The pathological anatomy of Malgaigne fracture-dislocations of the pelvis

Surgical stabilisation in equivocal pelvic ring injuries - Into the grey zone

Pelvic ring injuries comprise a spectrum of bony, ligamentous and muscular injuries, described by several common classification systems. However, the majority of injuries lie in areas of intermediate severity, where complexity and variable nature make it extremely hard to define in detail. This fact and associated injuries make it extremely difficult to conduct randomised control trials, with purpose to direct treatment guidelines. Thus, special interest and expertise are required by pelvic trauma surgeons, while surgical indications and fixation methods rely on their experience, at least in part. Namely, a significant grey zone of indication exists. As fixation methods evolve, specifically percutaneous fixation using osseous fixation pathways, some injuries in which morbidity bound with surgical fixation was considered too high relative to its benefits, may be considered eligible for surgical treatment nowadays. Moreover, due to significant progress in the treatment of the acute polytrauma casualties, the survival rate increased over the years, emphasizing the effect of long-term morbidity and functional outcome of pelvic ring injuries. The purpose of this manuscript is to describe the equivocal areas of controversies, hence "the grey zone", and to provide the readership with up-to-date published data. We aimed to collect and detail clinical and radiological clues in the diagnosis of intermediate unstable anterior-posterior compression and lateral compression injuries, and for the selection of treatment methods and sequence. Recent publications have provided some insights into specific injury features that are correlated with increased chance of instability, pain and delay in ambulation. Specific focus is given to the utility of examination under anaesthesia in selected cases. Other publications surveyed the shared experience of pelvic trauma surgeons as for the classification, indication and treatment sequence of pelvic ring injuries. Although the data hasn't matured yet to a comprehensive treatment algorithm, it may serve clinicians well when making treatment decisions in the grey zone of pelvic ring injuries, and serve as a basis for future prospective studies.

Evolution of the AO Spine Sacral and Pelvic Classification System: a systematic review

OBJECTIVE

The purpose of this study was to describe the genesis of the AO Spine Sacral and Pelvic Classification System in the context of historical sacral and pelvic grading systems.

METHODS

A systematic search of MEDLINE, EMBASE, Google Scholar, and Cochrane databases was performed consistent with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines to identify all existing sacral and pelvic fracture classification systems.

RESULTS

A total of 49 articles were included in this review, comprising 23 pelvic classification systems and 17 sacral grading schemes. The AO Spine Sacral and Pelvic Classification System represents both the evolutionary product of these historical systems and a reinvention of classic concepts in 5 ways. First, the classification introduces fracture types in a graduated order of biomechanical stability while also taking into consideration the neurological status of patients. Second, the traditional belief that Denis central zone III fractures have the highest rate of neurological deficit is not supported because this subgroup often includes a broad spectrum of injuries ranging from a benign sagittally oriented undisplaced fracture to an unstable "U-type" fracture. Third, the 1990 Isler lumbosacral system is adopted in its original format to divide injuries based on their likelihood of affecting posterior pelvic or spinopelvic stability. Fourth, new discrete fracture subtypes are introduced and the importance of bilateral injuries is acknowledged. Last, this is the first integrated sacral and pelvic classification to date.

CONCLUSIONS

The AO Spine Sacral and Pelvic Classification is a universally applicable system that redefines and reorders historical fracture morphologies into a rational hierarchy. This is the first classification to simultaneously address the biomechanical stability of the posterior pelvic complex and spinopelvic stability, while also taking into consideration neurological status. Further high-quality controlled trials are required prior to the inclusion of this novel classification within a validated scoring system to guide the management of sacral and pelvic injuries.

An Automated Deep Learning Method for Tile AO/OTA Pelvic Fracture Severity Grading from Trauma whole-Body CT

Admission trauma whole-body CT is routinely employed as a first-line diagnostic tool for characterizing pelvic fracture severity. Tile AO/OTA grade based on the presence or absence of rotational and translational instability corresponds with need for interventions including massive transfusion and angioembolization. An automated method could be highly beneficial for point of care triage in this critical time-sensitive setting. A dataset of 373 trauma whole-body CTs collected from two busy level 1 trauma centers with consensus Tile AO/OTA grading by three trauma radiologists was used to train and test a triplanar parallel concatenated network incorporating orthogonal full-thickness multiplanar reformat (MPR) views as input with a ResNeXt-50 backbone. Input pelvic images were first derived using an automated registration and cropping technique. Performance of the network for classification of rotational and translational instability was compared with that of (1) an analogous triplanar architecture incorporating an LSTM RNN network, (2) a previously described 3D autoencoder-based method, and (3) grading by a fourth independent blinded radiologist with trauma expertise. Confusion matrix results were derived, anchored to peak Matthews correlation coefficient (MCC). Associations with clinical outcomes were determined using Fisher's exact test. The triplanar parallel concatenated method had the highest accuracies for discriminating translational and rotational instability (85% and 74%, respectively), with specificity, recall, and F1 score of 93.4%, 56.5%, and 0.63 for translational instability and 71.7%, 75.7%, and 0.77 for rotational instability. Accuracy of this method was equivalent to the single radiologist read for rotational instability (74.0% versus 76.7%, p = 0.40), but significantly higher for translational instability (85.0% versus 75.1, p = 0.0007). Mean inference time was < 0.1 s per test image. Translational instability determined with this method was associated with need for angioembolization and massive transfusion (p = 0.002-0.008). Saliency maps demonstrated that the network focused on the sacroiliac complex and pubic symphysis, in keeping with the AO/OTA grading paradigm. A multiview concatenated deep network leveraging 3D information from orthogonal thick-MPR images predicted rotationally and translationally unstable pelvic fractures with accuracy comparable to an independent reader with trauma radiology expertise. Model output demonstrated significant association with key clinical outcomes.

