How can the orthopedic surgeon ensure optimal vitamin D status in patients operated for an osteoporotic fracture?

In this narrative review, the role of vitamin D deficiency in the pathophysiology, healing of fragility fractures, and rehabilitation is discussed. Vitamin D status can be assessed by measuring serum 25(OH)-vitamin D level with standardized assays. There is a high prevalence of vitamin D insufficiency (25(OH)D < 50 nmol/l (i.e., 20 ng/mL)) or deficiency (25(OH)D < 25 nmol/l (i.e., 10 ng/mL)) in patients with fragility fractures and especially in those with a hip fracture. The evidence on the effects of vitamin D deficiency and/or vitamin D supplementation on fracture healing and material osseointegration is still limited. However, it appears that vitamin D have a rather positive influence on these processes. The fracture liaison service (FLS) model can help to inform orthopedic surgeons, all caregivers, and fractured patients about the importance of optimal vitamin D status in the management of patients with fragility fractures. Therefore, vitamin D status should be included in Capture the Fracture® program as an outcome of FLS in addition to dual-energy X-ray absorptiometry (DXA) and specific antiosteoporosis medication. Vitamin D plays a significant role in the pathophysiology and healing of fragility fractures and in rehabilitation after fracture. Correction of vitamin D deficiency should be one of the main outcomes in fracture liaison services.

Diagnosis, prevention, and treatment of bone fragility in people living with HIV: a position statement from the Swiss Association against Osteoporosis.

Life expectancy of people living with HIV (PLWH) is reaching similar length as in the general population. Accordingly, age-related comorbidities, including osteoporosis, are increasing. Fracture risk is higher and increases approximately 10 years earlier in PLWH. Classical risk factors of bone fragility are highly prevalent in PLWH but factors specific for HIV infection itself and the type of antiretroviral therapy (ART) (triple combination antiretroviral therapy) regimen (especially tenofovir and protease inhibitors) also contribute to bone loss. The majority of bone loss occurs during virus activity and at initiation of ART (immune reconstitution) and is associated with an increase of bone resorption (upregulation RANKL). Recent data indicate that calcium and vitamin D supplements as ART initiation lower BMD loss. The reduction of tenofovir plasma concentrations with tenofovir alafenamide attenuates BMD loss but it remains unknown whether it will contribute to reduce fracture risk. Hence, special considerations for the management of bone fragility in PLWH are warranted. Based on the current state of epidemiology and pathophysiology of osteoporosis in PLWH, we provide the consensus of the Swiss Association against Osteoporosis on best practice for diagnosis, prevention, and management of osteoporosis in this population. Periodic assessment of fracture risk is indicated in all HIV patients and general preventive measures should be implemented. All postmenopausal women, men above 50 years of age, and patients with other clinical risk for fragility fractures qualify for BMD measurement. An algorithm clarifies when treatment with bisphosphonates and review of ART regimen in favour of more bone-friendly options are indicated.

Time-dependent differences in management and microbiology of orthopaedic internal fixation-associated infections: an observational prospective study with 229 patients.

OBJECTIVES: Little information has been published on orthopaedic internal fixation-associated infections. We aimed to analyse time-dependent microbiology, treatment, and outcome. METHODS: Over a 10-year period, all consecutive patients with internal fixation-associated infections at the University Hospital of Basel, were prospectively followed and clinical, microbiological and outcome data were acquired. Infections were classified as early (0-2 weeks after implantation), delayed (3-10 weeks), and late (>10 weeks). RESULTS: Two hundred and twenty-nine patients were included, with a median follow-up of 773 days (IQR 334-1400). Staphylococcus aureus was the most prevalent pathogen (in 96/229 patients, 41.9%). Enterobacteriaceae were frequent in early infections (13/49, 26.5%), whereas coagulase-negative staphylococci (36/92, 39.1%), anaerobes (15/92, 16.3%) and streptococci (10/92, 10.9%) increased in late revisions. Failure was observed in 27/229 (11.7%). Implants were retained in 42/49 (85.7%) in early, in 51/88 (57.9%) in delayed, and in 9/92 (9.8%) in late revisions (p < 0.01). Early revisions failed in 6/49 (12.2%), delayed in 9/88 (10.2%), and late in 11/92 (13.0%) (p 0.81). Debridement and retention failed in 6/42 (14.3%) for early, in 6/51 (11.8%) for delayed, and in 3/9 (33.3%) for late revisions (p 0.21). Biofilm-active antibiotic therapy tailored to resistance correlated with improved outcome for late revisions failure (6/72, 7.7% versus 6/12, 50.0%; p < 0.01) but not for early revisions failure (5/38, 13.2% versus 1/11, 9.1%; p 1.0). CONCLUSIONS: Treatment of internal fixation-associated infections showed a high success rate of 87-90% over all time periods. Implant retention was highly successful in early and delayed infections but only limited in late infections.

