Evaluating the stability of external fixators following pelvic injury: A systematic review of biomechanical testing methods

INTRODUCTION

This systematic review aims to identify previously used techniques in biomechanics to assess pelvic instability following pelvic injury, focusing on external fixation constructs.

METHODS

A systematic literature search was conducted to include biomechanical studies and to exclude clinical trials.

RESULTS

Of an initial 4666 studies found, 38 met the inclusion criteria. 84% of the included studies were retrieved from PubMed, Scopus, and Web of Science. The studies analysed 106 postmortem specimens, 154 synthetic bones, and 103 computational models. Most specimens were male (97% synthetic, 70% postmortem specimens). Both the type of injury and the classification system employed varied across studies. About 82% of the injuries assessed were of type C. Two different fixators were tested for FFPII and type A injury, five for type B injury, and fifteen for type C injury. Large variability was observed for external fixation constructs concerning device type and configuration, pin size, and geometry. Biomechanical studies deployed various methods to assess injury displacement, deformation, stiffness, and motion. Thereby, loading protocols differed and inconsistent definitions of failure were determined. Measurement techniques applied in biomechanical test setups included strain gauges, force transducers, and motion tracking techniques.

DISCUSSION AND CONCLUSION

An ideal fixation method should be safe, stable, non-obstructive, and have low complication rates. Although biomechanical testing should ensure that the load applied during testing is representative of a physiological load, a high degree of variability was found in the current literature in both the loading and measurement equipment. The lack of a standardised test design for fixation constructs in pelvic injuries across the studies challenges comparisons between them. When interpreting the results of biomechanical studies, it seems crucial to consider the limitations in cross-study comparability, with implications on their applicability to the clinical setting.

Predictors of long-term mortality in older patients with hip fractures managed by hemiarthroplasty: a 10-year study based on a population registry in Saxony, Germany

BACKGROUND

Mortality of patients with a femoral neck fracture is high, especially within the first year after surgery, but also remains elevated thereafter. The aim of this study was to identify factors potentially associated with long-term mortality in patients homogeneously treated with hemiarthroplasty for femoral neck fracture.

METHODS

This retrospective cohort study was performed at a single level 1 national trauma center at the university hospital of Leipzig (Saxony, Germany). The study time-window was January 1, 2010 to December 31, 2020. Primary outcome measure was mortality depending on individual patient-related characteristics and perioperative risk factors. Inclusion criteria was a low-energy femoral neck fracture (Garden I-IV) in geriatric patients 60 years of age or older that were primarily treated with bipolar hemiarthroplasty. Date of death or actual residence of patients alive was obtained from the population register of the eastern German state of Saxony, Germany. The outcome was tested using the log-rank test and plotted using Kaplan-Meier curves. Unadjusted and adjusted for other risk factors such as sex and age, hazard ratios were calculated using Cox proportional hazards models and presented with 95% confidence intervals (CI).

RESULTS

The 458 included patients had a median age of 83 (IQR 77-89) years, 346 (75%) were female and 113 (25%) male patients. Mortality rates after 30 days, 1, 5 and 10 years were 13%, 25%, 60% and 80%, respectively. Multivariate regression analysis revealed age (HR = 1.1; p < 0.001), male gender (HR = 1.6; p < 0.001), ASA-Score 3-4 vs. 1-2 (HR = 1.3; p < 0.001), dementia (HR = 1.9; p < 0.001) and a history of malignancy (HR = 1.6; p = 0.002) as independent predictors for a higher long-term mortality risk. Perioperative factors such as preoperative waiting time, early surgical complications, or experience of the surgeon were not associated with a higher overall mortality.

CONCLUSIONS

In the present study based on data from the population registry from Saxony, Germany the 10-year mortality of older patients above 60 years of age managed with hemiarthroplasty for femoral neck fracture was 80%. Independent risk factors for increased long-term mortality were higher patient age, male gender, severe comorbidity, a history of cancer and in particular dementia. Perioperative factors did not affect long-term mortality.

Early Stabilization Does Not Increase Complication Rates in Acetabular Fractures of the Elderly: A Retrospective Analysis from the German Pelvis Registry

Background: The incidence of acetabular fractures in geriatric patients has increased. Although there are strong data supporting the early operative treatment of hip fractures in geriatric patients, the optimal timing for acetabular fractures remains unclear and for several reasons, delayed treatment after trauma is common. Methods: A retrospective analysis of the German Pelvis Registry between 2008 and 2017 was performed. Ultimately, 665 patients with fractures of the anterior column or anterior column and posterior hemitransverse were enrolled. Patients above and below 65 years of age with these fracture types were analyzed regarding surgery day (within 48 hours, between 2 and 4 days, after 4 days), complication rate, reduction quality, and hospital stay. Results: The complication rate of the geriatric group was twice as high as that of younger patients; however, this finding was independent of the timing of surgery. Reduction quality and hospital stay were independent of surgical timing. Conclusions: In contrast to other fracture types, such as proximal femur fractures, the timing of surgery for acetabular fractures does not have a significant impact on the patient's outcome. The optimal time for surgery cannot be determined using the current data. However, as expected, there is a significantly higher risk for postoperative complications in the geriatric population.

Sacrospinous and sacrotuberous ligaments influence in pelvis kinematics

The alteration in mechanical properties of posterior pelvis ligaments may cause a biased pelvis deformation which, in turn, may contribute to hip and spine instability and malfunction. Here, the effect of different mechanical properties of ligaments on lumbopelvic deformation is analyzed via the finite element method. First, the improved finite element model was validated using experimental data from previous studies and then used to calculate the sensitivity of lumbopelvic deformation to changes in ligament mechanical properties, load magnitude, and unilateral ligament resection. The deformation of the lumbopelvic complex relative to a given load was predominant in the medial plane. The effect of unilateral resection on deformation appeared to be counterintuitive, suggesting that ligaments have the ability to redistribute load and that they play an important role in the mechanics of the lumbopelvic complex.

Primary stability of multi-hole cups compared to plate osteosynthesis in osteoporotic anterior column and posterior hemi-transverse acetabular fractures—A biomechanical comparison

Introduction

Acetabular fractures pose high demands on the surgeon and in the case of osteosynthetic treatment, anatomical reconstruction has the highest priority to achieve a good outcome. However, especially in older patients with poor bone quality, even anatomical reconstruction is no guarantee for a good clinical outcome and may nevertheless end in early osteoarthritis. Primary arthroplasty therefore has an increasing importance in the treatment of these patients. The aim of this study was to biomechanically compare fracture gap displacement and failure load as an assessment measure of the primary stability of conventional plate osteosynthesis with the treatment using a sole multi-hole cup for acetabular fractures.

