Does Pelvic Embolization Increase Infection Rates in Patients Who Undergo Open Treatment of Acetabular Fractures?

Risk factors for surgical site infection following orthopaedic surgery for fracture by trauma: a nested case-control study

BACKGROUND

Surgical site infection (SSI) is associated with higher medical expenses and lower patient quality of life.

AIM

To identify specific modifiable risk factors for SSI after orthopaedic surgery for fractures caused by trauma.

METHODS

This nested case-control study used a nationwide trauma registry, the Japan Trauma Data Bank (JTDB) database. Patient data from 280 hospitals between January 2004 and May 2019 were retrieved from the JTDB. Patients with SSI and identified patients without SSI as control subjects were included, using propensity score matching adjusted for unmodifiable factors. Risk factors associated with SSI after orthopaedic trauma surgery were assessed using multi-level mixed-effects logistic regression models.

FINDINGS

In total, 15,910 patients were included in the analysis. Of these patients, 377 (2.4%) had SSI. After propensity score matching, 258 patients with SSI and 2580 matched patients without SSI were selected. In the multi-level mixed-effects logistic regression analysis, blood transfusion within 24 h (odds ratio (OR): 1.51; 95% confidence interval (CI): 1.06-2.13) was a significant risk factor for SSI following orthopaedic fracture surgery. The OR (95% CI) values for external fixation, transcatheter arterial embolization, and tourniquet for SSI following orthopaedic fracture surgery were 1.40 (0.96-2.03), 1.66 (0.81-3.38), and 2.99 (0.60-14.87), respectively.

CONCLUSION

These findings highlight the necessity of exercising caution when implementing blood transfusion within 24 h as a risk factor associated with SSI following orthopaedic trauma surgery.

Predictors of in-hospital surgical site infections in surgically managed acetabular fractures: A nationwide analysis

Background

A surgical site infection (SSI) rate of 4%-8% has been reported in patients who undergo open reduction and internal fixation (ORIF) for acetabular fractures. Studies have identified risk factors for SSI, but none have performed a nationwide analysis of SSI in surgically managed acetabular fracture patients.

Methods

The National Inpatient Sample (NIS) database was queried for patients who underwent ORIF for acetabular fractures from 2016 to 2019. Analysis was performed on all patients who underwent ORIF for acetabular fractures, as well as those who only underwent ORIF for isolated acetabular fractures. Clinical characteristics, hospital course, discharge disposition, and hospitalization costs were compared between groups. Multivariate regression analysis was conducted to assess predictors of SSI.

Results

41,725 patients undergoing acetabular fracture repair were identified, of which 490 (1.2%) developed SSI during hospitalization. Age (45.90 vs 49.90, p < 0.001) and Injury Severity Scale (5.99 vs 8.30, p < 0.001) were increased in patients who developed SSI. History of hypertension (HTN) (OR = 2.343, 95% CI 1.96-2.80, p < 0.001), longer hospital length of stay (30.27 days vs 10.00 days, p < 0.001) and total charges ($469,005 vs $193,032, p < 0.001) were associated with SSI. Lower rates of routine discharge were seen in SSI patients (OR = 0.333, 95% CI 0.260-0.426, p < 0.001). Higher rates of inpatient death were associated with SSI (OR = 2.210, 95% CI 1.172-4.17, p = 0.019). Multiple procedures in addition to acetabular fracture repair, iliac artery embolization, substance abuse, later time to internal fixation and HTN were predictive of SSI (p < 0.001).

Conclusions

Severity of injury, time to fixation, and factors associated with compromised cardiovascular integrity were predictors of SSI. Identifying patients at risk for SSI should lead to clinical maneuvers that may optimize outcome.

What are the risk factors for complications after combined injury of the pelvic ring and acetabulum?

PURPOSE

Combined acetabular and pelvic ring injuries represent a unique subset of pelvic trauma and little is known regarding their complications and outcomes. We sought to further evaluate these injury patterns and quantify their outcomes.

METHODS

A retrospective review at a single level 1 trauma center was performed on all patients with operatively treated combined ring and acetabulum injuries during a seven-year period. Main outcome measurements include all-cause complication including residual neurologic deficit, deep infection, conversion to total hip arthroplasty, deep venous thrombosis and mortality.

RESULTS

Seventy operatively treated combined ring and acetabulum patients with one-year follow-up were reviewed. The overall complication rate was 44%. Hip dislocation occurred in 40% of the cohort and was significantly associated with residual neurologic deficit and all-cause complication. Angiography with embolization was not associated with an increased rate of deep infection. Open acetabular approaches had a significantly higher complication rate compared to percutaneous procedures. Delay to definitive fixation greater than 36 h trended toward but did not reach association with all complications.

