Distraction External Fixation in Lateral Compression Pelvic Fractures

Does Fracture Pattern Really Predict Displacement of LC1 Sacral Fractures?

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

LEVEL OF EVIDENCE

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

Oblique anterior pelvic external fixator for intraoperative reduction of rotationally unstable pelvic ring injuries

Incomplete sacroiliac joint injuries are often associated with external rotation and extension deformities on the injured hemipelvis. To appropriately correct this deformity, an oblique reduction force from caudal to cranial and lateral to medial is helpful. These injuries are often associated with traumatic disruption of the pubic symphysis. However, in injuries without traumatic disruption to the pubic symphysis, a two-pin oblique anterior external fixator can be used to obtain and maintain reduction of the sacroiliac joint, while percutaneous fixation is subsequently placed. Through a small case series and three specific patient examples, we demonstrate that the oblique anterior external fixator frame is a simple and effective strategy with the reduction and stabilization process of these multiplanar hemipelvis deformities.

Combined Anterior-Posterior versus Posterior-Only Fixation of Stress-Positive Minimally Displaced Lateral Compression Type 1 (LC1) Pelvic Ring Injuries

OBJECTIVES

To compare hospital outcomes and late displacement between stress-positive minimally displaced lateral compression type 1 (LC1) pelvic ring injuries treated with combined anterior-posterior versus posterior-only fixation.

DESIGN

Retrospective comparative cohort.

SETTING

Urban level-one trauma center.

PATIENTS/PARTICIPANTS

LC1 injuries managed operatively.

INTERVENTION

Anterior-posterior versus posterior-only fixation.

MAIN OUTCOME MEASUREMENTS

Physical therapy (PT) clearance, discharge location, hospital length of stay (LOS), inpatient morphine equivalent doses (MED), and fracture displacement at follow-up.

RESULTS

Groups were similar in demographic and injury characteristics (age, high energy mechanism, ASA score, stress displacement, and rami/sacral fracture classifications). Anterior-posterior fixation resulted in longer operative times (median difference (MD): 27.0 minutes, 95% confidence interval (CI): 17.0 to 40.0, P < 0.0001) and had a trend of increased estimated blood loss (MD: 10 mL, CI: 0 to 30, P = 0.07). Patients with anterior-posterior fixation required less inpatient MEDs (MD: -180.0, CI: -341.2 to -15.0, P = 0.02), were more likely to clear PT by discharge (100% vs. 70%, proportional difference (PD): 30%, CI: 2.0%-57.2%, P = 0.02), were less likely to discharge to rehabilitation facilities (0% vs. 30%, PD: 30%, CI: 2.0%-57.2%, P = 0.02), and had a trend of less days to clear PT after surgery (MD: -1, CI: -2 to 0, P = 0.09) and decreased LOS (MD: -1, CI: -4 to 1, P = 0.17). Late fracture displacement did not differ between groups.

CONCLUSION

Anterior-posterior fixation of LC1 injuries was associated with an improved early hospital course-specifically, reduced inpatient opioid use and an increased number of patients who could clear PT and discharge home.

LEVEL OF EVIDENCE

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

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Management of LC Type I (LC-1) Pelvic Injuries with Complete Sacral Fracture: Comparison of Solitary Anterior Fixation with Combined Anterior-Posterior Fixation

BACKGROUND

Management of LC-1 type pelvic injuries, particularly in patients with complete sacral fracture (LC-1 PICSF, OTA type 61-B2.1), remains controversial. Specific indications for solitary fixation remain unclear, and there is a paucity of outcomes data in comparison to combined fixation. We undertook a retrospective study in patients with LC-1 PICSFs to compare outcomes between solitary anterior fixation and combined anterior-posterior fixation.

