Internal fixation of unstable pelvic ring injuries

Biomechanical comparison of standard iliosacral screw fixation to transsacral locked screw fixation in a type C zone II pelvic fracture model

OBJECTIVES

Iliosacral screw fixation into the first sacral body is a common method for pelvic ring fixation. However, this construct has been shown to be clinically unreliable for the percutaneous fixation of unstable Type C zone II vertically oriented sacral fractures with residual fracture site separation. The objective of this study was to biomechanically compare a locked transsacral construct versus the standard iliosacral construct in a Type C zone II sacral fracture model.

METHODS

A Type C pelvic ring injury was created in ten embalmed cadaver pelves by performing vertical osteotomies through zone II of the sacrum and the ipsilateral pubic rami. The sacrum was then reduced maintaining a 2 mm fracture gap. Five specimens were fixed using two 7.0-mm iliosacral screws into the S1 body; the other 5 were fixed using one 7.0-mm iliosacral screw and one 7.0-mm transsacral screw exiting the contralateral ilium with a nut placed on its end, creating a locked construct. Each pelvis underwent 100,000 cycles at 250 N and was then loaded to failure using a unilateral stance testing model. Vertical displacements at 25,000; 50,000; 75,000 and 100,000 cycles and failure force were recorded for each pelvis.

RESULTS

The locked transsacral construct performed significantly better than the iliosacral construct at all 4 measurement points (P = 0.009) and in force to failure (P value = 0.02).

CONCLUSIONS

Fixation of unstable zone II sacral fractures using the combination of an iliosacral screw and a locked transsacral screw resists deformation and withstands a greater force to failure as compared to fixation with 2 standard iliosacral screws. This locked transsacral construct may prove advantageous, especially when a percutaneous technique is used for a Type C zone II vertically oriented sacral fracture injury pattern, which can result in residual fracture site separation.

Mechanical comparison between lengthened and short sacroiliac screws in sacral fracture fixation: a finite element analysis

OBJECTIVE

To compare the stability of lengthened sacroiliac screw and standard sacroiliac screw for the treatment of unilateral vertical sacral fractures; to provide reference for clinical applications.

METHODS

A finite element model of Tile type C pelvic ring injury (unilateral Denis type II fracture of the sacrum) was produced. The unilateral sacral fractures were fixed with lengthened sacroiliac screw and sacroiliac screw in six different types of models respectively. The translation and angle displacement of the superior surface of the sacrum (in standing position on both feet) were measured and compared.

RESULTS

The stability of one lengthened sacroiliac screw fixation in S1 or S2 segment is superior to that of one sacroiliac screw fixation in the same sacral segment. The stability of one lengthened sacroiliac screw fixation in S1 and S2 segments respectively is superior to that of one sacroiliac screw fixation in S1 and S2 segments respectively. The stability of one lengthened sacroiliac screw fixation in S1 and S2 segments respectively is superior to that of one lengthened sacroiliac screw fixation in S1 or S2 segment. The stability of one sacroiliac screw fixation in S1 and S2 segments respectively is markedly superior to that of one sacroiliac screw fixation in S1 or S2 segment. The vertical and rotational stability of lengthened sacroiliac screw fixation and sacroiliac screw fixation in S2 is superior to that of S1.

CONCLUSION

In a finite element model of type C pelvic ring disruption, S1 and S2 lengthened sacroiliac screws should be utilized for the fixation as regularly as possible and the most stable fixation is the combination of the lengthened sacroiliac screws of S1 and S2 segments. Even if lengthened sacroiliac screws cannot be systematically used due to specific conditions, one sacroiliac screw fixation in S1 and S2 segments respectively is recommended. No matter which kind of sacroiliac screw is used, if only one screw can be implanted, the fixation in S2 segment is more recommended than that in S1.

LEVEL OF EVIDENCE

Experimental study Level III.

Treatment of posterior pelvic ring disruptions using a minimally invasive adjustable plate

OBJECTIVE

Iliosacral (IS) screw fixation and posterior tension band plate (TBP) technique are two treatment alternatives for posterior pelvic ring injuries. However, IS screw fixation requires continuous fluoroscopic guidance for appropriate screw insertion and carries a risk of neurovascular injuries. TBP technique also has some disadvantages, including limited reduction potential, difficulty in precontouring the plate and a higher rate of symptomatic implants. To address these limitations, we introduced a minimally invasive adjustable plate (MIAP). This study aims to present the preliminary radiological and clinical results of posterior pelvic ring disruptions treated with MIAP.

METHODS

The MIAP conforms to the irregular shape of posterior pelvic ring and can be used without prebending. This plate has a role in reducing compressed or separated fractures/dislocations. Sixteen patients, including seven males and nine females, were treated with MIAP through a minimally invasive approach. The fracture patterns consisted of six Type B and ten Type C fractures according to OTA classification of fracture. Preoperative and postoperative radiography was taken to assess the fracture displacement and reduction quality. Postoperative rehabilitation programme was individualised and early exercise was encouraged. Patients were followed up and the functional outcome was evaluated based upon the scoring system proposed by Lindahl and associates.

RESULTS

All posterior pelvic ring disruptions were reduced and fixed with MIAP. The average duration of surgery was 49 min, the average radiation exposure was 6s, and the average blood loss was 80 mL for the treatment of posterior pelvic ring injuries. Overall radiological results of the reduction were excellent in eleven patients and good in five. The patients were followed up for 30 months on average. All fractures healed. The functional outcome was excellent in ten patients, good in four and fair in two. There were no iatrogenic neurovascular injuries, implant failures, irritative symptoms or pressure sores due to subcutaneous implantation.

CONCLUSION

Favourable clinical and radiological outcomes can be achieved in treating posterior pelvic disruptions with MIAP. This plate is effective in view of its simplicity, less radiation exposure, safety, minimal invasion and stable fixation.

An evaluation of three-dimensional image-guided technologies in percutaneous pelvic and acetabular lag screw placement

BACKGROUND

Percutaneous stabilization using three-dimensional (3D) navigation system is a promising treatment for pelvic and acetabular fractures. However, there are still some controversies regarding the use of 3D navigation to treat pelvic and acetabular fractures. The purpose of this study was to compare the Iso-C(3D) fluoroscopic navigation, standard fluoroscopy, and two-dimensional (2D) fluoroscopic navigation in placing percutaneous lag screws in pelvic specimens to better understand the merits of 3D navigation techniques.

METHODS

Fifty-four instrumentation procedures were performed in this study using six cadaveric pelvic specimens. Three groups were designated for different procedures and tests: group I, standard fluoroscopy; group II, 2D fluoroscopic navigation; and group III, Iso-C(3D) fluoroscopic navigation. Nine screws were placed in each pelvis, including four screws placed bilaterally through the ilium into S1 and S2 vertebrae, four screws placed bilaterally through anterior and posterior columns of acetabulum, and one screw placed through the pubic symphysis. 3D fluoroscopic techniques were evaluated to determine the accuracy of screw position, instrumentation time, and fluoroscopic time. The data were statistically analyzed using SPSS 13.0.

RESULTS

The malposition rate was 38.89%, 22.22%, and 0% in standard fluoroscopy, 2D fluoroscopic navigation, and Iso-C(3D) fluoroscopic navigation groups, respectively. There was no significant difference between standard fluoroscopy and 2D fluoroscopic navigation. Compared with Iso-C(3D) fluoroscopic navigation, there were significant differences (analysis of variance [ANOVA], P < 0.05). The mean instrumentation operating time using Iso-C(3D) fluoroscopic navigation technique was 15.4 ± 4.5 min. There were significant differences compared with standard fluoroscopy (31.5 ± 6.2 min) and 2D fluoroscopic navigation (26.3 ± 7.5 min; ANOVA, post hoc Scheffe, P < 0.01). The mean fluoroscopic time of Iso-C(3D) fluoroscopic navigation was 66 ± 4.8 min. Compared with standard fluoroscopy (132.8 ± 7.3 min) and 2D fluoroscopic navigation (47.7 ± 5.6 min), there were significant differences (ANOVA, post hoc least significant difference, P < 0.01).

