 0.001). Acetabular congruence was assessable in all fractured patients with LDCT. In 12 of the 32 assessments with CR of patients with an acetabular fracture, joint congruence was not assessable due to overlapping hardware ( P = 0.001). Image quality was significantly higher for LDCT. Median time to review was 240 s for LDCT compared to 180 s for CR. Effective dose was 0.79 mSv for LDCT compared to 0.32 mSv for CR ( P < 0.001).

CONCLUSION

LDCT is more reliable than CR in assessing hardware position and fracture reduction. Joint congruency is sometimes not possible to assess with CR, due to overlapping hardware. The image quality is higher, but also the effective dose, with LDCT than with CR.

Anterior Subcutaneous Internal Pelvic Fixation/INFIX: A Systemic Review

INTRODUCTION

The purpose of this article is to review the available literature on anterior subcutaneous internal pelvic fixation (ASIPF) to identify indications, clinical and radiographic outcomes, and compare these with alternative fixation methods.

METHODS

Using the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, a systematic search on PubMed and Google Scholar was performed. Articles included were in the English language or English translations and published between 2007 and 2018. Studies included were appraised with narrative data synthesis.

RESULTS

Twenty-five articles with 496 patients were included. These included 17 case series, with 3 case reports reporting adverse events.

CONCLUSIONS

ASIPF and the appropriate posterior fixation resulted in healing of pelvic ring injuries in 99.5% of cases. Indications include unstable pelvic ring injuries with the appropriate posterior fixation. Radiographic parameters and outcome measures were infrequently reported. ASIPF is a valuable tool for reduction and fixation in unstable pelvic ring injuries. Complications include lateral femoral cutaneous nerve irritation (26.3%); heterotopic ossification (36%); infection (3%); and femoral nerve palsy (1%), which is likely related to placing the bar and screws too deep.

[Quantification of treatment success for geriatric sacral fractures]

BACKGROUND

Geriatric sacral fractures represent an independent fracture entity of increasing incidence and growing socioeconomic relevance. The goals of treatment are very different to those in younger patients with high-energy pelvic fractures. Hence, new outcome measurement instruments are required in order to assess the success of treatment.

OBJECTIVE

Literature review summarizing existing concepts and providing an overview of outcome measurement instruments for geriatric sacral fractures.

METHODS

Narrative review article based on an analysis of the German and English-speaking literature from the last 10 years.

RESULTS

Geriatric sacral fractures result in impaired mobility, increased physical and social loss of dependency and increased morbidity and mortality rates. There is a lack of standardized specific assessment procedures for functional outcome measurement after geriatric sacral fractures. Until these are developed and validated, a parallel acquisition of mortality, the timed up and go test, the Oswestry disability index (ODI) and a generic healthcare questionnaire score (SF-36, EQ-5D) seem to be most suitable.

CONCLUSION

At present our knowledge about the natural course of geriatric sacral fractures is limited by the lack of well-validated instruments to measure functional and radiographic outcomes. This has to be considered when evaluating the success of new treatment options for these patients. Future studies should validate existing scores for this population and develop new specific outcome instruments.

Early Experience with Reduction of Unstable Pelvic Fracture Using a Computer-Aided Reduction Frame

Purpose

The optimal closed reduction technique for unstable pelvic fractures remains controversial. The purpose of this study is to verify the effectiveness and report early experiences with the reduction of unstable pelvic fractures using a computer-aided pelvic reduction frame.

Methods

From January 2015 to August 2016, a total of 10 patients with unilateral unstable pelvic fractures were included in this study. The surgical reduction procedure was based on the protocol of the computer-aided pelvic reduction frame that we proposed in a previous work. The quality of the reductions achieved using this system was evaluated with residual translational and rotational differences between the actual and virtual reduction positions of pelvis. The duration of the operation was recorded for quality control.

Results

The mean times required to set up the frame, to complete the virtual surgery simulation, and to reduce the unstable pelvic fractures were 10.3, 20.9, and 7.5 min, respectively. The maximum residual translational and rotational displacements were less than 6.5 mm and 3.71 degrees, respectively.