CONCLUSION

Combined injuries to the acetabulum and pelvic ring have high rates of complications. No individual fracture patterns were identified as risk factors, but hip dislocation was associated with an increased rate of complications. When possible, percutaneous reduction and fixation of acetabular fractures and early definitive fracture fixation lead to lower rates of complications. Use of angiography with embolization appears to be safe and does not increase the risk of infection or other complications.

Infection from an Iliosacral Screw 16 Years Postoperatively in Demolition Derby Umpire Crushed Between 2 Cars: A Case Report

CASE

A 47-year-old man crushed between 2 cars during a demolition derby, a nonracing North American motorsport, underwent open reduction and internal fixation, iliosacral screw fixation, arterial embolization, and multiple urologic procedures after massive pelvic ring injury, remarkably recovering nearly full function. Sixteen years after injury, he developed an abscess emanating from an iliosacral screw requiring irrigation, debridement, and hardware removal.

CONCLUSION

Deep surgical infections from iliosacral screws may present late, even more than 15 years after the original surgery. Obesity, preoperative embolization, diabetes, and urethral injuries are relevant risk factors. Similar patients should have a low threshold for infection workup when presenting with symptoms, even years after surgery.

Preoperative arterial embolization and wound complications after resection of malignant bone tumor in the pelvis: a nationwide database study

BACKGROUND

Massive intraoperative blood loss is common in pelvic malignant bone tumor surgery, and preoperative arterial embolization may be used in selected cases. Preoperative arterial embolization reportedly increases wound complications in pelvic fracture surgery, but little evidence is available regarding pelvic bone tumor surgery.

METHODS

Using a Japanese nationwide database (Diagnosis Procedure Combination database), we searched for patients who underwent pelvic malignant bone tumor surgery between July 2010 and March 2018. The primary endpoint was wound complications, defined as any wound requiring re-operation, negative pressure wound therapy or both. Univariate analyses (the chi-squared test for categorical variables, the unpaired t-test for continuous variables) and multivariate logistic regression analyses were performed to examine the association between preoperative arterial embolization and wound complications.

RESULTS

Among the 266 eligible patients, 43 (16%, 43/266) underwent embolization and 69 (26%, 69/266) developed wound complications. In the univariate analyses, preoperative arterial embolization (P < 0.001), duration of anesthesia (P < 0.001), the volume of blood transfusion (P < 0.001) and duration of indwelling drain tube (P < 0.001) were associated with wound complications. In the multivariate logistic regression analysis, preoperative arterial embolization was significantly associated with wound complications (odds ratio, 3.92; 95% confidence interval, 1.80-8.56; P = 0.001).

CONCLUSIONS

Preoperative arterial embolization may be associated with increased wound complications after pelvic malignant tumor surgery.

Pelvic Ring Resuscitation Pathways

A 35 year-old female is injured in a high-speed motor vehicle collision in which her car is struck on the driver's side by a distracted driver. The patient is unable to self-extricate from the vehicle and she is confused at the scene. She comes directly to the trauma bay via EMS and a binder is placed in transit for suspicion of a pelvic ring injury. Upon presentation she has a GCS of 14 due to confusion, and an initial pressure of 87/50. Workup does not disclose an associated head, chest or abdominal injury and the anteroposterior pelvis radiograph demonstrates a windswept pelvis injury pattern. Despite being transfused 4 units of whole blood, her hypotension does not improve. Please describe your institution's advanced resuscitation protocol and management of this scenario, and provide the rational and support for it.

Early hip survival after open reduction internal fixation of acetabular fracture

PURPOSE

To estimate survival of acetabular fracture repair by tracking patients across healthcare encounters. We hypothesized that hip survival estimated this way would be lower than reported by single-surgeon or single-center series not capturing censored reoperations.

METHODS

Retrospective health insurance administrative database cohort study. All claimed healthcare encounters for employer-sponsored health insurance beneficiaries aged 18-65 years without pre-existing hip pathology with a newly diagnosed acetabular fracture were identified between October 1, 2015, through December 31, 2018. The intervention was open reduction internal fixation of acetabular fracture during index admission. The primary outcome was survival of the acetabular fracture repair to subsequent reoperation by arthroscopy, arthrotomy for drainage of infection, implant removal, revision acetabular fixation, hip arthroplasty, hip resection, or arthrodesis.

