Treatment of fractures of the distal radius with a remodellable bone cement: a prospective, randomised study using Norian SRS

Clinical impact of high-profile animal-based research reported in the UK national press

OBJECTIVES

We evaluated animal-based biomedical 'breakthroughs' reported in the UK national press in 1995 (25 years prior to the conclusion of this study). Based on evidence of overspeculative reporting of biomedical research in other areas (eg, press releases and scientific papers), we specifically examined animal research in the media, asking, 'In a given year, what proportion of animal research "breakthroughs"' published in the UK national press had translated, more than 20 years later, to approved interventions?'

METHODS

We searched the Nexis media database (LexisNexis.com) for animal-based biomedical reports in the UK national press. The only restrictions were that the intervention should be specific, such as a named drug, gene, biomedical pathway, to facilitate follow-up, and that there should be claims of some clinical promise.

MAIN OUTCOME MEASURES

Were any interventions approved for human use? If so, when and by which agency? If not, why, and how far did development proceed? Were any other, directly related interventions approved? Did any of the reports overstate human relevance?

RESULTS

Overspeculation and exaggeration of human relevance was evident in all the articles examined. Of 27 unique published 'breakthroughs', only one had clearly resulted in human benefit. Twenty were classified as failures, three were inconclusive and three were partially successful.

CONCLUSIONS

The results of animal-based preclinical research studies are commonly overstated in media reports, to prematurely imply often-imminent 'breakthroughs' relevant to human medicine.

Distal radius fractures in the elderly population

We found no clear evidence of the clinical superiority of distal radius fracture surgery among older adults at one year.

Surgical treatment, however, may yield a faster recovery to previous level of activity in elderly patients.

With operative treatment, hardware-based problems may warrant secondary operations and implant removal, whereas in non-operative treatment, symptomatic loss of alignment and malunion can occur.

In elderly patients, non-operative treatment can be considered to be the gold standard.

Cite this article: EFORT Open Rev 2020;5:361-370. DOI: 10.1302/2058-5241.5.190060

Two casting methods compared in patients with Colles' fracture: A pragmatic, randomized controlled trial

Background

Distal radius fractures are common fractures and the cornerstone of treatment remains immobilization of the wrist in a cast. At present, there is a scarcity of studies that compare different cast immobilization methods. The objective of the study was therefore to compare volar-flexion and ulnar deviation cast to functional cast position in the treatment of dorsally displaced distal radius fracture among elderly patients.

Methods and findings

We performed a pragmatic, randomized, controlled trial in three emergency centers in Finland. After closed reduction of the fracture, the wrist was placed in either volar-flexion and ulnar deviation cast or functional cast position. The follow-up was 12 months. The primary outcome was patient-rated wrist evaluation (PRWE) score at 12 months. The secondary outcomes were Quick-DASH score, grip strength, health-related quality of life (15D), and pain catastrophizing scale. The number of complications was also recorded. In total, 105 participants were included in the study. Of these, 88% were female and the mean age was 73.5 (range 65–94) years. In the primary analysis, the mean difference in patient-rated wrist evaluation measure between groups was -4.9 (95% CI: -13.1.– 3.4., p = .24) in favor of the functional cast position. Operative treatment due to loss of reduction of fracture was performed for four patients (8%) in the FC group and for seven patients (13%) in the volar-flexion and ulnar deviation cast group (OR: 0.63, 95% CI: 0.16–2.1).

Conclusion

In this study, the data were consistent with a wide range of treatment effects when comparing two different cast positions in the treatment of distal radius fracture among elderly patients at 12-month follow-up. However, the functional cast is more likely to be superior when compared to volar-flexion and ulnar deviation cast.

Trial registration

ClinicalTrials.gov identifier: NCT02894983 Accessible: https://clinicaltrials.gov/ct2/show/NCT02894983

Treatment of radius or ulna fractures in the elderly: A systematic review covering effectiveness, safety, economic aspects and current practice

Background

The objective of the present study was to evaluate effectiveness, complications and cost-effectiveness of any surgical or non-surgical treatment for radius or ulna fractures in elderly patients. Secondary objectives were to analyze present treatment traditions of distal radius fractures (DRF) in Sweden and to calculate resource usage for its treatment.