CONCLUSIONS

In the present study, we compared Iso-C(3D) fluoroscopic navigation, 2D fluoroscopic navigation, and standard fluoroscopy. Iso-C(3D) fluoroscopic navigation showed a higher accuracy rate in positioning and a shorter instrumentation operating time. The fluoroscopic time was longer in Iso-C(3D) fluoroscopic navigation than that in standard fluoroscopy, indicating that radiation exposure can be moderately reduced in Iso-C(3D) fluoroscopic navigation operation, although the fluoroscopic time was the shortest in 2D fluoroscopic navigation.

The effect of early operative stabilization on late displacement of zone I and II sacral fractures

INTRODUCTION

This study was designed to evaluate the effect on displacement of early operative stabilization on unstable fractures when compared to stable fractures of the sacrum.

METHODS

Patient consisted of those sustaining traumatic pelvic fractures that also included sacral fractures of Denis type I and type II classification, who were over 18 at the time of the study. Patients were managed emergently, as judged appropriate at the time and then subsequently divided into two cohorts, comprising those who were either treated operatively or non-operatively. The operative group comprised those treated with either internal fixation or external fixation.

RESULTS

Twenty-eight patients had zone II fractures, and 20 had zone I fractures. Zone II fractures showed average displacements of 6.5mm and 6.9mm in the rostral-caudal and anteroposterior directions, respectively, at final follow up. Zone I fractures had average displacements of 6.6mm and 6.1mm in both directions. There were no significant differences between zone I and II sacral fractures (rostral-caudal P=0.74, anteroposterior P=0.24). Average changes in fracture displacement in patients with zone I fractures were 0.6-1.0mm in both directions. Average changes in zone II fractures were 1.8-1.5mm in both directions. There were no significant differences between the average changes in zone I and II fractures in any direction (rostral-caudal P=0.64, anteroposterior P=0.68) or in average displacements at final follow up in any of zone or the entire cohort. Statistically significant differences were noted in average changes in displacement in zone II fractures in the anteroposterior plane (P=0.03) and the overall cohort in the anteroposterior plane (P=0.02).

CONCLUSION

Operative fixation for unstable sacral fractures ensures displacement at follow up is comparable with stable fractures treated non operatively.

Nonoperative immediate weightbearing of minimally displaced lateral compression sacral fractures does not result in displacement

OBJECTIVES

The purpose of this study was to compare the initial and follow-up radiographs of patients with minimally displaced lateral compression (LC) sacral fractures treated nonoperatively with immediate weightbearing to determine the amount of displacement that occurs during healing.

DESIGN

Retrospective review.

SETTING

Single academic urban Level I Trauma Center.

PATIENTS/PARTICIPANTS

We evaluated 118 patients with a LC sacral fracture with <10 mm of displacement. There were 70 women and 48 men whose average age was 46 years and injury severity score was 15 ± 11.

INTERVENTION

Nonoperative treatment consisted of immediate foot-flat mobilization and advancement of weightbearing as tolerated. Repeat radiographs were routinely obtained once the patient had ambulated 50 feet or at 1 week to look for further displacement. Patients were followed with AP radiographs in the clinic at the 4- to 6-week and 10- to 12-week periods, and then every 6-8 weeks until they were healed.

MAIN OUTCOME MEASURES

Specific measurements were made on the initial and follow-up radiographs by 2 observers not involved in the treatment of the patients. A vertical plumb line drawn through the center of the S1 and S2 bodies served as an anchoring point for measurements. Key landmarks were measured on each side of the pelvis, which allowed for determination of the initial and final displacements.

RESULTS

All patients presenting to our center with LC sacral fractures with <10 mm of displacement were treated nonoperatively. One patient failed nonoperative management, demonstrating 5 mm of additional sacral displacement and having substantial pain with attempts to mobilize. This patient was treated with closed reduction and percutaneous pinning of the sacrum and an anterior external fixator. The other 117 patients (99%) healed with minimal additional displacement.

CONCLUSIONS

: Immediate weightbearing, tempered by patient comfort, is a safe and acceptable treatment for minimally displaced LC sacral fractures and results in union with minimal additional displacement.

Methodology and interpretation of radiographic outcomes in surgically treated pelvic fractures: a systematic review

OBJECTIVE

To identify and evaluate previously described methods for the measurement, and interpretation, of radiographic outcomes of operatively treated pelvic fractures.

DATA SOURCES

A systematic review of the available literature was performed using all major databases (MEDLINE, EMBASE, MEDLINE IN-PROGRESS, and Cochrane Central) in August 2009.

STUDY SELECTION

Inclusion criteria were case series, cohort studies, or clinical trials regarding orthopaedic treatment of acute traumatic pelvic ring fractures treated surgically in adults, with at least 12 weeks of radiographic follow-up. Exclusion criteria were case reports or case series of <10 patients, review articles, foreign language articles, and series where time frame of outcome measurement was not stated were excluded.

DATA EXTRACTION

Modality, and timeline, of the radiographic assessment was recorded. Next, the description of the method of radiographic measurement technique used was scrutinized for standardization. The interpretation of the radiographic measurement was evaluated, and any grading scale used was recorded. The interpretation of the quality of the radiographic result as described by each author was recorded. Finally, a qualitative methodological analysis was performed.

DATA SYNTHESIS

Number of standardized radiographic assessment techniques used (3 of 31) and interpretation scales used (13 of 31) were calculated. Nonweighted mean follow-up time (30.6 months) and overall positive radiographic outcomes were calculated (78.6% good or excellent).

CONCLUSIONS

Reporting of radiographic outcomes in pelvic fractures has been done using largely unstandardized and universally untested measurement techniques. The interpretations of these measurements are also inconsistent and untested. Substantive future research is needed in this area.

Can lumbopelvic fixation salvage unstable complex sacral fractures?

BACKGROUND

Traditional screw or plate fixation options can be used to fix the majority of sacral fractures. However, these techniques are unreliable with dysmorphic upper sacral segments, U-fractures, osseous compression of neural elements, and previously failed fixation. Lumbopelvic fixation can potentially address these injuries but is a technically demanding procedure requiring spinal and pelvic fixation and it is unclear whether it reliably corrects the deformity and restores function.

QUESTIONS/PURPOSES

We therefore assessed reduction quality and loss of fixation, pain related to prominent hardware, subjective dysfunction measured by the Short Musculoskeletal Function Assessment (SMFA), and complications.

METHODS

We retrospectively reviewed 15 patients with unstable sacral fractures treated with lumbopelvic fixation between 2002 and 2010. Patients had radiographic monitoring regarding reduction quality and loss of fixation and clinical followup using the SMFA. The minimum followup was 12 months (mean, 23 months; range, 12-41 months).

RESULTS

Posterior reduction quality was 11 of 15 with less than 5 mm persistent displacement and four of 15 with 5 to 10 mm displacement. Loss of fixation was observed in one patient as a result of a technical error. Prominent hardware resulted in greater pain. Despite daily activity and bother subscores improving over time, we found long-term dysfunction in the SMFA. Eleven of the 15 patients were able to return to previous work or activities.

CONCLUSION

Complex posterior pelvic ring injuries of the sacrum not amenable to traditional fixation options can be salvaged with adherence to the technical details of lumbopelvic fixation. Hardware prominence and pain are markedly reduced with screw head recession. Long-term impairment is noted in patients with complex pelvic ring injuries requiring lumbopelvic fixation compared with normative data.