[FLS - three letters alter secondary fracture prevention]. / FLS - Drei Buchstaben verändern die sekundäre Frakturprävention.

The increasing importance of preventive measures in the field of orthopedics and trauma surgery becomes apparent because of the demographic changes and the high risk for secondary fractures following osteoporotic fractures. Within the fracture treatment chain, orthopedics and trauma surgery are in the "pole position" to initiate these measures in geriatric patients. In the past orthopedists and trauma surgeons have constantly accused of neglecting secondary fracture prevention in fragility fracture patients. There are several reasons that speak in favor of us undertaking a role in secondary fracture prevention: osteoporosis medication is highly effective in fracture prevention when correctly indicated, the positive effects of osteoporosis therapy on fracture healing and legal issues. Arguments that have been used to justify neglect of secondary fracture prevention are undesired side effects related to osteoporosis medications, such as atypical femoral fractures and osteonecrosis of the jaws, interference of some specific drugs with fracture healing and the working conditions in emergency departments. These run contrary to the consideration of chronic diseases such as osteoporosis, secondary osteoporosis and the underlying disease could be overlooked and the increasing complexity of medicinal osteoporosis therapy. In the first part of the article these arguments are weighed against each other. In the second part the concept of a fracture liaison service (FLS) is discussed. The FLS framework now allows an active role to be taken with respect to secondary fracture prevention despite the busy daily routine schedule. Implementation of an FLS is facilitated by dedicated instruction protocols and programs. Self-financing of an FLS is currently possible only in some specific healthcare systems. In healthcare systems in German-speaking areas a cross-financing must be available and the value of an FLS indirectly presented. Apart from the financial aspects, implementation of a FLS is also worthwhile because it can be looked on as the future driving force of innovation.

Orthogeriatric care pathway: a prospective survey of impact on length of stay, mortality and institutionalisation.

INTRODUCTION: Care pathways for elderly hip fracture patients are increasingly implemented but there has been only limited evaluation of their use. Our objective was to investigate the impact of such a care pathway on the use of healthcare resources and on patients' outcomes. MATERIALS AND METHODS: The prospective survey covered 493 hip fracture patients 65 years of age or older that were treated either before "Usual Care = (UC)" or after "Co-Managed-Care = (CMC)" implementation of the care pathway. Primary outcome was length of stay (LoS). Secondary outcomes were 1-year mortality and change in residential status from prefracture baseline to 1-year after surgery. Data were analysed by descriptive and interferential statistics and adjustment for baseline differences amongst the two patient groups was done. RESULTS: Patients in the CMC sample had more preexisting comorbidities (CCI 2.5 versus 2.1). Prior to the fracture, a larger proportion amongst them needed help in ADL (49 versus 26%), and they were more likely to reside in a nursing home (36 versus 29%). Prefracture mobility status was equal in both samples. In the CMC sample LoS was significantly shorter (LoS 8.6 versus 11.3 days, p < 0.01) and patients were less likely to experience a complication (59 vs 73%, p < 0.01) while being in the hospital. There was no significant difference in 1-year mortality or in change of residential status. CONCLUSIONS: A care pathway for elderly hip fracture patients allowed decreased LoS without affecting mortality or change of residential status 1 year after fracture compared to prefracture baseline.

Literature review of outcome parameters used in studies of Geriatric Fracture Centers.

