Beckenringfrakturen im Alter: Die unterschätzte osteoporotische Fraktur

Short-term mobility in low-energy pelvic ring fractures after conservative treatment

BACKGROUND

The growing population of elderly people is leading to a rising number of pelvic ring fractures. These often involve combinations of pubic branch and sacrum fractures, as seen in lateral compression type 1 (LC1) and 2 (LC2) fractures or more precisely classified as fragility fractures of the pelvis (FFP). The combined impact on the anterior and posterior ring brings the risk of prolonged pain, resulting in decreased mobility and increased complications. Given the higher multimorbidity of this population, surgical treatment poses a greater risk of intra- and post-operative complications. Hence, the management and treatment of this particular type of fracture remain challenging.

METHODS

A retrospective data analysis of 41 patients (F/M; 27/14) treated conservatively for low-energy LC1 or LC2 fractures was performed between 2017 and 2020. The fractures were classified using Rommens' FFP classification. The primary outcome was mobility at 2 and 6 weeks, assessed through chart analysis and phone interviews. To determine factors influencing patient outcomes fracture consolidation was assessed via X-ray analysis. As a secondary outcome logistic regression and decision tree analyzes were conducted.

RESULTS

The mean age at the time of fracture was 79.8 ± 12.5 (SD) years. Thirty-two patients regained mobility (F/M; 25/7) after 2 weeks. Another 7 patients were mobile after 6 weeks (F/M; 2/5). Two male patients did not regain mobility. Male sex emerged as the sole independent predictor of non-mobility at 2 weeks (p = 0.0037). Age, BMI, pubic branch fracture dislocation >5 mm, analgesic use of opiates, corticosteroid therapy, alcohol and smoking showed no association with mobility recovery. Fracture consolidation was observed in 73.2 % of patients (F/M; 21/9), while one female had no consolidation. Ten patients (F/M; 5/5) were lost to follow-up.

CONCLUSIONS

Our study shows that LC1 (FFP IIb, IIc) and LC2 (FFP IIIc, IVb) fractures can be effectively treated conservatively, with successful remobilization within 6 weeks. The only independent negative predictor of early mobilization was male sex. Pubic branch displacement >5 mm did not affect the outcome. Therefore, conservative management proves to be a viable option for low-energy LC1 or LC2 fractures.

LEVEL OF EVIDENCE

IV (retrospective study).

Lumbopelvic Stabilization with Two Methods of Triangular Osteosynthesis: A Biomechanical Study

(1) Background: Pelvic fractures, and particularly instabilities of the dorsal pelvic ring, are becoming increasingly prevalent, particularly in orthogeriatric patients. Spino-pelvic triangular osteosynthesis is an effective approach to achieve sufficient stabilization in vertically unstable fractures. This study compares two types of osteosynthesis: the conventional one and a novel instrumentation where the iliosacral screw is placed through a fenestrated iliac screw. (2) Methods: Sixteen artificial osteoporotic L5+pelvis models with an unstable sacral fracture have been instrumented with either an iliac screw connected with a rod to a L5 pedicle screw and an iliosacral screw (TF) or a fenestrated ilium screw connected with a rod to a L5 pedicle screw and an iliosacral screw passing through the fenestra of the iliac screw (TFS). Biomechanical testing was performed using cyclic loading until failure. (3) Results: Both configurations yielded comparable results with regard to initial stiffness, implant loosening, and cycles to failure. The TFS exhibited markedly higher values for cycles to failure and markedly lower values for loosening. However, due to the characteristics of the artificial bone model, these findings were not significant. (4) Conclusions: The novel triangular fixation systems demonstrated comparable results to the standard triangular osteosynthesis configuration.

[Conservative fracture treatment in old people]

The numbers of osteoporotic fractures will increase due to the demographic change, which particularly affects the proximal femur, pelvis, proximal humerus, wrist and vertebral column. Surgical treatment is superior to conservative treatment of proximal femoral fractures. Non-dislocated fractures of the wrist can also be treated with a plaster cast but studies suggest that the results in the first 12 months are better after surgical treatment. The situation is similar for fractures of the proximal humerus and non-dislocated fractures in particular can also be treated conservatively. A score and classification were recently developed for making decisions on the treatment of osteoporotic vertebral fractures. Fractures of the anterior and posterior pelvic ring can be treated conservatively with the patient under sufficient analgesia as long as there is no substantial dislocation. The highest priority in geriatric traumatology is fast remobilization.

Standard imaging in the emergency department in geriatric patients with immobilizing pelvic pain after low-energy trauma or without trauma: X-ray vs. computed tomography

PURPOSE

Geriatric pelvic ring injuries, evaluated solely by X-ray, are often misclassified or even missed. This can result in prolonged immobilization and persistent pelvic pain. The aim of this study was to assess the sensitivity and specificity of X-ray imaging in patients aged ≥ 70 years with immobilizing pelvic pain.

METHODS

107 geriatric patients (23 males, 84 females) with immobilizing pain after traumatic or atraumatic causes were included in this retrospective study. 91 patients had an anteroposterior (AP) X-ray of the pelvis and after that a computed tomography (CT) of the pelvis. All patients were treated in a level 1 trauma center from December 2018 to September 2020. The mean age was 83.07 ± 6.08 years.

RESULTS

The overall evaluation of the diagnostic performance of AP Pelvic X-ray imaging in the study population compared to the CT pelvis ("gold standard") resulted in a sensitivity of (2.7 %) and a specificity of (94.4 %). Specific for pelvic ring fractures in the study population there was a sensitivity of (3.4 %) and a specificity of (94.4 %).

CONCLUSION

The results highlights issues with the AP Pelvic X-ray as the diagnostic tool of choice in this study population, confirming the findings of previous studies on the underestimated problem of osteoporotic pelvic ring fractures in geriatric patients. This again confirms the need for a new optimized diagnostic algorithm, which takes into account the differences of the orthogeriatric patient cohort.

Stabilization of Traumatic Iliosacral Instability Using Innovative Implants: A Biomechanical Comparison

(1) Background: Demographic changes over the past decade have had a significant impact on pelvic ring fractures. They have increased dramatically in the orthogeriatric population. Surgeons are faced with implant fixation issues in the treatment of these fragility fractures. This study compares two innovative implants for stabilizing the iliosacral joint in a biomechanical setting. (2) Methods: An iliosacral screw with a preassembled plate allowing the placement of an additional short, angular stable screw in the ilium and a triangular fixation system consisting of a fenestrated ilium screw and an iliosacral screw quasi-statically inserted through the "fenestra" were instrumented in osteoporotic artificial bone models with a simulated Denis zone 1 fracture. Biomechanical testing was performed on a servo-hydraulic testing machine using increasing, synchronous axial and torsional sinusoidal cyclic loading to failure. (3) Results: The SI-Plate and TriFix showed comparable stiffness values. The values for fracture gap angle and screw tip cutout were significantly lower for the TriFix compared to the SI-Plate. In addition, the number of cycles to failure was significantly higher for the TriFix. (4) Conclusions: Implant anchorage and primary stability can be improved in iliosacral instability using the triangular stabilization system.

Sacroiliac versus transiliac-transsacral screw osteosynthesis in osteoporotic pelvic fractures: a biomechanical comparison

INTRODUCTION

Pelvic fractures were often associated with high-energy trauma in young patients, but data show a significant increase in osteoporotic pelvic fractures in old age due to the progressive demographic change. There is an ongoing discussion about the best fixation techniques, which are ranging from lumbopelvic fixation to sacral bars or long transiliac-transsacral (TITS) screws. This study analyzes TITS screw osteosynthesis and sacroiliac screw osteosynthesis (SI), according to biomechanical criteria of fracture stability in osteoporotic human pelvic cadavers ex vivo.

METHODS

Ten osteoporotic cadaveric pelvises were randomized into two groups of 5 pelvises each. An FFP-IIc fracture was initially placed unilaterally and subsequently surgically treated with a navigated SI screw or a TITS screw. The fractured side was loaded in a one-leg stance test setup until failure. Interfragmentary movements were assessed by means of optical motion tracking.

RESULTS

No significant difference in axial stiffness were found between the SI and the TITS screws (21.2 ± 4.9 N and 18.4 ± 4.1 N, p = 0.662). However, there was a significantly higher stability of the fracture treatment in the cohort with TITS-screws for gap angle, flexion, vertical movement and overall stability. The most significant difference in the cycle interval was between 6.000 and 10.000 for the gap angle (1.62 ± 0.25° versus 4.60 ± 0.65°, p = 0.0001), for flexion (4.15 ± 0.39 mm versus 7.60 ± 0.81 mm, p = 0.0016), interval 11.000-15.000 for vertical shear movement (7.34 ± 0.51 mm versus 13.99 ± 0.97 mm, p < 0.0001) and total displacement (8.28 ± 0.66 mm versus 15.53 ± 1.07 mm, p < 0.0001) for the TITS and the SI screws.