A biomechanics study on ligamentous injury in anterior-posterior compression type II pelvic injury

Background

Anterior-posterior compression (APC) type II pelvis fracture is caused by the destruction of pelvic ligaments. This study aims to explore ligaments injury in APC type II pelvic injury.

Method

Fourteen human cadaveric pelvis samples with sacrospinous ligament (SPL), sacrotuberous ligament (SBL), anterior sacroiliac ligament (ASL), and partial bone retaining unilaterally were acquired for this study. They were randomly divided into hemipelvis restricted and unrestricted groups. We recorded the separation distance of the pubic symphysis and anterior sacroiliac joint, external rotation angle, and force when ASL ruptured. We observed the external rotation damage to the pelvic bone and ligaments.

Result

When ASL failed, there was no significant difference in pubic symphysis separation (28.6 ± 8.4 mm to 23.6 ± 8.2 mm, P = 0.11) and anterior sacroiliac joint separation (11.4 ± 3.8 mm to 9.7 ± 3.9 mm, P = 0.30) between restricted and unrestricted groups. The external rotation angle (33.9 ± 5.5° to 48.9 ± 5.2°, P < 0.01) and force (553.9 ± 82.6 N to 756.6 ± 41.4 N, P < 0.01) were significantly different. Pubic symphysis separation between two groups ranged from 14 to 40 mm. In the restricted group, both SBL and SPL were injured. SPL ruptured first, and then SBL and the interosseous sacroiliac ligament were damaged while the posterior ligament remained unharmed. In the unrestricted group, interosseous sacroiliac ligament and posterior sacroiliac ligaments were damaged, while SBL and SPL were not. When the ASL, SBL, and SPL all failed, pubic symphysis and anterior sacroiliac joint separation between two groups increased significantly (from 28.6 ± 8.4 to 42.0 ± 7.6 mm, 11.4 ± 3.8 to 16.7 ± 4.2 mm respectively, all P < 0.05).

Conclusion

Pelvic external rotation injury is either hemipelvic restricted or unrestricted, which can result in different outcomes. When the ASL ruptures, the unrestricted group needs greater external rotation angle and force, without SBL or SPL injury, while both SBL and SPL were injured in another group. When ASL fails in two groups, pubic symphysis separation fluctuates considerably. Finally, when the ASL ruptures, SBL and SPL may be undamaged.

Posterior pelvic ring injury of straddle fractures: Incidence, fixation methods, and clinical outcomes

Straddle fracture, a superior and inferior ramus fracture of both sides, is generally treated conservatively. However, posterior pelvic ring injury is often associated with straddle fracture, leading to unstable pelvic bone fracture that requires surgical treatment. The present study reports the clinical and radiological outcomes of straddle fracture with posterior pelvic ring injury. This study included 73 patients (41 men, 32 women) with a straddle fracture injury. The injury mechanism, injury severity score (ISS), accompanying injuries, presence of posterior pelvic ring injury, and fixation methods for the pelvic fracture were analyzed, and outcomes were evaluated functionally and radiologically. Of the 73 patients, 56 (77%) had a posterior pelvic ring injury and 7 died. In 43 patients, the posterior pelvic ring injuries constituted unstable pelvic injury and were treated surgically. The fixation method was determined based on the severity of the posterior pelvic injury. The patients' mean ISS was 24.7 points. Radiological evaluation of surgical outcomes in 43 patients revealed the outcomes as anatomic in 20, nearly anatomic in 14, moderate in 5, and poor in 4, whereas functional evaluation revealed the outcomes as excellent in 21, good in 9, fair in 7, and poor in 6. Posterior pelvic ring fracture can accompany straddle fractures, which may lead to pelvic injury instability. Thus, special attention is required for patients with a straddle fracture.

Pelvic fractures: experience of pelvic ring fractures at a major trauma centre

In this review, we discuss the imaging classification of pelvic ring fractures in the context of our experience of reporting trauma computed tomography (CT) in a major trauma centre. Pelvic ring fractures are potentially significant injuries with risk of significant haemorrhage and morbidity. This review details the use of classification systems in determining the mechanism and severity of injury, with discussion of the features of the Young and Burgess classification system. We demonstrate the different types of pelvic ring fracture with examples from trauma CT, and with reference to the distribution and frequency of these injuries in trauma patients. This review will allow the reader to assess trauma CT for significant pelvic ring injury and identify features of instability.

Vertical shear pelvic injury: evaluation, management, and fixation strategies

Vertical shear pelvic ring fractures are rare and account for less than 1% of all fractures. Unlike severely displaced antero-posterior compression and lateral compression pelvic fractures, patients' mortality is lower. Nevertheless, patients must be managed acutely using well-defined ATLS protocols and institution-specific protocols for haemodynamically unstable pelvic ring fractures. The definitive treatment of vertical shear pelvic fractures is however more controversial with a paucity of literature to recommend the ideal reduction and fixation strategy. While the majority of injuries can be reduced and fixed in a closed manner, orthopaedic traumatologists should be familiar with the contraindications to those techniques as well as options such as tension band plating and lumbo pelvic fixation. Our paper reviews the acute management, associated injuries and definitive reduction and fixation strategies of vertical shear pelvic fractures. In addition, we propose a treatment algorithm for the selection of the most appropriate fixation technique.