INTRODUCTION: A variety of multidisciplinary treatment models have been described to improve outcome after osteoporotic hip fractures. There is a tendency toward better outcomes after implementation of the most sophisticated model with a shared leadership for orthopedic surgeons and geriatricians; the Geriatric Fracture Center. The purpose of this review is to evaluate the use of outcome parameters in published literature on the Geriatric Fracture Center evaluation studies. MATERIALS AND METHODS: A literature search was performed using Medline and the Cochrane Library to identify Geriatric Fracture Center evaluation studies. The outcome parameters used in the included studies were evaluated. RESULTS: A total of 16 outcome parameters were used in 11 studies to evaluate patient outcome in 8 different Geriatric Fracture Centers. Two of these outcome parameters are patient-reported outcome measures and 14 outcome parameters were objective measures. CONCLUSION: In-hospital mortality, length of stay, time to surgery, place of residence and complication rate are the most frequently used outcome parameters. The patient-reported outcomes included activities of daily living and mobility scores. There is a need for generally agreed upon outcome measures to facilitate comparison of different care models.

Identifying a standard set of outcome parameters for the evaluation of orthogeriatric co-management for hip fractures.

BACKGROUND AND PURPOSE: Osteoporotic fractures are an increasing problem in the world due to the ageing of the population. Different models of orthogeriatric co-management are currently in use worldwide. These models differ for instance by the health-care professional who has the responsibility for care in the acute and early rehabilitation phases. There is no international consensus regarding the best model of care and which outcome parameters should be used to evaluate these models. The goal of this project was to identify which outcome parameters and assessment tools should be used to measure and compare outcome changes that can be made by the implementation of orthogeriatric co-management models and to develop recommendations about how and when these outcome parameters should be measured. It was not the purpose of this study to describe items that might have an impact on the outcome but cannot be influenced such as age, co-morbidities and cognitive impairment at admission. METHODS: Based on a review of the literature on existing orthogeriatric co-management evaluation studies, 14 outcome parameters were evaluated and discussed in a 2-day meeting with panellists. These panellists were selected based on research and/or clinical expertise in hip fracture management and a common interest in measuring outcome in hip fracture care. RESULTS: We defined 12 objective and subjective outcome parameters and how they should be measured: mortality, length of stay, time to surgery, complications, re-admission rate, mobility, quality of life, pain, activities of daily living, medication use, place of residence and costs. We could not recommend an appropriate tool to measure patients' satisfaction and falls. We defined the time points at which these outcome parameters should be collected to be at admission and discharge, 30 days, 90 days and 1 year after admission. CONCLUSION: Twelve objective and patient-reported outcome parameters were selected to form a standard set for the measurement of influenceable outcome of patients treated in different models of orthogeriatric co-managed care.

[Stabilization of inter- and subtrochanteric femoral fractures with the PFNΑ®]. / Stabilisierung sub- und pertrochantärer Femurfrakturen mit dem PFNΑ®.

OBJECTIVE: Intramedullary nail system fixation of inter- and subtrochanteric femoral fractures allows early weight-bearing, especially in osteoporotic bone. Restoration of anatomical shape and early return to function of the injured leg. INDICATIONS: All inter- and subtrochanteric fractures of AO type 31-A without limitation. CONTRAINDICATIONS: Open physes and unsuitable femoral shaft anatomy (increased anterior bow of femoral shaft or malunion after femoral fracture). SURGICAL TECHNIQUE: If possible closed, otherwise open fracture reduction on a fracture table and unreamed intramedullary nailing. Fixation of the fracture by insertion of a helical blade via a guide wire in the head-neck fragment of the femur. Option of static or dynamic locking at the femoral diaphysis. POSTOPERATIVE MANAGEMENT: Early mobilization immediately the day after surgery with full weight-bearing and use of assistive device, as tolerated. Thrombosis prophylaxis for 6 weeks with fondaparinux, rivaroxaban or a low molecular weight heparin (LMWH), alternatively oral anticoagulation. RESULTS: Between April 2004 and June 2005, the AO multicenter study at 11 European trauma centers included 313 patients (mean age 80.6 years, 77% women, 23% men) with 315 unstable trochanteric fractures treated with a Peroximal Femoral Nail Antirotation® (PFNΑ®) device for consecutive follow-up [24]. In 82%, the fractures were 31-A2, while in 18% the fractures were 31-A3. Average operation time for A2 fractures was 56 min and 66 min for A3 fractures. Average duration of hospital stay in the trauma center was 12 days. Surgical reduction and fracture fixation that permitted full weight-bearing immediately after operation was achieved in 72% of cases. Of 165 complications, 46 were surgery-related with unplanned revision surgery in 28 cases (including 7 femur fractures and 4 acetabular penetrations). Follow-up for more than 1 year was possible in 56% of patients. After 1 year, 89% of the fractures were consolidated. The highest complication rate was found in fractures type 31-A2.3 and in patients older than 90 years. The recorded number of implant-related complications (14.6%) is comparable to the results of other intramedullary and extramedullary implants.