CONCLUSIONS

The results of this biomechanical study suggest a clear trend towards greater fracture stability of the TITS screw with significantly reduced interfragmentary movement. The application of a TITS screw for the treatment of the osteoporotic pelvic ring fracture may be prioritized to ensure the best possible patient care.

Cerclage augmentation of S1-S2 transsacral screw fixation in osteoporotic posterior pelvis ring injuries: A biomechanical feasibility study

Injuries of the posterior pelvic ring are predominantly associated with osteoporosis. Percutaneously placed screws transfixing the sacroiliac joint have become the gold standard for their treatment. However, screw cut-out, backing-out, and loosening are common complications. One promising option could be cerclage reinforcement of cannulated screw fixations. Therefore, the aim of this study was to evaluate the biomechanical feasibility of posterior pelvic ring injuries fixed with S1 and S2 transsacral screws augmented with cerclage. Twenty-four composite osteoporotic pelvises with posterior sacroiliac joint dislocation were stratified into four groups for S1-S2 transsacral fixation using either (1) fully threaded screws, (2) fully threaded screws with cable cerclage, (3) fully threaded screws with wire cerclage, or (4) partially threaded screws with wire cerclage. All specimens were biomechanically tested under progressively increasing cyclic loading until failure. Intersegmental movements were monitored by motion tracking. The transsacral partially threaded screw fixation with wire cerclage augmentation resulted in significantly less combined angular intersegmental movement in the transverse and coronal plane versus its fully threaded counterpart (p = 0.032), as well as in significantly less flexion versus all other fixations (p ≤ 0.029). Additional cerclage augmentation could be performed intraoperatively to improve the stability of posterior pelvic ring injuries treated with S1-S2 transsacral screw fixation. Further investigations should follow to consolidate the current results on real bones and possibly consider execution of a clinical study.

[Sacral H-shaped fractures between traumatic, insufficiency and fatigue fractures : Similarities, differences and controversies]

In the basic entirety of stress fractures, insufficiency fractures are defined as fractures caused by prolonged normal or physiological loading of a bone with insufficient elastic resistance. This clearly distinguishes it from fatigue fractures, in which excessive loads are continuously applied to a bone with normal elastic resistance. According to Pentecost (1964) both entities of stress fracture result from "the inherent inability of the bone to withstand stress applied without violence in a rhythmical, repeated, subthreshold manner". This distinguishes them from acute traumatic fractures. In the clinical routine these differences are not always so clearly presented. The example of the H‑shaped sacral fracture is used to illustrate the relevance of a clear terminology. In this context, current controversies in the treatment of sacral insufficiency fractures are discussed.

Posterior pelvic ring involvement detected with CT taken within a week of admission in acute fragility fractures of the pelvis (FFP) does not predict failure of conservative treatment: a retrospective cohort study

BACKGROUND

Acute low energy pubic rami fractures in the elderly receive primarily conservative treatment. There is debate to what extent posterior ring involvement, which is detected superiorly by CT compared to X-ray, has an impact on outcome and may require modified treatment. We want to demonstrate if posterior ring involvement has an influence on different types of outcome in primarily conservatively treated acute FFP, questioning the usefulness of early CT. Additionally we analysed the early fracture pattern in cases where conservative treatment failed with need for secondary surgery.

METHODS

A retrospective cohort study of 155 consecutive patients, recruited between 2009 and 2016, aged over 65 years diagnosed with an acute LE-PFr on X-ray at the emergency department of a single, level-one trauma centre and receiving an early CT. A set of outcome parameters was compared between patients with an isolated pubic rami fracture (CTia) and patients who had a combined posterior pelvic ring fracture (CTcp).

RESULTS

There were 155 patients of whom 85.2% were female with a mean age of 83 years. 76.8% of patients living at home returned home and 15.5% moved to a nursing home. Mortality rate during hospitalisation was 6.4% and 14.8% at one year post-trauma. Secondary fracture displacement occurred in 22.6%. Secondary surgery was performed in 6 cases (3.9%). Median hospitalisation length of stay was 21 days (range 0 to 112 days). There was no significant association between the subgroups and change in residential status (p = 0.65), complications during hospitalisation (p = 0.75), mortality rate during admission (p = 0.75) and at 1 year (p = 0.88), readmission within 30 days (p = 0.46) and need for secondary surgery (p = 0.2). There was a significant increased median length of stay (p = 0.011) and rate of secondary displacement (p = 0.015) in subgroup CTcp. Secondary displacement had no impact on in-hospital complications (p = 0.7) nor mortality rate during admission (p = 0.79) or at 1 year (0.77). Early CT in patients who underwent secondary surgery showed stable B2.1 lesions in 4 of 6 cases.

CONCLUSIONS

Our data suggest that early CT in patients with conservatively treated acute LE-PFr in order to detect posterior lesions, has limited value in predicting failure of conservative treatment.

Influence of the Backward Fall Technique on the Transverse Linear Acceleration of the Head during the Fall

BACKGROUND

The formation of large accelerations on the head and cervical spine during a backward fall is particularly dangerous due to the possibility of affecting the central nervous system (CNS). It may eventually lead to serious injuries and even death. This research aimed to determine the effect of the backward fall technique on the linear acceleration of the head in the transverse plane in students practicing various sports disciplines.

METHODS

The study involved 41 students divided into two study groups. Group A consisted of 19 martial arts practitioners who, during the study, performed falls using the side aligning of the body technique. Group B consisted of 22 handball players who, during the study, performed falls using the technique performed in a way similar to a gymnastic backward roll. A rotating training simulator (RTS) was used to force falls, and a Wiva^® Science apparatus was used to assess acceleration.

RESULTS

The greatest differences in backward fall acceleration were found between the groups during the buttocks' contact with the ground. Larger changes in head acceleration were noted in group B.

CONCLUSIONS

The lower changes in head acceleration obtained in physical education students falling with a lateral body position compared to students training handball indicate their lower susceptibility to head, cervical spine, and pelvis injuries when falling backwards as caused by horizontal force.

Percutaneous sacroiliac screw fixation in fragility fractures of the pelvis: Comparison of two different augmentation techniques

OBJECTIVE

Fragility fractures of the pelvis (FFP) are becoming increasingly common. Percutaneous sacroiliac screw fixation is an accepted and safe treatment method for FFP. Augmentation is an option to optimize fixation strength of the screws. This study aims to compare patient mobility and the occurrence of complications after operative treatment of FFP utilizing two different augmentation techniques.

METHODS

All patients who received augmented sacroiliac screws for the treatment of FFPs between 01.01.2017 and 31.12.2018 at one of the two participating hospitals were included. The operative techniques only differed with regards to the augmentation method used. At the one hospital cannulated screws were used. Definitive screw placement followed augmentation. At the other hospital cannulated and fenestrated screws were used, permitting definitive screw placement prior to augmentation.

RESULTS

In total, 59 patients were included. The NRS score for pain was significantly lower after surgery. Preoperative mobility levels could be maintained or improved in 2/3 of the patients. There were no fatal complications. Two revision surgeries were performed because of screw misplacement. There were no significant differences between the two augmentation techniques in terms of complications.

CONCLUSION

Both augmentation techniques have a low complication rate and are safe methods to maintain patients' mobility level. The authors advocate early consideration of surgical treatment for patients with FFP. Augmentation can be considered a safe addition when performing percutaneous sacroiliac screw fixation.

FRAGILITY FRACTURES OF THE SACRUM: A SILENT EPIDEMIC

Fragility fractures of the sacrum (FFS) are caused by low-energy trauma in the elderly population. Due to the nuanced symptomatology, many FFS remains unrecognized and the prevalence is underestimated. The clinical presentation varies, typically presenting with weightbearing low back pain without even remembering of a previous trauma. Radiographs are usually insufficient for the diagnosis and second level imaging modalities are required. In particular, magnetic resonance demonstrated the highest diagnostic accuracy. Treatment should aim to guarantee early mobilization and weightbearing, efficient pain relief and early discharge from the hospital to a proper facility for rehabilitation. Conservative treatment is reserved to non-displaced fractures with an adequate pain relief within one week allowing early mobilization. Otherwise, surgical treatment must be preferred. Nowadays, minimally invasive techniques, such as ileo-sacral screws or trans-sacral bar osteosynthesis, are safe and effective procedures and have overcome open procedures. In more complex patterns, with complete dissociation between the pelvic ring and the ilio-lumbar spine, spino-pelvic fixation is the procedure of choice.