LEVEL OF EVIDENCE

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

Persistent impairment after surgically treated lateral compression pelvic injury

BACKGROUND

Recently, fixation of lateral compression (LC) pelvic fractures has been advocated to improve patient comfort and to allow earlier mobilization without loss of reduction, thus minimizing adverse systemic effects. However, the degree of acceptable deformity and persistence of disability are unclear.

QUESTIONS/PURPOSES

We determined if (1) injury pattern; (2) demographics; (3) final posterior displacement; (4) L5/S1 involvement; (5) associated injuries; and (6) time influence outcome measurements, sexual dysfunction, and pain.

METHODS

We retrospectively reviewed 119 patients with unstable LC injuries treated surgically between 2000 and 2010. There were 52 males and 67 females; mean age was 39 years with a mean body mass index of 27 kg/m(2). All patients underwent clinical examination and radiographic imaging for instability and accompanying injuries. We obtained Short Musculoskeletal Function Assessment (SMFA). The minimum followup was 12 months (mean, 33 months; range, 12-100 months).

RESULTS

SMFA subscores were not affected by injury pattern and demographics. Posterior reduction was less than 5 mm with persistent displacement in 99 of 119 (83%). Displacement of 5 to 10 mm did not affect any SMFA subscore at any time interval. Patients with additional lower extremity injuries had worse SMFA scores. Function improved with time. A visual analog scale pain score of 4 or more at 6 months predicted pain and overall SMFA score at last followup.

CONCLUSIONS

Unstable LC pelvic ring injuries result in persistent disability based on validated outcome measurements. Near anatomical reduction can be achieved and maintained. While our findings need to be confirmed in studies with high rates of followup, patients with unstable LC pelvic injuries should be counseled concerning the possibility of some degree of persistent disability.

LEVEL OF EVIDENCE

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

Multi-disciplinary update on pelvic fracture associated bladder and urethral injuries

Pelvic ring fractures often result in severely injured patients with multiple organ injuries. The most common associated injuries are intraabdominal or urogenital, and urogenital injuries are the most common associated injuries in those with severe pelvic fractures. Prompt and effective diagnosis and management of these injuries is essential to successful outcomes, but this is potentially complicated by poor communication and coordination among the many specialists involved. To address this, we present a multi-disciplinary review of pelvic fracture-associated bladder and urethral injuries that is specifically geared towards orthopaedic, urology, and trauma surgeons caring for these patients.

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.

Biomechanical study of 4-hole pubic symphyseal plating: locked versus unlocked constructs

To the authors' knowledge, no published studies have examined the use of locking plates on injuries of the anterior pelvic ring. The purpose of this study was to determine whether locked plates provide enhanced stability in the treatment of pubic symphyseal disruptions. Completely unstable pelvic injuries were simulated in pelvic Sawbones (model 1301; Pacific Research Laboratories, Vashon, Washington) and 2 different fixation constructs used for anterior fixation (4-hole, 3.5-mm pubic symphysis plate with all locked or all unlocked screws). Adjunctive sacroiliac screw fixation with a single 7.3-mm screw placed into S1 was used in all specimens. Specimens were analyzed for motion at the pubic symphysis and sacroiliac joints using a Material Testing System (MTS Systems Corporation, Eden Prairie, Minnesota). Each specimen was subjected to compressive loading in a single-limb stance. Side loading was also examined. The main outcome measurement was motion at the pubic symphysis and sacroiliac joints and overall construct stiffness. No significant difference existed in overall construct stiffness between the 2 methods of pubic symphysis fixation. The motions at the pubic symphysis or injured sacroiliac joints were not significantly different. In addition, motion at the pubic symphysis joint with lateral load was not improved with a locking construct.No significant difference existed between 4-hole locked or unlocked constructs used for fixation of the pubic symphysis. No apparent advantage of locking screws exists for disruptions of the pubic symphysis, and recent reports have questioned the possibility of catastrophic failure.

Comparison of stability of two kinds of sacro-iliac screws in the fixation of bilateral sacral fractures in a finite element model

OBJECTIVE

To compare the stability of lengthened sacro-iliac screw and sacro-iliac screw for the treatment of bilateral vertical sacral fractures to provide reference for clinical application.

METHODS

A finite element model of Tile C pelvic ring injury (bilateral type Denis II fracture of sacrum) was produced. (Tile and Denis are surgeons, who put forward the classifications of pelvic ring injury and sacral fracture respectively.) The bilateral sacral fractures were fixed with a lengthened sacro-iliac screw and a sacro-iliac screw in seven types of models, respectively. The translation and angular displacement of the superior surface of the sacrum in the case of standing on both feet were measured and compared.

RESULTS

The stability of one lengthened sacro-iliac screw fixation in the S1 or S2 segment is superior to that of two bidirectional sacro-iliac screws in the same sacral segment; the stability of one lengthened sacro-iliac screw fixation in S1 and S2 segments, respectively, is superior to that of two bidirectional sacro-iliac screw fixation in S1 and S2 segments, respectively; the stability of one lengthened sacro-iliac screw fixation in S1 and S2 segments, respectively, is superior to that of one lengthened sacro-iliac screw fixation in the S1 or S2 segment; the stability of two bidirectional sacro-iliac screw fixation in S1 and S2 segments, respectively, is markedly superior to that of two bidirectional sacro-iliac screw fixation in the S1 or S2 segment and is also markedly superior to that of one sacro-iliac screw fixation in the S1 segment and one sacro-iliac screw fixation in the S2 segment; the vertical stability of the lengthened sacro-iliac screw or the sacro-iliac screw fixation in S2 is superior to that of S1. The rotational stability of the lengthened sacro-iliac screw or sacro-iliac screw fixation in S1 is superior to that of S2.

CONCLUSION

S1 and S2 lengthened sacro-iliac screws should be used for the fixation in bilateral sacral fractures of Tile C pelvic ring injury as far as possible and the most stable fixation is the combination of the lengthened sacro-iliac screws of S1 and S2 segments. Even if lengthened sacro-iliac screws cannot be used due to limited conditions, two bidirectional sacro-iliac screw fixation in S1 and S2 segments, respectively, is recommended. No matter which kind of sacro-iliac screw is applied, the fixation combination of S1 and S2 segments is strongly recommended to maximise the stability of the pelvic posterior ring.

Management of lumbosacropelvic fracture-dislocation using lumbo-iliac internal fixation

OBJECTIVE

Traumatic lumbosacropelvic fracture-dislocation is a rare but potentially serious injury. Conventional methods like lumbosacral fixation used to treat such injuries often result in suboptimal outcome secondary to complications like pseudoarthroses, sagittal imbalance and hardware failure. In this study, we retrospectively analysed the clinical features and management for this trauma using lumbo-iliac fixation.

METHODS

Eight patients (6 male, 2 female; 21-52 years old, mean: 38.4) with traumatic lumbosacropelvic fracture-dislocation were surgically managed by lumbo-iliac internal fixation after lumbosacral decompression. Patients were followed up for 24-40 months (mean: 31.6). American Spine Injury Association (ASIA) scores were measured before surgery and at the last follow-up, and statistically analysed.

RESULTS

After surgery, all patients experienced improved sensory and motor performance. Six patients showed recovery of bowel and bladder functions. Immediately after lumbo-iliac fixation, all patients could turn in bed without assistance. Lumbosacral alignment was restored immediately after surgery and no dislocation was observed during follow-up. Radiography indicated excellent integration between the autograft and the vertebrae. After surgery, no patient experienced neurological deterioration.

CONCLUSION

Our experience with these cases suggests that early surgical decompression and posterior lumbo-iliac internal fixation can effectively restore spinal alignment, stabilise the spine, and improve neurological symptoms for this complex trauma.

Surgical management of U-shaped sacral fractures: a systematic review of current treatment strategies

PURPOSE

U-shaped sacral fractures usually result from axial loading of the spine with simultaneous sacral pivoting due to a horizontal fracture which leads to a highly unstable spino-pelvic dissociation. Due to the rarity of these fractures, there is lack of an agreed treatment strategy.