Conclusions

This computer-aided reduction frame can be a useful tool for the speedy and accurate reduction of unstable pelvic fractures. Further clinical studies should be conducted with larger patient samples to verify its safety and efficacy.

ASSOCIATED POSTERIOR PELVIC INJURY PATTERNS IN TRANSVERSE-ORIENTED ACETABULAR FRACTURE

Objective:

Our study analyzed the incidence of posterior pelvic injury patterns and their influence on the surgical treatment of transverse-oriented acetabular fractures .

Methods:

Fifty-one transverse-oriented acetabular fracture cases admitted between 1999 and 2013 were evaluated retrospectively. Comparative studies were performed for groups organized by acetabular fracture type, degree of sacroiliac separation, and postoperative reduction quality .

Results:

Associated posterior pelvic injuries were found in 34 (66.7%) of the 51 patients. There were 32 sacroiliac separations in the 34 patients with associated posterior pelvic injury, and ipsilateral sacroiliac separations were more frequent in this subgroup. Measurements guided by computerized tomography showed that 16 sacroiliac separations were ≤0.5 cm (mean=0.43±0.14 cm), 10 were 0.5-1 cm (mean=0.73±0.17 cm), and the remaining 6 were >1 cm (mean=1.55±0.15 cm). In the group of 34 patients with associated posterior pelvic injury, acetabular reduction was anatomic in 19 (55.9%) patients, imperfect in 10 (29.4%) patients, and poor in 5 (14.7%) patients. For isolated acetabular fractures, reduction rates were as follows: 12 (70.6%) anatomic, 3 (17.6%) imperfect, and 2 (11.8%) poor. The rate of anatomic reduction was significantly higher when sacroiliac separation was ≤0.5 cm (p=0.027) .

Conclusion:

Associated posterior pelvic injuries, especially ipsilateral sacroiliac joint separation, accompany most transverse-oriented acetabular fractures and may influence the quality of acetabular reduction. Level of Evidence III, Therapeutic Studies Investigating the Results of Treatment.

Early Postoperative Displacement of Combined Pelvic Ring Injury With Acetabular Fracture

Combined pelvic ring and acetabular injuries present a management challenge. The literature on this topic is scarce, with few outcomes studies available. This retrospective study assessed whether the incidence of postoperative displacement and loss of reduction is higher with combined injuries compared with isolated pelvic ring injuries and isolated acetabular fractures. The charts and radiographs of 33 patients with combined pelvic ring and acetabular fractures treated operatively during a 7-year period at a single institution were reviewed. Pelvic ring and acetabular displacements were measured during the early postoperative period and compared with final follow-up measurements (minimum 5 months after surgery). Measurements also were compared with those from isolated pelvic ring fractures (n=33) and isolated acetabular fractures (n=33). Groups were matched for injury pattern and were propensity-matched by age and Injury Severity Score. Patients with combined injuries and patients with isolated pelvic ring injuries had similar initial pelvic ring reductions on anteroposterior and outlet view radiographs. By final follow-up, the combined injury group had experienced significant additional pelvic ring displacement. The presence of combined injury was an independent risk factor for postoperative pelvic ring displacement. Initial postoperative acetabular displacement was higher in the combined injury group compared with the isolated acetabular fracture group (2.6±1.8 vs 1.1±1.1 mm). By final followup, apparent displacement decreased significantly for both groups. Patients with combined pelvic ring and acetabular fractures were more likely to have poorer acetabular reduction and additional displacement of the pelvic ring component during the postoperative period compared with patients with isolated injuries. [Orthopedics. 2017; 40(3):163-168.].

Midterm Radiographic and Functional Outcomes of the Anterior Subcutaneous Internal Pelvic Fixator (INFIX) for Pelvic Ring Injuries

OBJECTIVE

To describe our experience using the anterior internal pelvic fixator (INFIX) for treating pelvic ring injuries.

DESIGN

Case Series.