Insufficiency Fractures vs. Low-Energy Pelvic Ring Fractures - Epidemiological, Diagnostic and Therapeutic Characteristics of Fragility Fractures of the Pelvic Ring

BACKGROUND

Fragility fractures of the pelvis (FFP) encompass two fracture entities: fracture after low-energy trauma and insufficiency fracture without trauma. It is unclear whether the two subgroups differ in terms of diagnosis and therapy. The aim of this retrospective study was to evaluate insufficiency fractures with regard to defined parameters and to compare specific parameters with the fractures after low-energy trauma.

PATIENTS AND METHODS

In the period from 2008 to 2017, 203 patients with FFP were recorded at our clinic (Level 1 Trauma Centre DGU, SAV approval). Of these, 25 had an insufficiency fracture and 178 had a pelvic ring fracture after low-energy trauma. Epidemiological, diagnostic and therapeutic parameters were examined.

RESULTS

There was a relative increase in the insufficiency fracture within the FFP (2008 - 2009: 5.0% vs. 2015 - 2017: 17.8%). In these patients, osteoporosis tended to be more pronounced than in patients after low-energy trauma (t-value: - 3.66 vs. - 3.13). The diagnosis of insufficiency fractures showed increased use of MRI and DECT (60.9% vs. 26.0%) and a high proportion of type IV fractures after FFP (40.0% vs. 7.9%). In terms of therapy, surgical treatment of the insufficiency fracture was sought more often (68,2% vs. 52,1%), with a tendency towards increased use of combined osteosynthesis procedures (14.3% vs. 7.6%).

CONCLUSION

We were able to show that as the number of cases increases, the insufficiency fracture becomes more important within FFP. If these patients tend to have more pronounced osteoporosis, particular attention should be paid to the diagnosis and adequate therapy of the osteoporosis, especially in the case of an insufficiency fracture. In addition to the increased diagnostic testing using MRI and DECT to detect oedema and the increased surgical therapy for this type of fracture, it is also noteworthy that the insufficiency fracture can cause higher-grade fractures after FFP.

Immediate full weight bearing after pelvic percutaneous fixation by screw for simple acetabular and pelvic ring fractures in patients older than sixty five years

PURPOSE

The aim of this study was to assess the walking and weight-bearing abilities of patients older than 65 years with a simple acetabular or pelvic ring fracture treated with pelvic percutaneous screwing (PPS).

METHODS

This study included 27 patients. This was a retrospective, single-centre observational study conducted in a level 1 trauma centre from September 2019 to April 2021. All patients older than 65 years who underwent PPS for an acetabular or pelvic ring fracture were included.

RESULTS

All patients were able to walk and bear weight at one day after PPS. The mean walking distance increased from 19.4 m the day after the operation to 59.8 m, 497.8 m, and 1402 m at discharge, three and six weeks after the operation, respectively. The average pain visual analog scale scores before and after the operation were 4.1 (range, 3.6-5.1; standard deviation [SD], 0.63) and 0.9 (range, 0.5-1.2; SD, 0.25), respectively (p < .0001). The average daily dose of paracetamol used before and after the operation was 2.2 (range, 1.7-3.1; SD, 0.59) g/d and 1.3 (range, 0.6-1.7; SD, 0.40) g/d, respectively (p = .0232). The average daily dose of morphine used before and after the operation was 5.7 (range, 4.7-6.7; SD, 0.76) mg/d and 1.6 (range, 0.5-2.9; SD, 1.09) mg/d, respectively (p = .0001).

CONCLUSION

All included patients were able to walk at four day after PPS. PPS was associated with reduced pain as well as a reduction in paracetamol and morphine use.

Sacroiliac Screw Placement with Ease: CT-Guided Pelvic Fracture Osteosynthesis in the Elderly

Background and Objectives: The number of geriatric patients presenting with fragility fractures of the pelvis is increasing due to ageing Western societies. There are nonoperative and several operative treatment approaches. Many of which cause prolonged hospitalisation, so patients become bedridden and lose mobility and independence. This retrospective study evaluates the postoperative outcome of a computed tomography-guided (CT-guided) minimally invasive approach of sacroiliac screw osteosynthesis. The particular focus is to demonstrate its ease of use, feasibility with the equipment of virtually every hospital and beneficial outcomes to the patients. Materials and Methods: 28 patients (3 men, 25 women, age 80.5 ± 6.54 years) with fragility fractures of the pelvis types II-IV presenting between August 2015 and September 2021 were retrospectively reviewed. The operation was performed using the CT of the radiology department for intraoperative visualization of screw placement. Patients only received screw osteosynthesis of the posterior pelvic ring and cannulated screws underwent cement augmentation. Outcomes measured included demographic data, fracture type, postoperative parameters and complications encountered. The quality of life (QoL) was assessed using the German version of the EQ-5D-3L. Results: The average operation time was 32.4 ± 9.6 min for the unilateral and 50.7 ± 17.4 for the bilateral procedure. There was no significant difference between surgeons operating (p = 0.12). The postoperative CT scans were used to evaluate the outcome and showed only one case of penetration (by 1 mm) of the ventral cortex, which did not require operative revision. No case of major complication was reported. Following surgery, patients were discharged after a median of 4 days (Interquartile range 3-7.5). 53.4% of the patients were discharged home or to rehabilitation. The average score on the visual analogue scale of the EQ-5D-3L evaluating the overall wellbeing was 55.6 (Interquartile range (IQR) 0-60). Conclusions: This study shows that the operative method is safe to use in daily practice, is readily available and causes few complications. It permits immediate postoperative mobilization and adequate pain control. Independence and good quality of life are preserved.

[Sacral fractures in geriatric patients]

Sacral fractures in geriatric patients are increasing and form a distinct entity. Clinical findings can be unspecific, which is why they are easily overlooked. It is mandatory to analyze the whole pelvic ring for evaluation of pelvic stability and for making treatment decisions. The primary diagnostics are made using plain X‑radiography; however, for assessment of the posterior pelvic ring an examination using sectional imaging is regularly necessary. The fragility fractures of the pelvis (FFP) classification is suitable as a guideline for the surgical treatment to be used. Stable fractures without relevant displacement after initial mobilization should be treated conservatively. Instability, failure of mobilization and persistent pain are, however, common reasons for surgical treatment. Fracture displacement determines if minimally invasive procedures for posterior and anterior pelvic ring stabilization are possible. Otherwise, complex open procedures such as spinopelvic fixation may be necessary.

Does augmentation increase the pull-out force of symphyseal screws? A biomechanical cadaver study

Purpose

Open reduction and internal fixation using anterior plate osteosynthesis currently represents the gold standard for the treatment of symphyseal disruptions. Since postoperative screw loosening with consequent implant failure is frequently observed, this study aims to evaluate if and to what extent augmentation can increase the pull-out force of symphyseal screws to improve the constructs stability.

Methods

Twelve human cadaveric anterior pelvic rings were separated at the symphyseal joint for bilateral testing, consequently achieving comparable sites. First, one non-augmented screw was drilled into the superior pubic ramus, whereas the contralateral side was primarily augmented. The screws were then withdrawn with a constant speed of 10 mm/min and the fixation strengths determined by the force (N) displacement (mm) curve. Finally, the primary non-augmented site was secondary augmented, representing revision surgery after initial implant failure, and the corresponding fixation strength was measured again.

Results

Augmentation compared to non-augmented screws displayed significantly higher pull-out forces with an increase in pull-out force by 377% for primary and 353% for secondary augmentation (p < 0.01). There was no significant difference in the pull-out force comparing primary and secondary augmentation (p = 0.74).

Conclusions

Primary and secondary augmentation significantly increases the stability of symphyseal screws and, therefore, potentially decreases rates of implant failure.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00068-022-01963-6.

Midterm follow-up of elderly patients with fragility fractures of the pelvis: A prospective cohort-study comparing operative and non-operative treatment according to a therapeutic algorithm

INTRODUCTION

The treatment of fragility fractures of the pelvis (FFP) is a challenge. The variations of non-operative- and of operative treatment are manifold and a structured treatment algorithm is lacking. The purpose of this study was to evaluate the outcome of elderly patients with a FFP who were treated with a therapeutic algorithm based on the FFP-classification.

PATIENTS AND METHODS

In a prospective cohort study 154 patients (mean age: 81.8 ±.61 (65-96); female: (86.8%; 131/154). BMI: 23.7 ±.34 (15-43)) with a FFP after inadequate mono trauma were treated according to a strict therapeutic algorithm between 04/2016 and 12/2018. According to a classification based on CT-scans either a standardized operative treatment or conservative therapy was induced and the outcome regarding objective measurements of mobility, pain, need for analgesics and mortality during hospital stay and after one year was analyzed.