Methods

Six hemi-pelvises each with anterior column and posterior hemi-transverse (ACPHT) fracture were treated with either plate osteosynthesis or a multi-hole cup. The tests were carried out in a standardised test set-up with cyclic loading in various stages between 150 N and 2500 N. The fracture gap displacement was recorded with optical 3D measuring and the failure load was determined after the cyclic measurement.

Results

With increasing force, the fracture gap displacement increased in both procedures. In each group there was one treatment which failed at the cyclic loading test and a bone fragment was broken out. The primary stability in arthroplasty was comparable to that of the standard osteosynthesis.

Conclusions

The results found seem promising that the primary arthroplasty with a sole multi-hole cup and corresponding screw fixation achieves an initial stability comparable to osteosynthesis for typical ACPHT fractures. However, further clinical studies are needed to prove that the cups heal solidly into the bone.

Pararectus approach vs. Stoppa approach for the treatment of acetabular fractures - a comparison of approach-related complications and operative outcome parameters from the German Pelvic Registry

PURPOSE

The Pararectus approach has been introduced as an alternative anterior approach to the Stoppa approach in acetabular surgery. There is no evidence which approach should be preferred, especially regarding approach-related complications. Therefore, aim of this registry study was to compare the Pararectus approach to the Stoppa approach regarding complications and quality of reduction.

METHODS

Patients from the German Pelvic Registry with a surgically treated acetabular fracture, either through the Pararectus approach or the Stoppa approach, were analyzed or compared regarding demographic, clinical and operative parameters.

RESULTS

In total, 384 patients with an acetabular fracture received a surgical procedure with either the Pararectus approach (n=120) or the Stoppa approach (n=264). There were no differences between the two groups regarding demographic parameters and fracture pattern. The overall complication rate (35.0% vs. 31.4%), the mortality rate (5.0% vs. 3.0%) and the osteosynthesis-associated complication rate (5.8% vs. 4.2%) tended to be higher in the Pararectus group with no statistical significance. There were significantly more anatomical reductions in the Pararectus group (56% vs. 43%; p=0.01). However, operation time was significantly longer in the Pararectus group (255±125 vs. 205±103 minutes; p<0.001).

CONCLUSION

Despite a longer operation time, the Pararectus approach and the Stoppa approach are equivalently applicable for the treatment of acetabular fractures regarding complication rates and quality of reduction.

LEVEL OF EVIDENCE

III, retrospective comparative study.

Patients with combined pelvic and spinal injuries have worse clinical and operative outcomes than patients with isolated pelvic injuries analysis of the German Pelvic Registry

Background

Pelvic fractures are often associated with spine injury in polytrauma patients. This study aimed to determine whether concomitant spine injury influence the surgical outcome of pelvic fracture.

Methods

We performed a retrospective analysis of data of patients registered in the German Pelvic Registry between January 2003 and December 2017. Clinical characteristics, surgical parameters, and outcomes were compared between patients with isolated pelvic fracture (group A) and patients with pelvic fracture plus spine injury (group B). We also compared apart patients with isolated acetabular fracture (group C) versus patients with acetabular fracture plus spine injury (group D).

Results

Surgery for pelvic fracture was significantly more common in group B than in group A (38.3% vs. 36.6%; p = 0.0002), as also emergency pelvic stabilizations (9.5% vs. 6.7%; p < 0.0001). The mean time to emergency stabilization was longer in group B (137 ± 106 min vs. 113 ± 97 min; p < 0.0001), as well as the mean time until definitive stabilization of the pelvic fracture (7.3 ± 4 days vs. 5.4 ± 8.0 days; p = 0.147). The mean duration of treatment and the morbidity and mortality rates were all significantly higher in group B (p < 0.0001). Operation time was significantly shorter in group C than in group D (176 ± 81 min vs. 203 ± 119 min, p < 0.0001). Intraoperative blood loss was not significantly different between the two groups with acetabular injuries. Although preoperative acetabular fracture dislocation was slightly less common in group D, postoperative fracture dislocation was slightly more common. The distribution of Matta grades was significantly different between the two groups. Patients with isolated acetabular injuries were significantly less likely to have neurological deficit at discharge (94.5%; p < 0.0001). In-hospital complications were more common in patients with combined spine plus pelvic injuries (groups B and D) than in patients with isolated pelvic and acetabular injury (groups A and C).

Conclusions

Delaying definitive surgical treatment of pelvic fractures due to spinal cord injury appears to have a negative impact on the outcome of pelvic fractures, especially on the quality of reduction of acetabular fractures.

A computed tomography based survey study investigating the agreement of the therapeutic strategy for fragility fractures of the pelvis

Treatment recommendations for fragility fractures of the pelvis (FFP) have been provided along with the good reliable FFP classification but they are not proven in large studies and recent reports challenge these recommendations. Thus, we aimed to determine the usefulness of the FFP classification determining the treatment strategy and favored procedures in six level 1 trauma centers. Sixty cases of FFP were evaluated by six experienced pelvic surgeons, six inexperienced surgeons in training, and one surgeon trained by the originator of the FFP classification during three repeating sessions using computed tomography scans with multiplanar reconstruction. The intra-rater reliability and inter-rater reliability for therapeutic decisions (non-operative treatment vs. operative treatment) were moderate, with Fleiss kappa coefficients of 0.54 (95% confidence interval [CI] 0.44–0.62) and 0.42 (95% CI 0.34–0.49). We found a therapeutic disagreement predominantly for FFP II related to a preferred operative therapy for FFP II. Operative treated cases were generally treated with an anterior–posterior fixation. Despite the consensus on an anterior–posterior fixation, the chosen procedures are highly variable and most plausible based on the surgeon’s preference.

The pectineal ligament is a secondary stabilizer in anterior pelvic ring fractures - a biomechanical study

BACKGROUND

There is ongoing discussion whether operative fixation of partially stable lateral compression fractures of the pelvis is beneficial for the patient. Recent studies suggest that the pectineal ligament may act as a secondary stabilizer of the anterior pelvis ring. The purpose of this study was to investigate the influence of the pectineal ligament's integrity on the biomechanical stability and displacement in anterior pelvic ring fractures.

METHODS

In a biomechanical setup, a cyclic loading protocol was applied with sinusoidal axial force from 100 to 500 N on cadaver hemipelves with soft tissues (n = 5). After testing the native specimens ("No fracture"), increasing degrees of injury were created on the samples: 1. an osseous defect to the pubic ramus ("Bone #"), 2. cutting of all soft tissues including obturator membrane except for the pectineal ligament intact ("ObtM #"), 3. cutting of the pectineal ligament ("PectL #") - with the loading protocol being applied to each sample at each state of injury. Fracture motion and vertical displacement were measured using a digital image correlation system and opto-metric analysis.