Methods and findings

The assessment contains a systematic review of clinical and health economic studies comparing treatment options for radius or ulna fractures. The results regarding the effectiveness of the treatments are summarized in meta-analyses. In addition, the assessment contains a cost analysis for different treatment options commonly used for DRF care, and an analysis of registry data on the incidence and treatment of DRF. In total 31 randomized controlled trials were included in meta-analyses. When comparing functional outcome for plate fixation versus non-surgical treatment for DRF, there were no clinically important differences at one-year follow-up (mean difference [MD], -3.29, 95% CI, -7.03; 0.44). Similar results were found when comparing plating and percutaneous methods with respect to functional outcome (standardized mean difference [SMD], -0.07, 95% CI, -0.21; 0.07) and grip strength (MD, -3.47, 95% CI, -11.21; 4.28). There were no differences for minor complications, (risk difference [RD], -0.01, 95% CI, -0.07; 0.05) whereas major complications were less common for the percutaneous group, (RD, 0.02, 95% CI, 0.02; 0.03). Given the low number of studies, the evidence above was rated as moderate certainty. The cost for plate fixation versus plaster cast was estimated to 1698 compared to 137 US dollars. For DRF, plate fixation increased in Sweden between 2005 and 2013, and was the most common surgical method in 2013.

Conclusions

Surgical treatment of moderately displaced distal radius fractures in elderly patients offers no clear benefit compared to non-surgical treatment. Plating procedures have become more common during the second millennium and involve higher costs and higher risk of major complications than percutaneous options.

Nanomedicine for safe healing of bone trauma: Opportunities and challenges

Historically, high-energy extremity injuries resulting in significant soft-tissue trauma and bone loss were often deemed unsalvageable and treated with primary amputation. With improved soft-tissue coverage and nerve repair techniques, these injuries now present new challenges in limb-salvage surgery. High-energy extremity trauma is pre-disposed to delayed or unpredictable bony healing and high rates of infection, depending on the integrity of the soft-tissue envelope. Furthermore, orthopedic trauma surgeons are often faced with the challenge of stabilizing and repairing large bony defects while promoting an optimal environment to prevent infection and aid bony healing. During the last decade, nanomedicine has demonstrated substantial potential in addressing the two major issues intrinsic to orthopedic traumas (i.e., high infection risk and low bony reconstruction) through combatting bacterial infection and accelerating/increasing the effectiveness of the bone-healing process. This review presents an overview and discusses recent challenges and opportunities to address major orthopedic trauma through nanomedical approaches.

Minimally-invasive treatment of calcaneal fractures: A review of the literature and our experience

The optimal treatment of calcaneal fractures (CF) is currently controversial and is still under debate. It is well established that conservative treatment of these fractures is associated with poor results. Several surgical techniques are described in the literature; however, there is no consensus on which of these is more effective. The main goals of surgery are to restore the subtalar joint congruence, and calcaneal width, height, shape and alignment, thus avoiding medial and lateral impingement and enabling the patient to resume a normal lifestyle. ORIF is the most popular technique for these fractures, but it is associated with high rates of wound complications, hardware failure and infections. Several minimally-invasive techniques have been developed recently for the treatment of CF, with the common aim to be as simple, effective and inexpensive as possible and to reduce surgical times, complications and length of hospital stay.

Effect of serum-derived albumin scaffold and canine adipose tissue-derived mesenchymal stem cells on osteogenesis in canine segmental bone defect model

Composite biological and synthetic grafts with progenitor cells offer an alternative approach to auto- or allografts for fracture repair. This study was conducted to evaluate osteogenesis of autologous serum-derived albumin (ASA) scaffolds seeded with canine adipose tissue-derived mesenchymal stem cells (Ad-MSCs) in a canine segmental bone defect model. ASA scaffold was prepared with canine serum using cross-linking and freeze-drying procedures. Beta-tricalcium phosphate (β-TCP) was mixed at the cross-linking stage. Ad-MSCs were seeded into the scaffold and incubated for one day before implantation. After 16 weeks, the grafts were harvested for histological analysis. The dogs were divided into five groups: control, ASA scaffolds with and without Ad-MSCs, and ASA scaffolds including β-TCP with and without Ad-MSCs. ASA scaffolds with Ad-MSCs had a significantly larger area of increased opacity at the proximal and distal host cortex-implant interfaces in radiographs 16 weeks after implantation compared to the groups with β-TCP (p < 0.05). Histomorphometric analysis showed that ASA scaffolds with Ad-MSCs had significantly greater new bone formation than other groups (p < 0.05). These results suggest that Ad-MSCs seeded into ASA scaffolds enhanced osteogenesis in the bone defect model, but that β-TCP in the ASA scaffold might prevent penetration of the cells required for bone healing.