METHODS

A thorough literature search was carried out to identify current treatment concepts. The studies were analysed for mechanism of injury, diagnostic imaging, associated injuries, type of surgery, follow-up times, complications, neurological, clinical and radiological outcome.

RESULTS

Sixty-three cases were found in 12 articles. No Class I, II or III evidence was found in the literature. The most common mechanism of injury was a fall or jump from height. Pre-operative neurological deficit was noted in 50 (94.3%) out of 53 cases (not available in 10 patients). The most used surgical options were spino-pelvic fixation with or without decompression and ilio-sacral screws. Post-operative complications occurred in 24 (38.1%) patients. Average follow-up time was 18.6 months (range 2-34 months). Full neurological recovery was noted in 20 cases, partial recovery in 14 and 9 patients had no neurological recovery (5 patients were lost in follow-up). Fracture healing was mentioned in 7 articles with only 1 case of fracture reduction loss.

CONCLUSION

From the current available data, an evidence based treatment strategy regarding outcome, neurological recovery or fracture healing could not be identified. Limited access and minimal-invasive surgery focussing on sacral reduction and restoration seems to offer comparable results to large spino-pelvic constructs with fewer complications and should be considered as the method of choice. If the fracture is highly unstable and displaced, spino-pelvic fixation might offer better stability.

Percutaneous limited internal fixation combined with external fixation to treat open pelvic fractures concomitant with perineal lacerations

External fixation combined with colostomy is a traditional management of the pelvic fractures associated with perineal lacerations. However, malunion and dysfunction caused by malreduction and loss of reduction are common. One-stage definitive fixation without soft tissue harassment is requisite for the treatment. The purpose of this study was to assess the outcome of 1-stage definitive fixation by combining percutaneous limited internal fixation and external fixation in the treatment of pelvic fractures with perineal lacerations. Eighteen adults with high-energy unstable pelvic ring fractures associated with perineal lacerations were admitted between June 2003 and December 2010. Mean follow-up was 28 months. After wound closure and colostomy, 10 patients received external fixation and percutaneous screw fixation, and 8 patients underwent external fixation. Demographics, wound and fracture classification, and Injury Severity Score were comparable between the groups (P>.05). Initial reduction quality was comparable between the groups (P=.14), but the loss of reduction during follow-up was more significant in the external fixation group (P=.004). Combined fixation achieved better functional results than external fixation (P=.02). There were 2 cases of superficial wound infection in each group (P=1.0). By combining debridement, wound closure, colostomy, percutaneous limited internal fixation, and external fixation, we improved pelvic fracture recovery while reducing the risk of infection. One-stage definitive fixation is a better choice than external fixation in the treatment of open pelvic fracture concomitant with perineal wound.

A minimally invasive stabilizing system for dorsal pelvic ring injuries

BACKGROUND

Open reduction and stabilization of dorsal pelvic ring injuries is accompanied by a high rate of soft tissue complications. Minimally invasive techniques have the potential to decrease soft tissue trauma, but the risk of iatrogenic nerve and vessel damage through the reduced surgical exposure should be considered. We treated these injuries using a transiliac internal fixator (TIFI) in a minimally invasive technique characterized by implantation of a pedicle screw and rod system, bridging the sacroiliac joints and the sacral area.

QUESTIONS/PURPOSES

We asked whether (1) we could achieve anatomic restoration with the device, (2) specific complications were associated with this minimally invasive approach (particularly enhanced intraoperative blood loss, soft tissue complications, and iatrogenic neurovascular damage), and (3) function 3 years after trauma was comparable to that of established methods.

METHODS

We retrospectively reviewed 67 patients with dorsal pelvic injuries during a 7-year period. We evaluated the (1) reduction by grading the maximal displacement measured with three radiographic views, (2) the complications during the observation period, and (3) the function with a validated questionnaire (Pelvic Outcome Score) in all but five patients at least 3 years after trauma (mean, 37 months; range, 36-42 months).

RESULTS

At last followup we observed a secondary fracture displacement greater than 5 mm in one patient. The intraoperative blood loss was less than 50 mL in all patients. No neurovascular lesions occurred owing to implantation. Four patients had wound infections, one had loosening of a single pedicle screw, and one had an iatrogenic screw malpositioning. Thirty-five of the 62 patients achieved Pelvic Outcome Scores of either a maximum score or 6 of 7 points.

CONCLUSION

Our observations suggest TIFI is a reasonable alternative to other established fixation devices for injuries of the dorsal pelvic ring with minor risks of major blood loss or iatrogenic neurovascular damage.

LEVEL OF EVIDENCE

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

Evaluation of 2D and 3D navigation for iliosacral screw fixation

PURPOSE

Image guidance is essential in some orthopedic surgical procedures, especially iliosacral screw fixation. Currently, there is no consensus regarding the best image guidance technique. An ex-vivo study was performed to compare conventional, 2-dimensional (2D), and 3D imaging techniques and determine the optimal image guidance technique for pelvic surgery.

METHODS

Plastic (n = 9) and donated cadaver pelvises (n = 8) were evaluated in the laboratory. The pelvises were positioned on radiolucent operation tables in a prone position. Transiliosacral screws were inserted without or with 2D- and 3D-navigational support. A digital mobile X-ray unit with flat-panel fluoroscopy and navigation software was used to measure precision, radiation exposure, and time requirements.

RESULTS

2D-navigation resulted in 40% incorrect screw positioning for the cadavers, 6% for the plastic phantoms, and 21% overall. The highest accuracy was accomplished with 3D-navigation (plastic: 100%; cadavers: 83%; p < 0.05). The dose-area product showed that both 2D- and 3D-navigation required increased exposure compared to the conventional technique (p < 0.01). For both plastic and cadaver specimens, navigated techniques required significantly longer times for screw insertion than the conventional technique (p < 0.01).

CONCLUSION

3D image guidance for transiliosacral screw fixation enabled more accurate screw placement in S1 and S2 vertebrae. However, radiation exposure in 3D-navigation was excessive; thus, we recommend avoiding 3D-navigation in young patients. A primary advantage of 3D-navigation was that the operating team could leave the room during the scan; thus, it reduced their radiation exposure. Moreover, the time required for screw insertion with 3D-navigation was similar to that required in the conventional technique; thus, 3D-navigation is recommended for older patients.

Transiliac-transsacral screws for posterior pelvic stabilization

Typical posterior pelvic fixation constructs use one or more large screws inserted from the lateral iliac cortex into the safe upper sacral ala or body. As a result of the deforming forces acting perpendicular to the implant axis, routine iliosacral screw fixation may not provide adequate stabilization, especially in certain unstable injuries. Longer iliosacral screws that traverse the entire upper sacrum and exit the contralateral iliac cortex may improve holding power and also stabilize concomitant contralateral posterior pelvic injuries. These transiliac-transsacral screws are reliably safe to insert using routine intraoperative fluoroscopy, and they provide durable fixation. These screws require careful preoperative planning and more precise technical attention during insertion because they pass through both sacral alar zones. Transiliac-transsacral screws may be particularly useful in the presence of osteoporosis, significant posterior pelvic instability including spinopelvic dissociation, patient obesity, anticipated noncompliant behavior, bilateral posterior pelvic injuries, and nonunion procedures.

Nonunion of a sacral fracture refractory to bone grafting: internal fixation and osteogenic protein-1 (BMP-7) application

Nonunion of a sacral fracture is a serious clinical condition: chronic pain, sitting discomfort, limp, neurological implications, and inability to work are frequent findings. Surgical treatment of these injuries often turns out to be technically difficult also for the expert pelvic surgeon and not infrequently provides poor radiographic and clinical results. The gold standard treatment at present is open excision, reaming of the nonunion site and internal fixation, performed by a multi-stage approach; as an adjunct, autologous cancellous bone grafting is usually performed in most severe cases. We report a case of a sacral nonunion in which traditional techniques failed, successfully treated by osteogenic protein-1 (BMP-7) application. The employment of BMPs demonstrated successful results in various types of fracture, but there is limited experience about their use in pelvic ring injuries: Further studies are necessary to better know the possible complications and to define their actual potential.