RESULTS

No failure of the constructs was observed. Creating a pubic ramus fracture (p = 0.042) and cutting the pectineal ligament (p = 0.042) each significantly increased relative fracture movement. The mean change in absolute movement was 0.067 mm (range, 0.02 mm to 0.19 mm) for ObtM # and 0.648 mm (range, 0.07 mm to 2.93 mm), for PectL # in relation to Bone # (p = 0.043). Also for absolute vertical movement, there was a significant change when the pectineal ligament was cut (p = 0.043), while there was no such effect with cutting all other soft tissues including the obturator membrane.

CONCLUSIONS

Based on the findings of this in vitro study, the pectineal ligament significantly contributes to the stability of the anterior pelvic ring. An intact pectineal ligament reduces fracture movement in presence of a pubic ramus fracture.

Evaluation of decision-making in the treatment of acetabular fractures

Treatment of acetabular fractures is challenging and risky, especially when surgery is performed. Yet, stability and congruity of the hip joint need to be achieved to ensure early mobilization, painlessness, and good function. Therefore, coming up with an accurate decision, whether surgical treatment is indicated or not, is the key to successful therapy.

Data from the German pelvic Trauma Registry (n  = 4213) was evaluated retrospectively, especially regarding predictors for surgery. Furthermore, a logistic regression model with surgical treatment as the dependent variable was established.

In total, 25.8% of all registered patients suffered from an acetabular fracture and 61.9% of them underwent surgery. The fracture classification is important for the indication of surgical therapy. Anterior wall fractures were treated surgically in 10.2%, and posterior column plus posterior wall fractures were operated on in 90.2%. Also, larger fracture gaps were treated surgically more often than fractures with smaller gaps (>3 mm 84.4%, <1 mm 20%). In total, 51.4% of women and 66.0% of men underwent surgery. Apart from the injury severity score (ISS), factors that characterize the overall picture of the injury were of no importance for the indication of a surgical therapy (isolated pelvic fracture: 62.0%, polytrauma: 58.8%). The most frequent reason for non-operative treatment was ‘minimal displacement’ in 42.2%.

Besides fracture classification and fracture characteristics, no factors characterizing the overall injury, except for the ISS, and unexpectedly gender, are important for making a treatment decision. Further studies are needed to determine the relevance of these factors, and whether they should be used for the decision-making process, in particular surgeons with less experience in pelvic surgery, can orient themselves to.

Percutaneous operative treatment of fragility fractures of the pelvis may not increase the general rate of complications compared to non-operative treatment

Purpose

Despite an increasing number of fragility fractures of the pelvis (FFP) over the last 2 decades, controversy persists on their therapy with special regard to potential complications. Therefore, the present study compared the complication rates and in-hospital mortality of non-operative therapy, percutaneous treatment and open reduction and internal fixation (ORIF) of pelvic fractures in elderly patients.

Methods

All consecutive patients treated for FFP between January 2013 and December 2017 aged 65 years or older were retrospectively identified from an institutional database. Demographic data and specific patient data were collected with a special focus on pre-existing comorbidities. General and surgical complications, hospital length of stay (LOS) and mortality rates were compared.

Results

379 patients (81.3 ± 7.5 years; 81% female) were identified, 211 (55.7%) were treated non-operatively, 74 (19.5%) percutaneously and 94 (24.8%) with ORIF. The rate of general complications did not differ between treatment groups (non-operative: 21.8%; percutaneous: 28.4%; ORIF: 33.0%; p = 0.103). Surgery-related complications were twofold more frequent in the ORIF group as than in the percutaneously treated group (18.1% vs. 9.5%). The LOS differed significantly (non-operatively: 8.9 ± 7.1 days; percutaneous: 16.6 ± 8.2 days; ORIF: 19.3 ± 12.8 days; p < 0.001). Hospital mortality rate was higher in patients with ORIF (5.3%) than percutaneous treatment (0%) (p = 0.044).

Conclusions

Complication rates and hospital mortality in elderly patients with FFPs are high and associated with long LOS. For surgical treatment of FFPs, the complication rate and mortality can be significantly reduced using percutaneous procedures compared to ORIF. Therefore, percutaneous surgery should be preferred where possible.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00068-021-01660-w.

Knee arthrodesis as last resort for persistent knee joint infections : Comparison of extramedullary and intramedullary treatment

Background

Knee joint arthrodesis is an established treatment for periprosthetic infections (PPI) providing stability and pain relief. In this study the outcome after arthrodesis of the knee joint for persistent infections was compared and evaluated depending on the surgical procedure (intramedullary vs. extramedullary).

Material and methods

In a retrospective case analysis, all patients who underwent knee joint arthrodesis between 1 January 2010 and 31 December 2016 were identified and divided into two groups: IMA and EMA. All patients were examined clinically and radiologically and the patient files were evaluated. In addition, the FIM score, the LEFS, the WHOQOL-BREF and NRS were evaluated.

Results

The median LEFS score for the IMA group was 26 points and in the EMA group 2 points (p = 0.03). The IMA patients showed a median pain scale at rest of 0 and during exercise of 2. The EMA group recorded a pain scale of 3 at rest and 5 during exercise (p = 0.28 at rest; p = 0.43 during exercise). In the IMA group the median postsurgical leg length difference was −2.0 cm and −2.5 cm in the EMA group (p = 0.31). At the end of the follow-up examinations, the FIM score of patients in the IMA group was 74.5 points and 22 points in the EMA group (p = 0.07).

Conclusion

The study showed that no arthrodesis procedure is obviously superior with respect to the postoperative outcome. The IMA combines advantages especially in the early phase after surgery in terms of function as well as patient comfort and is therefore currently the procedure of choice. The attending physician should be familiar with the advantages and disadvantages of the various procedures in order to be able to make an individual decision and thus maximize the chance of treatment success.

A comparison on the detection accuracy of ante mortem computed tomography vs. autopsy for the diagnosis of pelvic ring injury in legal medicine

A detailed knowledge on the exact morphology of pelvic injuries provided crucial information in understanding the mechanisms of injury and has influence on the natural course and subsequent mortality. However, forensic medical literature investigating pelvic fractures in detail is scarce to date. This case series aims to compare the accuracy in detecting pelvic injuries using autopsy and ante mortem computed tomography (CT). Nineteen deceased patients with CT scans of pelvic fractures were included retrospectively. Pelvic injuries were independently assessed by a board-certified radiologist (R) and a board-certified trauma surgeon (T), both using the ante mortem CT scans, and by a board-certified forensic pathologist using autopsy (A) results without knowledge of the CT scan findings. No patient had died causatively from a pelvic fracture. Most injuries of the pelvis were present in the pubic rami (16/18) and sacral bone (13/18), followed by the sacroiliac joint (9/18) and iliac bone fractures (8/18). Ilium fractures (A:100%;R:67%;T:67%) and injuries of the sacroiliac joint (A:83%;R:50%;T:42%) were best detected via autopsy. The diagnosis of sacral fractures (A:19%;R:94%;T:88%) and fractures of the pubic rami (A:67%;R:96%;T:96%) were most often missed in autopsy. The results show deficits in the assessment of the pelvic injury for both CT and autopsy. Autopsy was superior in detecting injuries of the sacroiliac joint, but inferior in detecting sacral and pubic bone fractures. For an encompassing evaluation of ligamento-skeletal pelvic injuries, the complementary use of both CT and autopsy is recommended.