Total hip arthroplasty via the direct anterior approach with Kerboull-type acetabular reinforcement device for an elderly female with factor XI deficiency

We present a case of successful and uncomplicated total hip arthroplasty with an acetabular reinforcement device in an elderly patient with hip osteoarthritis already diagnosed with factor XI deficiency, which is a very rare bleeding disorder and at high risk of post-operative haemorrhage, and it poses a substantial challenge to surgeons as a consequence of the specific risks of infection and fixation failure. Moreover, bone fragility in elderly patient increases potential risk of adverse event. Fresh frozen plasma was used to supplement factor XI activity. Importantly, transfusion-transmitted disease such as having factor XI inhibitor was promptly surveyed prior to the supplement since the patient had previous history of the administration of fresh frozen plasma. Under prompt and effective peri-operative haemostasis, rigid implant fixation and rigorous attention to the prevention of infection seem to achieve the best possible outcomes for elderly patients with a bleeding disorder undergoing total hip arthroplasty.

Pediatric pelvic ring injuries: How benign are they?

INTRODUCTION

With an incidence of less than 0.2% of all pediatric fractures, pelvic ring injuries are rare. Historically they were conservatively treated, but because malunion and long-term morbidity are associated with unstable injuries, a trend towards operative treatment can be observed. The purpose was to determine clinical and radiographic outcomes following these complex pediatric pelvic ring injuries.

PATIENTS AND METHODS

This Level IV retrospective analysis was completed at a private orthopaedic practice in association with a Level One teaching trauma center. There were 33 children with pelvic ring injuries with a mean age of 12.6 years (4-16) and an average follow up of 28.6 months (range 6-101). Injuries were 2 A2, 3 B1, 16 B2, 10 B3, and 2 C2 according to OTA/AO classification. Group 1 had 16 unstable, operatively treated injuries and Group 2 had 17 stable, non-operatively treated injuries. Radiographic deformity, leg length discrepancy, low back, and SI joint pain were evaluated.

RESULTS

For Group 1, 10 of 15 patients (67%) had a permanent ischial height difference >5mm compared to Group 2, in which 5 of 12 (42%) had an ischial height difference of >5mm. Group 1 had more pelvic asymmetry (12.3mm vs. 6.6mm) and ring width difference (6.9mm vs. 3.9mm) on final X-rays as compared to Group 2. Children with 5-10mm posterior sacral displacement had significantly more pain than children with 0-4mm displacement (p=0.034). Thirteen children (39%) had residual low back/SI joint pain; the rate was significantly higher in the Group 1 (3/17 vs. 10/16, p=0.008). In three (9%) children with 2 B2 and 1 B3 injury, leg length discrepancy between 5mm to 15mm occurred.

DISCUSSION AND CONCLUSION

In pediatric patients with pelvic ring injuries, radiographic deformity persisted and did not remodel. Pelvic ring deformity occurred more commonly with complex unstable ring injuries. The complex displaced injuries have higher rates of operative intervention, residual deformity, and low back and SI joint pain.

Pelvic ring injuries

Pelvic ring injuries exhibit a wide spectrum of severity; at times devastating with potentially serious immediate and long-term consequences. The anatomical and mechanistic basis of the injured pelvis is described. The non-operative and surgical management of pelvic ring disruption in the acute and definitive care settings is discussed. As emphasized here, basic principles, the mechanism of injury and pattern of instability help guide management.

Is Closed Reduction and Percutaneous Fixation of Unstable Posterior Ring Injuries as Accurate as Open Reduction and Internal Fixation?

OBJECTIVES

The objective of this retrospective review was to determine whether a closed reduction technique for unstable pelvic ring injuries is as accurate as an open technique.

DESIGN

Retrospective review.

SETTING

Two academic Level 1 trauma centers.

PATIENTS/PARTICIPANTS

We reviewed the records of 113 patients who had unilateral unstable pelvic ring injuries (Bucholz type 3, OTA type 61-C1) treated with closed reduction and percutaneous fixation (CRPF) or open reduction with internal fixation (ORIF).

INTERVENTION

Sixty patients were treated at one institution with open reduction and percutaneous iliosacral screw fixation. This involved prone positioning and a gluteus maximus sparing approach for direct visualization and reduction of the fracture. A second cohort of 53 patients was treated at a separate institution with closed reduction and percutaneous iliosacral screw fixation. This involved supine positioning and skeletal traction.

MAIN OUTCOME MEASURES

Preoperative and postoperative plain radiographs of the pelvis were reviewed and standardized measurements were made to compare quality of reduction.

RESULTS

We were able to measure displacement within 0.1 mm. Overall reduction quality was slightly better for the CRPF group. The largest average difference in postoperative displacement was seen at the iliac wing height on anteroposterior pelvis radiographs with 6.3 mm (range 0-19.6) in the ORIF group versus 1.9 mm (range 0-4.7) in the CRPF group.

CONCLUSIONS

The closed reduction technique described here is as effective as the ORIF technique in obtaining reduction of unstable pelvic ring injuries (Bucholz type 3, OTA type 61-C1).

LEVEL OF EVIDENCE

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

Orthopedic emergencies: a practical emergency department classification (US-VAGON) in pelvic fractures

Trauma is one of the leading causes of death before the age of 40 years and approximately 5% of patients with trauma who require hospital admission have pelvic fractures. This article updates the emergency department classification of pelvic fractures first described in 2000. This information is of practical value to emergency physicians in identifying the potential vascular, genitourinary, gastrointestinal, orthopedic, and neurologic complications and further assists them in the initial evaluation and treatment of patients with pelvic fractures.

Drug-releasing implants: current progress, challenges and perspectives

This review presents the different types and concepts of drug-releasing implants using new nanomaterials and nanotechnology-based devices.

What is the infection rate of the posterior approach to type C pelvic injuries?

BACKGROUND

Pelvic ring injuries with complete disruption of the posterior pelvis (AO/OTA Type C) benefit from reduction and stabilization. Open reduction in early reports had high infectious complications and many surgeons began using closed reduction and percutaneous fixation. Multiple smaller studies have reported low infection rates after a posterior approach, but these rates are not confirmed in larger series of diverse fractures.