Prevalence of sacral dysmorphia in a prospective trauma population: Implications for a "safe" surgical corridor for sacro-iliac screw placement

Background

Percutaneous sacro-iliac (SI) screw fixation represents a widely used technique in the management of unstable posterior pelvic ring injuries and sacral fractures. The misplacement of SI-screws under fluoroscopic guidance represents a critical complication for these patients. This study was designed to determine the prevalence of sacral dysmorphia and the radiographic anatomy of surgical S1 and S2 corridors in a representative trauma population.

Methods

Prospective observational cohort study on a consecutive series of 344 skeletally mature trauma patients of both genders enrolled between January 1, 2007, to September 30, 2007, at a single academic level 1 trauma center. Inclusion criteria included a pelvic CT scan as part of the initial diagnostic trauma work-up. The prevalence of sacral dysmorphia was determined by plain radiographic pelvic films and CT scan analysis. The anatomy of sacral corridors was analyzed on 3 mm reconstruction sections derived from multislice CT scan, in the axial, coronal, and sagittal plane. "Safe" potential surgical corridors at S1 and S2 were calculated based on these measurements.

Results

Radiographic evidence of sacral dysmorphia was detected in 49 patients (14.5%). The prevalence of sacral dysmorphia was not significantly different between male and female patients (12.2% vs. 19.2%; P = 0.069). In contrast, significant gender-related differences were detected with regard to radiographic analysis of surgical corridors for SI-screw placement, with female trauma patients (n = 99) having significantly narrower corridors at S1 and S2 in all evaluated planes (axial, coronal, sagittal), compared to male counterparts (n = 245; P < 0.01). In addition, the mean S2 body height was higher in dysmorphic compared to normal sacra, albeit without statistical significance (P = 0.06), implying S2 as a safe surgical corridor of choice in patients with sacral dysmorphia.

Conclusions

These findings emphasize a high prevalence of sacral dysmorphia in a representative trauma population and imply a higher risk of SI-screw misplacement in female patients. Preoperative planning for percutaneous SI-screw fixation for unstable pelvic and sacral fractures must include a detailed CT scan analysis to determine the safety of surgical corridors.

Minimally invasive reduction of vertically displaced sacral fracture without use of traction table

Background

Treatment of vertically displaced sacral fracture can be difficult even for the expert traumatologist. Traditional reduction methods can show some limitations; we suggest a minimally invasive technique, which could be effective, tissue sparing and economic in terms of equipment needed.

Materials and methods

Our retrospective study included 11 patients with average age of 40.2 years (range 24–59 years), with type C pelvic ring disruption with monolateral sacral fracture (C1.3), who underwent surgical treatment from April 2007 to March 2008 using the minimally invasive technique. Radiographic examination, using Matta’s criteria, was carried out pre-operatively, post-operatively and at least at 1 year after surgery. All patients were functionally evaluated using Majeed’s grading scale with mean follow-up time of 18.9 months (range 14–25 months).

Results

Pre-operative displacements averaged 10.8 mm (range 7–21 mm); post-operative displacements averaged 5.4 mm (range 3–12 mm), with excellent or good reduction in 91% of cases. No major complications occurred. On functional evaluation, 82% of patients obtained good or excellent results.

Conclusion

The minimally invasive reduction technique, requiring a limited surgical approach and a standard radiolucent table, is in our experience a satisfactory procedure for management of monolateral vertically displaced sacral fracture.

Biomechanical aspects of pelvic ring reconstruction techniques: Evidence today

Despite the remarkable advances achieved within the boundaries of the new discipline of Pelvic surgery, pelvic ring disruptions remain challenging and complex problems in orthopaedics. The long-term complications related to reconstruction techniques of these injuries have motivated researchers and surgeons to explore various alternative treatment modalities. Several biomechanical studies have addressed these issues. We performed a medline search including studies published during the last 30 years. Our search yielded 114 studies, 39 of which met the pre-specified inclusion criteria and were further critically analysed and discussed regarding the biomechanical aspects of pelvic ring reconstruction techniques. Based on observational approach and evaluation of the studies specific keypoints are highlighted comprising the clinical translation of the biomechanical supported findings.

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.

Locked transsacral screw fixation of bilateral injuries of the posterior pelvic ring: initial clinical series

OBJECTIVES

The purpose of this study was to evaluate the clinical safety and efficacy of using a cannulated transsacral screw having a novel locking capability for pelvic fracture fixation.

DESIGN

Retrospective analysis of a treatment protocol, patient series.

SETTING

Level I trauma center.

PATIENTS

Beginning in 2001, 10 patients with bilateral injury to the posterior pelvic ring were treated using a cannulated transsacral screw having a novel locking capability. Patients ranged in age from 21 to 64 years. Follow-up averaged 2 years (range, 1-5 years). Preoperative and postoperative radiographic evaluation included anteroposterior, inlet and outlet pelvic x-rays, and two-dimensional computerized tomography with 3-mm slice thickness. Candidates for this fixation required adequate space estimated on computerized tomography across either the first or second sacral body.

INTERVENTION

Locked transsacral screw fixation of bilateral injuries of the posterior pelvic ring consisting of a long 7.0-mm cannulated screw inserted over a washer from the near ilium, across one sacroiliac joint, through the body of the sacrum, and across the other sacroiliac joint, exiting the far iliac cortex. A self-locking nut was placed on the distal end of the screw.

MAIN OUTCOME MEASUREMENTS

Intraoperative iatrogenic nerve root injuries, postoperative screw position, and maintenance of the fixation construct until fracture healing.

RESULTS

There were no iatrogenic nerve injuries. Satisfactory screw position was documented on the postoperative computerized tomography in all cases. Fixation failure did not occur and satisfactory pelvic ring position was maintained in all cases.

CONCLUSIONS

Locked transsacral screw fixation is a safe and effective technique that should be added to our surgical armamentarium. Indications include bilateral posterior injury as well as any situation in which routine transsacral screw fixation might otherwise be considered such as the presence of pelvic osteopenia or insufficient space for a second point of posterior fixation.

Low-energy osteoporotic pelvic fractures

The vast majority of pelvic fractures in geriatric patients are classified as stable injuries. The current treatment strategies of these fractures involve pain management and mobilization. Pain-related immobility may pose a serious hazard to patients with severe preexisting comorbidities. There is paucity of literature on the outcome and mortality after osteoporotic pelvic fractures in the elderly. This review aims to provide an overview of epidemiology, injury mechanism, fracture patterns, management and outcome after osteoporotic pelvic fractures.

Locked plates reduce displacement of vertically unstable pelvic fractures in a Mechanical Testing Model

BACKGROUND

The purpose of this study is to compare a locked screw construct to a single iliosacral screw for fixation of a vertically unstable pelvic ring injury in a transforaminal sacral fracture model.

METHODS

Orthopaedic Trauma Association type 61-C1.3a2c5 fractures were created in 10 fresh frozen cadaveric pelvis specimens. Specimens were divided into two groups of five. In both groups, the anterior ring was stabilized with a six-hole 3.5-mm reconstruction plate. In the locked plate (LP) group, the posterior injury was stabilized using a two-hole locking plate with one solid 5.0-mm locking iliosacral screw directed onto the S1 body and a second locking screw directed into the lateral sacral ala. In the iliosacral screw group, the posterior injury was stabilized using a single cannulated 7.3-mm screw. Testing was conducted on a Materials Testing System. Values for displacement and rotation were recorded. Each pelvis was axially loaded with a compressive sine wave from 175 N to 350 N for 10,000 cycles to simulate limited weight bearing, with data recorded at 1,000 cycle increments.