METHODS

A retrospective cohort study was conducted with enrollment from 2016 to 2018 at a single tertiary-referral center in China. Adults with operatively managed LC-1 PICSFs were enrolled. Patients with sacral displacement < 1 cm as assessed by axial CT received solitary anterior ring fixation (group A); patients with displacement ≥ 1 cm received combined fixation of both the anterior and posterior rings (group B). Reduction was confirmed by manipulation under anesthesia. Patients followed up for at least 24 months postoperatively. Primary outcome was function (Majeed score). Secondary outcomes included intraoperative characteristics, pain (VAS score), quality of fracture reduction (Tornetta and Matta radiographic grading), rate of nonunion, early weight-bearing status, and complication rate.

RESULTS

68 (89%) of 76 enrolled patients completed follow-up. Patients in group A exhibited improved operative times, less time under fluoroscopy, and less blood loss as compared to group B. There were no significant differences between groups A and B regarding quality of fracture reduction, rate of union, functional outcomes, or rate of complications. Notably, group B patients were more likely to achieve full early weight-bearing.

CONCLUSION

LC-1 PFCSFs can get benefits from ORIF; the treatment algorithm should be differently made following the degree of the sacral fractures displacement. Less than 1 cm sacral fracture displacement may get good functional outcomes from solitary anterior fixation. However, for the sacral fractures displacement greater or equal to 1 cm, both the anterior and posterior pelvic rings should be surgical stabilization.

Temporary External Fixation to Table as a Traction Reduction Aide in the Treatment of Unstable Pelvic Ring Injuries: A Technical Note

Displaced pelvic ring injuries can be challenging to even the experienced orthopedic traumatologist. A temporary external fixation to table construct provides a quick, simple, and accessible means of external skeletal fixation to reliably obtain and maintain stable hemipelvis reduction on the operating room table. The contralateral hemipelvis can be stabilized to the table by use of Steinman pins safely inserted into the subtrochanteric and anterior column regions and later connected to external fixator bars attached to the table. With rigid stabilization, the displaced contralateral pelvic fragment(s) can be reduced in a more vector intentional manner with greater force than the traditional means of pelvic reduction can allow. The skeletal-table fixation technique is presented along with two cases, a combined pelvic-acetabular injury and an isolated pelvic ring injury.

Stability of internal versus external fixation in osteoporotic pelvic fractures - a biomechanical analysis

INTRODUCTION

Osteoporosis-related fragility fractures of the pelvic ring (FFP) differ fundamentally from pelvic fractures in younger patients. However, very little is known about biomechanical stability of different osteosynthesis procedures addressing the anterior pelvic ring in these fractures. The aim of this study was to compare standard external fixation with internal fixation using a novel screw-and-rod system in osteoporotic fractures of the pelvic ring in terms of stiffness, plastic deformation and maximum load under cyclic loading in a human cadaveric model.

MATERIALS AND METHODS

A total of 18 embalmed osteoporotic cadaver pelvis specimens were randomized based on the T-score into a group for external fixation and a group for internal fixation. FFP type-IIB fractures were created. In addition to the external or internal fixator, a cement-augmented sacroiliac screw was implanted. Afterwards, axial cyclic loading was performed in a testing setup simulating one-leg stand.

RESULTS

Mean plastic deformation and stiffness both were significantly better in the internal fixation group than in the external fixation group (plastic deformation: 0.37 mm (SD: 0.23) versus 0.71 mm (SD: 0.26), p = 0.011; stiffness: 43.69 N/mm (SD: 18.39) versus 26.52 N/mm (SD: 9.76), p = 0.029). Maximum load did not differ significantly between internal fixator (506.3 N; SD: 129.4) and external fixator (461.1 N; SD: 147.4) (p = 0.515).

CONCLUSIONS

Submuscular internal fixation might be an interesting alternative to external fixation in clinical practice because of better biomechanical properties as well as several advantages in clinical use.

High-energy Lateral Compression Type 1 Injuries of the Pelvis: A Spectrum of Injury

Lateral compression type 1 pelvic fractures comprise a spectrum of injuries of varying stability. The clinician should be cognizant of signs and symptoms of instability including complete sacral fractures, bilateral ramus fractures, displacement greater than 1 cm, high-energy mechanism, and inability to bear weight. Management of these injuries is controversial, but the clinician should consider examination under anesthesia and potentially surgical stabilization.

