The clinical relevance of fixation failure after pubic symphysis plating for anterior pelvic ring injuries: an observational cohort study with long-term follow-up.

BACKGROUND: Open reduction and plate fixation is a standard procedure for treating traumatic symphyseal disruptions, but has a high incidence of implant failure. Several studies have attempted to identify predictors for implant failure and discussed its impact on functional outcome presenting conflicting results. Therefore, this study aimed to identify predictors of implant failure and to investigate the impact of implant failure on pain and functional outcome. METHODS: In a single-center, retrospective, observational non-controlled cohort study in a level-1 trauma center from January 1, 2006, to December 31, 2017, 42 patients with a plate fixation of a traumatic symphyseal disruption aged ≥ 18 years with a minimum follow-up of 12 months were included. The following parameters were examined in terms of effect on occurrence of implant failure: age, body mass index (BMI), injury severity score (ISS), polytrauma, time to definitive treatment, postoperative weight-bearing, the occurrence of a surgical site infection, fracture severity, type of posterior injury, anterior and posterior fixation. A total of 25/42 patients consented to attend the follow- up examination, where pain was assessed using the Numerical Rating Scale and functional outcome using the Majeed Pelvic Score. RESULTS: Sixteen patients had an anterior implant failure (16/42; 37%). None of the parameters studied were predictive for implant failure. The median follow-up time was six years and 8/25 patients had implant failure. There was no difference in the Numerical Rating Scale, but the work-adjusted Majeed Pelvic Score showed a better outcome for patients with implant failure. CONCLUSION: implant failure after symphyseal disruptions is not predictable, but appears to be clinically irrelevant. Therefore, an additional sacroiliac screw to prevent implant failure should be critically discussed and plate removal should be avoided in asymptomatic patients.

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.

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.

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.

Comparison of Percutaneous Screw Fixation to Open Reduction and Internal Fixation in Acetabular Fractures: A Matched Pair Study Regarding the Short-Term Rate of Conversion to Total Hip Arthroplasty and Functional Outcomes.

Closed reduction and percutaneous internal fixation (CRPIF) for acetabular fractures was introduced as a less invasive alternative to open reduction and internal fixation (ORIF) for moderately displaced fractures. Currently, comparisons of ORIF and CRPIF outcomes are rare. Twenty-three patients treated with CRPIF were matched with patients treated with ORIF based on sex, age, and fracture classification. Surgery-dependent and -independent factors of the in-hospital stay, the conversion rate to total hip arthroplasty (THA), and quality of life were assessed. The ORIF group had a higher preoperative fracture step (p = 0.04) and gull wing sign (p = 0.003) compared with the CRPIF group. Postoperatively, the gap and step size were not significantly different between the groups (p > 0.05). CRPIF required less time (p < 0.0001) and transfusions (p = 0.009) and showed fewer complications (p = 0.0287). Four patients were converted to THA (CRPIF, n = 1; ORIF, n = 3; p = 0.155) because of posttraumatic osteoarthritis. Functional outcomes and pain were similar in both groups (p > 0.05). The present study revealed less blood loss and a lesser extent of reduction in patients treated with CRPIF than in those treated with ORIF. The rates of conversion to THA and functional outcomes did not differ between CRPIF and ORIF. CRPIF appeared to be a valuable treatment option for selected patients.

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.

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.

Risk factors for intraoperative greater trochanteric fractures in hemiarthroplasty for intracapsular femoral neck fractures.

PURPOSE: Hemiarthroplasty is widely accepted as the treatment of choice in elderly patients with a displaced intracapsular femoral neck fracture. Intraoperative greater trochanteric fractures thwart this successful procedure, resulting in prolonged recovery, inferior outcome, and increased risk of revision surgery. Hence, this study analyzed factors potentially associated with an increased risk for intraoperative greater trochanteric fracture. METHODS: This retrospective study included 512 hemiarthroplasties in 496 patients with a geriatric intracapsular femoral neck fracture from July 2010 to March 2020. All patients received the same implant type of which 90.4% were cemented and 9.6% non-cemented. Intra- and postoperative radiographs and reports were reviewed and particularly screened for greater trochanteric fractures. RESULTS: Female patients accounted for 74% and mean age of the patients was 82.3 (± 8.7) years. 34 (6.6%) intraoperative greater trochanteric fractures were identified. In relation to patient-specific factors, only a shorter prothrombin time was found to be significantly associated with increased risk of intraoperative greater trochanteric fracture (median 96%, IQR 82-106% vs. median 86.5%, IQR 68.8-101.5%; p = 0.046). Other factors associated with greater trochanteric fracture were a shorter preoperative waiting time and changes in perioperative settings. Outcome of patients with greater trochanteric fracture was worse with significantly more surgical site infection requiring revision surgery (17.6% vs. 4.2%, p = 0.005). CONCLUSION: Prolonged prothrombin time, a shorter preoperative waiting time, and implementing new procedural standards and surgeons may be associated with an increased risk of a greater trochanteric fracture. Addressing these risk factors may reduce early periprosthetic infection which is strongly related to greater trochanteric fractures.

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.

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.

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.

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.

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.

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.