Stabilisation of distal radius fractures: Lessons learned and future directions

Our understanding of the diagnosis and management of distal radius fractures has been a long developed over centuries. There has been a shift in treatment of these very common injuries from closed reduction and casting to internal fixation. The answer to the best method of treatment has yet to be found. Today, we have a multitude of treatment options available with varying degrees of evidence to support their use. This review helps to illustrate the lessons we have learned and future directions for treatment.

Management of Severely Comminuted Distal Radius Fractures

Distal radius fractures are among the most common fractures of the upper extremity. Indications for operative and nonsurgical management have evolved over time, as have fixation techniques. Volar locking plates are commonly used in the treatment of selected distal radius fractures such as low-energy or relatively uncomplicated fractures. They have limitations, however, in the management of highly comminuted fracture patterns and in polytrauma patients. In these patients, other methods ranging from spanning fixation to fragment-specific fixation have emerged as useful alternatives in the surgeon's armamentarium for treatment of these challenging fractures.

Balloon-assisted reduction, pin fixation and tricalcium phosphate augmentation for calcanear fracture

Two-thirds of hindfoot fractures involve the calcaneus. The best treatment for intraarticular fractures is still debated. The goal of treatment has been focussed for years on the anatomical reduction of the articular surface. Open reduction and internal fixation enables the surgeon to view the articular surface directly, but it is associated with a high rate of wound breakdown and infection. Therefore, length, width and angular replacement of the great tuberosity are actually the main parameters to consider when treating this type of fracture. This is a report of our experience of 20 patients treated with a minimally invasive technique of reduction using an inflatable bone tamp filled with tricalcium phosphate, with a mean follow-up of 12.25 months (range 7-26 months). Percutaneous K-wires were used to help reduction and to direct balloon inflation. Surgical goals were restoration of the mechanical stability for earlier full weight-bearing and patient mobilisation.

Immediate effects of repetitive wrist extension on grip strength in patients with distal radial fracture

OBJECTIVE

To evaluate the immediate effect of repetitive wrist extension on grip strength in patients with distal radial fracture.

DESIGN

Interventional study.

SETTING

Patients who were admitted to a hospital department of occupational therapy.

PARTICIPANTS

Consecutive patients with a unilateral distal radial fracture (N=28).

INTERVENTION

Each patient was randomly allocated to either the experimental group (n=14) or the control group (n=14). The experimental group performed 30 repetitive wrist extensions with maximal isometric contraction of the extensors of their affected hands during a 6-minute intervention period, whereas the control group did not perform the exercise.

MAIN OUTCOME MEASURES

Grip strength was measured just before and after the intervention period. Pain during grip strength measurements was also quantified using the visual analog scale. Wrist extension strength was measured 10 minutes after the grip strength measurement.

RESULTS

Grip strength increased immediately after repetitive wrist extension in the experimental group, but it remained the same in the control group. Visual analog scale scores indicated that pain was relieved only in the experimental group. However, pain was unrelated to strength production.

CONCLUSIONS

The intervention used in this study might be useful during physical examination to reveal the potential grip strength of patients. The intervention may also be an effective warm-up training procedure in preparation for conventional grip-strengthening exercises.

Self-setting calcium orthophosphate formulations

In early 1980s, researchers discovered self-setting calcium orthophosphate cements, which are bioactive and biodegradable grafting bioceramics in the form of a powder and a liquid. After mixing, both phases form pastes, which set and harden forming either a non-stoichiometric calcium deficient hydroxyapatite or brushite. Since both of them are remarkably biocompartible, bioresorbable and osteoconductive, self-setting calcium orthophosphate formulations appear to be promising bioceramics for bone grafting. Furthermore, such formulations possess excellent molding capabilities, easy manipulation and nearly perfect adaptation to the complex shapes of bone defects, followed by gradual bioresorption and new bone formation. In addition, reinforced formulations have been introduced, which might be described as calcium orthophosphate concretes. The discovery of self-setting properties opened up a new era in the medical application of calcium orthophosphates and many commercial trademarks have been introduced as a result. Currently such formulations are widely used as synthetic bone grafts, with several advantages, such as pourability and injectability. Moreover, their low-temperature setting reactions and intrinsic porosity allow loading by drugs, biomolecules and even cells for tissue engineering purposes. In this review, an insight into the self-setting calcium orthophosphate formulations, as excellent bioceramics suitable for both dental and bone grafting applications, has been provided.