SETTING

Level 1 Trauma Center.

PATIENTS

Eighty-three patients with pelvic ring injuries were treated with INFIX. Follow-up average was 35 months (range 12-80.33).

INTERVENTION

Surgical treatment of pelvic ring injuries included reduction, appropriate posterior fixation, and INFIX placement.

OUTCOME MEASUREMENTS

Reduction using the pelvic deformity index and pubic symphysis widening, Majeed functional scores, complications; infection, implant failure, heterotopic ossification (HO), nerve injury, and pain.

RESULTS

All patients healed in an appropriate time frame (full weight bearing 12 weeks postoperation). The average pelvic deformity index reduction (injury = 0.0420 ± 0.0412, latest FU = 0.0254 ± 0.0243) was 39.58%. The average reduction of pubic symphysis injuries was 56.92%. The average Majeed score of patients at latest follow-up was 78.77 (range 47-100). Complications were 3 infections, 1 case of implant failure, 2 cases implantation too deep, 7 cases of lateral femoral cutaneous nerve irritation, and 3 cases of pain associated with the device. HO was seen in >50% of the patients, correlated with increased age (P < 0.007), injury severity score (P < 0.05) but only 1 case was symptomatic.

CONCLUSIONS

The pelvic injuries had good functional and radiological outcomes with INFIX and the appropriate posterior fixation. The downside is removal requiring a second anesthetic, there is a learning curve, HO often occurs, the lateral femoral cutaneous nerve may get irritated which often resolves once the implants are removed. Surgery-specific implants need to be developed.

LEVEL OF EVIDENCE

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

Radiographic Measurement of Displacement in Acetabular Fractures: A Systematic Review of the Literature

OBJECTIVES

To report methods of measurement of radiographic displacement and radiographic outcomes in acetabular fractures described in the literature.

METHODS

A systematic review of the English literature was performed using EMBASE and Medline in August 2014. Inclusion criteria were studies of operatively treated acetabular fractures in adults with acute (<6 weeks) open reduction and internal fixation that reported radiographic outcomes. Exclusion criteria included case series with <10 patients, fractures managed >6 weeks from injury, acute total hip arthroplasty, periprosthetic fractures, time frame of radiographic outcomes not stated, missing radiographic outcome data, and non-English language articles. Basic information collected included journal, author, year published, number of fractures, and fracture types. Specific data collected included radiographic outcome data, method of measuring radiographic displacement, and methods of interpreting or categorizing radiographic outcomes.

DATA SYNTHESIS

The number of reproducible radiographic measurement techniques (2/64) and previously described radiographic interpretation methods (4) were recorded. One radiographic reduction grading criterion (Matta) was used nearly universally in articles that used previously described criteria. Overall, 70% of articles using this criteria documented anatomic reductions.

CONCLUSIONS

The current standard of measuring radiographic displacement in publications dealing with acetabulum fractures almost universally lacks basic description, making further scientific rigor, such as testing reproducibility, impossible. Further work is necessary to standardize radiographic measurement techniques, test their reproducibility, and qualify their validity or determine which measurements are important to clinical outcomes.

LEVEL OF EVIDENCE

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

Pelvic ring injuries: Emergency assessment and management

Pelvic ring injuries are associated with significant morbidity and mortality. Understanding the anatomy of the pelvic ring is essential for accurate diagnosis and treatment. A systematic approach taking into account the mechanism of injury, physical examination, and radiographic assessment is important to quickly identify unstable pelvic disruptions and associated injuries. Because the pelvis is a ring structure, isolated pubic rami fractures on plain radiographs are unusual and should warrant careful evaluation for posterior pelvic disruption with computed tomography. Hemorrhagic shock can occur in about 10% of pelvic ring injuries. Immediate recognition and treatment of this life-threatening condition is critical in emergency management. In addition to fluid resuscitation and blood transfusion, circumferential wrapping, angiographic embolization, laparotomy with pelvic packing, and external fixation can be important life-saving adjuncts in the setting of hemodynamic instability.