QUESTIONS/PURPOSES

We therefore determined (1) the incidence of surgical site infectious complications after a posterior approach to the pelvis; and (2) whether secondary procedures other than surgical débridement are necessary as a result of the approach-related complications.

METHODS

We retrospectively reviewed all 236 patients (268 surgical approaches) with C type injuries treated with a posterior approach at six institutions before 1998 and at one institution from 1998 to 2005. Posterior injuries were classified anatomically as described by Letournel and the AO/OTA system. We recorded wound complications after surgery.

RESULTS

Surgical site infection occurred in eight of the 236 patients (3.4%) in the multicenter analysis. Treatment consisted of surgical débridement, wound closure, and antibiotics. No patients required soft tissue reconstruction as a result of the approach or infection.

CONCLUSION

Our data suggest with proper patient selection and the described surgical technique, there should be minimal risk for catastrophic wound complications or high infection rates as reported by others.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Internal fixation of symphyseal disruption resulting from childbirth

OBJECTIVES

To investigate the clinical and radiographic results after operative treatment of complete symphyseal disruption resulting from childbirth and to evaluate residual pain and implant failure in relation to the timing of surgery.

DESIGN

Retrospective study.

SETTING

Tertiary pelvis and acetabulum care unit at a general hospital.

PATIENTS

Ten consecutive women with complete symphysis disruption associated with childbirth were included from a database of 603 patients with pelvic fracture. No patients with this diagnosis were excluded. All patients were followed until clinical healing of the symphysis or union of the fusion.

INTERVENTION

Open reduction and internal fixation in acute (less than 2 weeks from childbirth, four patients) and after failed nonoperative treatment in subacute cases (2 weeks to 6 months after childbirth, three patients). Fusion of the symphysis with iliac crest bone graft and plate fixation after failed nonoperative treatment in chronic cases (greater than 6 months, three patients).

MAIN OUTCOME MEASUREMENT

Analyzed variables included the Lindahl score, maintenance of postoperative reduction, implant failure, malunion, and necessity of reoperation.

RESULTS

Mean age of the patients was 32 years (range, 24-37 years). Mean follow up was 29 months (range, 5-139 months). The mean postoperative Lindahl score was 68 ± 14.6 points (range, 38-80 points). There were three excellent, four good, two fair, and one poor result. Fair or poor results occurred in one subacute and two chronic cases. There were two revision surgeries. One patient underwent implant removal resulting from dyspareunia 3.1 years postoperatively. One subacute patient had conversion to symphyseal fusion after implant failure as a result of a fall 11 years after index surgery. Major complications occurred in two and minor complications in three patients. Radiographic loosening of implants was observed in all subacute cases. All fusions healed and symptoms improved at last follow up.

CONCLUSIONS

Operative management significantly improved the functional outcomes of all three subgroups and can be an acceptable treatment option for labor-induced complete symphysis pubis disruption.

Anterior sacroiliac dislocation

Although much has been written on the evaluation and management of pelvic ring injuries, only a single case of anterior sacroiliac joint dislocation exists in the literature and was reported in 1976. This article describes 2 additional cases, 1 of a pure anterior sacroiliac dislocation in a 25-year-old man, and 1 of an anterior sacroiliac fracture-dislocation in an 18-year-old man, each treated by a different orthopedic traumatologist at neighboring trauma centers. Both cases were the result of high-energy trauma, and both patients had significant complications resulting from severity of their injuries, including wound dehiscence and causalgia in 1 case and persistent L5-S1 paresthesias and paresis in the other. Closed reduction can be attempted, but in our experience was unsuccessful even with the use of external fixation pins for leverage. We recommend open reduction by an orthopedic traumatologist who will perform definitive fixation. The decision to use an anterior external fixation frame to assist during the patient's resuscitation should be based on the patient's hemodynamic status and concomitant injuries. Despite a high complication rate, operative intervention can return patients to a functional level with minimal residual pain.

Stress radiographs in orthopaedic surgery

Stress radiographs are useful in determining the amount of ligamentous laxity present following trauma. The results may be helpful in determining diagnosis, surgical indications, and the type and timing of rehabilitation. Some techniques for obtaining stress radiographs involve specific patient positioning or manually applied force; others require use of a particular testing device. Stress radiographs may be obtained for a variety of anatomic areas and joints. The parameters that define abnormality on stress radiographs should be compared with those of clinical findings. The use of common and novel methods to obtain stress radiographs has led to improved identification and diagnosis of many orthopaedic pathologies. Some of these techniques have been developed with the aim of reducing patient discomfort or minimizing the clinician's exposure to radiation.

The anterior dislocation of the sacroiliac joint: a report of four cases and review of the literature and treatment algorism

Pelvic fractures are an uncommon injury in pediatric trauma patients, but the morbidity and mortality associated with these injuries can be profound. Of the posterior pelvic ring disruptions, the posterior dislocation of sacroiliac joint, which is the traditional dislocation of the sacroiliac joint, occurs in most incidences of pediatric trauma patients. There are few reports, however, on the "anterior" dislocation of sacroiliac joint, in which the ilium dislocates anterior to the sacrum and often combines with symphyseal diastasis and fractures of pubic rami and ilia. The distinct fracture-dislocation of sacroiliac joint is a subtype of completed posterior pelvic fracture. Literature review contains little information about such type of dislocation. We present four cases of pediatric trauma patients with the "anterior" dislocation of sacroiliac joint. After a thorough literature review of existing classification of pelvic fractures, we name it as the anterior dislocation of sacroiliac joint.

Skeletal deformity after anterior external fixation of the pelvis

OBJECTIVE

To study the deformity of acutely injured unstable pelves before and after emergent application of an anterior external fixator.

DESIGN

Retrospective.