Fixation of distal radius fractures in adults: a review

In patients for whom function is a priority, anatomic reduction and stable fixation are prerequisites for good outcomes. Several therapeutic options exist, including orthopedic treatment and internal fixation with pins (intra- and extrafocal), external fixation which may or may not bridge the wrist, and different internal fixation techniques with dorsal or palmar plates using or not, locking screws. Arthroscopy may be necessary in case of articular fracture. In the presence of significant metaphyseal bone defects, filling of the comminution with phosphocalcic cements provides better graft stability. The level of evidence is too low to allow recommending one type of fixation for one type of fracture; and different fixation options to achieve stable reduction exist, each with its own specific complications. With the new generations of palmar plate, secondary displacement is becoming a thing of the past.

Recommendations and considerations for the use of biologics in orthopedic surgery

Reconstruction of extensive bone defects remains technically challenging and has considerable medical and financial impact on our society. Surgical procedures often require a bone/substitute graft to enhance and accelerate bone repair. Bone autografts are associated with morbidity related to bone harvesting and are limited in quantity. Alternatively, bone allografts expose the patient to the risk of transmission of infectious disease. Synthetic bone graft substitutes, such as calcium sulfates, hydroxyapatite, tricalcium phosphate, and combinations, circumvent some of the disadvantages of auto- and allografts, but have limited indications. Biomedical research has made possible the stimulation of the body's own healing mechanisms, either by delivering exogenous growth factors locally, or by stimulating their local production by gene transfer. Among all known factors having osteoinductive properties, only two bone morphogenetic proteins (for specific indications) and demineralized bone matrix have been approved for clinical use. In addition, ongoing research is exploring the efficacy of cell therapy and tissue engineering. The present report examines the composition, biological properties, indications, clinical experience and regulations of several of the biotherapeutics employed for bone reconstruction.

Use of bone graft substitute in the treatment for distal radius fractures in elderly

INTRODUCTION

Fractures of the distal radius in elderly patients are often associated with metaphyseal defects that can lead to collapse, malunion and therefore decreased function. An alternative approach to simple reduction is to fill the defects with materials that can provide structural support.

METHODS

We used synthetic hydroxyapatite (HA) in unstable fractures of the distal radius in thirty-one elderly patients, of which four patients lost to follow-up, leaving twenty-seven patients for this study. All subjects underwent closed reduction with K-wire fixation and HA augmentation. They were followed up at 8- and 16-week intervals post-operatively to assess the functional outcome using patient-related wrist evaluation [PRWE], clinical outcome and radiological outcome.

RESULTS

At mean 16 weeks, our results show that patients treated with this method showed no metaphyseal defect, no collapse and had satisfactory clinical outcome as assessed by PRWE.

CONCLUSION

We believe that fixation with hydroxyapatite augmentation for fractures of the distal radius in elderly patients is an attractive therapeutic option. This experience has changed our clinical practice.

Bone graft substitutes: What are the options?

Currently, a number of bone grafting materials are available in the clinical setting to enhance bone regeneration, varying from autologous bone to several bone graft substitutes. Although autologous bone remains the "gold standard" for stimulating bone repair and regeneration, the morbidity from its harvesting and its restricted availability generated the need for the development of other materials or strategies either to substitute autologous bone graft or expand its limited supply. Bone graft substitutes can possess one or more components: an osteoconductive matrix, acting as a scaffold; osteoinductive proteins and other growth factors to induce differentiation and proliferation of bone-forming cells; and osteogenic cells for bone formation. Based on their distinct properties, all these bone grafting alternatives have specific indications, and can be used either alone or in combination. In this review, we summarise the available bone grafting materials, focussing mainly on the various bone substitutes and their characteristics, in an effort to specify the indications for their use.

The use of bone grafts and substitutes in the treatment of distal radius fractures

The interest in developing biomaterials to augment fracture healing continues to grow. New products promise early return to function with minimal morbidity; however, indications to use these products remain unclear. An ideal bone graft material stimulates bone healing and provides structural stability while being biocompatible, bioresorbable, easy to use, and cost-effective. This article reviews the biology of bone grafts and the clinical evidence in the use of bone graft substitutes for the treatment of distal radius fractures.