RESULTS

Two specimens in the iliosacral screw group displaced more than 1 cm during the first 1,000 cycles. These two specimens displayed gross fracture motion in all planes. All five specimens in the LP group completed 10,000 cycles of testing with less than 1 cm of displacement. A vector displacement calculation from the plane displacement data revealed that the LP group had significantly less displacement (median 1.9 mm) than the specimens in the iliosacral group (median 6.7 mm; p = 0.008) after 10,000 cycles.

CONCLUSIONS

A two-hole plate locked head screw construct resulted in less displacement than a single iliosacral screw in a transforaminal sacral fracture model.

Combined injuries of the pelvis and acetabulum: nature of a devastating dyad

OBJECTIVES

To describe the clinical characteristics of combined injuries of the pelvis and acetabulum, which have not been previously described. We hypothesize that this combination of injuries affects not only the postinjury hemodynamics of the patient, but the outcome of subsequent acetabular fracture treatment.

DESIGN

Retrospective study.

SETTING

Level I trauma center.

METHODS

The data collected included patient demographics, fracture classification, Injury Severity Score, systolic blood pressure on arrival, amount of packed red blood cells transfused, time to operation, perioperative complications, and radiographic outcomes. Age- and sex-matched control groups of patients with pure pelvic fractures and pure acetabular fractures were compared with the combined injury group to assess injury severity characteristics. To determine the independent factors influencing the postoperative residual displacement of the acetabulum, multiple linear regression analysis was used.

RESULTS

Between January 1, 1998, and December 31, 2007, there were 1612 patients with either pelvic or acetabular fractures requiring admission to our institution, of which 82 (5.1%) had the combination of an unstable pelvic injury (Orthopaedic Trauma Association [OTA] 61 Types B/C) and a displaced acetabular fracture (OTA 62). Eighty-two patients with an isolated unstable pelvic injury and 82 patients with an isolated displaced acetabular fracture were chosen from the same study period to act as control groups. Patients in the combined group were significantly more injured as compared with the displaced acetabular fracture control group with regard to Injury Severity Score (P < 0.001), systolic blood pressure (P < 0.001), and packed red blood cells (P < 0.001). In the combined group, the most common pelvic fracture patterns were OTA 61.B1 and B2. Transverse-type acetabular fractures patterns (OTA 62.B1 and B2) accounted for 61.2% of all acetabular fractures in the combined group. The most frequent injury combination was a transverse-type acetabular fracture with an associated ipsilateral anterior disruption of the sacroiliac joint. Sixty-eight patients underwent surgical intervention at a mean time of 5.7 days. The mean postoperative displacement of acetabular fracture reduction was 2.2 mm as evaluated by radiographs. Multiple regression analysis revealed that the amount of postoperative posterior pelvic displacement, Type B2 acetabular fractures, and patient age were significant predictors of the amount of residual acetabular displacement found postoperatively.

CONCLUSION

Patients with combined pelvic and acetabular fractures represent a serious injury that includes the resuscitative challenges of pelvic injuries coupled with the difficulties of precise reduction of acetabular fractures. To obtain optimal reduction of the acetabulum, initial accurate reduction of the posterior pelvic lesion appears to be necessary.

Health-related quality of life and life satisfaction in patients following surgically treated pelvic ring fractures. A prospective observational study with two years follow-up

BACKGROUND

Pelvic ring fractures caused by high-energy trauma are severe injuries with well described radiological and clinical outcomes, whereas description from the patient's perspective is less well documented. The purpose of this study was to investigate patient-reported outcome following surgical treatment of pelvic fractures using quality of life instruments.

METHODS

All 54 patients (28 male/26 female, ages 16-68) with pelvic fractures referred to our institution for surgical treatment 2003-2005 were prospectively included. The most common trauma was motor vehicle accident (44%). Additional injuries were seen in 74% and in 31% the ISS was >or=16. There were 31 B and 23 C type fractures. Patients were followed for two years using two validated questionnaires, SF-36 and LiSat-11, the latter an instrument consisting of 11 questions for evaluation of satisfaction with different aspects of life.

RESULTS

45 patients could be followed according to the study protocol for two years while 2 were untraceable and 1 died from unrelated causes. Of 6 nonresponders, 5 were unable due to psychiatric disorder. At two years pelvic fracture patients scored lower than the reference population in both physical and mental domains (SF-36). Highest mean score, 68, was in the domain Social Function (norm 89) while lowest mean score, 38, was in the domain Role Physical (norm 86). The mean score closest to the normative was for general health with 61 for patients and 78 for the normative group. In LiSat-11 pelvic fracture patients scored lower than the reference population in all areas. Satisfaction with life as a whole was 31% compared with 60% in the normative group.

CONCLUSIONS

Two years after surgical treatment of pelvic ring fractures, patients reported substantially lower quality of life for both physical and mental domains, when compared with a reference population, even when radiological and clinical outcomes were considered favourable.

Accuracy of minimally invasive navigated acetabular and iliosacral fracture stabilization using a targeting and noninvasive registration device

BACKGROUND

To assess the feasibility and accuracy of guide pin (GP) placement using a combined noninvasive patient immobilization and stereotactic targeting system in computer-assisted percutaneous pelvic fracture stabilization.

METHODS

A total of 12 patients with negligible dislocated unstable pelvic fractures were enrolled in this study, performed between February 2002 and October 2005. Our original plans included 13 GP placements in the iliosacral area (SF) and 8 in the acetabular (AF) area. Patients were bedded on a noninvasive dual-vacuum immobilization device. Interventions were planned on a navigation system using intraoperatively acquired CT data. Radiodense markers glued to the skin and the immobilization device provided synchronization between virtual data set and real anatomical situation. A stereotactic targeting device was used for stabilization of GP tracking. GP positions were verified intraoperatively by CT, followed by fracture stabilization with cannulated screws.

RESULTS

Mean GP placement accuracy according to plan: (1) SF-cohort: 2.8 mm (SD 2.0 mm, range 0.5-9.0 mm) at the bony entry point and 3.8 mm (SD 2.3 mm, range 0.6-9.5 mm) at the target point. (2) AF-cohort: 3.0 mm (SD 0.9 mm, range 1.6-4.9 mm) at the bony entry point and 3.9 mm (SD 1.9 mm, range 1.6-7.5 mm) at the target point. GP placement succeeded optimally in 11 out of 13 cases in the SF-cohort, and 6 out of 8 cases in the AF-cohort. The individual average dose-length product (DLP) per successful finished procedure was 1,576 mGy x cm (SD 812 mGy x cm, range 561-2,739 mGy x cm).

CONCLUSION

Our findings substantiate application of the noninvasive patient immobilization and stereotactic targeting system as effective in computer-assited percutaneous stabilization of sacral bone fractures/SI joint disruptions and coronally oriented acetabular dome fractures. We recommend according to the ALARA (as low as reasonable achievable) principle: first, the kV and mAs values have to be reduced. Second, the scanned volume has to be strictly limited to the area of interest. Third, the number of control CTs have to be minimized. Also, the IsoC might be a better choice for implant tracking below 12 cm to reduce the radiation dose to the minimum. We believe that for all high-precise GP placements in the acetabular column area, further improvements in GP guidance (inhibiting pin tip slipping and detecting intraosseous GP deflection) are necessary.