RESULTS

82/154 participants (53.2%) were assigned to the conservative treatment group and 72 participants (46.8%) to the operative treatment group. The overall one-year survival rate was 78.1% (118/151). The survival of the operative treatment group was 90.7% (49/54) and significantly higher than the survival of the conservative treatment group (74.7%; 56/75; p=.023). The one-year follow up showed a high dispersion of the pain level in the operatively treated patients and a significantly higher mean in comparison to conservatively treated patients. Both treatment groups showed increasing numbers of patients with unlimited mobilization but also immobile patients. Overall in 31.0% (18/58) of the operative participants and in 14.9% (14/93) of the non-operatively treated participants complications occurred (p=.04).

CONCLUSION

The strict compliance to the presented treatment algorithm of FFP with an operative strategy starting from FFP IIc leads to a significantly lower mortality within one year in comparison to the conservatively treated patients. The worst outcome and the highest mortality was seen in patients who refused the recommendation of operative stabilization. The results of this study justify to proceed with the strict classification dependent treatment algorithm and also support the early switch-over to operative treatment of patients with failed conservative therapy in FFP I to FFP IIb.

Pull-out strength evaluation of cement augmented iliac screws in osteoporotic spino-pelvic fixation

INTRODUCTION

Spino-pelvic fixation has been widely accepted for surgical treatment of sacral tumor, scoliosis surgery and pelvic fractures. Cement augmentation of screws is an option to improve implant stability in osteoporotic bone quality. Aim of the present study is to compare iliac screw fixation without cement fixation and two cement application options in a biomechanical testing.

HYPOTHESIS

Cement augmentation of iliac screws leads to superior pull-out strength.

MATERIAL AND METHODS

Thirty female and osteoporotic human iliac bones were used. Three operation treatment groups were generated: Screw fixation (cannulated screws) without cement augmentation [Operation treatment (OT) A], screw fixation with cement augmentation before screw placement (cannulated screws) (OT B) and screw fixation with perforated screws and cement augmentation after screw placement (OTC). Pull-out tests were performed with a rate of 6mm/min. A load versus displacement curve was generated. Maximum pull-out force (N) was measured in the load-displacement curve.

RESULTS

Paired group 1 (OT A vs. OT B): Screw fixation without cement augmentation: 592.6N±335.07 and screw fixation with cement augmentation before screw placement: 996N±287.43 (p=0.0042). Paired group 2 (OT A vs. OT C): screw fixation without cement augmentation: 716.2N±385.86 and fenestrated screw fixation with cement augmentation after screw placement: 1324.88N±398.76 (p=0.0489). Paired group 3 (OT B vs. OT C): Screw fixation with cement augmentation before screw placement: 1077.2±486.66 and fenestrated screw fixation with cement augmentation after screw placement: 1298.2N±726.19 (p=0.3286).

DISCUSSION

Regarding iliac screw fixation for spino-pelvic ostesynthesis in osteoporotic bone, cement augmentation is significantly superior to solid iliac screw fixation respecting pull-out-strength. Nevertheless, further biomechanical studies are needed to verify these findings.

LEVEL OF EVIDENCE

Not applicable; biomechanical cadaver study.

The FFP-classification: From eminence to evidence

Fragility fractures of the pelvis (FFP) are a clinical entity with a rapidly growing incidence among elderly women. The characteristics of these fractures are different from those appearing after high-energy trauma. In 2013, the comprehensive FFP-classification provided a new framework for analysis of these fractures. It is based on the estimation of loss of stability in the pelvic ring. It is connected with recommendations for surgical treatment, justified by the fact that higher instabilities will need surgical stabilization. Since ist appearance, we can observe an increasing clinical-scientific interest in FFP. Multiple publications use the FFP-classification studying the characteristics of fractures, choice of treatment and outcome. Other studies focus on minimal-invasive techniques for stabilization. The actual knowledge describes higher mortality rates as the reference population, lower mortality rates after operative treatment but for the price of surgery-related complications. Mobility, independency and quality of life are worse than before the fracture, independent of the FFP-classification and the type of treatment. The classification triggered a rapid increase of expertise. This publication gives a detailed overview on the evolution from eminence to evidence.

Which factors influence treatment decision in fragility fractures of the pelvis? - results of a prospective study

BACKGROUND

The aim of the present study was to describe specific characteristics of patients suffering from pelvic fragility fractures and evaluate factors that might influence treatment decisions which may optimize treatment pathways and patient mobility in the future.

METHODS

A prospective study with patients suffering from fractures of the pelvis and aged 60 years or above was performed between 2012 and 2016. Data acquisition took place at admission, every day during hospitalization and at discharge.

RESULTS

One hundred thirty-four patients (mean age of 79.93 (± 7.67) years), predominantly female (84%), were included. Eighty-six patients were treated non-operatively. Forty-eight patients underwent a surgical procedure. The main fracture types were B2 fractures (52.24%) and FFP IIb fractures (39.55%). At the time of discharge, pain level (NRS) could be significantly reduced (p <  0.001). Patients who underwent a surgical procedure had a significantly higher pain level on day three and four compared to the non-operative group (p = 0.032 and p = 0.023, respectively). Significant differences were found in the mobility level: patients treated operatively on day four or later were not able to stand or walk on day three as compared to non-operatively treated patients. Regarding B2 fractures, a significantly higher mobility level difference between time of admission and discharge was found in patients treated with a surgical procedure compared to patients treated non-operatively (p = 0.035).

CONCLUSIONS

Fracture type, mobility level and pain level influence the decision to proceed with surgical treatment. Especially patients suffering from B2 fractures benefitted in terms of mobility level at discharge when treated operatively.

LEVEL OF EVIDENCE

II.

[Reliability of the FFP classification in pelvic fractures]

BACKGROUND

Pelvic fractures are typical for frail geriatric patients. They are characterized by increasing pain and loss of mobility. As geriatric pelvic fractures differ from the typical high velocity injuries, Rommens and Hofmann recommended a new classification for fragility fractures of the pelvis (FFP) in 2013. In addition to the location of the fracture they also assessed the degree of dislocation.

OBJECTIVE

Compared to known fracture classifications of the pelvis, the FFP classification appears complex. Therefore, this study was designed to investigate the interobserver reliability of the FFP classification.

MATERIAL AND METHODS

The members of the Section of Geriatric Traumatology (DGOU) were presented with 10 DICOM data sets with fractures of the pelvis for classification. As a reference the classification of P.M. Rommens, the author of the FFP, was established.

RESULTS

In this study 24 consultants (47%) and 27 (53%) residents took part. Also, six radiologists were invited to participate. A total of 493 assessments were made. In 184 (37%) cases there was agreement with the reference, in 183 (37%) computed tomography images the fractures were classified lower, in 26 (26%) higher than the reference. This initially resulted in a Cohens κ coefficient of 0.36. This corresponds to a sufficient agreement (fair) according to Garbuz. With the reduction of the classification to four main groups, the Cohens κ coefficient increased to a satisfactory value.

CONCLUSION

The reasons for the partly low agreement could be the participants' lack of experience and an inaccurate description of the classification levels. In the end, however, the FFP classification is the only one that meaningfully represents pelvic fractures of geriatric and frail patients. By simplifying to the four main groups, a better interobserver reliability is achieved. For a successful treatment, however, attention to the individual patient and the "fracture personality" is essential.

Percutaneous triangular stabilization of type 3 and type 4 fragility fractures of the pelvis usually leads to fracture healing despite high revision rates

This is a monocentric, retrospective study to analyze radiological findings as well as perioperative and postoperative complications in patients who underwent percutaneous triangular stabilization of type 3 and type 4 fragility fractures of the pelvis. From August 2017 to December 2018, 20 patients were treated surgically. Thirteen patients (65%) were followed-up and received a CT scan of the pelvis after an average time of 14.8 months. A total of 5 patients (38%) had to undergo revision surgery, 2 patients (15%) immediately, 3 patients (23%) in the interval. In 84.6% no fracture line was visible in the sacrum. Fracture healing of the anterior pelvic ring was observed in all cases. Our results show that percutaneous triangular stabilization of type 3 and type 4 fragility fractures of the pelvis usually leads to fracture healing. Radiological signs of loosening were observed in 62%, an implant removal due to symptomatic loosening was necessary in 23%.

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

INTRODUCTION

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

MATERIALS AND METHODS

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

RESULTS

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

CONCLUSIONS

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

[Radiological diagnosis of pelvic ring fractures]

EPIDEMIOLOGY

Traumatic fractures of the pelvic ring are relatively rare, but are associated with increased risk of mortality. Depending on injury mechanism and main vector of energy impact, a distinction is made between anteroposterior compression, lateral compression, and vertical shear (Young and Burgess classification), while the stability-related classification according to Tile distinguishes between type A (stable), type B (rotationally unstable) and type C (completely unstable). A comprehensive modern classification is given by the AO/OTA.