SETTING

Large pelvic fracture referral practice.

PATIENTS

Eleven of 151 patients referred to our institution after emergent application of an external fixator by the referring orthopaedist before transfer who were hemodynamically unstable and had a mechanically unstable pelvic injury with pre-external fixator radiographs and post-external fixator radiographs adequate to determine pelvic deformity.

MAIN OUTCOME MEASUREMENTS

We reviewed all available radiographs both before and after placement of the external fixator (the anterior-posterior, inlet, outlet, and computed tomography), determining whether the external fixator improved or worsened the deformity.

RESULTS

Although many deformities existed, we found that application of an anterior frame consistently worsened this deformity. Seven of the 11 patients (64%) had worsening of the posterior cephalad translation or posterior diastasis despite apparent improvement anteriorly on the anterior-posterior radiograph. "External fixator deformity," defined as increased flexion and/or internal rotation of the hemipelvis, also occurred in 8 of 11 patients (73%). After placement of the external fixator, all patients displayed greater than 1 cm of either posterior cephalad translation or posterior diastasis (average 3.4 cm, range 1.3-4.6 cm).

CONCLUSIONS

Due to the forces placed on the pelvis during application of an anterior external fixator by the surgeon, an external fixator deformity may occur (flexed and internally rotated hemipelvis). Furthermore, most patients had an increase in posterior cephalad translation or posterior diastasis with placement of an external fixator. The surgeon should be aware of the potential of increasing the pelvic deformity when applying an emergent anterior external fixator.

Single-leg-stance radiographs in the diagnosis of pelvic instability

BACKGROUND

In the nonacute setting, the diagnosis of pelvic instability is difficult. Patients who present with pelvic pain may have underlying instability. The purpose of the present study was to report the effectiveness of single-leg-stance radiographs in the diagnosis of pelvic instability in a consecutive series of patients presenting with pelvic pain.

METHODS

Thirty-eight consecutive patients (twenty-four women and fourteen men) ranging in age from eighteen to seventy-eight years who presented with pelvic pain and a history of injury (twenty-seven), childbirth (seven [four primiparous and three multiparous]), or osteopenia (four) were evaluated with a visual analog scale pain score and a standard series of radiographs in an attempt to identify pelvic instability. The average time from the onset of symptoms to the evaluation was forty-one months (range, six weeks to twenty-seven years). Each patient was evaluated with supine anteroposterior, inlet, and outlet pelvic radiographs; a standing anteroposterior pelvic radiograph; and two single-leg-standing pelvic radiographs (one with the patient standing on the left leg and one with the patient standing on the right leg). A positive finding was defined as >or=0.5 cm of vertical translation measured at the symphyseal bodies between the two single-leg-stance radiographs.

RESULTS

Of the thirty-eight patients, twenty-five demonstrated pelvic instability (average, 1.98 cm; range, 0.5 to 5 cm). With the numbers available, the average visual analog scale pain score for the patients with a stable pelvis was not significantly different from that for the patients with an unstable pelvis (6.4 +/- 2.9 compared with 7.3 +/- 1.9; p = 0.28).

CONCLUSIONS

Standing anteroposterior and single-leg-stance pelvic radiographs aid in the diagnosis of pelvic instability more effectively than do the standard three radiographs of the pelvis made in the supine position or a standing anteroposterior radiograph of the pelvis alone. Additional studies will be needed to correlate this instability with clinical symptoms.

LEVEL OF EVIDENCE

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

Pelvic ring disruptions: treatment modalities and analysis of outcomes

A systematic review of the English literature over the last 30 years was conducted in order to investigate the correlation of the clinical outcome of different types of pelvic ring injuries to the method of treatment. Three basic therapeutic approaches were analysed: non-operative treatment (group A), stabilisation of anterior pelvis (group B) and internal fixation of posterior pelvis (group C). Of 818 retrieved reports, 27 case series, with 28 groups of patients and 1,641 patients, met our inclusion criteria. The quality of the literature was evaluated using a structured questionnaire. Outcomes of the eligible studies were summarised by the medians of the reported results. Most of the component studies were of fair or poor quality. Certain radiological results (quality of reduction, malunion rates) were significantly better in group C. From the functional point of view only walking capacity was proved to be significantly better in the groups of operative treatment compared to the non-operative group.

Table-skeletal fixation as an adjunct to pelvic ring reduction

The reduction of displaced pelvic ring injuries remains a technical challenge, especially when treatment is delayed. A pelvic frame (Orthopaedic Systems Inc, Union City, California) provides a means of external skeletal fixation, rigidly stabilizing the intact hemipelvis to the operating room table. The fractured and displaced fragments can then be manipulated around the securely fixed uninjured hemipelvis, allowing the application of more directions and magnitudes of force for reduction maneuvers than allowed by the traditional means of pelvic reduction. The surgical technique and 1 case each of an acute fracture and pelvic nonunion/malunion are presented.

Auditing 655 Fatalities with Pelvic Fractures by Autopsy as a Basis to Evaluate Trauma Care

BACKGROUND

To determine the role of pelvic fractures in auditing mortality resulting from trauma.

STUDY DESIGN

This retrospective case-control study based on autopsy-evaluated circumstances of the deaths of patients with pelvic fractures.