Validated Radiographic Scoring System for Lateral Compression Type 1 Pelvis Fractures

OBJECTIVES

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

DESIGN

Survey study with validation patient cohort.

SETTING

Two Level 1 academic trauma centers.

PATIENTS/PARTICIPANTS

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

INTERVENTION

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

MAIN OUTCOME MEASUREMENT

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

RESULTS

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

CONCLUSIONS

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

Anterior subcutaneous internal fixator (INFIX) versus plate fixation for pelvic anterior ring fracture

The aim of this study was to compare the clinical outcomes in patients with unstable anterior pelvic ring fractures after treatment with anterior subcutaneous internal fixator (INFIX) or plate fixation. We performed a retrospective study from August 2015 to October 2017. A consecutive series of 74 patients who underwent surgical treatment of their anterior pelvic ring (35 treated with INFIX and 39 treated with plates) were studied. Data collected included patients’ demographic data, injury severity score (ISS), AO/OTA classification, injury mechanism, time to surgery, procedure time, and blood loss. The quality of postoperative reduction were assessed by postoperative radiographs using the Tornetta and Matta method. Functional outcome was evaluated using Majeed scoring system. In the INFIX group, ten patients developed LFCN paralysis, one patient suffered from superficial infection. Three screw loosening cases and two wound infection cases occurred in the plate group. INFIX is relatively minimally invasive and time-saving than the reconstruction plate in the treatment of anterior pelvic ring fracture. However, plate fixation increases the rate of anatomic reduction of the pelvic anterior ring fracture. Plates also provide a higher functional outcome compared with INFIX. INFIX is especially suitable in patients with urological injury, which can also decrease the wound infection rate.

Fixation Strategy Using Sequential Intraoperative Examination Under Anesthesia for Unstable Lateral Compression Pelvic Ring Injuries Reliably Predicts Union with Minimal Displacement

BACKGROUND

Examination under anesthesia (EUA) has been used to identify pelvic instability. Surgeons may utilize percutaneous methods for posterior and anterior pelvic ring stabilization. We developed an intraoperative strategy whereby posterior fixation is performed, with reassessment using sequential EUA to determine the need for anterior fixation. Our aim in the current study was to evaluate whether this strategy reliably results in union with minimal displacement.

METHODS

This was a multicenter retrospective study involving adult patients with closed lateral compression (LC) pelvic ring injuries treated during the period of 2013 to 2016. Included were patients who underwent percutaneous pelvic fixation based on sequential EUA. Data points included patient demographics, injury and fixation details, and displacement as observed on follow-up radiographs.

RESULTS

Complete documentation was available for 74 patients (mean age, 41 years). The mean duration of follow was 11 months. Fifty-three of the patients had LC-1 injuries, 19 had LC-2 injuries, and 2 had LC-3 injuries. Twenty-five (47.2%) of the 53 patients with LC-1 and 11 (57.9%) of the 19 patients with LC-2 injuries did not undergo anterior fixation on the basis of the algorithm. The 36 LC-1 or LC-2 patients who underwent combined anterior and posterior fixation had no measurable displacement at union. Of the 36 LC-1 or LC-2 patients with no anterior fixation, 27 with unilateral rami fractures had no measurable displacement at union. The remaining 9 LC-1 or LC-2 cases with no anterior fixation had bilateral superior and inferior rami fractures; each of these patients demonstrated displacement (mean, 7.5 mm; range, 5 to 12 mm) within 6 weeks of fixation that remained until union. All patients had protected weight-bearing for 12 weeks.

CONCLUSIONS

A fixation strategy based on sequential intraoperative EUA reliably results in union with minimal displacement for unstable LC pelvic ring injuries. Injuries requiring combined anterior and posterior fixation healed with no displacement. Those without anterior fixation and a unilateral ramus fracture healed with no displacement. In the presence of bilateral rami fractures, even with a negative finding on sequential EUA, the pelvis healed with 7.5 mm average displacement. Surgeons may consider anterior fixation to prevent this displacement.