RADIOLOGICAL FRACTURE DIAGNOSIS

Plain pelvis x‑rays lack sufficient sensitivity but are still used to detect highly unstable pelvic fractures. CT has superior sensitivity and specificity. In addition to fracture classification, CT allows reliable assessment of associated vascular and bladder/urethral injuries and large soft tissue hemorrhage. MRI is unparalleled in showing bone marrow edema, cauda and plexus complications, and peripelvic soft tissue damage. MRI may also prove to be a valuable diagnostic tool for pelvic ring injuries in children, adolescents and young women, provided they are hemodynamically stable. Angiography, ultrasonography and bone scintigraphy are additional important diagnostic and therapeutic options.

PRACTICAL RECOMMENDATIONS

Knowledge of basic pelvic trauma mechanisms is important to understand the potential severity of traumatic pelvic fractures and to classify them correctly in terms of stability. Being familiar with typical concomitant injuries in pelvic ring fractures allows reliable diagnosis and their communication with the clinician. CT remains the "diagnostic workhorse". In fragile pelvic fractures, the often prolonged course with fracture progression must be taken into account, which is why MRI is of particular importance herein.

Fragility Fractures of the Pelvic Ring – Does the Evidence of Oedema Lead us to More Surgeries?

Introduction The choice of therapy for fragility fractures of the pelvis (FFP) is largely determined by the diagnosed fracture morphology. It is now unclear whether the change in diagnostic options – sensitive detection of fracture oedema in the sacrum using MRI and dual-energy computed tomography (DECT) – has an impact on the therapeutic consequences. The aim of this retrospective study was therefore to evaluate the change in the diagnostics used and the resulting therapy regimen in our patient population.

Materials and Methods We performed a monocentric-retrospective analysis of 196 patients with a fragility fracture of the pelvis in our clinic (national TraumaZentrum® DGU and SAV approval) in the period from 2008 to 2017. We examined changes in epidemiology, diagnostics/classification and therapy of the pelvic ring fractures treated by us.

Results The diagnostic procedures used are subject to a clear change towards oedema detection using MRI and DECT. The graduation has changed towards more severe forms of fracture after FFP. There is now also an increasing proportion of patients treated by surgery (2008 – 2009: 5.3% vs. 2015 – 2017: 60.3%).

Conclusion We were able to show that the introduction of sensitive diagnostic procedures coincided with a higher classification of the fractures. It is also noteworthy that the increase in operations is not only due to a higher degree of classification; also in relative terms, more patients are operated on within type FFP II.

Risks and Strategies to Avoid Approach-Related Complications During Operative Treatment of Pelvic Ring or Acetabular Fractures

Injuries of the pelvic ring or the acetabulum are either to be found in young patients with high energy trauma mechanisms or in geriatric patients after simple falls with very low impact energy. The indication for surgical stabilization is given by the grade of instability. Exact knowledge of the different possible surgical approaches is essential for the planning of the surgical treatment. Both, knowledge of reachable anatomical structures and possible risks of the different approaches are important. In this review, we summarize the standard surgical approaches to the pelvic ring and to the acetabulum. We describe the reachable anatomical structures for each approach, approach-related pitfalls, and we focus on strategies to reduce approach-related complications.

[Three-point buttressing with internal fixator for minimally invasive stabilization of the anterior pelvic ring : Operative technique and first clinical results]

BACKGROUND

The changing age distribution in society inevitably leads to a percentage increase in osteoporotic and fatigue fractures as well as the absolute number of insufficiency fractures of the pelvic ring. Due to pain these fractures lead to a loss of mobility and autonomy. To prevent these consequences surgical treatment is increasingly being performed.

OBJECTIVE

This article presents a new configuration of an internal fixator on the anterior pelvic ring, the principle of which correlates to a three-point buttressing.

METHODS

In addition to a description of the configuration of the internal fixator on the anterior pelvic ring and the surgical technique, the article presents the results after the first 23 applications.

RESULTS

The first results after application of the new internal fixator on the pelvic ring show a low risk, sufficient and minimally invasive stabilization with an encouraging clinical and radiological outcome.

CONCLUSION

Missing long-term results, also taking into account a higher number of patients, as well as the biomechanical examination of the presented fixator configuration still have to be evaluated.

[3D image enhancer-adjusted percutaneous triangular stabilization of geriatric pelvic ring fractures : Operation technique and indications]

The 3D image enhancer-adjusted percutaneous triangular stabilization of geriatric pelvic ring fractures avoids implant-associated perioperative complications. Displaced fractures of the posterior pelvic ring require stable instrumentation to enable solid bony fusion in a balanced alignment and to control the risk of neurological and vascular damage. This is mandatory in high-energy injuries in young patients and especially in low-energy injuries of geriatric patients. Various surgical techniques have been established. The triangular stabilization technique shows the best biomechanical results. The percutaneous instrumentation reduces access-related morbidity and provides all the benefits of minimally invasive surgery. In order to avoid implant-associated complications, such as vascular and nerve injuries, anatomical and radiological principles are indispensable. The use of 3D image enhancement ensures a safe instrumentation. Nevertheless, pitfalls have to be considered. This article presents the technique of percutaneous triangular stabilization using the 3D scan. After percutaneous insertion of the guide wires into the L4 vertebral body, the iliac bone and transiliosacrally under 2D X‑ray control, the correct wire position is verified by the 3D scan. Then, screws are inserted and the instrumentation is completed in a standard fashion. Using this technique implant-associated perioperative complications, such as nerve and vascular damage due to screw misplacement can be reduced.

[Percutaneous stabilization of the anterior pelvic ring in osteoporotic fractures]

The number of low energy traumas in older people with subsequent pelvic ring fractures is increasing in contrast to high energy traumas with pelvic injury in younger people. Geriatric pelvic fractures can be treated conservatively with analgesics and physiotherapy-assisted mobilization, depending on the symptoms. If physical complaints do not allow adequate mobilization, surgical stabilization is indicated. It is often possible to stabilize the dorsal pelvic ring with transiliosacral screws. If additional instability associated with anterior pelvic ring complaints is prevalent, stabilization of the anterior ring can be achieved by invasive osteosynthesis using a plate or percutaneously by implanting an intramedullary plastic polymer.

Magnetic Resonance Imaging in Pelvic Fractures – Part 1: Which Criteria Lead Us to Supplementary MRI Diagnostics?

Introduction Isolated pelvic fractures are relatively rare with an incidence of 3 – 6% of all fractures, but their incidence in polytraumatized individuals increases to 25%. The S3 guideline Polytrauma gives a clear recommendation for diagnostics by means of pelvic radiography (X-ray) and computed tomography (CT). A recommendation for the diagnosis by means of magnetic resonance tomography (MRI) especially in patients with low energetic/missing trauma does not currently exist. It is unclear on the basis of which criteria the MRI can be indicated in pelvic fractures. The aim of our study was therefore to retrospectively record indications for the indication of MRI in pelvic fractures – with adequate as well as inadequate trauma.

Material and Methods In a retrospective clinical study, a total of 140 patients (median 68 years, range 15 – 97, 75 female, and 66 male) with a pelvic fracture were included in the study over a period of three years. Overall, the trauma mechanism revealed 73 adequate and 67 inadequate fractures. 31/140 patients had undergone MRI of the pelvis in addition to a CT/X-ray scan. The two subgroups “with MRI” and “without MRI” were analyzed with regard to the parameters “sex”, “age”, “adequacy of the trauma”, “fracture localization”, “duration of admission to imaging”, “type of therapy” and “duration to surgery” compared.

Results It was shown that the MRI diagnosis was performed especially in female, elderly patients (81 years, range 19 – 94 years). Patients with inappropriate trauma have received MRI more frequently (74%) than patients with adequate trauma (26%). With regard to fracture localization no differences could be shown. The MRI was performed on a median 4 days after the CT examination. Regarding the decision “conservative” vs. “operationally” our two groups without and with MRT tended to differ not. Patients with MRI were operated on median 2 days later than patients who did not receive MRI.

Conclusions Pelvic fracture MRI should be performed primarily in elderly female patients without adequate trauma. In patients with adequate trauma, MRI is of low value, especially as MRI diagnostics are performed with delay, resulting in later surgery.