RESULTS

Of 2,583 patients injured in motor-vehicle collisions, 655 (25.4%) constituted the pelvic fracture (PFx) group, and 1,928 (74.6%) constituted the control group. One-third of the PFx group's fatalities had an Injury Severity Score (ISS) of 75 and were not preventable. The PFx group had a substantially higher median ISS than the control group (50 versus 34; p < 0.0001). Four hundred fifty-four patients (69.3%) in the PFx group with ISS 16 to 74 had substantially higher rates of associated injuries. Nearly half of the PFx group patients with ISS <or= 74 had a potential cause of major hemorrhage other than pelvic fracture. Twenty-three (3.5%) deaths were directly attributable to pelvic fractures. Postinjury median survival time was 55 minutes for the PFx group and 100 minutes for the control group (p < 0.0001). The time limit for management of the patients with pelvic fractures was short, as 527 (81.5%) died in the first 6 hours. It was evident that the more severe the injuries were, the sooner the deaths occurred. Of 151 subjects who left the emergency department alive, 61.6% were subjected to operation and 48.3% to abdominal operation.

CONCLUSIONS

Pelvic fracture is an indicator of severe multiple trauma, but a small proportion of deaths are directly attributable to pelvic fracture. A method based on autopsy audited patients with pelvic fractures as a paradigm of injury revealed that pelvic fracture is an important injury to consider in auditing trauma care and indicated several issues that should be considered to reduce mortality.

Surgical management of transforaminal sacral fractures

Fourteen patients with transforaminal sacral fractures were treated with posterior iliosacral instrumentation. Patients were assessed in terms of surgical technique and functional results. A subjective functional scoring with a five-point scale was performed at the last follow-up. Activity pain, pain at rest, limping and patient satisfaction were evaluated. By considering symptom and satisfaction scores, subjective functional assessment revealed that ten patients had excellent results, two good and two moderate. There were no patients with poor functional outcome. The surgical technique is not a new concept. Combining sacral bar and pediculo-iliac fixation methods, provides vertical as well as horizontal stability and allows early weight bearing, the methods has many advantages. However, vertical and horizontal stabilities achieved by this technique may require further assessment with comparative biomechanical studies.

Soft tissue injuries associated with pelvic fractures

Significant soft tissue injuries often occur as part of high-energy injuries to the pelvis. These soft tissue injuries must be recognized and considered when implementing a treatment plan if complications are to be minimized. Vigilance in diagnosing open fractures must be maintained. Patients with these injuries must be managed aggressively, because they are at high risk for complications and death. Closed pelvic and acetabular fractures also may include soft tissue injury that requires special consideration. Careful evaluation and management of the soft tissues aids in determining appropriate techniques for reduction and fixation of the associated fractures.

Pelvic trauma in rapidly fatal motor vehicle accidents

OBJECTIVE

To study the incidence and nature of pelvic fractures in rapidly fatal automobile accidents.

DESIGN

Retrospective.

SETTING

County Medical Examiner's Office.

PATIENTS

The files of 255 consecutive motor vehicle accident fatalities examined at the Jefferson County Coroner/Medical Examiner's office (study period 1996-1998) were reviewed. We correlated this information with our previous findings, derived from a review of 392 such cases (study period 1994-1996).

RESULTS

Approximately 25% of decedents involved in rapidly fatal automobile accidents sustained pelvic fractures. In 93% of the cases, postmortem radiographs were available and suitable for scoring according to the Orthopaedic Trauma Association nomenclature. The distribution of pelvic fractures by type was type A, 16%; type B, 32%; and type C, 52%, with the most common pelvic fracture being type C1 (26%). Additionally, pedestrians and motorcyclists were twice as likely to sustain a pelvic fracture, and the severity of pelvic fracture type seemed to correlate with increasing speed of the automobile. No correlation between drug use or direction of impact and incidence or type of pelvic fracture was observed. Compared with published studies on survivors of automobile accidents, our data suggest that pelvic injuries may tend to be more severe in victims who do not survive to hospitalization.

CONCLUSIONS

Our data indicate that current estimates about the mortality of pelvic fractures may be faulty due to exclusion of victims who fail to survive to hospitalization. This series suggests that an appreciation of the full spectrum of pelvic ring disruptions requires collaboration between orthopaedic surgeons and forensic pathologists.

In vivo release of vancomycin from biodegradable beads

The current delivery system of antibiotics for the treatment of osteomyelitis uses polymethylmethacrylate (PMMA) beads as a local drug-release agent. The nonbiodegradable nature of the PMMA, however, necessitates a second operation to remove the beads. This article explores the alternative of using biodegradable polymers as antibiotic beads for a long-term drug release in vivo. To manufacture an antibiotic bead, lactide-glycolide copolymers were mixed with vancomycin. The mixture was compressed and sintered at 55 degrees C to form beads 8 mm in diameter. An in vivo animal model was proposed to characterize the elution rate of antibiotic over a 55-day period. Biodegradable beads released high concentrations of antibiotic (well above the breakpoint sensitivity concentration) in vivo for the period of time needed to treat bone infection; that is, 4-6 weeks. A bacterial inhibition test was also carried out to determine the relative activity of the released antibiotics. The diameter of the sample inhibition zone ranged from 8 to 18 mm, which is equivalent to 9.1 to 100% of relative activity. In addition, the antibiotic concentration of systemic blood was found to be very low. Antibiotic-impregnated biodegradable beads may have a potential role in the prevention and management of surgical infections.

Clinical effectiveness of the physical examination in diagnosis of posterior pelvic ring injuries

OBJECTIVE

To determine if physical examination (PE) of the posterior pelvis in awake and alert trauma patients with known pelvic ring injuries can accurately predict a potentially unstable posterior ring injury and guide the use of computed tomography (CT) more effectively.

DESIGN

Patients with pelvic fracture noted on anteroposterior (AP) pelvic radiographs were prospectively evaluated over a 21-month period. AP, inlet, and outlet radiographs as well as CT scans were obtained on all patients.

SETTING

Level I trauma center.

PATIENTS

Patients were excluded who had a Glasgow Coma Scale score less than or equal to 12, were unable to cooperate with a PE, were 12 years old or younger, or had concomitant acetabular fracture.