LEVEL OF EVIDENCE

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

Study of the X-Ray Diagnosis of Unstable Pelvic Fracture Displacements in Three-Dimensional Space and its Application in Closed Reduction

ABSTRACTS Objective: To study the method of X-ray diagnosis of unstable pelvic fractures displaced in three-dimensional (3D) space and its clinical application in closed reduction.

METHODS

Five models of hemipelvic displacement were made in an adult pelvic specimen. Anteroposterior radiographs of the pelvis were analyzed in PACS. The method of X-ray diagnosis was applied in closed reductions. From February 2012 to June 2016, 23 patients (15 men, 8 women; mean age, 43.4 years) with unstable pelvic fractures were included. All patients were treated by closed reduction and percutaneous cannulate screw fixation of the pelvic ring. According to Tile's classification, the patients were classified into type B1 in 7 cases, B2 in 3, B3 in 3, C1 in 5, C2 in 3, and C3 in 2. The operation time and intraoperative blood loss were recorded. Postoperative images were evaluated by Matta radiographic standards.

RESULTS

Five models of displacement were made successfully. The X-ray features of the models were analyzed. For clinical patients, the average operation time was 44.8 min (range, 20-90 min) and the average intraoperative blood loss was 35.7 (range, 20-100) mL. According to the Matta standards, 7 cases were excellent, 12 cases were good, and 4 were fair.

CONCLUSIONS

The displacements in 3D space of unstable pelvic fractures can be diagnosed rapidly by X-ray analysis to guide closed reduction, with a satisfactory clinical outcome.

The use of external fixators in the definitive stabilisation of the pelvis in polytrauma patients: Safety, efficacy and clinical outcomes

OBJECTIVES

To analyse the complications and outcomes (functional/radiographic) of Pelvic External Fixators applied as part of the definitive fixation in polytrauma patients.

DESIGN

A single center retrospective chart review.

SETTING

A level-1 trauma center.

PATIENTS AND METHODS

We reviewed all the polytrauma patients (ISS>16) between 2007 and 2012 that had a PEF applied more than 30days. Complications including infection, aseptic loosening, neurological injury, loss of reduction, non-union and mal-union were recorded. Pelvic asymmetry and Deformity Index (DI) were measured at the immediate postoperative radiographs and final follow-up. The functional outcome at final follow up was estimated using a scale previously reported by Chiou et al.

RESULTS

59 patients with mean age of 38.4 (16 - 81) years and mean ISS score 28 (16- 66) were included. The PEFs were applied for mean duration of 56 (30-104) days. The average follow-up was 403days. 22 injuries were type B and 37 type C (AO/OTA). The most common symptomatic complications were pin site infection in 11 (18.6%) and loosening in 5 (8.5%) cases. 44 (74.5%) patients had satisfactory functional outcome. The immediate post-operative and final asymmetry and DI were compared between the two pelvic injury groups (type B and C fractures). The difference in displacement progression was more for type C injuries (p=0.034) but no correlation to the functional outcome was evident.

CONCLUSION

PEF can be used as definitive alternative stabilization method in specific situations at polytrauma setting. Radiological displacement occurred in both type B and C injuries but the clinical outcome was not correlated to this displacement. Complications related to PEF do not affect the final clinical outcome.

LEVEL OF EVIDENCE

Therapeutic Level III.

A Guide to Improving the Care of Patients with Fragility Fractures, Edition 2

Over the past 4 decades, much has been learned about the pathophysiology and treatment of osteoporosis, the prevention of fragility fractures, and the perioperative management of patients who have these debilitating injuries. However, the volume of published literature on this topic is staggering and far too voluminous for any clinician to review and synthesize by him or herself. This manuscript thoroughly summarizes the latest research on fragility fractures and provides the reader with valuable strategies to optimize the prevention and management of these devastating injuries. The information contained in this article will prove invaluable to any health care provider or health system administrator who is involved in the prevention and management of fragility hip fractures. As providers begin to gain a better understanding of the principles espoused in this article, it is our hope that they will be able to use this information to optimize the care they provide for elderly patients who are at risk of or who have osteoporotic fractures.