Recent aspects on outcomes in geriatric fracture patients.

As the population ages, the number of fragility fractures is expected to increase dramatically. These injuries are frequently associated with less than satisfactory outcomes. Many of the patients experience adverse events or death, and few regain their pre-injury functional status. Many also lose their independence as a result of their fracture. This manuscript will explore problems and some potential solutions to evaluate the outcomes of geriatric fracture care. Specific, system-wide, and societal concerns will be discussed. Limited suggestions will be made for future steps to improve outcomes assessments.

Ortho-geriatric service--a literature review comparing different models.

In the fast-growing geriatric population, we are confronted with both osteoporosis, which makes fixation of fractures more and more challenging, and several comorbidities, which are most likely to cause postoperative complications. Several models of shared care for these patients are described, and the goal of our systematic literature research was to point out the differences of the individual models. A systematic electronic database search was performed, identifying articles that evaluate in a multidisciplinary approach the elderly hip fracture patients, including at least a geriatrician and an orthopedic surgeon focused on in-hospital treatment. The different investigations were categorized into four groups defined by the type of intervention. The main outcome parameters were pooled across the studies and weighted by sample size. Out of 656 potentially relevant citations, 21 could be extracted and categorized into four groups. Regarding the main outcome parameters, the group with integrated care could show the lowest in-hospital mortality rate (1.14%), the lowest length of stay (7.39 days), and the lowest mean time to surgery (1.43 days). No clear statement could be found for the medical complication rates and the activities of daily living due to their inhomogeneity when comparing the models. The review of these investigations cannot tell us the best model, but there is a trend toward more recent models using an integrated approach. Integrated care summarizes all the positive features reported in the various investigations like integration of a Geriatrician in the trauma unit, having a multidisciplinary team, prioritizing the geriatric fracture patients, and developing guidelines for the patients' treatment. Each hospital implementing a special model for geriatric hip fracture patients should collect detailed data about the patients, process of care, and outcomes to be able to participate in audit processes and avoid peerlessness.

[Bony sacroiliac corridor. A virtual volume model for the accurate insertion of transarticular screws]. / Der sakroiliakale Knochenkorridor. Ein virtuelles Volumenmodell zur sicheren Implantation transartikulärer Schrauben.

BACKGROUND: Minimally invasive sacroiliac (SI) screw fixation carries a high risk for implant malposition. Only idealised shape conceptions of the safe bony corridor exist. METHODS: Two SI corridor models were generated based on a 3D CT reconstruction of a human pelvis. Therefore two penetration depths of the screws into the sacrum were defined. RESULTS: By inserting screws into the centre of the first sacral body an osseous volume of 121 cm3 and an iliac entrance area of 53 cm2 were utilizable. Screw positioning beyond the opposite sacral isthmus leads to a reduction of the bony volume to 72 cm3 (60%) and a decrease of the iliac screw entrance to 20 cm2 (38%). CONCLUSION: The computed realistic 3D models provide exact references to confining bone structures for safe screw positions. The implementation of a software algorithm for fully automated calculation of such volumes based on fluoroscopic or CT images could enhance the performance of computer-assisted navigation systems.

Influence of osteoporosis on fracture fixation--a systematic literature review.

UNLABELLED: The goal of our systematic literature search was to prove whether the experimentally shown influence of osteoporosis on fracture fixation could be confirmed in clinical studies. Despite significant effects in several studies, this is not supported by pooled data due to lack of accurate osteoporosis assessment and complication definitions. INTRODUCTION: The fact that osteoporosis causes fractures is well-known; the assumption that it aggravates their orthopaedic treatment has not been proven. The goal of our systematic literature search was to find out whether the experimentally proven influence of osteoporosis on fracture fixation could be confirmed in clinical studies. METHODS: A systematic electronic database search was performed identifying articles that evaluated complications after fracture fixation among patients suspected of having osteoporosis as measured by BMD or surrogates including Singh index or risk factors. To determine complications risks (relative risk within 95% confidence interval) data were pooled across studies, weighted by sample size and stratified by treatment type. RESULTS: Ten studies out of 77 randomized controlled trials (51 hip, 23 distal radius and three proximal humerus studies) and three systematic reviews finally met eligibility criteria. Despite significant differences of the relative complication risk between osteoporotic and non-osteoporotic patients in several studies, this could not be proven in the pooled data. CONCLUSIONS: In contrast to biomechanical evidence that local osteoporosis affects anchorage of implants, this could not be reproduced in clinical studies, due to the lack of accurate osteoporosis assessment, missing complication definitions and heterogeneous inclusion criteria in these studies. Prospective studies are required that address specifically the correlation between local bone status and the risk of fixation failure.