Comparison of pelvic C-clamp and pelvic binder for emergency stabilization and bleeding control in type-C pelvic ring fractures

Severe bleeding is the major cause of death in unstable pelvic ring fractures. Therefore, a quick and efficient emergency stabilization and bleeding control is inevitable. C-clamp and pelvic binder are efficient tools for temporary bleeding control, especially from the posterior pelvic ring. Yet the C-clamp requires more user knowledge, training and equipment. However, whether this makes up for a more efficient bleeding control, is still under debate. Patients with a type-C pelvic ring fracture were identified from the German Pelvic Registry (GPR) and divided into three groups of 40 patients (1. no emergency stabilization, 2. pelvic binder, 3. C-clamp). The matching occurred according to the parameters age, gender, initial RR and initial HB. Complication-and mortality rates were compared especially regarding bleeding control. Regarding ISS and fracture dislocation there was no difference. The use of the C-clamp resulted in more complications, a higher mortality rate due to severe bleeding and more blood transfusions were admitted. Moreover the pelvic binder was established noticeably faster. However, the C-clamp was more often rated as effective. There is no evidence of advantage comparing the C-clamp to the pelvic binder, regarding bleeding control in type-C pelvic ring fractures. In fact, using the pelvic binder even showed better results, as the time until established bleeding control was significantly shorter. Therefore, the pelvic binder should be the first choice. The C-clamp should remain a measure for selected cases only, if an adequate bleeding control cannot be achieved by the pelvic binder.

Integrity of the pectineal ligament in MRI correlates with radiographic superior pubic ramus fracture displacement

BACKGROUND

Estimating the stability of pelvic lateral compression fractures solely by static radiographs can be difficult. In this context, the role of anterior pelvic soft tissues as potential secondary stabilizer of the pelvic ring has hardly been investigated.

PURPOSE

To correlate the initial radiographic appearance of the pubic ramus fracture with the integrity of the pectineal ligament, a strong ligament along the pecten pubis.

MATERIAL AND METHODS

In total, 31 patients with a pelvic lateral compression fracture (AO/OTA 61- B1.1/B2.1) with 33 superior pubic ramus fractures and available post-traumatic radiographs (pelvis anteroposterior, inlet, outlet) and magnetic resonance imaging (MRI) of the pelvis with fat-suppressed coronal images were reviewed retrospectively. Radiographic superior pubic ramus fracture displacement was measured and correlated to the degree of MR-morphologic alterations of the pectineal ligament (grade 0 = intact, grade 3 = rupture).

RESULTS

In the majority of fractures (72.7%), associated MR-morphologic alterations of the pectineal ligament were present. Radiographic displacement and MRI grading showed a strong positive correlation (Spearman rho = 0.783, P < 0.001). The sensitivity and specificity for a radiographic displacement of >3 mm on plain radiographs to detect a structural ligament lesion on MRI (grade 2 and higher) were 73% and 100%, respectively.

CONCLUSION

Radiographic displacement of superior pubic ramus fractures >3 mm is a strong indicator for a structural lesion of the pectineal ligament. Future studies should investigate the potential biomechanical importance of this ligament for pelvic ring stability.

The influence of different sample preparation on mechanical properties of human iliotibial tract

In the run-up to biomechanical testing, fresh human tissue samples are often frozen in order to inhibit initial decomposition processes and to achieve a temporal independence of tissue acquisition from biomechanical testing. The aim of this study was to compare the mechanical properties of fresh tissue samples of the human iliotibial tract (IT) to fresh-frozen samples taken from the same IT and those modified with different concentrations of Dimethylsulfoxide (DMSO) prior to freezing. All samples were partial plastinated and destructive tensile tests were conducted with a uniaxial tensile test setup. A plastination technique already established in the laboratory was modified to improve the clamping behaviour of the samples. Material failure was caused by a gradual rupture of the load-bearing collagen fibre bundles. Contrary to our expectations, no significant difference was found between the tensile strength of fresh and fresh frozen specimens. The addition of 1 wt% DMSO did not increase the tensile strength compared to fresh-frozen samples; an addition of 10 wt% DMSO even resulted in a decrease. Based on our findings, the use of simple fresh-frozen specimens to determine the tensile strength is viable; however fresh specimens should be used to generate a complete property profile.

Minimally displaced acetabulum fractures in geriatric patients: a comparison of open, percutaneous and non-operative treatment from the German Pelvic Injury Register data

Purpose

In elderly patients with minimally displaced acetabulum fractures, the patients’ inability to partially weight-bear and the need for early mobilisation may trigger the decision towards a treatment with higher primary stability. The purpose of this study was to compare open reduction and internal fixation (ORIF), closed reduction and percutaneous fixation (CRPIF) and non-operative treatment in geriatric minimally displaced acetabulum fractures with regard to complications and quality of reduction.

Methods

Data from the prospective German Pelvic Injury Register collected between 2008 and 2018 were used to evaluate 608 geriatric patients with isolated minimally displaced (≤ 5 mm) acetabulum fractures. In total, 429 received non-operative treatment, 117 ORIF and 62 CRPIF. Demographics, injury severity, fracture pattern, complications and fracture displacement before and after treatment were analysed.

Results

Both operative methods reduced fracture gap displacement. CRPIF was associated with lower blood loss and shorter operative time compared to ORIF (p < 0.001). Hospital stay was 12.9 days in the non-operative group, 16.8 with CRPIF and 23.6 with ORIF (p < 0.001). Non-surgical general complications were more likely to occur following ORIF (22.2%) compared to CRPIF (8.1%) and non-operative treatment (8.4%, p < 0.001). The rate of surgical complications was not different for ORIF and CRPIF (p = 0.122)

Conclusion

Both operative treatments improve fracture displacement and joint congruency in elderly patients with minimally displaced acetabulum fractures. Compared to ORIF, CRPIF achieves similar quality of reduction but is associated with fewer complications, smaller intraoperative blood loss, shorter operative time and shorter length of hospital stay.

Mortality, complications and long-term functional outcome in elderly patients with fragility fractures of the acetabulum

Background

Early operative treatment of acetabulum fractures in geriatric patients has been suggested to reduce pain and allow for earlier mobilization. The aim of this study was to determine mortality, complications and functional outcome after operative and non-operative treatment.