Femoral nerve palsy after pelvic fracture treated with INFIX: a case series

OBJECTIVE

The treatment of some pelvic injuries has evolved recently to include the use of a subcutaneous anterior pelvic fixator (INFIX). We present 8 cases of femoral nerve palsy in 6 patients after application of an INFIX to highlight this potentially devastating complication to pelvic surgeons using this technique and discuss how it might be avoided in the future.

DESIGN

Retrospective chart review. Case series.

SETTING

Five level 1 and 2 trauma centers, tertiary referral hospitals.

PATIENTS/PARTICIPANTS

Six patients with anterior pelvic ring injury treated with an INFIX who experienced 8 femoral nerve palsies (2 bilateral).

INTERVENTION

Removal of internal fixator, treatment for femoral nerve palsy.

MAIN OUTCOME MEASUREMENTS

Clinical and electromyographic evaluation of patients.

RESULTS

All 6 patients with a total of 8 femoral nerve palsies had their INFIX removed. Variable resolution of the nerve injuries was observed.

CONCLUSIONS

Application of an INFIX for the treatment of pelvic ring injury carries a potentially devastating risk to the femoral nerve(s). Despite early implant removal after detection of nerve injury, some patients had residual quadriceps weakness, disturbance of the thigh's skin sensation, and/or gait disturbance attributable to femoral nerve palsy at the time of early final follow-up.

LEVEL OF EVIDENCE

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

Internal anterior fixators for pelvic ring injuries: Do monaxial pedicle screws provide more stiffness than polyaxial pedicle screws?

OBJECTIVES

Little is known about the mechanical properties of internal anterior fixators (known as INFIX), which have been proposed as subcutaneous alternatives to traditional anterior external fixators for pelvic ring disruptions. We hypothesised that INFIX has superior biomechanical performance compared with traditional external fixators because the distance from the bar to the bone is reduced.

METHODS

Using a commercially available synthetic bone model, 15 unstable pelvic ring injuries were simulated by excising the pubic bone through the bilateral superior and inferior rami anteriorly and the sacrum through the bilateral sacral foramen posteriorly. Three test groups were established: (1) traditional supra-acetabular external fixation, (2) INFIX with polyaxial screws, (3) INFIX with monaxial screws. Load was applied, simulating lateral compression force. Outcome measure was construct stiffness.

RESULTS

The traditional external fixator constructs had an average stiffness of 6.21 N/mm ± 0.40 standard deviation (SD). INFIX with monaxial screws was 23% stiffer than the traditional external fixator (mean stiffness, 7.66 N/mm ± 0.86 SD; p = .01). INFIX with polyaxial screws was 26% less stiff than INFIX with monaxial screws (mean stiffness, 5.69 N/mm ± 1.24 SD; p = .05). No significant difference was noted between polyaxial INFIX and external fixators (mean stiffness, 6.21 N/mm ± 0.40 SD; p=.65).

CONCLUSIONS

The performance of INFIX depends on the type of screw used, with monaxial screws providing significantly more stiffness than polyaxial screws. Despite the mechanical advantage of being closer to the bone, polyaxial INFIX was not stiffer than traditional external fixation.

Operative agreement on lateral compression-1 pelvis fractures. a survey of 111 OTA members

OBJECTIVES

To better characterize operative agreement and disagreement among orthopaedic surgeons treating lateral compression type 1 (LC-1) pelvic fractures in an effort to improve communication between care providers and improve patient care.

DESIGN

Decision analysis.

SETTING

Level 1 trauma center.