INTERVENTION

A focused PE protocol with emphasis on the posterior pelvis, including posterior palpation of the sacrum and sacroiliac joint, AP and lateral iliac wing compression, active hip range of motion, and a digital rectal examination. If an individual PE parameter resulted in tenderness, it was considered positive.

MAIN OUTCOME MEASUREMENTS

The 4 PE modalities were compared with CT scan results using sensitivity, specificity, negative predictive value, positive predictive value, likelihood ratio, and McNemar's test for discordant pairs.

RESULTS

The study group included 66 patients. Of patients, 49 (74%) had posterior pelvic injury diagnosed by CT scan. Of the patients with positive posterior CT scan findings, 48 (98%) had pain with posterior palpation. Sensitivity and specificity were 0.98 and 0.94, and the likelihood ratio was 16.3.

CONCLUSIONS

PE, specifically palpation of the posterior pelvis, in patients with pelvic fractures can accurately detect injuries of the posterior ring.

External fixators for pelvic fractures: comparison of the stiffness of current systems

We evaluated the stiffness of external fixation (EF) systems with a reproducible, standardized human pelvic replica of aluminum and perspex in which a type C pelvic ring injury was created. 12 EF systems were analyzed in 2 situations that necessarily occur during a walking cycle. Endpoints were defined as 15 mm of dislocation or tolerance of the maximum load in each situation. In the no weightbearing situation, all except 2 fixators failed; in the weightbearing situation, all fixators failed. Single bar systems performed better than frame configurations. Stability provided by any external fixator is low, and in the case of a type C pelvic ring injury, it is insufficient for patient mobilization and weightbearing. Single bar systems provide more stability than frames.

Improvement of external fixator performance in type C pelvic ring injuries by plating of the pubic symphysis: an experimental study on 12 external fixators

BACKGROUND

In an earlier study, we introduced a pelvic ring stability criterion for weightbearing stabilization. In a loading test, however, current external fixation systems alone did not meet this criterion. Internal fixation of the dorsal ring can significantly increase stability, but the condition of severely injured patients is often a contraindication for major surgery. The aim of this study is to optimize external pelvic ring fixation without dorsal ring stabilization to allow weightbearing in early mobilization of patients with unstable pelvic ring injuries.

METHODS

The stiffness of external fixation systems alone and in combination with one or two anterior plates was measured by using a pelvic replica with a type C pelvic ring injury. Endpoints were 15 mm of dislocation or tolerance of 560 N.

RESULTS

Addition of one plate at least doubles stiffness, whereas two-plate fixation results in at least a fourfold stiffer configuration. Frame configurations profit more than single-bar systems, and all but one system resist the weightbearing load after double-plating of the pubic symphysis.

CONCLUSION

The choice of double-plate fixation of the anterior ring in addition to external fixation results in weightbearing capacity.

Tobramycin-containing bone cement and systemic cefazolin in a one-stage revision. Treatment of infection in a rabbit model

The efficacy of tobramycin-containing bone cement with that of systemic cefazolin for treatment of infection in a one-stage revision model is compared. In addition, the value of detecting bacterial DNA after antibiotic treatment was investigated. An implant was inserted into the right tibia of rabbits after inoculation with Staphylococcus aureus. At 28 days, the implant was removed. Subsequently, either plain bone cement with or without systemic administration of cefazolin, or tobramycin-containing bone cement was injected into the medullary canal. The tibiae were cultured 14 days after revision (Day 42), and showed a significant decrease in bacterial counts for both antibiotic groups compared with the control group (p</=0.05). The rate of infection in the tobramycin-cement group was slightly higher (2/9) than in the cefazolin group (0/8), although the difference was not significant. Persistence of bacterial DNA after antibiotic treatment may be the result of delayed clearance of DNA and not a sign of active infection. This animal model shows that in a one-stage revision tobramycin-containing bone cement can reduce size and rate of infection, although systemic cefazolin may be more efficacious. Therefore, the use of antibiotic-containing bone cement combined with systemic antibiotic might provide optimal treatment.

Pelvis and hip joint injuries as a reconstructive factors in car-to-pedestrian accidents

The pelvic girdles of 371 pedestrian victims of road traffic accidents were evaluated during postmortem examinations. Additionally, 144 hip joints were opened. The pelvic injuries were found in 28% of the pedestrians hit exclusively in their upright position and 52% of the victims run over by a vehicle. The side of the body hit by a car was determined on the basis of the location of blood suffusions within the subcutaneous tissues and muscles of lower limbs as well as the character of injuries found in the knee and upper ankle joints. The findings were verified with the data from court records. It was shown that the injuries of the sacroiliac joints or vertical fractures of the posterior parts of iliac bones were useful parameters for determining the side (left or right) of the body hit by a vehicle. Moreover, it was found that a direct impact on the hip region was evidenced by the ipsilaterally localized fractures of the iliac ala, central hip fractures and intraosseous blood suffusions within the greater trochanter of the femur. The external dislocations of the hip joints (always) and bilateral injuries to the sacroiliac joints (usually) were observed in the victims run over by vehicles.

Sectional imaging anatomy: pelvic ring ligaments

The purpose of this article is to describe the complex anatomy of the pelvic ligaments. It uses schematics to display 10 color-coded ligaments in relation to the bony architecture. This atlas and the accompanying summary of the classification of pelvic ligamentous injuries is designed to encourage the use of magnetic resonance imaging in cases of pelvic ring trauma.

Comminuted fractures of the iliac wing

PURPOSE

Comminuted iliac fractures are uncommon and difficult to treat. The purpose of this study is to further delineate the fractures, to present a management protocol, and to evaluate the results of treatment.

DESIGN

Retrospective clinical study.

SETTING

Level one trauma center at Harborview Medical Center.