Computer Assisted Pelvic Surgery: Registration Based on a Modified External Fixator

A fundamental step in Computer Assisted Surgery (CAS) is the registration, when the preoperative virtual data and the corresponding operative anatomy of the region of interest are merged. To provide exact landmarks for anatomical registration, a tubular external fixator was modified. Two intact pelvic bones (one artificial foam pelvis and one cadaver specimen) were used for the experimental setup. Registration was carried out using a standardized protocol for anatomy-based registration in the control group; anatomical registration was achieved using a modified external fixator in the study group. This external fixator had titanium fiducials wedged into the fixator carbon tubes serving as landmarks for paired-point registration. The tubes were used for surface registration. The standard anterior pelvis fixator assembly was augmented with additional bilateral tubes oriented towards the posterior, enabling registration of the sacroiliac areas. The accuracy of registration was checked by "reversed verification", where the examiner used only the screen display to control the virtual position of the pointer tip in relation to selected landmarks. By virtual matching, the real distance was measured with a digital caliper. We defined the verification as "accurate" when the residual distance was less than 1 mm; "acceptable" when it was between 1 mm and 2 mm; and "insufficient" when it exceeded 2 mm. The paired T-test with significance levels of p < 0.05 was used for statistical analysis. The anatomical registration based on the external fixator landmarks was statistically as accurate as that obtained using anatomical landmarks on the pelvic bone. This study concludes that the external fixator, a conventional tool in the management of acute traumatic pelvic instability, can also be useful for landmark registration in CAS.

Pelvic ring fractures internal fixation: iliosacral screws versus sacroiliac hinge fixation

INTRODUCTION

Pelvic ring fractures are severe injuries whose functional results depend on the quality of reduction. Numerous internal fixation alternatives have been described, but the biomechanical studies comparing them remain rare.

HYPOTHESIS

This study compared the biomechanical behavior of iliosacral screws (ISS) with sacroiliac hinge type fixation (SIF) following unstable pelvic ring fractures fixation.

MATERIALS AND METHODS

A lesion simulating sacroiliac disruption and pubic disruption was created on 14 cadaver pelves. After randomization, the fractures were internally fixed using an anterior plate associated with either an ISS or an SIF. The specimens were then submitted to forces applied vertically at the coxofemoral joints. Relative movements in vertical translation and in rotation between the iliac wing and the sacrum, as well as the stiffness and the forces at failure of the assemblies were measured and compared.

RESULTS

The mean age of the bodies was 66 years (+/-8). No significant difference was demonstrated between the groups in terms of residual motion and stiffness in both vertical and rotational displacement. The results showed a slight residual mobility in rotation of the hemipelvis. The SIFs presented greater, although non significant resistance to failure. No fixation, however, restituted stiffness comparable to a healthy pelvis.

DISCUSSION

The results of this study show that a Tile C.1.2-type injury to the pelvic ring can be treated as effectively with ISS or SIF when combined anterior and posterior fixations are performed. SIF therefore seems reliable and its continued use is justified. The long-term clinical outcomes should nevertheless be evaluated, notably on the younger population, more often affected by this type of injury.

U-shaped sacral fractures: surgical treatment and quality of life

BACKGROUND

U-shaped sacral fractures are rare and highly unstable pelvic ring fractures. They are not recognised in the standard classification systems of these fractures. The fracture pattern is associated with significant neurological injury and can lead to progressive deformity and chronic pain if not diagnosed and treated properly. In recent years a variety of surgical strategies have been shown to facilitate early mobilisation and reduce early mortality as compared to non-operative strategies. Poor evidence, however, has hampered the development of a standard treatment algorithm. As for the long-term morbidity, the influence of operative treatment may be difficult to assess due to associated injury. However, evidence exists that there is a significant effect on the long-term morbidity.

OBJECTIVE

To assess the injury characteristics, choice of treatment and quality of life of U-shaped sacral fractures.

METHODS

Eight polytraumatised patients with U-shaped sacral fractures were identified over a 7-year period and evaluated retrospectively. They were analysed for fracture classification, associated injury, and injury severity. Clinical and Radiological results were evaluated. Neurological outcome was retrospectively classified by Gibbons' criteria. Long-term quality of life outcome was evaluated using the EuroQoL-6D questionnaire.

RESULTS

The study population consists of five women and three men; with a median age of 29 years. All patients sustained severe associated injury. The Injury Severity Score ranged from 17 to 45 (median 23). The median time between trauma and definitive internal fixation was 4 days (range, 2-22 days). Definitive fixation included either percutaneous iliosacral screws (n=2), transsacral plate osteosynthesis (n=1) or triangular osteosynthesis with (n=4) or without transsacral plating (n=1). Early postoperative mobilisation and early partial weight-bearing were encouraged when possible. Follow-up ranged from 5 to 65 months (median, 36 months). Pain, mood disorders and mobility problems mainly influenced patients' present general health status.

CONCLUSION

U-shaped sacral fractures present a rare and heterogeneous injury. Operative treatment depended mainly on fracture type, associated spinal fractures, and the surgeon's preference. Long-term quality of life is dominated by pain, mood disorders and moderate mobility problems.

Saddle-horn injury of the pelvis. The injury, its outcomes, and associated male sexual dysfunction

BACKGROUND

A saddle-horn injury of the pelvis occurs when a horse rider is thrown into the air and then falls back, with the perineum coming into contact with the saddle or saddle horn. The purpose of this study was to evaluate the characteristics and clinical outcomes, including sexual dysfunction, of this injury.

METHODS

We conducted a retrospective review of a consecutive series of male patients who had a saddle-horn injury of the pelvis after being bucked from a horse. Clinical and radiographic results were assessed more than eighteen months after the injury. Functional outcome measures were evaluated at the time of the latest follow-up with use of visual analog pain scales, a questionnaire addressing occupational and recreational function, the International Index of Erectile Function instrument, the Iowa pelvic score, and the Short Form-36.

RESULTS

Twenty patients were assessed at an average of thirty-three months after the injury. Seventeen patients had returned to riding horses, and ten felt that they had returned to their previous level of recreation, which had been "heavy" in nine cases and "moderate" in one. Eighteen patients had returned to their previous employment. Eighteen patients were found to have sexual dysfunction at the time of the latest follow-up. The mean Iowa pelvic score was 84 points (range, 56 to 99 points). The Short Form-36 outcomes scores were diminished in two subsections, role physical and role emotional, compared with population norms.

CONCLUSIONS

Mild pain can be expected after saddle-horn injury despite successful surgical treatment, and the injury does not preclude a return to previous employment or riding horses. A high proportion of men experience erectile dysfunction, which is unlikely to respond well to pharmacologic therapy.

Emergent management of APC-2 pelvic ring injuries with an anteriorly placed C-clamp

OBJECTIVE

Can anteriorly placed pelvic C-clamps be used successfully in the emergent management of APC-2 pelvic fractures?

DESIGN

Prospective cohort.

SETTING

Level 1 trauma center.

PATIENTS

A single-surgeon series of 24 patients with an anteroposterior compression type 2 pelvic fracture.

INTERVENTION

Application of an anteriorly placed pelvic C-clamp within 2 hours of presentation.

MAIN OUTCOME MEASUREMENTS

Response to hypotension, complications related to pin placement, application time, and symphyseal reduction measured on anteroposterior radiograph.

RESULTS

Twenty-four patients with a mean age of 29 years (14-58 years) had an APC-2 pelvic fracture diagnosed by an anteroposterior radiograph of the pelvis on presentation. All patients were emergently managed with an anteriorly placed C-clamp applied in the emergency room (10), angiography suite (9), or operating room (5). Eleven patients presented with hypotension (systolic blood pressure <90 mm Hg) and had an average elevation of their blood pressure of 23 mm Hg (10-44 mm Hg). The symphyseal separation was reduced from a mean of 4.5 cm (3-9 cm) to <2 cm in all cases and to <1 cm in 21 of 24 cases. Complications included 1 misdiagnosis of an APC-3 injury and 2 cases in which the clamp became dislodged when the patients were rolled in the intensive care unit. Thirteen patients required laparotomy or angiography for further management after the C-clamp was applied. The C-clamp was easily draped out of the field for both procedures.

CONCLUSIONS

The pelvic C-clamp can be placed anteriorly as a part of the early management of APC-2 pelvic fractures with a short application time in a variety of patient care areas.