Cement augmentation of sacroiliac screws in fragility fractures of the pelvic ring-A synopsis and systematic review of the current literature

BACKGROUND

Fragility fractures of the pelvis (FFP) show a notable rise in prevalence. Minimally invasive surgical fixation of FFP is increasingly advocated for its obvious advantages with reference to early mobilization and weight bearing. Concerns regarding the holding power of osteosynthetic materials in osteoporotic bone led to the development of cementing techniques. However, the role of cement augmentation in the surgical treatment of FFP has yet to be defined. Therefore, the aim of this study was to conduct a systematic review of the current literature concerning studies that are comparing the performance of cement augmented versus non-augmented sacroiliac (SI) screws.

METHODS

We conducted a systematic literature review from 01/01/2000 onwards. Inclusion criteria were randomized controlled studies, case series (n>3), biomechanical studies and reviews, comparing augmented and non-augmented SI screws. Only papers in German or English language were included.

RESULTS

Out of 1247 initial hits, eleven studies met the inclusion criteria. Out of those, six were biomechanical studies and five were clinical case series. Most biomechanical studies showed cement augmented screws to have a greater mechanical stability, both regarding pull-out force and resistance to cyclic loading. The five case studies reported on a total of 98 patients with 122 screw fixations. Three cases of cement leakage into neuroforamina occurred, however, none of these patients showed clinical symptoms.

CONCLUSION

In clinical case series, cement augmentation of SI screws appears to be a safe surgical technique without relevant complications and biomechanical studies demonstrate greater pull-out forces of augmented SI screws but no advantage in regard of cyclic loading. Hence, applicability of the mechanical testing results on the clinical situation are debatable. So far, there are neither retrospective nor randomized controlled studies comparing the performance of cemented and non-cemented SI screws in FFP. Therefore, the clinical benefit of SI screw cement augmentation is unclear and their use remains experimental.

Geriatric Acetabular Surgery: Letournel's Contraindications Then and Now-Data From the German Pelvic Registry

OBJECTIVE

In his original series of 129 surgically treated acetabular fractures, Letournel did not operate on patients older than 60 years. Almost 30 years later, he still emphasized that no patients with reduced bone quality should be operated on. The aim of the study was to analyze epidemiologic characteristics and treatment modes for today's cohort of elderly patients with acetabular fractures.

DESIGN

Retrospective analysis.

SETTING

Multicenter registry/Level I trauma center.

PATIENTS

Three thousand seven hundred ninety-three patients who had sustained a fracture of the acetabulum.

INTERVENTION

Operative and nonoperative treatment of acetabular fractures.

MAIN OUTCOME MEASUREMENTS

Epidemiologic characteristics, treatment mode, in-hospital mortality, rate of secondary hip arthroplasty, and quality of life indicated by EQ-5D score.

RESULTS

For the multicenter registry, more than 50% of all patients with acetabular fractures had an age of 60 years or over. The age peak was found at 75-80 years. Fifty percent of the elderly patients were treated surgically. The in-hospital mortality was significantly higher in elderly patients than patients younger than 60 years. In our Level I trauma center, surgical treatment by open reduction and internal fixation did not influence in-hospital mortality or quality of life of elderly patients with acetabular fractures.

CONCLUSIONS

Today, elderly persons represent the dominant cohort among patients with fractures of the acetabulum. Fifty-five years after the publication of Letournel's original case series, data indicate that currently, surgical treatment is a common and necessary option in the therapy of acetabular fractures in elderly patients.

LEVEL OF EVIDENCE

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

Cement-augmented sacroiliac screw fixation with cannulated versus perforated screws - A biomechanical study in an osteoporotic hemipelvis model

INTRODUCTION

Cement-augmentation is a well-established way to improve the stability of sacroiliac screw fixation in osteoporosis-associated fragility fractures of the posterior pelvic ring. However, to date little is known about the influence of different techniques of cement augmentation on construct stability. The aim of this study was to evaluate the primary stability of cement-augmented sacroiliac screw fixation with cannulated versus perforated screws under cyclic loading.

MATERIALS AND METHODS

A total of eight fresh-frozen human cadaveric hemipelvis specimens with osteoporosis were used. After generating ventral osteotomies on both sides of the sacrum, each specimen was treated using a cement-augmented cannulated screw on one side and a cement-augmented perforated screw on the other side. Afterwards, axial cyclic loading was performed.

RESULTS

No statistically significant difference was found between cannulated and perforated screws concerning maximum load (356.25 N versus 368.75 N, p = 0.749), plastic deformation (1.95 mm versus 1.43 mm, p = 0.798) and stiffness (27.04 N/mm versus 40.40 N/mm, p = 0.645).

CONCLUSIONS

Considering the at least equivalent results for perforated screws, cement augmentation via perforated screws might be an interesting option in clinical practice because of potential advantages, e.g. radiological control before cement application, reduced risk of cement displacement and time saving.

[Traumatology in the elderly : Multimodal prevention of delirium and use of augmentation techniques]

Recent data show that 20-80% of surgery patients are affected by delirium during inpatient clinical treatment. The medical consequences are often dramatic and include a 20 times higher mortality and treatment expenses of the medical unit increase considerably. At the University Hospital of Münster a multimodal and interdisciplinary concept for prevention and management of delirium was developed: all patients older than 65 years admitted for surgery are screened by a specialized team for the risk of developing delirium and treated by members of the team if there is a risk of delirium. Studies proved that by this multimodal approach the incidence of delirium was lowered and therefore the quality of medical care improved.When surgical treatment of fractures in the elderly is required, limited bone quality as well as pre-existing implants can complicate the procedure. Secondary loss of reduction after osteosynthesis and avulsion of the implant in particular must be prevented. Augmentation of the osteosynthetic implant with bone cement can increase the bone-implant interface and therefore stability can be improved. Additional intraoperative 3D imaging can be necessary depending on the localization of the fracture. In biomechanical studies we could prove greater stability in the osteosynthesis of osteoporotic fractures of the distal femur when using additional bone cement; therefore, the use of bone cement is an important tool, which helps to prevent complications in the surgical treatment of fractures in the elderly. Nevertheless, special implants and technical skills are required and some safety aspects should be considered.

Osteoporotic Pelvic Fractures

BACKGROUND

The estimated incidence of osteoporotic pelvic fractures among persons over age 60 in Germany is 224 per 100 000 persons per year, and rising. A number of surgical treatment options are available, but clinical long-term data are lacking.

METHODS

This review is based on pertinent publications and guidelines retrieved by a selective literature search, and on the authors' clinical experience.

RESULTS

Patients often report one or more relatively trivial traumatic incidents leading up to the fracture. They complain of pain in the hip, groin, or lower lumbar region, or of low back pain and sciatica. A new classification scheme entitled Fragility Fractures of the Pelvis (FFP) takes the morphology of the fracture into account and can be used as an aid to therapeutic decision-making (evidence level IV). The goal of treatment is early mobilization with adequate pain relief. Isolated anterior pelvic ring fractures (FFP I) and nondisplaced posterior pelvic ring fractures (FFP II) are usually stable and can be treated conservatively. Type III and IV injuries are unstable and should generally be treated surgically.

CONCLUSION

Retrospective analyses have shown that osteoporotic pelvic fractures are associated with decreased mobility and independence and with a one-year mortality ranging from 9.5% to 27%. Prospective therapeutic trials are urgently needed.

Posterior locked lateral compression injury of the pelvis in geriatric patients: an infrequent and specific variant of the fragility fracture of pelvis

INTRODUCTION

Posterior locked lateral compression injury (PLLCI) of the pelvic ring is an infrequent variant of lateral compression injury, a condition described in only eight reported cases since 2000. Lateral compression injury usually results from high-energy trauma and is characterized by locking between the medially translated fractured ilium and the anterior border of the sacrum, regardless of whether the fractured ilium involves the sacroiliac joint. However, in our experience, lateral compression injury can also result from low-energy trauma as a manifestation of pelvic fragility fracture. The aim of the present study was to describe this rare form of PLLCI in a case series of geriatric patients.

METHODOLOGY

A retrospective analysis of consecutive patients with pelvic ring injuries who were admitted to our hospital from January 2008 to April 2015 identified seven geriatric patients (1 male and 6 females; median age 81 years) with a form of PLLCI.

RESULTS

All injuries were due to falls from a standing position onto the ground. All seven cases demonstrated characteristics of a locking fractured ilium over the anterior border of the sacrum on axial computed tomography images, but were not detected on plain radiographs. All underwent follow-up at 1 year or later with improved mean visual analogue scale scores (range 0-3). Regarding Koval walking ability scores, patients who underwent pelvic brim plating with anterior external fixation were more likely to regain their pre-injury walking ability than patients who only underwent anterior external fixation or conservative treatment.