RESULTS

38 reoperation procedures on the fractured acetabulum in 852 patients occurred within 2 years (incidence 4.5%). Total hip arthroplasty (2.5%) and revision internal fixation (1.5%) accounted for most early reoperations. Multivariable Cox regression identified an association between reoperation and increasing patient age (hazard ratio = 1.4 per decade, p < 0.01). The prevalence of any mental health condition was 29%.

CONCLUSIONS

Non-elderly adults with employer-sponsored insurance who sustain acetabular fractures have a greater burden of mental health disease than similarly insured patients without these injuries. Survival of the native acetabulum after fracture fixation exceeded 95% at 2 years and decreased with increasing patient age.

LEVEL OF EVIDENCE

Level III, Prognostic Study.

Does transarterial pelvic embolization have a negative effect on perioperative outcomes in pelvic ring injury and acetabular fracture?

OBJECTIVE

The purpose of this study was to determine whether TAE negatively impacted perioperative outcomes in patients who underwent open surgery for pelvic trauma.

METHODS

We retrospectively reviewed the medical records and radiographs of patients who had open surgery for an acute pelvic trauma between February 2014 and May 2017. The patients were classified into two groups: those who underwent TAE and those who did not. We evaluated preoperative demographics and perioperative outcomes between the two groups. Injury type-specific comparisons were also performed.

RESULTS

A total of 136 patients (50 TAE and 86 non-TAE) were included in this study. There were significant differences in preoperative demographics including the type of injury, injury severity score, revised trauma score, surgical approach, initial blood pressure, and the amount of transfusion within 24 h between the two groups. However, no differences in perioperative outcomes were identified except for the amount of total transfusion. There were significant differences between the two groups in the injury type-specific comparisons, specifically in the amount of transfusion within 24 h in patients with pelvic ring injury and in the injury severity score in patients with acetabular fracture. However, there was no difference in perioperative outcomes between the groups for either injury type.

CONCLUSION

In the present study, we were unable to identify negative effects of TAE on perioperative outcomes. Therefore, when considering open surgery subsequent to TAE, there is no evidence of increased risk for negative perioperative outcomes, especially with respect to bone healing and deep infection.

Risk Factors for Surgical Site Infection after Operative Fixation of Acetabular Fractures: Is Psoas Density a Useful Metric?

BACKGROUND

Surgical site infection (SSI) occurs in 5% to 7% of patients undergoing operative fixation of acetabular fractures, with reported risk factors including longer operative duration, increased blood loss, pelvic artery embolization, and concurrent abdominal organ injury, among others. Psoas muscle density is a measure of muscle quality and, as a metric for sarcopenia and/or nutrition status, has been associated with poor outcomes such as mortality across multiple surgical specialties. To date, psoas muscle density has not been explored for its associations with SSI in acetabular fracture patients.Questions/purposes (1) Is decreased psoas muscle density, as measured by Hounsfield units, associated with an increased SSI risk after acetabular fracture fixation? (2) What patient, operative, and hospital variables are associated with an increased SSI risk after acetabular fracture fixation?

METHODS

Between 2012 to 2017, surgeons performed 684 acetabular ORIF procedures at one level I trauma center. Of those, 8% (56 of 684) did not meet inclusion criteria, leaving 92% (n = 628) for analysis in this study. The median (range) follow-up duration was 12 months (0.5-77). Patient demographics, comorbidities, operative and in-hospital variables, and psoas muscle density measured using preoperative pelvic CT images-acquired for all operative acetabular fracture patients-were analyzed. SSI was defined by positive culture results obtained during irrigation and débridement. Overall, 7% (42 of 628) of patients had an SSI. A multivariable regression analysis was performed to identify independent risk factors. Sensitivity analysis was performed with minimum follow-up set at 3 months and 6 months.

RESULTS

There was no difference in the mean psoas muscle density between patients with SSI (50.9 ± 10.2 Hounsfield units [HUs]) and those who did not have an SSI within 1 year of open reduction and internal fixation (51.4 ± 8.1 HUs) (mean difference: 0.5 [95% confidence interval -2.34 to 3.32]; p = 0.69). Four variables were independently associated with an increased risk of SSI: increased operative time (1.04 [95% CI 1.00 to 1.07]; p = 0.03), estimated blood loss (1.08 [95% CI 1.02 to 1.14]; p = 0.01), female sex (2.34 [95% CI 1.19 to 4.60]; p = 0.01), and intravenous drug use (3.95 [95% CI 1.51 to 10.33]; p = 0.01). Sensitivity analysis showed no change in results using either 3-month or 6-month minimum follow-up.