Methods

Patients aged ≥60 years with operative treatment of low-energy fragility fracture of the acetabulum from 2009 to 2016 and a follow-up of at least 24 months were identified. The patients were contacted by phone and a modified Merle d’Aubigné score was obtained. If patients or their relatives were not available for follow-up, mortality data was assessed using a national social insurance database.

Results

One hundred seventy-six patients (mean age 78, SD 10 years; 73 female) were available for analysis of mortality data. At final follow-up (68 months, SD 26, range, 24 to 129), 99/176 patients (56.3%) had deceased. One-year-mortality was 25.0% and 2-year mortality 35.8%. Type of treatment (non-operative vs. operative) did not affect mortality at 1 and 2 years (p = .65 and p = .10). Hospital-acquired infections were observed in 31/176 cases (17.6%), thromboembolic events and delirium in 6 patients (3.4%). In-hospital mortality was 5.7%. Patients who underwent operative treatment were more likely to have an in-hospital infection (p = .02) but less likely to sustain thromboembolic events (p = .03).

The mean hospital stay was 14 days (SD 10 days, range, 1 to 66). Patients with operative treatment were longer hospitalized than patients with non-operative treatment (p < .001).

The rate of secondary conversions to THA was 12.4%, this was not affected by initial treatment.

The mean modified Merle d’Aubigné Score of those patients available for a final follow-up (n = 47; follow-up 56 months, SD 28, range, 24 to 115) was 14/18 points, SD 3 (range 7 to 18). Functional results at final follow-up between operatively and non-operatively treated patients were without difference.

Conclusions

All-cause mortality and in-hospital complications are high among geriatric patients with low-energy fractures of the acetabulum even when treated operatively. Secondary conversion rates to THA are similar to those seen in younger patients. Mid-term functional outcome in those surviving is fair.

Time-to-treatment is a risk factor for the development of pressure ulcers in elderly patients with fractures of the pelvis and acetabulum

INTRODUCTION

Fractures of the pelvis and acetabulum are associated with pain and immobilization and, hence, pose the risk of developing a pressure ulcer - especially in elderly patients. In the literature, information on risk factors for the occurrence of pressure ulcers related to geriatric pelvic or acetabulum fractures is missing.

METHODS

Consecutive in-hospital patients aged 55 years or older treated for closed pelvis and/or acetabulum fractures between 2013 and 2017 were retrospectively identified from an institutional prospective database. Epidemiologic characteristics and patient specifics with special focus on the time from admission to treatment, duration of hospitalization and comorbidities were retrospectively assessed by chart review.

RESULTS

During the evaluated interval, 407 patients with isolated fractures of the pelvis or acetabulum (mean age 78 years, range 55 to 101 years, 69,3% female) were treated. A new pressure ulcer that developed during the hospitalization was observed in 46/407 patients (11.3%). This included pressure ulcers of stage 1 in 18/46 cases (39%), stage 2 in 24/46 cases (52%), and stage 3 in 4/46 cases (9%). No stage 4 ulcers were seen in this cohort. The mean duration of hospitalization was longer in patients with a pressure ulcer (25 days, SD 17) than in patients with no ulcers (12 days, SD 9; p < .001). Patients who developed a pressure ulcer, had waited significantly longer for treatment of their pelvis/acetabulum fracture when compared to patients without an ulcer (5 days, SD 5 vs. 3 days SD 4, p = =.001). A logistic regression analysis confirmed "time to treatment" as an independent risk factor for the occurrence of a pressure ulcer during hospitalization. In an analysis adjusted for the confounders age, male gender, diabetes and malignancy, the odds ratio to develop a pressure ulcer remained 1.10 (CI 1.03 to 1.19; c-value = 0.774, p = .008) for each day of waiting treatment.

CONCLUSION

"Time to treatment" is an independent risk factor for the occurrence of a pressure ulcer during hospitalization after a pelvis/acetabulum fracture in elderly patients. Each day of waiting treatment increases the risk of developing a pressure ulcer by 10%.

Associated abdominal injuries do not influence quality of care in pelvic fractures-a multicenter cohort study from the German Pelvic Registry

Background

Pelvic fractures are rare but serious injuries. The influence of a concomitant abdominal trauma on the time point of surgery and the quality of care regarding quality of reduction or the clinical course in pelvic injuries has not been investigated yet.

Methods

We retrospectively analyzed the prospective consecutive cohort from the multicenter German Pelvic Registry of the German Trauma Society in the years 2003–2017. Demographic, clinical, and operative parameters were recorded and compared for two groups (isolated pelvic fracture vs. combined abdominal/pelvic trauma).

Results

16.359 patients with pelvic injuries were treated during this period. 21.6% had a concomitant abdominal trauma. The mean age was 61.4 ± 23.5 years. Comparing the two groups, patients with a combination of pelvic and abdominal trauma were significantly younger (47.3 ± 22.0 vs. 70.5 ± 20.4 years; p < 0.001). Both, complication (21.9% vs. 9.9%; p < 0.001) and mortality (8.0% vs. 1.9%; p < 0.001) rates, were significantly higher.

In the subgroup of acetabular fractures, the operation time was significantly longer in the group with the combined injury (198 ± 104 vs. 176 ± 81 min, p = 0.001). The grade of successful anatomic reduction of the acetabular fracture did not differ between the two groups.

Conclusion

Patients with a pelvic injury have a concomitant abdominal trauma in about 20% of the cases. The clinical course is significantly prolonged in patients with a combined injury, with increased rates of morbidity and mortality. However, the quality of the reduction in the subgroup of acetabular fractures is not influenced by a concomitant abdominal injury.

Trial registration

ClinicalTrials.gov, NCT03952026, Registered 16 May 2019, retrospectively registered

Efficacy of an antigravity treadmill on functional outcome in non-operatively treated pelvic fractures: a prospective pilot study

Background/Aims

Treating pelvic fractures non-operatively is possible. The immobilisation stage of recovery requires different adjustment processes compared to those used in operative treatment. The aim of the present study was to prove the additional benefit an antigravity treadmill can have on patients with non-operatively treated pelvic fractures.

Methods

A prospective pilot study, including patients with non-operatively treated pelvic fractures as the intervention group and healthy volunteers as a control group, was undertaken. Patients of the intervention group participated in a training session with an antigravity treadmill every 3 days for a total of 40 days, in addition to physiotherapy, lymph drainage massage and manual therapy. Patients were evaluated using a dynamic gait index, and a numeric rating scale on three successive dates, to assess their pain. A standardised gait analysis was also carried out.