Mechanical characterization of bone graft substitute ceramic cements

The aim of this laboratory work was to study the compressive and flexural characteristics of various commercially available bone graft substitute (BGS) ceramic cements, in their initial as-mixed condition, and compare them to polymethylmethacrylate (PMMA). The tested biomaterials were two different calcium phosphate cements, two different calcium sulphate cements, one nanocrystalline hydroxyapatite and one PMMA cement. All biomaterials were prepared according to manufacturers instructions and the methodology described in ISO 5833 (2002) for acrylic bone cement was followed, as the one closest approaching in vivo requirements. All BGS cements had a brittle behaviour and when subjected to mechanical stress they all failed under sudden crack propagations in their bulk. Both in compression and bending, all BGS cements failed under loads lower than those of PMMA. In compression, the calcium sulphate extra strength cement showed a strength value of approximately 60% of PMMA, the other cements following at a distance. In bending, all BGS cements showed strengths below 22% of PMMA. However, due to limited number and fragility of specimens, calculated bending strengths can only be considered as indicative figures with limited comparative value. The results of this in vitro study showed a varying mechanical performance between tested BGS ceramic cements, whilst all of them exhibited lower compression and bending strength than the selected PMMA. These findings, of course, cannot be directly extrapolated to surgical or clinical implications, since the adopted in vitro context does not necessarily reflect the actual in vivo conditions met by such biomaterials.

Fixation of comminuted distal radius fractures with a mixture of calcium phosphate and calcium sulfate cement

Distal radius fracture alignment and stabilization can be a surgical challenge in the face of severe comminution and bone loss. We describe a technique using a calcium phosphate/sulfate bone cement, as an adjunct to internal fixation. This bone cement is biocompatible, osteoconductive, and sets quickly with an isothermic reaction. The use of bone cement eliminates the need for primary autologous bone grafting and allows for easier reduction and retention of reduction at the time of surgery. Bone cement is employed for the following purposes in comminuted fractures: (1) to fill a void due to lost or crushed cancellous bone, (2) to hold larger unstable fragments while hardware is placed, and (3) to retain fragments too small to take hardware. Available bone cements, studies involving the use of bone cement for distal radius fractures, indications, and surgical technique will be reviewed.

Injectable bone-graft substitutes: current products, their characteristics and indications, and new developments

More than a decade has passed since the first injectable bone substitutes were introduced for use in orthopaedic trauma, and over recent years the number of commercial products has increased dramatically. Despite the fact that these bone substitutes have been on the market for many years, knowledge amongst potential users on how and when they might be useful is still fairly limited. Most injectable bone substitutes belong to one of two major groups: by far the largest group contains products based on various calcium phosphate (CP) mixtures, whilst the smaller group consists of calcium sulphate (CS) compounds. Following mixing, the CP or CS paste can be injected into--for instance--a fracture space for augmentation as an alternative to bone graft, or around a screw for augmentation if the bone is weak. Within minutes an in situ process makes the substitute hard; the mechanical strength in compression resembles that of cancellous bone, whereas the strength in bending and shear is lower. Over time, CP products undergo remodelling through a cell-mediated process that seems to mimic the normal bone remodelling, whilst CS products are dissolved through a faster process that is not cell-mediated. For CP, a number of clinical studies have shown that it can be useful for augmentation of metaphyseal fractures when a space is present. Randomised studies have verified that CP works especially well in tibial plateau fractures when compared with conventional bone grafting. So far the number of clinical studies on CS products is very low. Development at present seems to be heading towards premixed or directly mixed products as well as new compounds that contain fibres or other components to enhance bending and shear strength. Products that are based on combinations of CP and CS are also being developed to combine the fast-dissolving CS with the stronger and more slowly remodelling CP. Injectable bone substitutes, and especially CS, have also been targeted as potentially good carriers for antibiotics and growth factors.

A systematic review of outcomes and complications of treating unstable distal radius fractures in the elderly

PURPOSE

As the population in developed countries continues to age, the incidence of osteoporotic distal radius fractures (DRFs) will increase as well. Treatment of DRF in the elderly population is controversial. We systematically reviewed the existing literature for the management of DRFs in patients aged 60 and over with 5 common techniques: the volar locking plate system, nonbridging external fixation, bridging external fixation, percutaneous Kirschner wire fixation, and cast immobilization (CI).