METHODS

Twenty-seven LC-1 cases were selected to represent a wide array of LC-1 injuries. Each case was presented with 3 plain pelvic radiographs (anteroposterior, inlet, and outlet) and a scrollable computed tomography at the OTA national meeting. Attendees were queried whether they would perform operative stabilization "yes/no." Years of surgical practice (0-5, 6-10, and >10), annual pelvic fracture case volume (0-20, 21-50, and >50), and completion of a trauma fellowship (yes/no) were also collected. Fleiss' kappa (K) was used to measure operative agreement among survey respondents, where K = 0.21-0.40 was fair and K = 0.41-0.60 was moderate agreement.

RESULTS

One hundred eleven surgeons completed the survey where the average tendency to operate across surveys was 40%. Of the 27 cases presented, only 9 cases (33%) showed substantial agreement. There were 4 cases where nearly everyone chose operative stabilization (93.1%-94.4%) and 5 cases where nearly no one chose operative stabilization (0%-8.7%). The overall agreement was fair with K = 0.39 [95% confidence interval (CI), 0.34-0.44]. Although there was a trend for surgeons with more years of surgical practice to have a lower tendency to operate, it did not achieve statistical significance (odds ratio for >10 years vs. 0-5 years = 0.73; 95% CI, 0.48-1.11). Annual case volume and completion of a trauma fellowship were not statistically significant predictors of operative tendency.

CONCLUSIONS

Our results show only fair operative agreement (K = 0.39; 95% CI, 0.34-0.44) in a radiographic survey representing a broad range of LC-1 fracture morphologies among OTA surgeons. Only 9 of the 27 cases (33%) had substantial agreement. There was no difference in the decision to operate based on surgical volume, completion of a trauma fellowship, or time in practice. These results highlight the differing practice decisions among surgeons currently treating LC-1 injuries, and there is need for further studies to more fully understand stability after this injury pattern.

Is application of an internal anterior pelvic fixator anatomically feasible?

BACKGROUND

Spinal hardware has been adapted for fixation in the setting of anterior pelvic injury. This anterior subcutaneous pelvic fixator consists of pedicle screws placed in the supraacetabular region connected by a contoured connecting rod placed subcutaneously and above the abdominal muscle fascia.

QUESTIONS/PURPOSES

We examined the placement of the components for anterior subcutaneous pelvic fixator relative to key vascular, urologic, bony, and surface structures.

METHODS

We measured the CT scans of 13 patients after placement of the pelvic fixator to determine the shortest distances between the fixator components and important anatomic structures: the femoral vascular bundle, the urinary bladder, the cranial margin of the hip, the screw insertion point on the bony pelvis, the relationship between the pedicle screw and the corridor of bone in which it resided, and the position relative to the skin.

RESULTS

The average distance from the vascular bundle to the pedicle screw was 4.1 cm and 2.2 cm to the connecting rod. The average distance from the connecting rod to the anterior edge of the bladder was 2.6 cm. The average distance from the screw insertion point to the hip was 2.4 cm; none penetrated the hip. The average screw was in bone for 5.9 cm. The pedicle screws were on average 2.1 cm under the skin. The average distance from the anterior skin to the connecting rod was 2.7 cm.

CONCLUSIONS

Components of this anterior pelvic fixator are close to important anatomic structures. Careful adherence to the surgical technique should minimize potential risk.

LEVEL OF EVIDENCE

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

Treatment of unstable pelvic ring injuries with an internal anterior fixator and posterior fixation: initial clinical series

OBJECTIVES

To present a novel internal fixation device for stabilizing unstable pelvic fractures using supra-acetabular spinal pedicle screws and a subcutaneous connecting rod (INFIX).

SETTING

Level I trauma center.

DESIGN

Case series.

PATIENTS

Twenty-four patients with rotational or vertically unstable pelvic fractures that reported to a level I trauma center. METHODS/INTERVENTION: Surgical treatment of unstable pelvic fractures included reduction, appropriate posterior fixation where indicated, and an anterior subcutaneous internal fixator.

