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.

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.

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.

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.

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.

[U-shaped fractures of the sacrum-what is the correct treatment? : A presentation of three cases]. / U-Frakturen des Os sacrum ­ Wie therapiert man richtig? : Eine Präsentation dreier Fälle.

BACKGROUND: Sacral U­shaped fractures are rare but severe injuries. Due to the resulting spinopelvic dissociation they are highly unstable. Reduction and stabilization are usually required and decompression may be necessary due to frequent concomitant neurological injuries. In the literature there is no consensus with respect to the selection of the surgical approach. CASE PRESENTATIONS: After a road traffic accident an 18-year-old woman suffered a U-fracture of the sacrum type II according to Roy-Camille and was treated with bilateral double sacroiliac screw osteosynthesis and sacral laminectomy. A 76-year-old man with a U­fracture type I according to Roy-Camille after falling down the stairs was treated by lumbopelvic fixation. A 24-year-old man with U­fracture type II according to Roy Camille after a road accident was treated with triangular vertebropelvic stabilization and sacral laminectomy. For all patients the outcome was good. CONCLUSION: Surgical treatment is necessary, with minimally invasive techniques offering advantages over open surgery. A distinction must be made between lumbopelvic fixation and posterior pelvic ring fixation. Multiple aspects must be taken into consideration of the indications when selecting the surgical technique.

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.

Age and "general health"-beside fracture classification-affect the therapeutic decision for geriatric pelvic ring fractures: a German pelvic injury register study.

PURPOSE: Pelvic ring fractures in the elderly gain increasing importance. Nonetheless, data on factors influencing treatment decision in relation to fracture classification, age, and the resulting treatment are still rare. METHODS: Prospectively collected data of the German Pelvic Injury Registry from patients aged over 65 years with a pelvic ring fracture were evaluated retrospectively. Acetabular fractures, as well as type A1 and A3 fractures, were excluded. The variables age, injury pattern, type of treatment, the reason for conservative treatment, and Orthopaedic Trauma Association (OTA)/Tile classification were analyzed. Furthermore, the fracture distribution was examined after dividing patients into six age groups. RESULTS: A total of 1814 patients with a mean age of 80.7 ± 7.6 years, predominantly female (79.0%), were available for evaluation. The majority of patients suffered from isolated pelvic ring fractures (70.1%) and 8.2% were severely injured (ISS > 16). The most common fracture types were type A2 (35.4%), type B2 (38.0%), and type C1 (7.3%). Especially pelvic ring fractures of type A2 (96.9%) and type B2 (83.0%) were treated conservatively (overall 76.9%). Fracture instability according to the OTA/Tile classification increased the probability for an operative treatment (generalized odds ratio [OR] 6.90 [5.62; 8.52]). In contrary, increasing age independent of the fracture pattern decreased this probability (OR 0.47 [0.41-0.53]). With increasing fracture instability, general health conditions were up to 50% of the reasons for conservative treatment. CONCLUSION: The results of the present study underline the importance of the factors age and general health besides fracture classification for therapeutic decision-making in the treatment of pelvic ring fractures in the elderly.

Femoral neck fractures in old age treated with hemiarthroplasty : Effects of preoperative waiting time and timing of surgery on the risk of periprosthetic infections.

BACKGROUND: Hemiarthroplasty is an established treatment for femoral neck fractures (FNF) in old age; however, approximately 20-30% of patients die within 1 year after surgery. Periprosthetic joint infections (PJI) are one of the severest complications and associated with a high mortality rate. In this retrospective study of aged patients with FNF treated with hemiarthroplasty, the incidence of PJI was evaluated with respect to the influence of the delay to and timing of surgical treatment. PATIENTS AND METHODS: The data of patients suffering from FNF and admitted to this hospital between January 2012 and December 2014 were evaluated. Demographic data, timing of surgery, intraoperative complications, PJI and other general complications, hospitalization time and mortality were recorded. RESULTS: In this study 178 patients were included in the follow-up (114 women and 64 men). The median age of the patients was 83 years (range 55-105 years). The rate of PJI was 3.9% (7/178) and mortality was 5.6% (10/178). Patients with PJI after hemiarthroplasty had a significantly longer hospital stay (17 vs. 10 days, p < 0.001) and a higher mortality (28% vs. 4.7%). No significant differences were found between the groups with respect to the time from admission to surgery. CONCLUSION: The occurrence of PJI after hip joint fractures treated with hemiarthroplasty in aged patients is associated with a significant increase in mortality. Risk factors include a longer surgery time, diabetes, intraoperative complications, postoperative bleeding and wound healing disorders. Surgical treatment within the first 24 h should be aimed for but not at the expense of adequate patient preparation or neglecting the patient's individual risk factors.

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.

Ligament-induced sacral fractures of the pelvis are possible.

Pelvic ring stability is maintained passively by both the osseous and the ligamentous apparatus. Therapeutic approaches focus mainly on fracture patterns, so ligaments are often neglected. When they rupture along with the bone after pelvic ring fractures, disrupting stability, ligaments need to be considered during reconstruction and rehabilitation. Our aim was to determine the influence of ligaments on open-book injury using two experimental models with body donors. Mechanisms of bone avulsion related to open-book injury were investigated. Open-book injuries were induced in human pelves and subsequently investigated by anatomical dissection and endoscopy. The findings were compared to CT and MRI scans of open-book injuries. Relevant structures were further analyzed using plastinated cross-sections of the posterior pelvic ring. A fragment of the distal sacrum was observed, related to open-book injury. Two ligaments were found to be responsible for this avulsion phenomenon: the caudal portion of the anterior sacroiliac ligament and another ligament running along the ventral surface of the third sacral vertebra. The sacral fragment remained attached to the coxal bone by this second ligament after open-book injury. These results were validated using plastination and the structures were identified. Pelvic ligaments are probably involved in sacral avulsion caused by lateral traction. Therefore, ligaments should to be taken into account in diagnosis of open-book injury and subsequent therapy.

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.

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.

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.

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.

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.

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.

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.