METHODS

We reviewed articles retrieved from MEDLINE, Embase, and CINAHL Plus that met predetermined inclusion and exclusion criteria in 2 literature reviews. Outcomes of interest included wrist arc of motion, grip strength, functional outcome measurements, radiographic parameters, and the number and type of complications. We statistically analyzed the data using weighted means and proportions based on the sample size in each study.

RESULTS

We identified 2,039 papers and selected 21 papers fitting the inclusion criteria in the primary review of articles with a mean patient age of 60 and older. Statistically significant differences were detected for wrist arc of motion, grip strength, and Disabilities of the Arm, Shoulder, and Hand score, although these findings may not be clinically meaningful. Volar tilt and ulnar variance revealed significant differences among groups, with CI resulting in the worst radiographic outcomes. The complications were significantly different, with CI having the lowest rate of complications, whereas the volar locking plate system had significantly more major complications requiring additional surgical intervention.

CONCLUSIONS

This systematic review suggests that despite worse radiographic outcomes associated with CI, functional outcomes were no different from those of surgically treated groups for patients age 60 and over. Prospective comparative outcomes studies are necessary to evaluate the rate of functional recovery, cost, and outcomes associated with these 5 treatment methods.

Microstructure and biomechanical characteristics of bone substitutes for trauma and orthopaedic surgery

BACKGROUND

Many (artificial) bone substitute materials are currently available for use in orthopaedic trauma surgery. Objective data on their biological and biomechanical characteristics, which determine their clinical application, is mostly lacking. The aim of this study was to investigate structural and in vitro mechanical properties of nine bone substitute cements registered for use in orthopaedic trauma surgery in the Netherlands.

METHODS

Seven calcium phosphate cements (BoneSource®, Calcibon®, ChronOS®, Eurobone®, HydroSet™, Norian SRS®, and Ostim®), one calcium sulphate cement (MIIG® X3), and one bioactive glass cement (Cortoss®) were tested. Structural characteristics were measured by micro-CT scanning. Compression strength and stiffness were determined following unconfined compression tests.

RESULTS

Each bone substitute had unique characteristics. Mean total porosity ranged from 53% (Ostim®) to 0.5% (Norian SRS®). Mean pore size exceeded 100 μm only in Eurobone® and Cortoss® (162.2 ± 107.1 μm and 148.4 ± 70.6 μm, respectively). However, 230 μm pores were found in Calcibon®, Norian SRS®, HydroSet™, and MIIG® X3. Connectivity density ranged from 27/cm3 for HydroSet™ to 0.03/cm3 for Calcibon®. The ultimate compression strength was highest in Cortoss® (47.32 MPa) and lowest in Ostim® (0.24 MPa). Young's Modulus was highest in Calcibon® (790 MPa) and lowest in Ostim® (6 MPa).

CONCLUSIONS

The bone substitutes tested display a wide range in structural properties and compression strength, indicating that they will be suitable for different clinical indications. The data outlined here will help surgeons to select the most suitable products currently available for specific clinical indications.

Bone substitutes in the Netherlands - a systematic literature review

Autologous bone grafting is currently considered as the gold standard to restore bone defects. However, clinical benefit is not guaranteed and there is an associated 8-39% complication rate. This has resulted in the development of alternative (synthetic) bone substitutes. The aim of this systematic literature review was to provide a comprehensive overview of literature data of bone substitutes registered in the Netherlands for use in trauma and orthopedic surgery. Brand names of selected products were used as search terms in three available databases: Embase, PubMed and Cochrane. Manuscripts written in English, German or Dutch that reported on structural, biological or biomechanical properties of the pure product or on its use in trauma and orthopedic surgery were included. The primary search resulted in 475 manuscripts from PubMed, 653 from Embase and 10 from Cochrane. Of these, 218 met the final inclusion criteria. Of each product, structural, biological and biomechanical characteristics as well as their clinical indications in trauma and orthopedic surgery are provided. All included products possess osteoconductive properties but differ in resorption time and biomechanical properties. They have been used for a wide range of clinical applications; however, the overall level of clinical evidence is low. The requirements of an optimal bone substitute are related to the size and location of the defect. Calcium phosphate grafts have been used for most trauma and orthopedic surgery procedures. Calcium sulphates were mainly used to restore bone defects after tumour resection surgery but offer minimal structural support. Bioactive glass remains a potential alternative; however, its use has only been studied to a limited extent.