CONCLUSIONS

Risk factors for SSI after acetabular fixation include female sex, intravenous drug use, prolonged operative times, and increased intraoperative blood loss. Although the density of the psoas muscle may be a surrogate for nutritional markers, it was not associated with SSI in our patients with acetabular fractures. Thus, it is not useful for risk assessment of SSI in the general population with acetabular fracture; however, future studies with larger sample sizes of patients older than 60 years may re-investigate this marker for SSI risk. Contrary to the results of previous studies, pelvic artery embolization, intraoperative blood transfusion, and intensive care unit stay did not increase the risk of SSI; however, we may have been underpowered to detect differences in these secondary endpoints. Future large, multisite studies may be needed to address these conflicting results more definitively.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Bilateral Internal Iliac Artery Embolization Results in an Unacceptably High Rate of Complications in Patients Requiring Pelvic/Acetabular Surgery

OBJECTIVES

To assess complication rates in patients undergoing open reduction internal fixation (ORIF) of pelvic/acetabular fractures with and without pelvic angiography embolization (PAE).

DESIGN

Retrospective case series.

SETTING

Level 1 Trauma Center.

PATIENTS/PARTICIPANTS

One hundred eleven patients with pelvic or acetabular fractures that required orthopaedic fixation.

INTERVENTION

Retrospective analysis of outcomes in patients who underwent ORIF of pelvic/acetabular fractures with and without PAE.

MAIN OUTCOME MEASUREMENTS

Comparison of surgical wound infections, necrosis, and/or fracture nonunions between the PAE group and a control group (no PAE).

RESULTS

Final study groups consisted of 50 patients in the PAE group and 61 patients in the control group. Ninety-six percent of patients underwent nonselective PAE. Significantly higher complications were noted in the PAE group than in the control group (20% compared with 4.9%; P = 0.020). In addition, posterior surgical approaches combined with internal iliac artery embolization represented the highest complication rate.

CONCLUSIONS

Patients requiring PAE and pelvic/acetabular ORIF should undergo a multidisciplinary treatment approach with the trauma surgeon, interventional radiologist, and orthopaedic surgeon before PAE being performed to decrease complications and avoid nonselective bilateral internal iliac artery embolization.

LEVEL OF EVIDENCE

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

Combat-related acetabular fractures: Outcomes of open versus closed injuries

INTRODUCTION

Since the onset of the Global War on Terror close to 50,000 United States service members have been injured in combat, many of these injuries would have previously been fatal. Among these injuries, open acetabular fractures are at an increased number due to the high percentage of penetrating injuries such as high velocity gunshot wounds and blast injuries. These injuries lead to a greater degree of contamination, and more severe associated injuries. There is a significantly smaller proportion of the classic blunt trauma mechanism typically seen in civilian trauma.

METHODS

We performed a retrospective review of the Department of Defense Trauma Registry into which all US combat-injured patients are enrolled, as well as reviewed local patient medical records, and radiologic studies from March 2003 to April 2012. Eighty seven (87) acetabular fractures were identified with 32 classified as open fractures. Information regarding mechanism of injury, fracture pattern, transfusion requirements, Injury Severity Score (ISS), and presence of lower extremity amputations was analyzed.

RESULTS

The mechanism of injury was an explosive device in 59% (n=19) of patients with an open acetabular fracture; the remaining 40% (n=13) were secondary to ballistic injury. In contrast, in the closed acetabular fracture cohort 38% (21/55) of fractures were due to explosive devices, and all remaining (n=34) were secondary to blunt trauma such as falls, motor vehicle collisions, or aircraft crashes. Patients with open acetabular fractures required a median of 17units of PRBC within the first 24h after injury. The mean ISS was 32 in the open group compared with 22 in the closed group (p=0.003). In the open fracture group nine patients (28%) sustained bilateral lower extremity amputations, and 10 patients (31%) ultimately underwent a hip disarticulation or hemi-pelvectomy as their final amputation level.

DISCUSSION

Open acetabular fractures represent a significant challenge in the management of combat-related injuries. High ISS and massive transfusion requirements are common in these injuries. This is one of the largest series reported of open acetabular fractures. Open acetabular fractures require immediate damage control surgery and resuscitation as well as prolonged rehabilitation due to their severity. The dramatic number of open acetabular fractures (37%) in this review highlights the challenge in treatment of combat related acetabular fractures.