CONCLUSION

Geriatric patients can experience PLCCIs of the pelvis due to low-energy trauma. These fractures have different characteristics from those associated with severe injuries due to high-energy trauma, and they comprise an infrequent form of Rommens fragility fracture of the pelvis (type IIIa). In these cases, appropriate surgical management that includes sacroiliac plating combined with anterior external fixation can yield good outcomes.

Implementation of a standardized protocol to manage elderly patients with low energy pelvic fractures: can service improvement be expected?

PURPOSE

The incidence of low energy pelvic fractures (FPFs) in the elderly is increasing. Comorbidities, decreased bone-quality, problematic fracture fixation and poor compliance represent some of their specific difficulties. In the absence of uniform management, a standard operating procedure (SOP) was introduced to our unit, aiming to improve the quality of services provided to these patients.

METHODS

A cohort study was contacted to test the impact of (1) using a specific clinical algorithm and (2) using different antiosteoporotic drugs. Multivariate regression analysis was used to determine prognostic factors. Study endpoints were the time-to-healing, length-of-stay, return to pre-injury mobility, union status, mortality and complications.

RESULTS

A total of 132 elderly patients (≥65 years) admitted during the period 2012-2014 with FPFs were enrolled. High-energy fractures, acetabular fractures, associated trauma affecting mobility, pathological pelvic lesions and operated FPFs were used as exclusion criteria. The majority of included patients were females (108/132; 81.8%), and the mean age was 85.8 years (range 67-108). Use of antiosteoporotics was associated with a shorter time of healing (p = 0.036). Patients treated according to the algorithm showed a significant protection against malunion (p < 0.001). Also, adherence to the algorithm allowed more patients to return to their pre-injury mobility status (p = 0.039).

CONCLUSIONS

The use of antiosteoporotic medication in elderly patients with fragility pelvic fractures was associated with faster healing, whilst the adherence to a structured clinical pathway led to less malunions and non-unions and return to pre-injury mobility state.

Biomechanical comparison of augmented versus non-augmented sacroiliac screws in a novel hemi-pelvis test model

Operative treatment of sacral insufficiency fractures is frequently being complicated by osteopenic bone properties. Cement augmentation of implanted sacroiliac screws may lead to superior construct stability and prevent mechanical complications. A novel hemi-pelvis test model with dissected symphysis was developed. Five fresh-frozen cadaveric pelvises were vertically osteotomized at the sacrum on both sides and fixed with sacroiliac screws in both corridors of the first sacral vertebral body. One side was randomly augmented with bone cement. Cyclic testing consisting of torsional loading (±2.5 Nm) combined with progressively increasing axial loading (+50 N compression, -10 N traction, ±0,01 N/cycle) was performed until failure; simulated physiological loads derived from inverse dynamic calculations. The fixation was analyzed fluoroscopically quantifying screw migrations and assessing failure mechanisms. Failure modes were cut-out, pull-out, screw-out, and washer penetration. Motion at fracture site was analyzed via optical motion tracking. Unscrewing was provoked four times with non-augmented and twice with augmented screws. When focusing on the sacral region only, cement augmentation significantly improved screw fixation in terms of increased number of cycles to failure (p = 0.043). However, when considering overall construct stability, there was no significant difference between augmented and non-augmented state due to washer penetration at the iliac bone. The generated hemi-pelvis model was found to be valid due to the reproduction of the clinically observed failure mode (unscrewing). Unscrewing was not fully prevented by cement augmentation. Augmentation effects stability at the screw tip, but particularly in porotic bone, failure may shift to the next weak point. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:1485-1493, 2017.

Pelvic ring fractures in the elderly now and then - a pelvic registry study

OBJECTIVES

To analyze the changes in demographic data stratified for age, sex and type of injury of elderly patients suffering from pelvic ring fractures over a 22-year observation period.

DESIGN/SETTING

Data has been collected prospectively, multi-centrically in hospitals participating in the German Pelvic Trauma Registry.

PATIENTS

We analyzed the data of 5665 patients with an age ≥60years included in the German Pelvic Trauma Registry from 1991 to 2013.

KEY RESULTS

Over the 22-year study period the frequency of type A fractures decreased significantly from 84.8% to 43.9%, while type C and, in particular, type B fractures significantly increased from 7.0% and 8.2% to 14.3% and 41.8%. In patients between 60 and 70 years of age the frequency of type B and C fractures was higher compared to patients >70years. The proportion of female patients, who represent the majority of the cohort (75%), was stable over the entire observation period. Interestingly, type A fractures were found more frequently in females, while type B and C fractures were found more frequently in males.

CONCLUSIONS

With the predicted demographic change and a shift toward more severe injury patterns (type B and C pelvic fractures) in the elderly population, trauma departments will need to develop specific surgical concepts for geriatric patients with pelvic ring fractures.

The incidence of and factors affecting iliosacral screw loosening in pelvic ring injury

INTRODUCTION

Iliosacral screw fixation has been commonly used for stabilization of the posterior ring in unstable pelvic fractures. However, loosening of the screw may develop with or without redisplacement of the fracture. This study was undertaken to evaluate the incidence of iliosacral screw loosening and to identify its predictive factors.

MATERIALS AND METHODS

In total, 110 patients whose posterior pelvic ring was stabilized with iliosacral screws were enrolled. These included 9 cases of anteroposterior compression, 64 cases of lateral compression, and 37 cases of vertical shear (VS) injuries. Among those with posterior pelvic ring injuries, 95 had sacral fractures (zone I: 52, zone II: 43) and 15 had sacroiliac joint dislocations. The screws were fixed to the anterior one-third region of the first sacral (S1) body in 46 cases, and to the middle one-third region in the remaining 64 cases. If loosening of the iliosacral screw influenced the pelvic ring stability, it was considered a failure. The relationship between iliosacral screw loosening and the possible influencing factors were analyzed.

RESULTS

Nineteen patients (17.3 %) were found to have loosening of the iliosacral screw at a mean 25.3 days postoperatively. Of these, 13 patients (11.8 %) had failure of the screws. The incidence of iliosacral screw loosening was significantly higher in those with VS injury (29.7 %, p = 0.014), in those with screw fixed to the middle one-third region of the S1 body (23.4 %, p = 0.044), and in those with VS injury combined with zone II sacral fracture (43.5 %, p = 0.019). With respect to failure of the iliosacral screw, patients with VS injury also had a higher incidence of failure (21.6 %, p = 0.036).

CONCLUSIONS

Our findings demonstrate that cases with VS injuries are prone to screw loosening, especially when combined with zone II sacral fracture. Accordingly, alternative fixation methods should be considered in such cases.

In-screw cement augmentation for iliosacral screw fixation in posterior ring pathologies with insufficient bone stock

BACKGROUND

Minimal invasive screw fixation is common for treating posterior pelvic ring pathologies, but lack of bone quality may cause anchorage problems. The aim of this study was to report in detail a new technique combining iliosacral screw fixation with in-screw cement augmentation (ISFICA).

DESCRIPTION OF TECHNIQUE

The patient was put under general anesthesia and placed in the supine position. A K-wire was inserted under inlet-outlet view to guide the fully threaded screw. The screw placement followed in adequate position. Cement was applied through a bone filler device, inserted at the screwdriver. The immediate control of cement distribution, accurate screw placement and potential leakage were obtained via intraoperative CT scan.

PATIENTS AND METHODS

Twenty consecutive patients treated with ISFICA were included in this study. The mean age was 74.4 years (range 48-98). Screw placement, possible cement leakage and screw positioning were evaluated via intraoperative CT scan. Postoperative neurologic deficits, pain reduction and immediate postoperative mobilization were clinically evaluated.

RESULTS

Twenty-six screws were implanted. All patients were postoperatively, instantly mobilized with reduced pain. No neurologic deficits were apparent postoperatively. No cement leakage occurred. One breach of the iliac cortical bone was noted due to severe osteoporosis. One screw migration was seen after 1 year and two patients showed iliosacral joint arthropathy, which led to screw removal.

CONCLUSION

ISFICA is a very promising technique in terms of safety, precision and initial postoperative outcome. Long-term outcomes such as lasting mechanical stability or pain reduction and screw loosening despite cement augmentation should be investigated in further studies with larger patient numbers.

Sacral Bone Mass Distribution Assessed by Averaged Three-Dimensional CT Models: Implications for Pathogenesis and Treatment of Fragility Fractures of the Sacrum

BACKGROUND

Fragility fractures of the sacrum are increasing in prevalence due to osteoporosis and epidemiological changes and are challenging in their treatment. They exhibit specific fracture patterns with unilateral or bilateral fractures lateral to the sacral foramina, and sometimes an additional transverse fracture leads to spinopelvic dissociation. The goal of this study was to assess sacral bone mass distribution and corresponding changes with decreased general bone mass.