Stabilization and treatment of Colles' fractures in elderly patients

Colles’ fractures (fractures of the distal radius) are extremely common in the elderly. These fractures tend to result in displacement in elderly people because they have osteoporotic bone. Fracture displacement in the elderly, however, does not necessarily result in functional impairment. This review looks at the current literature on distal radius fractures in the elderly and the treatment options for stabilization of these fractures. These include conservative management with cast immobilization or surgical options: internal fixation, external fixation, percutaneous pinning, and bone substitutes.

Calcium phosphate-based composites as injectable bone substitute materials

A major weakness of current orthopedic implant materials, for instance sintered hydroxyapatite (HA), is that they exist as a hardened form, requiring the surgeon to fit the surgical site around an implant to the desired shape. This can cause an increase in bone loss, trauma to the surrounding tissue, and longer surgical time. A convenient alternative to harden bone filling materials are injectable bone substitutes (IBS). In this article, recent progress in the development and application of calcium phosphate (CP)-based composites use as IBS is reviewed. CP materials have been used widely for bone replacement because of their similarity to the mineral component of bone. The main limitation of bulk CP materials is their brittle nature and poor mechanical properties. There is significant effort to reinforce or improve the mechanical properties and injectability of calcium phosphate cement (CPC) and this review resumes different alternatives presented in this specialized literature.

Effect of hydroxyapatite on bone integration in a rabbit tibial defect model

Background

The aim of the present study was to prepare hydroxyapatite (HA) and then characterize its effect on bone integration in a rabbit tibial defect model. The bone formation with different designs of HA was compared and the bony integration of several graft materials was investigated qualitatively by radiologic and histologic study.

Methods

Ten rabbits were included in this study; two holes were drilled bilaterally across the near cortex and the four holes in each rabbit were divided into four treatment groups (HAP, hydroxyapatite powder; HAC, hydroxyapatite cylinder; HA/TCP, hydroxyapatite/tri-calcium phosphate cylinder, and titanium cylinder). The volume of bone ingrowth and the change of bone mineral density were statistically calculated by computed tomography five times for each treatment group at 0, 2, 4, 6, and 8 weeks after grafting. Histologic analysis was performed at 8 weeks after grafting.

Results

The HAP group showed the most pronounced effect on the bone ingrowth surface area, which seen at 4, 6, and 8 weeks after graft (p < 0.05). On comparing the change of bone mineral density the bone ingrowth surface area among the 4 groups, there were no statistically significant differences among the groups found for any period (p > 0.05). On histological examination, the HAP group revealed well-recovered cortical bone, but the bone was irregularly thickened and haphazardly admixed with powder. The HAC group showed similar histological features to those of the HA/TCP group; the cortical surface of the newly developed bone was smooth and the bone matrix on the surface of the cylinder was regularly arranged.

Conclusions

We concluded that both the hydroxyapatite powder and cylinder models investigated in our study may be suitable as a bone substitute in the rabbit tibial defect model, but their characteristic properties are quite different. In contrast to hydroxyapatite powder, which showed better results for the bone ingrowth surface, the hydroxyapatite cylinder showed better results for the sustained morphology.

Treatment of distal radius fractures

The clinical practice guideline is based on a systematic review of published studies on the treatment of distal radius fractures in adults. None of the 29 recommendations made by the work group was graded as strong; most are graded as inconclusive or consensus; seven are graded as weak. The remaining five moderate-strength recommendations include surgical fixation, rather than cast fixation, for fractures with postreduction radial shortening >3 mm, dorsal tilt >10 degrees , or intra-articular displacement or step-off >2 mm; use of rigid immobilization rather than removable splints for nonsurgical treatment; making a postreduction true lateral radiograph of the carpus to assess dorsal radial ulnar joint alignment; beginning early wrist motion following stable fixation; and recommending adjuvant treatment with vitamin C to prevent disproportionate pain.

External fixation of distal radius fractures

Fractures of the distal radius are the most common fractures that occur in patients between ages 15 and 75 years. Many methods for treating displaced distal radius fractures are available. All forms of treatment involve obtaining fracture reduction, which may then be maintained by casting, functional bracing, external fixation, percutaneous pinning, internal fixation, or a combination of these methods. This article discusses the indications and technique of fracture treatment with external fixation and, when required, adjuvant percutaneous pins.

Evaluation of a novel nanocrystalline hydroxyapatite paste Ostim in comparison to Alpha-BSM - more bone ingrowth inside the implanted material with Ostim compared to Alpha BSM

Background

The purpose of this study was to evaluate the performance a newly developed nanocrystalline hydroxyapatite, OSTIM^® following functional implantation in femoral sites in thirty-eight sheep for 1, 2 or 3 months. Ostim^® 35 was compared to an established calcium phosphate, Alpha BSM^®.