MAIN OUTCOME MEASUREMENT

Healing time, quality and loss of reduction, ease of nursing, incidence of complications, including nonunion, infection, and patient mobility and comfort.

RESULTS

In the present clinical series, all fractures healed without significant loss of reduction. There were no infections, delayed unions or nonunions. Nursing care was observed to be easier especially in the intensive care unit setting. Complications included unilateral anterior thigh paresthesias in 2 patients, and 1 patient each required repositioning of the pedicle screw and readjustment of screw rod junction. Patients tolerated the procedure well and were fairly mobile after the procedure.

CONCLUSIONS

The reported technique allows for a definitive and stable anterior fixation of vertically and rotationally unstable pelvic fractures when combined with the appropriate posterior fixation if indicated. The potential complications are acceptable with this technique and good outcomes were achieved. A second operative procedure is required for removal of the device. It is our view that its best indication is in obese individuals, in whom other options have shortcomings.

Young and burgess type I lateral compression pelvis fractures: a comparison of anterior and posterior pelvic ring injuries

The goals of this study were to find associations between anterior and posterior ring injuries, provide a descriptive comparison of pelvic ring disruptions as assessed by plain radiography, and compare the value of computed tomography (CT) over plain radiography in evaluating anterior and posterior structures. A retrospective review of radiographic reports and records identified 142 patients with pubic ramus fractures as observed by plain radiography. A statistical analysis was performed to test the associations between anterior ring injury as assessed by plain radiography and posterior ring injury as assessed by CT. Forty-five point five percent of patients with bilateral ramus fractures and 42.0% of patients with dual-ramus fractures had concomitant sacral fractures not observed on plain radiographs. These occult sacral fractures were found in only 11.1% of patients with inferior ramus fractures. The type of pubic injury on plain radiographs may be predictive of posterior ring injury, and therefore may help determine injury energy and severity, determine the need for further imaging studies, and help guide clinical management. Although CT is highly sensitive in identifying both anterior and posterior pubic ring injuries, elderly patients with simple fractures of a single pubic ramus are less likely to suffer from pelvic instability and thus may not benefit from CT.

Early experience with reduction of displaced disruption of the pelvic ring using a pelvic reduction frame

We describe our early operative experience with a new pelvic reduction frame and the standard of reduction of fractures of the pelvic ring which we achieved in the first 35 consecutive patients, with 34 acute fractures and one nonunion. The pre-operative and immediate post-operative radiographs were measured, using two methods, to find the maximum radiological displacement of the fracture and the quality of the reduction according to the criteria of Tornetta and Matta. There were 19 vertical shear fractures and 16 compression injuries. The mean age of the patients was 33.5 years (10 to 59) and mean delay to surgery was 4.6 days (0 to 16) in the 34 acute injuries. The mean operative time in isolated procedures was 103.4 minutes (SD 6.5). All but one patient had iliosacral screws implanted, 18 had screws in the anterior column, six had plates at the symphysis pubis and 12 had anterior external fixators. The mean maximum horizontal or vertical displacement was improved from 30.8 mm (SD 2.7) to a mean of 7.1 mm (SD 0.7). The reduction was assessed as excellent in ten patients, good in 18, and fair in the remainder. There was no significant influence on the quality of the reduction caused by obesity (p = 0.34), the type of fracture (p = 0.41) or delay to surgery (p = 0.83). The frame was shown to be effective, allowing the surgeon to obtain a satisfactory reduction and fixation of acute displaced disruptions of the pelvic ring.

What constitutes a Young and Burgess lateral compression-I (OTA 61-B2) pelvic ring disruption? A description of computed tomography-based fracture anatomy and associated injuries

OBJECTIVE

The objectives of this study were to provide computed tomography (CT)-based description of the anatomic specifics of lateral compression (LC)-1 pelvic ring disruptions and to describe injury severity to other body systems and their correlation with fracture anatomy.

DESIGN

Retrospective radiographic assessment and review of records

SETTING

A level 1 trauma and tertiary referral center.