Results

The intervention group comprised 9 patients, while 33 patients made up the control group. All patients completed the protocols and experienced a significant decrease in pain and increase of mobility. Gait analysis showed that by the 40-day follow-up, patients in the intervention group had regained almost normal gait patterns when compared to the control group. At each time point, a significant improvement in patients' gait patterns could be seen.

Conclusions

The results concurred with previous studies, suggesting that the antigravity treadmill is safe and that recovery to almost normal gait patterns is possible, while the comparison to a healthy group strengthened the data. The present prospective study thus showed promising results regarding the efficacy of the antigravity treadmill, despite study limitations.

Technical limitations of REBOA in a patient with exsanguinating pelvic crush trauma: a case report

Background

Resuscitative endovascular balloon occlusion of the aorta (REBOA) is an effective adjunct in hemodynamic unstable patients with uncontrolled and non-compressible torso hemorrhage promoting temporary stability during injury repair. The aim of our study was to analyze real life usability of REBOA based on a case report and to review the literature with respect to its possibilities and limitations.

Case presentation

We present the case of a 17-years old female patient who sustained a severe roll-over trauma and pelvic crush injury as a bicyclist by a truck. Upon arrival of the first responders, the patient was awake, alert, and following commands.Subsequent to lifting the truck, the patient became hypotensive and required cardiopulmonary resuscitation, application of a pelvic binder, and endotracheal intubation at the accident scene. She was then admitted by ambulance to our trauma center under ongoing resuscitative measures. After primary survey, it was decided to perform a REBOA with surgical approach to the left femoral artery. Initial insertion of the catheter was successful but could not be advanced beyond the inguinal region. Hence, the patient was transferred to the operating room (OR) but died despite maximum therapy. In the OR and later autopsy, we found a long-distance ruptured and dehiscent external iliac artery with massive bleeding into the pelvis in the context of a bilateral vertical shear fractured pelvic bone.

Conclusion

REBOA can be a useful adjunct but there is a major limitation with potential vascular injury after pelvic trauma. In these situations, cross-clamping the proximal aorta or pre-peritoneal pelvic packing as "traditional" approaches of hemorrhage control during resuscitation may be the most considerable methods for temporary stabilization in severely injured trauma patients. More clinical and cadaveric studies are needed to further understand indications and limitations of REBOA after severe pelvic trauma.

Fragility Fractures of the Pelvis Classification: A Multicenter Assessment of the Intra-Rater and Inter-Rater Reliabilities and Percentage of Agreement

BACKGROUND

The fragility fractures of the pelvis (FFP) classification was established to address the specific fracture morphology and dynamic instability in the elderly. Although this system is frequently used, data on the intra-rater and inter-rater reliabilities are lacking.

METHODS

Six experienced and 6 inexperienced surgeons and 1 surgeon trained by the originator of the FFP classification ("gold standard") each used the FFP classification 3 times to grade the computed tomography (CT) scans of 60 patients from 6 hospitals. We assessed intra-rater and inter-rater reliabilities using Fleiss kappa statistics and the percentage of agreement using the "gold standard," the submitting hospital, and the majority vote as references.

RESULTS

The intra-rater reliability for the FFP classification was mainly moderate, with a mean Fleiss kappa coefficient (and 95% confidence interval) of 0.46 (0.40 to 0.50) for the complete classification (i.e., both the main-group FFP ratings [I through III] and the subgroup ratings [a, b, and c]) and 0.60 (0.53 to 0.65) for the main group only. The inter-rater reliability was substantial for the main group classification (0.61 [0.54 to 0.66]) and moderate for the complete classification (0.53 [0.48 to 0.58]). The percentage of agreement was 68% to 80%. The lowest agreement was found for FFP II and III.

CONCLUSIONS

The FFP classification displayed moderate and substantial intra-rater and inter-rater reliabilities.

CLINICAL RELEVANCE

With moderate to substantial intra-rater and inter-rater reliabilities, the FFP classification forms a solid basis for future clinical investigations. The differentiation of FFP II from FFP III should be evaluated thoroughly, as the initial treatment changes from nonoperative for II to operative for III.

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

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

Effects of Cutting the Sacrospinous and Sacrotuberous Ligaments

The sacrospinous (SS) and sacrotuberous (ST) ligaments form a complex at the posterior pelvis, with an assumed role as functional stabilizers. Experimental and clinical research has yielded controversial results regarding their function, both proving and disproving their role as pelvic stabilizers. These findings have implications for strategies for treating pelvic injury and pain syndromes. The aim of the present simulation study was to assess the influence of altered ligament function on pelvis motion. A finite elements computer model was used. The two-leg stance was simulated, with the load of body weight applied via the fifth lumbar vertebra and both femora, allowing for nutation of the sacroiliac joint. The in-silico kinematics were validated with in-vitro experiments using the same scenario of load application following SS and ST transection in six human cadavers. Modeling of partial or complete ligament failure caused significant increases in pelvis motion. This effect was most pronounced if the SS and ST were affected with 164% and 182%, followed by the sacroiliac and iliolumbar ligaments with 123% and 147%, and the pubic ligaments with 113% and 119%, for partial and complete disruption, respectively. Simultaneous ligament transection multiplied the effects on pelvis motion by up to 490%. Unilateral ligament injury altered the motion at the pelvis contralaterally. The experiments presented here provide strong evidence for the stabilizing role of the SS and ST. A fortiori, the instability resulting from partial or complete SS and ST injury merits consideration in treatment strategies involving these ligaments as important stabilizers. Clin. Anat. 32:231-237, 2019. © 2018 Wiley Periodicals, Inc.

In-screw polymethylmethacrylate-augmented sacroiliac screw for the treatment of fragility fractures of the pelvis: a prospective, observational study with 1-year follow-up

BACKGROUND

The incidence of pelvic ring fractures in the elderly significantly increased. Because of persistent pain and immobilization associated with this injury, surgical treatment is recommended. To minimise comorbidities and surgical risk, percutaneous techniques are becoming more relevant. In-screw cement augmentation of sacroiliac screw fixation is a promising procedure; however, clinical follow-up data remain scarce. This study investigated the safety and possible complications of the procedure along with a 1-year follow-up.

METHODS

Thirty-four patients (treated with 43 screws) were prospectively included. Data on patients' age and sex, the mechanism of accident, fracture pattern, duration of hospital stay, surgery and adverse events were recorded. Data were obtained postoperatively on the reduction of pain and complications, such as infection, cement leakage and neurological deficits, and at 1-year follow-up on pain, quality of life according to the 12-Item Short Form Survey and mobility. Implant failure was defined as retraction or dislocation of screws and was also documented.