METHODS

Clinical computed tomography (CT) scans of intact pelves in ninety-one individuals (mean age and standard deviation, 61.5 ± 11.3 years) were used to generate three-dimensional (3D) models of the sacrum averaging bone mass in Hounsfield units (HU). Individuals with decreased general bone mass were identified by measuring bone mass in L5 (group 1 with <100 HU; in contrast to group 2 with ≥100 HU).

RESULTS

In group 1, a large zone of negative Hounsfield units was located in the paraforaminal lateral region from S1 to S3. Along the trans-sacral corridors, a Hounsfield unit peak was observed laterally, corresponding to cortical bone of the auricular surface. The lowest Hounsfield unit values were found in the paraforaminal lateral region in the sacral ala. An intermediate level of bone mass was observed in the area of the vertebral bodies, which also demonstrated the largest difference between groups 1 and 2. Overall, the Hounsfield units were lower at S2 than S1.

CONCLUSIONS

The models of averaged bone mass in the sacrum revealed a distinct 3D distribution pattern.

CLINICAL RELEVANCE

The negative values in the paraforaminal lateral region may explain the specific fracture patterns in fragility fractures of the sacrum involving the lateral areas of the sacrum. Transverse fractures located between S1 and S2 leading to spinopelvic dissociation may occur because of decreased bone mass in S2. The largest difference between the studied groups was found in the vertebral bodies and might support the use of transsacral or cement-augmented implants.

Pelvic X-ray misses out on detecting sacral fractures in the elderly - Importance of CT imaging in blunt pelvic trauma

Patients aged 75 years and older with blunt pelvic trauma are frequently seen in the ER. The standard diagnostic tool in these patients is the plain a.p.-radiograph of the pelvis. Especially lesions of the posterior pelvic ring are often missed due to e.g. bowel gas projection and enteric overlay. With a retrospective study covering these patients over a 3 year period in our level I trauma centre, we were able to evaluate the rate of missed injuries in the a.p.-radiograph whenever a corresponding CT scan was performed. Age, gender, and accompanying fractures of the pelvic ring were recorded. The intrinsic test characteristics and the performance in the population were calculated according to standard formulas. Thus, 233 consecutive patients with blunt pelvic trauma with both conventional radiographic examination and computed tomography (CT) were included. Thereof, 56 (23%) showed a sacral fracture in the CT scan. Of 233 pelvic X-ray-images taken, 227 showed no sacral fracture. 51 (21.7%) of these were false negative, yielding a sensitivity of just 10.5%. Average age of patients with sacral fractures was 85.1±6.1 years, with 88% being female. Sacral fractures were often accompanied by lesions of the anterior pelvic ring with pubic bone fractures in 75% of sacrum fracture cases. Second most concomitant fractures are found at the acetabulum (23.3%). Plain radiographic imaging is especially likely to miss out fractures of the posterior pelvic ring, which nowadays can be of therapeutic consequence. Besides the physicians experience in the ED, profound knowledge of insensitivity of plain radiographs in finding posterior pelvic ring lesions is crucial for a reliable diagnostic routine. Since the high mortality caused by prolonged immobilisation due to pelvic ring injuries, all fractures should be identified. We therefore provide a diagnostic algorithm for blunt pelvic trauma in the elderly.

Primary stability of three different iliosacral screw fixation techniques in osteoporotic cadaver specimens-a biomechanical investigation

BACKGROUND

The incidence of osteoporotic and insufficiency fractures of the pelvic ring is increasing. Closed reduction and percutaneous fixation with cannulated sacroiliac screws is well-established in the operative treatment of osteoporotic posterior pelvic ring fractures. However, osteoporotic bone quality might lead to the risk of screw loosening. For this reason, cement augmentation of the iliosacral screws is more frequently performed and recommended.

PURPOSE

The aim of the present biomechanical study was to evaluate the primary stability of three methods of iliosacral screw fixation in human osteoporotic sacrum specimens.

STUDY DESIGN/SETTING

This study used methodical cadaver study.

METHODS

A total of 15 fresh frozen human cadaveric specimens with osteoporosis were used (os sacrum). After matched pair randomization regarding bone quality (T-score), three operation technique groups were generated: screw fixation (cannulated screws) without cement augmentation (Group A); screw fixation with cement augmentation before screw placement (cannulated screws) (Group B); and screw fixation with perforated screws and cement augmentation after screw placement (Group C). In all specimens both sides of the os sacrum were used for operative treatment, resulting in a group size of 10 specimens per group. One operation technique was used on each side of the sacral bone to compare biomechanical properties in the same bone quality. Pull-out tests were performed with a rate of 6 mm/min. A load versus displacement curve was generated.

RESULTS

Subgroup 1 (Group A vs. Group B): Screw fixation without cement augmentation: 594.4 N±463.7 and screw fixation with cement augmentation before screw placement: 1,020.8 N±333.3; values were significantly different (p=.025). Subgroup 2 (Group A vs. Group C): Screw fixation without cement augmentation: 641.8 N±242.0 and perforated screw fixation with cement augmentation after screw placement: 1,029.6 N±326.5; values were significantly different (p=.048). Subgroup 3 (Group B vs. Group C): Screw fixation with cement augmentation before screw placement: 804.0 N±515.3 and perforated screw fixation with cement augmentation after screw placement: 889.8 N±503.3; values were not significantly different (p=.472).

CONCLUSIONS

Regarding iliosacral screw fixation in osteoporotic bone, the primary stability of techniques involving cement augmentation is significantly higher compared with screw fixation without cement augmentation. Perforated screws with the same primary stability as that of conventional screw fixation in combination with cement augmentation might be a promising alternative in reducing complications of cement leakage. These biomechanical results have to be transferred into clinical practice and prove their clinical value.

Low-Trauma Pelvic Fractures in Elderly Finns in 1970-2013

Low-trauma fractures of elderly persons are a major public health problem. However, epidemiologic knowledge on their fresh secular trends is scarce. Trends in the number and incidence (per 100,000 persons) of low-trauma fractures of the pelvic ring among older Finns were assessed by taking into account individuals 80-year-old or older who were admitted to Finnish hospitals for primary treatment of such injury in 1970-2013. The number and age-adjusted incidence of these fractures increased considerably between 1970 and 2013, from 33 (number) and 73 (incidence) in 1970 to 1055 and 364 in 2013. The age-specific incidence of fracture also increased in all age groups (80-84, 85-89, and 90-) of women and men during the entire study period. If the fracture incidence continues to rise at the same rates as in 1970-2013 and the size of the 80-year-old or older population of Finland increases as predicted (87 % by the year 2030), the number low-trauma pelvic fractures in this population will be 2.4 times higher in the year 2030 (2550 fractures) than it was in 2013 (1055 fractures). The number of low-trauma fractures of the pelvis among Finns 80 years of age or older has risen sharply between 1970 and 2013-with a rate that cannot be explained merely by demographic changes. Further studies are urgently needed to better assess the reasons for the rise and possibilities for fracture prevention.

PMMA-augmented SI screw: a biomechanical analysis of stiffness and pull-out force in a matched paired human cadaveric model

INTRODUCTION

Current literature data and clinical experience show that the number of pelvic fractures continuously rises due to the increasing elderly population. In the elderly with suspected osteoporosis additional implant augmentation with bone cement seems to be an option to avoid secondary displacement. There are no reported biomechanical data in the literature comparing the fixation strength (and anchorage) of standard and augmented SI screws so far. The purpose of this study was to assess the biomechanical performance of cement-augmented versus non-augmented SI screws in a human cadaveric pelvis model.

MATERIAL AND METHODS

Six human cadaveric pelvises preserved with the method of Thiel were used in this study. Each pelvis was split to a pair of 2 hemi-pelvises, assigned to 2 different groups for instrumentation with one non-augmented or one contralateral cement-augmented SI screw, placed in the body of S1 in a randomized fashion. The osteosynthesis followed a standard procedure with 3D controlled percutaneous iliosacral screw positioning. A biomechanical setup for a quasistatic pullout test of each SI screw was used. Construct stiffness and maximum pullout force were calculated from the load-displacement curve of the machine data. Statistical evaluation was performed at a level of significance p = .05 for all statistical tests.

RESULTS

Stiffness and pullout force in the augmented group (501.6 N/mm ± 123.7, 1336.8 N ± 221.1) were significantly higher than in the non-augmented one (289.7 N/mm ± 97.1, 597.7 N ± 115.5), p = .04 and p = .014, respectively. BMD influenced significantly the pullout force in all study groups.

CONCLUSION

Cement augmentation significantly increased the fixation strength in iliosacral screw osteosynthesis of the sacrum in a biomechanical human cadaveric model.