PATIENTS/PARTICIPANTS

We identified a consecutive series of 100 patients with Young and Burgess LC-1 pelvic ring disruptions from the trauma registry database at a level 1 trauma center and evaluated their radiographs, CT scans, and injury and admission information.

INTERVENTION

None.

MAIN OUTCOME MEASUREMENTS

Presentation films were used to confirm injury type. The CT scan of the bony pelvis was reviewed for each patient by independent reviewers, with disagreement being resolved by the senior author. Sixteen categories were reviewed for each patient (rami fractures, segmental/comminuted rami fractures, Nakatani classification of rami fractures, anterior and posterior sacral fractures, and Denis classification). Sacral fractures were graded based on severity (0, no fracture; 1, buckle fracture; 2, simple fracture line; 3, comminuted fracture line). The age, Injury Severity Score (ISS), and 6 categories of Abbreviated Injury Scale (AIS) were recorded for each patient. A statistical analysis was performed to test the associations between fracture characteristics and injury severity.

RESULTS

Our group had 54 women and 46 men. The mean age was 37.84 +/- 1.95. All patients but 3 had 1 or more rami fractures, and all but 2 had a sacral fracture. Of the 116 superior rami fractures, Nakatani 3 was the most common type (60/116, 51.7%). Of the 217 rami fractures, 47 (21.7%) were segmental or comminuted. Of the 98 anterior sacral injuries, there were 9 (9.2%) buckle fractures, 39 (39.8%) simple fractures, and 50 (51.0%) comminuted fractures. Of these 98 anterior sacral injuries, 47 (48.0%) were complete, passing through the sacrum and exiting the posterior cortex. Increasing severity of anterior sacrum fracture was associated with the presence of a complete sacral fracture (P < 0.0001). Of the 98 sacral fractures, 50 (50.0%) were Denis type 1, 41 (41.8%) Denis type II, and 7 (7.1%) Denis type III. Higher Denis types had higher likelihood of complete fractures of the sacrum (P < 0.0001). There was a significant association between the presence of a comminuted rami fracture and a complete sacrum injury (P = 0.003) and a trend to higher rates in Nakatani 2 superior rami fractures (P = 0.169). There were 4 deaths due to trauma in this group, and the mean ISS score was 17.16 +/- 1.3. The highest mean system AIS score in these patients was extremity (2.42 +/- 0.06) followed by chest (1.28 +/- 0.17) and abdomen (1.03 +/- 1.30). There was a trend to higher mean ISS scores (P = 0.2287) and significantly higher abdominal AIS scores (P = 0.0014) in those with a complete sacral fracture. Those with comminuted and complete sacral fractures were more likely to be symptomatic and require posterior ring stabilization (P = 0.003 and 0.043, respectively)

CONCLUSIONS

LC-1 fractures of the pelvic ring represent a spectrum of injuries, with a large proportion having complete disruption of the sacrum. This complete injury of the sacrum is predicted by Denis type, severity of anterior ring disruption, abdominal AIS, and potentially location of rami fracture and ISS. CT scanning best defines these injuries.

Lateral compression fracture of the pelvis represents a heterogeneous group of complex 3D patterns of displacement

Although clinical and radiological criteria exist to direct the non-operative and operative treatment of other types of pelvic injuries, none exist for lateral compression (LC) fractures. The purpose of this study is to describe the patterns of injury in LC fractures through quantitative 3D radiographic analysis. It is hypothesised that LC fractures represent a spectrum of injuries with a combination of translational and rotational displacements. CT data from 60 patients with unilateral lateral compression fractures were obtained. Quantification of translations and rotations of the fractures was performed using 3D visualisation software. Fractures initially diagnosed as LC actually represent a spectrum of displacement patterns, ranging from a minimally displaced hemipelvis to complex combinations of displacements. Fractures were grouped based on pattern of rotation and translation into 5 distinct groups. 3D analysis of displacement patterns demonstrated a complexity in LC fractures which may explain the variations seen in outcomes associated with this injury.