[Solid body augmentation for comminuted calcaneal fractures : development and biomechanical testing of a hybrid osteosynthesis technique]. / Festkörperaugmentation bei Kalkaneustrümmerfrakturen : Entwicklung und biomechanische Testung einer Hybridosteosynthesetechnik.

BACKGROUND: Comminuted calcaneal fractures are a consequence of high impact trauma to the foot. Stable fixation and anatomically correct repositioning of the joint surfaces are often a problem. To improve fracture treatment, surgical techniques in combination with new augmentation materials have been tested. METHODS: This study presents a new concept of osteosynthesis of complex calcaneal fractures in combination with an alternative augmentation technique. Solid body augmentation was developed and mechanically tested against standard techniques. The solid body was used for augmentation of a central fracture void in combination with conventional plating. RESULTS: The results show a statistically significant higher stability of the new hybrid osteosynthesis concept against conventional plating techniques under in-vitro conditions. CONCLUSIONS: This work investigated a new concept of internal support of multifragmentary calcaneal fractures. Augmentation of defect voids in the calcaneus with a mechanically stable solid body implant in combination with stable screw anchorage in this implant leads to a higher stability compared to plate-fixation and augmentation with cancellous bone under in-vitro conditions.

[Precision of guidewire placement--can it be improved by applying the new, isocentric aiming principle?]. / Können Führungsdrähte durch ein neues isozentrisches Zielverfahren präziser platziert werden?

BACKGROUND: Exact placement of a guidewire is difficult for the less experienced surgeon as this complex 3D task usually is controlled by means of 2D fluoroscopic projections. The new isocentric aiming principle presented here splits up the 3D task into two planar, 2D steps. Movements of the guidewire to achieve correct placement are limited to one plane per step and can therefore be exactly controlled by fluoroscopy. The fluoroscopic projection needs to be changed only once in between the two steps. METHODS: The isocentric aiming principle became applicable to the proximal femur region by means of a mechanical aiming device. We have done an experimental study in order to compare the new isocentric aiming principle to the freehand aiming technique which is routinely applied. We documented the precision of guidewire placement achieved (angular deviation of the guidewire in two projections, linear deviation of the actual from the intended entry point), number of fluoroscopic controls, and procedure time when guidewire placement is done by an experienced and by an inexperienced surgeon. RESULTS: When applying the isocentric aiming principle the inexperienced surgeon succeeded in fixing the entry angle of the guidewire more precisely both in the AP [1.3 degrees (0.0-2.0 degrees ) versus 2.3 degrees (0.0-9.0 degrees ), p=0.034] as well as in the axial view [1.0 degrees (0.0-2.5 degrees ) versus 6.5 degrees (0.0-12.0 degrees ), p=0.036]. Linear displacement was not significantly different between the two methods: 4.4 (0.7-9.6) mm deviation with the isocentric aiming principle versus 3.9 (1.6-5.7) mm, p=0.406, when the freehand technique is applied. When applying the isocentric aiming principle for guidewire placement the experienced surgeon achieved less precise angulation in the AP view [2.5 degrees (0.0-4.0 degrees ) versus 1.8 degrees (0.0-3.5 degrees ), p=0.061], improved precision in the axial view [2.0 degrees (1.0-3.0 degrees ) versus 3.0 degrees (0.0-5.0 degrees ), p=0.074], and a slightly worsened linear displacement [2.5 (1.0-4.2) mm versus 2.0 (1.0-2.6) mm, p=0.131]. Both surgeons needed less fluoroscopic controls when using the isocentric aiming principle instead of the freehand aiming method: inexperienced surgeon: 8.0 controls (7.0-16.0) instead of 13.0 controls (7.0-16.0), p=0.043; experienced surgeon: 14.5 controls (8.0-26.0) instead of 16.5 controls (12.0-33.0), p=0.282. However due to the additional time needed to fix and align the aiming device to the bone both surgeons required increased procedure time when using the isocentric aiming principle: 4.3 (3.0-6.9) min instead of 2.6 (2.2-4.0) min, p=0.005, for the inexperienced surgeon and 3.3 (2.3-4.3) min instead of 1.9 (1.4-2.8) min, p=0.001, for the experienced surgeon. CONCLUSIONS: Based on the experimental results we would suggest clinical application of the isocentric aiming principle especially for the less experienced surgeon. Increased precision would outweigh the drawback of a slightly prolonged procedure time. X-ray exposure may also be reduced when using the isocentric aiming principle for guidewire placement. However our results have to be verified by a clinical study beforehand. The isocentric aiming principle can also be applied in other situations that allow for two orthogonal projections for guidewire placement.