Utility of intraoperative three-dimensional imaging at the hip and knee joints with and without navigation

Intraoperative three-dimensional imaging in orthopaedic trauma care has achieved greater importance over the last few years in some specialized hospital centers. For various types of peripheral-extremity trauma, clinical studies have confirmed, on the basis of three-dimensional information, an intraoperative revision rate ranging from 7% to 19%. Three-dimensional C-arm imaging may be used to achieve adequate intraoperative information about the quality of fracture reduction, residual steps, and correct implant placement, and this technique has been described for use in both the hip joint (for acetabular fractures, isolated femoral head [Pipkin-type] fractures, three-dimensional navigated sacroiliac screw or acetabular column screw placements, and, less frequently, for navigated drilling of tumors or osteochondral lesions) and the knee joint (for tibial plateau fractures, complex distal femoral condylar fractures, and navigated targeting of osteochondral lesions in combination with the use of preoperative magnetic resonance imaging scans). Major limitations of this technology include increased intraoperative time requirements, limited image quality compared with that of computed tomographic scans, cost, specific positioning techniques, and the need for radiolucent operating-room tables. Although prospective studies have yet to be conducted, the ways in which the surgeon will benefit from the use of intraoperative three-dimensional imaging are apparent, but indications for combined three-dimensional C-arm navigated procedures at the hip and knee joint are still limited. Future directions may include the use of digital flat-panel detectors and even robotic-controlled C-arm motion.

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.

A treatment protocol for abdomino-pelvic injuries

Background

Abdomino-pelvic injuries often present a challenge for the emergency department. Although literature reports several protocols on the treatment of abdomino-pelvic injuries aiming at defining the most advisable treatment line, optimal treatment is still controversial. This paper describes a protocol that has been used to treat abdomino-pelvic injuries in our hospital since 2002.

Materials and methods

In literature different protocol of abdomino-pelvic injuries are described and comparing them most of the difference are the timing of CT scan, the angiography and the laparotomy when treating a lesion of pelvic ring. If patient is haemodynamically instable and presents a lesion of pelvic ring our protocol suggest the simplest and fastest stabilization (pelvic external fixator) in emergency room and delay exam such as CT scan as second level exam. In the presence of an abdominal injury, with a positive focused assessment with sonography for trauma test, the first step should be a pelvic ring stabilization, as laparotomy decreases the abdominal pressure and reduces the tamponade effect on the retroperitoneum. According to presented protocol the angiography is not be a first choice treatment. This protocol was applied to 58 cases of abdomino-pevic injury with unstable pelvic lesions from October 2002 to December 2005. Mean injury severity score was 27.2 (CI  24.1–30.3).

Results

Five patients (8%) died, three due to haemorrhagic shock and two due to pulmonary embolization. Four patients (6.9%) had a partial or complete cauda equina syndrome, four patients (6.9%) complained of mild incontinence, whilst 1 (1.7%) complained of urinary retention with multiple cystitis. Two patients (3.4%) with retention and multiple cystitis, had a malunion and a painful non-union of the fracture. Seven patients (12.3%) had neurological impairment: 5 (8.6%) sciatic nerve palsy, 1 (1.7%) lumbosacral root lesions in a C2-type fracture and there was one case (1.7%) of inconstant lumbago with sciatic pain. Twelve patients reported different levels of sexual dysfunction (20.7%).

Conclusions

Although validation with a larger cohort is required, our preliminary clinical data are similar to, or better than, those reported in the most recent publications on this question, suggesting that this protocol could well reduce both the mortality rate and the long term complications of abdominopelvic injuries.

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.

A finite element model of electrode placement during stimulus evoked electromyographic monitoring of iliosacral screw insertion

Pelvic ring fractures that occur as a result of substantial orthopedic trauma are frequently repaired using iliosacral screws to stabilize the fracture. Stimulus evoked electromyography, using pulsed current stimuli provided through the drill bit cathode, has been advocated to prevent nerve root injury during iliosacral screw insertion. Our objective was to examine the effects of anode location, drill bit position, and anatomical structure on the nerve monitoring technique. A three-dimensional finite element model was constructed from computed tomography data to evaluate the effectiveness of five anode locations at four stations of drill bit insertion. Results indicate that the anode location should be at the midline or on the side contralateral to drill bit insertion. Locating the anode at other positions, such that the nerve root is outside of the primary electromagnetic field, leads to an attenuated electromyographic response that will ultimately lead to the failure of the monitoring technique.

Bilateral Sacroiliac Joint Dislocation in an Adolescent after a Skiing Accident

A bilateral sacroiliac joint (SI joint) dislocation is a rare injury pattern, in contrast to bilateral fracture dislocations of the SI joint. The incidence of pelvic dislocation of the SI joint without significant bone structural damage would most likely be observed in young children or adolescents after receiving a blunt, high energy impact. These young patients often suffer life threatening injuries to the intestines, neural or vascular systems or severe injury of the urinary tract. In these scenarios, plain projection radiographic imaging often leads to an inconclusive diagnosis making computer tomography indispensable to plan the treatment strategy. These strategies vary and the optimal approach is a subject to dispute. A surgical treatment of these injuries should ensure an immediate primary stability to allow early ambulation. The following study reports a unique trauma pattern with an isolated bilateral SI dislocation without fracture of the posterior or anterior pelvic ring nor concomitant injuries. This rare injury is a consequence of a pure vertical shear impact. This case report describes a technical pitfall of the iliolumbar transfixation and a solution to the problem. A dorso-ventro-dorsal approach, which utilizes both iliolumbar transfixation and ventral bilateral double plating osteosynthesis will be presented.

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.

Minimally invasive transiliac plate osteosynthesis for type C injuries of the pelvic ring: a clinical and radiological follow-up

OBJECTIVE

To evaluate radiological and functional outcome in patients treated with minimally invasive transiliac plate osteosynthesis for unstable pelvic injuries.

DESIGN

Retrospective analysis of a prospective treatment protocol in a consecutive patient series.

SETTING

Level 1 trauma center.

PATIENTS

Between January 1998 and December 2005, 31 patients with type C injuries of the pelvic ring were treated with minimally invasive transiliac plate osteosynthesis. According to the AO classification, 16 patients had a C1-injury, 9 had a C2 fracture, and 6 patients sustained a C3 injury of the pelvic ring. Anterior-posterior, inlet, and outlet radiographs were obtained preoperatively, immediately postoperatively, and during follow-up. Clinical outcome was determined according to the Hannover pelvic outcome score.

INTERVENTION

Posterior plate osteosynthesis for type C injuries of the pelvic ring.

MAIN OUTCOME MEASUREMENT

Preoperative and postoperative dislocation of the posterior pelvic ring, loss of reduction, implant failure, implant removal, clinical results of the pelvic injury and general limitations following the trauma.

RESULTS

Maximum average dislocation of the posterior pelvic ring was 16.1 mm preoperatively; postoperatively, it was 6.1 mm. A total of 23 patients (74.2%) could be followed up after an average of 20 months (range 7-57 months). Seven patients underwent follow-up treatment at other hospitals closer to their respective residences, whereas 1 patient passed away in the early postoperative phase due to multiorgan failure. Loss of reduction occurred in 2 cases. The clinical outcome regarding the pelvis was very good in 8 cases, good in 9 cases, fair in 4 cases, and poor in 2 cases. Social reintegration according to the Hannover pelvic outcome score was complete in 9 cases, poor in 10 cases, and incomplete in 10 cases.

CONCLUSION

Posterior plate osteosynthesis is a sufficiently stable method for the treatment of unstable pelvic ring injuries with a low risk of iatrogenic nervous tissue and vascular lesions. The disadvantages are limited reduction possibilities, the necessity of bilateral bridging of the sacroiliac joint in a unilateral injury, as well as a higher rate of symptomatic hardware.