PATIENTS

During a sixty-eight-month period, 695 patients with pelvic ring disruptions were treated at a level one trauma center. Thirteen (1.9%) of these patients had a severely comminuted iliac fracture. All patients were men, ranging in age from twenty to eighty years (mean, 38 years). These patients were polytraumatized and had a mean Injury Severity Score of 23. Eleven of the thirteen patients had severe iliac and flank degloving injuries. Five patients had open fractures, one with fecal contamination requiring diverting colostomy. Six patients with clinical signs of hemodynamic instability had local arterial injuries associated with their fractures. All five patients with extension of the fracture into the greater sciatic notch were found to have a local arterial injury on angiography. One patient had a lumbosacral plexopathy on the fractured side. Four patients had traumatic brain injuries.

INTERVENTION

All thirteen patients were treated operatively. Routine pelvic external fixation was not possible because of the iliac comminution. Stable internal fixation was accomplished by an anterior iliac surgical exposure using lag screw and plate combinations. The open wounds and degloving injuries were treated with irrigation, debridement, and closed suction drainage.

MAIN OUTCOME MEASUREMENTS

Healing and stability of fixation were assessed clinically and on pelvic radiographs.

RESULTS

Comminuted iliac fractures were divided into two patient groups, according to associated pelvic ring disruption. Follow-up evaluations were available for all patients at a mean of eighteen months after injury. There were no deaths. All of the fractures healed clinically and radiographically. In one patient, fecal contamination caused a polymicrobial wound infection, and this patient had an associated delay in union of the fracture. Another patient with an open fracture developed a deep wound infection. Both infections responded to local management and antibiotics. There were no complications associated with the degloving injuries.

CONCLUSIONS

Comminuted iliac fractures occur in two distinct patterns and are associated with numerous local injuries that complicate management. Management protocols should include early open reduction and stable internal fixation. Traumatic open wounds should not be closed primarily. Primary closure with closed suction drainage is effective in the management of associated degloving injuries. Extension of the fracture into the greater sciatic notch warrants further evaluation with pelvic angiography.

Emergency department evaluation and treatment of pelvic fractures

Pelvic fractures are associated with a high morbidity and mortality rate. This article reviews the anatomy of the pelvis, discusses fracture patterns commonly seen in patients with an injured pelvis, and proposes a new method of classifying pelvic fractures based on potential associated injuries. Finally, algorithms for the management of hemodynamically stable and unstable patients with pelvic fractures are presented.

Pelvic fractures: the golden hour

Major accident units should be able to apply standard treatment methods to control life threatening haemorrhage within the 'Golden Hour', as recommended by the ATLS guidelines. In this study all 31 major accident units in Scotland were examined to determine their ability to stabilize a pelvic fracture within this period. We found that only eight units could potentially stabilize a pelvis within 1 h. In eight other units no appropriate emergency treatment was available. We recommend that all units designated to receive multiple injuries should have a pelvic stabilization device as well as the training and expertise to use it.

Intrapelvic dislocation of the left hemipelvis as a complication of the pelvic "C" clamp: a case report and review

High-energy pelvic trauma, with posterior pelvic disruption, produces high morbidity and mortality rates. Part of the initial resuscitation has included an anterior external fixator to close the pelvic ring, thereby decreasing blood loss and reducing mortality. However, this technique has been found to be less efficacious in certain situations. This has stimulated an interest in alternative methods of stabilization, which has led to the recent development of the emergency pelvic "C" clamp. We present one of the potential pitfalls of this new device, discuss pertinent clinical and biomechanical studies, and offer suggestions regarding its use.

Evaluation of pelvic fractures. Clinical and radiologic

This article gives the orthopedic surgeon a framework to use during the initial evaluation of a patient with a pelvic fracture in the emergency room. The essential elements of the assessment of instability, both clinically and radiologically, are given in this article. Examples of the major patterns of instability are provided.

Assessment and management of pelvic fracture in the hemodynamically unstable patient

Hypotensive patients with pelvic ring injuries present a diagnostic and therapeutic challenge. This article reviews pelvic anatomy, the classification of pelvic injuries, and how to rapidly identify patients' unstable pelvic injuries. Current recommendations for the evaluation and treatment of these patients are reviewed.

Pelvic trauma imaging: a blinded comparison of computed tomography and roentgenograms

To determine the sensitivity for detecting pelvic pathology and instability, roentgenograms and computed tomographic (CT) scans from 59 patients with pelvic injuries that had been admitted to a Level I trauma center were randomly reviewed by a orthopedic surgeon blinded to the study. Normal control roentgenograms and CT scans were included to decrease observer bias. The anteroposterior (AP) roentgenogram detected 66% of all pelvic injuries, 78% of those involving the anterior ring, and 53% of those involving the posterior pelvic ring. The trauma CT scan, 10-mm axial images of the abdomen and pelvis, detected 86% of all pelvic injuries, and 78% of anterior ring and 93% of posterior ring injuries. The sensitivity for detecting pelvic instability from one plain film AP pelvis roentgenogram taken in a trauma room setting was 74%. Inlet and outlet views were 75% sensitive. Trauma CT scans were 93% sensitive and high-definition pelvic CT scans (5-mm pelvic cuts) yielded 100% sensitivity. The mechanism of injury could be ascertained with 73% sensitivity by plain films and with 79% sensitivity by inlet and outlet views; trauma CT scans were 96% and high-definition pelvic CT scans were 100% sensitive. When combined, the AP pelvis roentgenograms and trauma CT scans identified 96% of the injured structures and were 100% sensitive in determining injury force patterns and instability. The data suggested that a good quality AP pelvis roentgenogram in conjunction with a complete trauma CT scan of the abdomen/pelvis should identify both the injury mechanism and pelvic instability with a high degree of sensitivity.