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.

[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.

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.

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.

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.

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.

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.

Augmentation of implant purchase with bone cements: an in vitro study of injectability and dough distribution.

Vertebroplasty is widely used to treat (augment) osteoporotic fractures of the spine. This technique--with or without metallic implants--might have more widespread indications, if the mechanics of the injection and distribution of the cement dough through cannulated instruments and implants were better understood. This study was performed to investigate injectability of calcium phosphate and acrylic bone cements through implant prototypes, which featured different perforated sleeve designs. Using a custom-made capillary rheometer, the forces needed to inject 10 mL of the cement dough through standard cannulas were measured in the first series of experiments. In the second series, plastic sleeves were attached to the rheometer, simulating the implant. In both series, the dough was injected into ambient laboratory atmosphere, and in the second series, cement distribution was analyzed by means of an optical system. Injection of cement dough through the cannulas required forces between 50 and 400 N in the case of acrylic cements and between 40 and 500 N in case of the calcium phosphate cements. Using different sleeves did not have a significant influence on the distribution of the cement dough around the sleeve. The amount of cement dough injected was reduced when a perforated implant was attached to the cannula. More material was delivered through the proximal holes of the implant, leading to a V-shaped distribution of the cement dough. Among topics to be investigated in future studies is determination of the injectability of cement dough into trabecular bone or bone-like structures.

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.

A whole-body registration-free navigation system for image-guided surgery and interventional radiology.

RATIONALE AND OBJECTIVES: To develop and test an image-guided navigation system in which the base of reference is taken from the imaging modality, here, a helical CT scanner. METHODS: An optical digitizer together with a calibration device is used to measure the transformation matrix between the digitizer reference system and a CT reference system. During intervention, it tracks radiological and surgical tools with tool references. A specific software visually integrates the current tool position with the corresponding image information. In vitro accuracy tests were performed. RESULTS: With helical CT, freehand positioning accuracy was 1.9 +/- 1.1 mm (mean +/- SD) in vitro (n = 718). CONCLUSIONS: The navigation system developed by the authors appears to be feasible for radiological interventions as well as for minimally invasive surgery. It is not limited to a certain procedure, can be used in every region of the body, and is functional after imaging. Intraprocedural scans can be integrated immediately.

Limitations for three-dimensional ultrasound imaging through a bore-hole trepanation.

The intraoperative shift of neuroanatomical landmarks that serve as reference points is an unsolved problem in current neuronavigation. Monitoring the position of these landmarks requires repeated intraoperative imaging. We analyzed the effectiveness of a 3-D ultrasound system for imaging through a bore-hole trepanation. A tissue-mimicking ultrasound phantom and plastic pads with bore-holes were utilized for in vitro tests of the system. Reducing the diameter of the simulated bore-hole decreased the image quality and reduced the field of view. The multiple plane mode of the 3-D ultrasound system allows reconstruction of images in arbitrary imaging planes on the basis of intraoperatively acquired 3-D datasets. Selecting planes that are coplanar with preoperative MRI scans, we were able to identify neuroanatomical landmarks in the reconstructed ultrasound images. Repeated 3-D ultrasound during a procedure might, therefore, allow recognition of a shift of these landmarks.

[Navigation systems for image-guided therapy: A review]. / Navigationsverfahren für die bildgesteuerte Therapie - ein Uberblick.

Navigation systems for image-guided therapy: A review. Navigation is visually interactive targeting based on the simultaneous display of instrument position and of the corresponding two- or three-dimensional image data sets. In this way it unifies anatomic information and therapeutic action. Medical navigation systems (MNS) can simulate realtime image guidance and thereby reduce radiation exposure as well as provide the full range of digital image processing during an intervention. Navigation is based on the tracking of medical instruments in space and the transformation of image, patient, and instrument coordinates into a common reference system. If the patient coordinate system is used as the common base, the process is called patient-based navigation (PBN). If, however, the imaging modality is present in the interventional suite and its reference system is used, modality-based navigation (MBN) results. MBN does not need pre-interventional registration and inherently provides intra-operative imaging. In neurosurgery MNS's have been well established since years. They are in use for frameless biopsies and for minimizing the access morbidity in deeply situated pathologies. Currently there is a fast expansion of navigation into other surgical disciplines, e.g., orthopaedic surgery. The clinical accuracy of an MNS is hard to determine since an independent method of measurement is mostly not available during surgery. Normally, a deviation of below one up to about 5 mm between the display of the MNS and the actual position of an anatomic structure is reported. So far there have been only very few prospective randomized clinical trials between conventional and navigated interventions.