Biomechanical evaluation of a new augmentation method for enhanced screw fixation in osteoporotic proximal femoral fractures.

A biomechanical investigation on eight pairs of human cadaver proximal femurs was performed to evaluate the impact of a new augmentation method on the internal fixation of osteoporotic proximal femur fractures. The study focused on enhancing implant purchase to reduce the incidence of implant cut-out in osteoporotic bone. In a left-right comparison, a conventional hip screw fixation (control) was compared to the new cement augmentation method. After bone bed preparation through high pressure irrigation to remove fat, blood, and bone debris, the bones were augmented with low viscosity polymethylmethacrylate (PMMA) cement. Step-wise fatigue testing was performed by cyclically loading the femoral heads in a physiological manner, beginning at 1,500 N and increasing 500 N every 5,000 cycles to 4,000 N, and continuously monitoring head displacement. Failure was defined as >5.0 mm head displacement. The head displacement at 2,000 N was significantly smaller (p=0.018) for the augmented group as compared to the conventionally treated bones (0.09+/-0.01 mm vs. 0.90+/-0.32 mm; mean+/-SEM). The displacement rate at the second load step was significantly higher (p=0.018) for the conventionally treated bones as compared to the augmented ones. All of the nonaugmented specimens failed during testing, where 50% of the augmented specimens did not fail. The promising results of these experiments suggest that this new standardized irrigation/augmentation method enhances the implant anchorage and offers a potential solution to the problem of implant cut-out in osteoporotic metaphyseal bone.

[Treatment of osteoporosis--the new role of the orthopaedic surgeon]. / Osteoporosebehandlung-- Der Beitrag des Orthopäden/ Unfallchirurgen.

Fractures which are caused by falling from standing height or less are named "fragility fractures". These fractures may indicate neglected osteoporosis and will occur even more frequently in the future, due to the demographic change. This is why osteoporosis will become a challenge to our healthcare systems. For the orthopaedic surgeon treatment of osteoporosis was limited to fracture fixation in the past. As this approach is very focussed towards the fracture as the major complication of osteoporosis, there is a big potential for improvement. It is important to know that such patients suffering from a first fragility fracture are at high risk for being hit by a second or further fragility fractures. A fracture prevention programme should therefore become a mandatory requirement for these patients in the future. The orthopaedic surgeons will be the key players who should put this approach into effect. As we treat most patients with fragility fractures it is our privilege to identify those patients who will most likely benefit from fracture prevention.

Augmentation of osteoporotic bone: effect of pulsed jet-lavage on injection forces, cement distribution, and push-out strength of implants.

Demographic change in the population leads to higher incidence of fragility fractures. Fracture fixation with standard implants may lead to implant cut-out due to reduced purchase. Augmentation of the bone stock with bone cements might overcome this problem. However, cancellous bone infiltration with the viscous cement dough reveals problems of fat embolism or high pressures during application of the cement. This study investigates the improved quality of bovine cancellous bone augmentation when pulsed jet-lavage is used for fat and marrow removal. Parameters such as injection forces, cement dough distribution through cannulated implants and mechanical strength of the fixation were applied for quantification. Injection of 5 mL of acrylic bone cement required significantly lower forces in the lavaged as compared to the untreated bone (50 N vs. > 300 N). Cement distribution was much more homogeneous and push-out forces significantly higher in the pretreated bone group (8.33 +/- 1.41 kN vs. 1.66 +/- 0.63 kN). The application of pulsed jet-lavage for fat removal prior to acrylic cement augmentation led to much more controlled outcomes of the augmentation. This seems to be a relevant step towards safe and efficient injection of bone cements into cancellous bone structures.