RESULTS

Screw-related complications occurred with 2 of 43 screws. None of these complications were related to cement augmentation. In-hospital adverse events occurred in 6 of 34 patients. Postoperative pain, measured by the visual analogue scale, was significantly reduced from 6.7 ± 1.4 preoperatively to 2.7 ± 1.0 postoperatively (p < 0.001). Although patients complained of pain at the 1-year follow-up, they reported a significant decline compared with pain at admission (3.4 ± 2.3; p < 0.001). Results on the quality of life were comparable with those for the age- and gender matched German population. All patients were mobile, and no implant failure was detected.

CONCLUSIONS

The results indicate that in-screw augmented sacroiliac screw fixation for fragility fractures of the pelvis is a safe technique. Pain was significantly reduced immediately after surgery compared to the preoperative state. Furthermore, significant pain reduction after one year compared to the preoperative state and quality of life was comparable to the age- and gender- matched German population. Thus, we recommend in-screw augmentation for screw fixation for sacral fragility fractures of the pelvis following failed conservative treatment.

[Additional emergency medical measures in trauma-associated cardiac arrest]

INTRODUCTION

More than half of all traumatic deaths happen in prehospital settings. Until now, there have been no long-term studies examining the actual additive treatment during trauma-associated cardiopulmonary resuscitation (tCPR), including pleural decompression, pericardiocentesis, tourniquets and external stabilization of the pelvis. The present cohort study evaluated forensic autopsy reports of trauma deaths occurring at the scene with respect to additive actions in preclinical tCPR as well as the potentially preventable nature of the individual death cases.

MATERIAL AND METHODS

All autopsy protocols from the Institutes of Legal Medicine in Leipzig and Chemnitz, Germany within the years 2011-2017 were retrospectively examined and all trauma deaths with professional prehospital tCPR at the scene, during transport or shortly after arriving at the emergency room were analyzed. In addition to epidemiological parameters all forms of medical procedure performed by emergency physicians and the injury patterns were recorded. Thus, the questions whether any of the trauma deaths were preventable and if failures in work-flow management were evident could be retrospectively answered through a structured Delphi method.

RESULTS

Overall, 3795 autopsy protocols were listed containing 154 trauma cases (4.1%) with various preclinical tCPR attempts (male patients 70.1%; mean age 48 ± 21 years). Most of them died at the accident site (84.4%), some during transport (2.6%) or directly after admission to a hospital (13.0%). Only 23 patients (14.9%) received 25 additional interventions exceeding the normal scope (pleural decompression 80.0%, pericardiocentesis 8.0% and external stabilization of the pelvis 12.0%). A relevant number of potentially reversible causes for trauma-associated cardiac arrest was determined. There were deficits in the performance of pleural decompression in cases of tension pneumothorax. Even if isolated traumatic hemopericardium was a rare occurrence in the examined cases, the rate of pericardiocentesis was still too low. Also, more focus needs to be placed on provisional external pelvic stabilization of trauma patients which was performed too rarely even though an instable pelvic ring was apparent during the postmortem external examination. None of the cases received a rescue thoracotomy even if a few patients might have derived benefit from this and none of the cases showed injury patterns with tourniquet indications. Furthermore, no single case of death due to incorrect or missing airway management was determined. Errors in work-flow management were found in 37.0% and potentially preventable deaths occurred cumulatively in 12.3% of the cases. The potentially preventable deaths were particularly related to penetrating chest injuries caused by a sharp force.

DISCUSSION

The percentage of patients who might benefit from additive treatment implemented in tCPR efforts was shown to be equal between the local situations in Leipzig and Chemnitz compared to previous reports in Berlin. A need for optimizing the professional resuscitation process still remains as not all reversible causes were appropriately addressed. Further training and education should intensively address the mentioned deficits and continuous awareness of necessary additional medical procedures in the preclinical setting in cases of traumatic cardiac arrest is inevitable. Cooperation with forensic institutes can help to impart particular issues and treatment options of emergency medicine in cases of potentially reversible causes of traumatic cardiac arrest.

Biomechanical analysis of stiffness and fracture displacement after using PMMA-augmented sacroiliac screw fixation for sacrum fractures

Cement augmentation of pedicle screws is the gold standard for the stabilization of osteoporotic fractures of the spine. In-screw cement augmentation, in which cement is injected through the cannula, is another option for fracture stabilization of fragility fractures of the sacrum. However, biomechanical superiority of this technique compared to conventional sacroiliac screw fixation has not been tested. The present study compares the stability of cement-augmented and non-cement-augmented sacroiliac screw fixation in osteoporotic sacrum fractures under cyclic loading. Eight human donor pelvises with intact ligaments and 5

Outcome and 2-Year Survival Rate in Elderly Patients With Lateral Compression Fractures of the Pelvis

Introduction:

Osteoporotic pelvic ring fractures are a rising problem for surgeons in industrialized countries. There is no evidence-based treatment strategy especially for lateral compression (LC) fractures involving the sacrum. The aim of this study was to evaluate and compare outcome and survival rate of nonoperative and operative treatment strategies for lateral compression fractures.

Patients and Methods:

In a retrospective study, 128 patients (aged ≥65 years) with an Orthopedic Trauma Association (OTA) types B2.1 and B3.3 fracture were included and analyzed regarding demographic and treatment data and adverse events. After a follow-up period of at least 2-year survival rate, quality of life and pain were evaluated using the EuroQol-5D and Short Form–12 questionnaires and the visual analog scale.

Results:

Fifty patients (78.3 ± 7.6 years) obtained operative treatment and 77 patients (82.7 ± 7.9 years) obtained nonoperative treatment. One died within 24 hours after admission. High rates of complications occurred in both groups (operative group: 18% and nonoperative group: 8%). Eighteen percent (14 of the 77) of conservatively treated patients needed operative treatment after discharge due to worsening pain and mobilization. The 2-year follow-up showed a high overall mortality (30%), with a significant higher survival rate for operatively treated patients (2-year survival: operatively treated 82% vs conservative 61%). No difference was found in pain and quality of life.

Discussion:

Elderly patients display a high rate and variety of complications and mortality in the aftermath of lateral compression fractures of the pelvis. Although a significantly higher 2-year survival rate for operatively treated patients was found, this study cannot give proof of superior position for operative treatment. Due to lacking data for alternative treatment algorithms especially for fracture-related immobilized patients, we recommended operative treatment with the aim to reduce complications related to prolonged bed rest and ensure early mobilization.

Lateral compression type B 2-1 pelvic ring fractures in young patients do not require surgery

PURPOSE

According to Young and Burgess, type B 2-1 pelvic fractures are a type of lateral compression fracture (LC-1) and are the most common pelvic injury at all ages. Although they are considered unstable in rotation and despite biomechanical recommendations for anterior stabilization, most authors recommend non-operative treatment. However, studies comparing outcomes and complications regarding operative versus non-operative treatment are still scarce.