Intraoperative accuracy evaluation of virtual fluoroscopy--a method for application in computer-assisted distal locking.

Virtual fluoroscopy integrates intraoperative C-arm fluoroscopy as an imaging modality for surgical navigation. In the operating room, the conditions for application of virtual fluoroscopy may be impaired. In such situations, the surgeon is interested in an intraoperative check to decide whether the accuracy available is sufficient to perform the scheduled procedure. The test principle is to include an artificial landmark within the fluoroscopic images acquired for virtual fluoroscopy. As this landmark is fixed outside the patient, it can be touched with the referenced tool prior to performing the procedure. A mismatch between the actual tool position at the landmark and the virtual tool position as visualized on the computer screen allows estimation of the system's accuracy. The principle described was designed for detection of inaccuracies resulting from input of nonoptimal data to the navigation system. The method was successfully applied during computer-assisted distal locking of intramedullary implants, and the test principle might be adapted for other applications of virtual fluoroscopy.

Volumetric model determination of the tibia based on 2D radiographs using a 2D/3D database.

We present a new concept with mathematical background for the construction of a three-dimensional (3D) volumetric model of the human tibia based on two conventional orthogonal two-dimensional (2D) radiographic images. This approach is supported by a computer database containing a collection of 80 2D/3D image data sets of individual cadaveric tibiae. For each of these tibiae, the database contains digitized 2D orthogonal radiographic images in both anterior and lateral views, and the corresponding 3D CT data obtained by computerized tomography. To obtain a 3D model of a tibia for a given patient, shape matching is performed. The computer finds the most similar tibia to the patient's tibia among the 2D radiographic images in the database by applying a matching process. To improve accuracy, a 2D image warping procedure can be applied on the slices of the selected bone prior to 3D reconstruction. The warping process is controlled by the contour data of the two orthogonal views. We found that the 3D model thus achieved was useful for virtual preoperative planning and for simulation of the internal fixation of long bones.

Surgical navigation based on fluoroscopy--clinical application for computer-assisted distal locking of intramedullary implants.

OBJECTIVE: Fluoroscopy is used to guide surgical instruments during orthopedic procedures. Radiation exposure and lack of spatial information are drawbacks of this method. Improvements are expected when fluoroscopy-based surgical navigation is used for intraoperative guidance, e.g., in computer-assisted distal locking of intramedullary implants. PATIENTS AND METHODS: The method was applied to 42 interlocking procedures during implantation of the short proximal femoral nail in 27 patients with pertrochanteric femoral fractures. Precision of interlocking, exposure time, operating time, and number of personnel required for computer-assisted distal locking were recorded. RESULTS: One misplaced interlocking screw was observed (2.3%), and contact between the drill bit and the nail during drilling was noticed in 8 cases (19%). The average exposure time was 16 seconds (range 4-42 seconds), and the procedure took an average of 43 min (range 20-70 min). The number of persons required for computer-assisted distal locking was reduced from three to one within the course of the study. CONCLUSIONS: Fluoroscopy-based surgical navigation provided precise intraoperative guidance for computer-assisted distal locking with minimal use of fluoroscopy. The complex system and related procedure times may be drawbacks in this application. Clinical studies are underway to define implants and surgical procedures where intraoperative guidance by fluoroscopy-based surgical navigation is beneficial for the patient and/or surgeon.

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.