METHODS

Seventy-one patients aged under 65 years with a type B 2-1 pelvic fracture were treated between 2006 and 2011. Patients in Group I (n = 35) were treated non-operatively and patients in Group II (n = 36) were treated operatively. Postoperative complications, clinical course, and follow-up (VAS for Pain, SF 36, EQ-5D) of at least 1 year postoperatively were evaluated.

RESULTS

Our data show that operatively treated patients had a significantly higher complication rate. Preoperatively, the only significant difference between the non-operative and operative groups was the amount of anterior fracture dislocation and the presence of an isolated pelvic ring fracture. In the postoperative follow-up, no significant differences were found regarding pain or quality of life.

CONCLUSION

Type B 2-1 pelvic ring fractures in young patients should be treated non-operatively.

Severe cardiac trauma or myocardial ischemia? Pitfalls of polytrauma treatment in patients with ST-elevation after blunt chest trauma

Introduction

Thoracic injuries are the third most common injuries in polytrauma patients. The mechanism of injury and the clinical presentation are crucially important for adequate emergency treatment.

Presentation of case

Here we present a case of a 37-year-old male who was admitted to our level-1 trauma center after motor vehicle accident. The emergency physician on scene presented the patient with a myocardial infarction. During initial clinical trauma assessment the patient developed circulatory insufficiency so that cardiopulmonary resuscitation was necessary. Considering the preclinical and clinical course it was decided to proceed with thrombolysis. Despite consistently sufficient resuscitation measures circulatory function was not restored and the patient remained in asystole and passed away.

Discussion

The initial assessment showed cardiopulmonary instability. After applying thrombolysis a therapeutic point of no return was reached because surgical intervention was impossible but autopsy findings showed severe myocardial and pulmonary contusions likely due to shear forces.

Conclusion

This case outlines the importance of understanding the key mechanism of injury and the importance of communication at each stage of healthcare transfer. A transesophageal echocardiography can help to identify injuries after myocardial contusion.

•

ECG changes after blunt chest trauma can be misleading.

•

Only by knowing the cause of accident can avoid erroneous time-intensive diagnostics and ensure a proper overall assessment.

•

A TEE can be a useful early adjunct in trauma management in the setting of ongoing instability because it can guide resuscitation efforts.

•

A stantardized preclinical – trauma room protocol according to ALTS^® should be used during transfer.

•

A thromblysis should be avoided in the acute setting because a blunt chest trauma can mimic a myocardial infarction.

[Polytrauma with pelvic fractures and severe thoracic trauma: does the timing of definitive pelvic fracture stabilization affect the clinical course?]

BACKGROUND

The aim of this study was to investigate the influence of the surgical timing in patients with pelvic fractures and severe chest trauma on the clinical course, especially on postoperative lung function.

METHODS

A total of 47 patients were included in a prospective dual observational study. The study investigated the clinical course depending on the time of operation based on the functional lung parameters, SAPS II, SOFA and total hospital stay.

RESULTS

The average ISS was 32±6, PTS was 34±11 and TTSS was 9±3 points. The pelvic fractures were stabilized definitively after an average of 7±2 days. The early stabilization correlated significantly with a lower TTSS and SAPS II on admission (p<0.05), shorter time of ventilation (p<0.05) and stay in the intensive care unit (p<0.01) as well as the decreased need for packed red blood cells (p<0.01).

CONCLUSIONS

In this study patients with pelvic fractures and thoracic trauma benefited positively from an earlier definitive pelvic fracture stabilization with respect to a shorter time of ventilation and stay in the intensive care unit due to a lower need for red cell concentrates.

Clinical implementation of finite element models in pelvic ring surgery for prediction of implant behavior: a case report

BACKGROUND

Osteosyntheses to stabilize pelvic-ring fractures were developed for younger patients, and are not universally indicated for elderly people. We present the results of parallel-arranged numerical simulations of fixation treatment that an elderly patient with a bagatelle-injured pelvic ring fracture received using a patient-specific finite element model.

METHODS

The clinical course of an osteosynthetic stabilized pelvic ring fracture, based on an actual case, was numerically simulated using a patient-specific finite element model.

FINDINGS

A previously validated finite element model of a human pelvis was customized with computed tomography data from a patient with a stabilized pelvic-ring fracture. Numerical simulation was used to analyze primary stability. The clinical process, represented by radiologic examinations, was compared with the results from the finite element simulation. Implant loosening as well as newly-occurring fractures were shown to coincide with regions with the highest stress levels.

INTERPRETATION

The results from the patient-specific finite element model closely resembled the actual clinical course especially in terms of the location of high strain concentration and subsequent implant loosening. This indicates that patient-specific finite element models have a potential to play an important role in planning osteosynthesis according to biomechanical stability.

[Influence of routine CT examination on fracture classification and therapy for pelvic ring fractures in patients aged over 65 years old]

BACKGROUND

The incidence of pelvic ring fractures in elderly patients increases continuously. Several studies showed that the complexity of injury is often underestimated and a fracture of the posterior pelvic ring not visible with conventional X-rays. The aim of this study was to determine the influence of routine CT on incidence, classification of and therapy for pelvic ring fractures in patients aged over 65 years.

PATIENTS AND METHODS

Between 2004 and 2010, 310 elderly patients with a pelvic ring fracture were admitted to a German university level 1 trauma centre. Patients of group 1 (2004-2006) were examined with CT only if a pelvic ring fracture was diagnosed by X-ray and pain in the posterior pelvic ring persisted so that mobilisation was impossible. In group 2 (2007-2010) CT was used for routine examination. Demographic data, injury mechanism and severity (ISS) were documented as well as time and type of diagnostic procedure. Also fracture classification (AO), time and type of treatment were investigated in correlation with total hospital stay.

RESULTS

252 (82 %) patients were female, the median age was 81 years (65-100 years). 228 (74 %) had a low energy trauma, 41 (13 %) a traffic accident and 12 (4 %) had fallen from heights over 3 m. Only in 29 (9 %) cases was no trauma evident. 35 (11 %) patients were injured with an ISS over 16 and classified as polytrauma. The mean ISS was 26.8 ± 11.7. In group 2 the incidence of type A fractures decreased from 64 % to 36 %, whereas the incidence of type B fractures increased from 25 % to 49 % as did isolated sacrum fractures from 1 % to 6 %. Also the indication for operative stabilisation changed in type B fractures from 33 % to 40 % and in isolated sacrum fractures to 71 %. Total hospital stay was between eight and ten days in non-operative and between 20 and 22 days in operative treatment.

CONCLUSION

A low energy trauma is the major cause of injury for patients of an age over 65 years with a pelvic ring fracture. With the routine CT examination type B fractures and isolated sacrum fractures are seen more often than expected and resulting in a change of treatment procedures.