Methods

Biomechanical testing, μ-CT analysis, histological and histomorphological analyses were conducted to compare the treatments including evaluation of bone regeneration level, material degradation, implant biomechanical characteristics.

Results

The micro-computed tomography (μCT) analysis and macroscopic observations showed that Ostim^® seemed to diffuse easily particularly when the defects were created in a cancellous bone area. Alpha BSM^® remained in the defect.

The performance of Ostim was good in terms of mechanical properties that were similar to Alpha BSM^® and the histological analysis showed that the bone regeneration was better with Ostim^® than with Alpha BSM^®. The histomorphometric analysis confirmed the qualitative analysis and showed more bone ingrowth inside the implanted material with Ostim^® when compared to Alpha BSM ^® at all time points.

Conclusions

The successful bone healing with osseous consolidation verifies the importance of the nanocrystalline hydroxyapatite in the treatment of metaphyseal osseous volume defects in the metaphyseal spongiosa.

WITHDRAWN: Surgical interventions for treating distal radial fractures in adults

BACKGROUND

Fracture of the distal radius is a common clinical problem, particularly in older white women with osteoporosis.

OBJECTIVES

To determine when, and if so what type of, surgical intervention is the most appropriate treatment for fractures of the distal radius in adults.

SEARCH STRATEGY

We searched the Cochrane Bone, Joint and Muscle Trauma Group specialised register (November 2002), the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 1, 2003), MEDLINE (1966 to February 2003), EMBASE (1988 to 2003 Week 8), CINAHL (1982 to February 2003), the National Research Register (Issue 1, 2003), PEDro, conference proceedings and reference lists of articles. No language restrictions were applied.

SELECTION CRITERIA

Randomised or quasi-randomised clinical trials involving skeletally mature patients with a fracture of the distal radius, which compared surgical treatment with conservative treatment, different types of surgical intervention or the duration of immobilisation after surgery. The main categories of surgical intervention were external fixation, percutaneous pinning, open reduction and internal fixation, and the insertion of bone scaffolding materials.

DATA COLLECTION AND ANALYSIS

All trials, meeting the selection criteria, were independently assessed by both reviewers for methodological quality. Data were extracted for anatomical, functional and clinical outcomes (including complications). The trials were grouped into categories relating to the main comparisons and types of surgical intervention. Despite clear heterogeneity in the characteristics of comparable trials, pooling of data was undertaken where possible and appropriate.

MAIN RESULTS

Forty eight trials, examining 25 treatment comparisons, met the inclusion criteria of this review. These involved a total of 3371 mainly female and older patients with generally displaced, often comminuted and potentially or evidently unstable fractures. Nearly half of the trials compared surgery with plaster cast immobilisation. Summarising the outcomes was hampered by the variation between the studies in participant characteristics, interventions, quality of trial methodology and reporting, and outcome measurement. Surgical methods were usually associated with better anatomical appearance after fracture healing, but there was inadequate evidence to confirm that these had resulted in better functional and clinical outcomes for the patients.

AUTHORS' CONCLUSIONS

The 48 randomised trials do not provide robust evidence for most of the decisions necessary in the management of these fractures. Although, in particular, there is some evidence to support the use of external fixation or percutaneous pinning, their precise role and methods are not established. It is also unclear whether surgical intervention of most fracture types will produce consistently better long-term outcomes.There is a need for good quality evidence for the surgical management of these fractures.

Calcium Orthophosphate Cements and Concretes

In early 1980s, researchers discovered self-setting calcium orthophosphate cements, which are a bioactive and biodegradable grafting material in the form of a powder and a liquid. Both phases form after mixing a viscous paste that after being implanted, sets and hardens within the body as either a non-stoichiometric calcium deficient hydroxyapatite (CDHA) or brushite, sometimes blended with unreacted particles and other phases. As both CDHA and brushite are remarkably biocompartible and bioresorbable (therefore, in vivo they can be replaced with newly forming bone), calcium orthophosphate cements represent a good correction technique for non-weight-bearing bone fractures or defects and appear to be very promising materials for bone grafting applications. Besides, these cements possess an excellent osteoconductivity, molding capabilities and easy manipulation. Furthermore, reinforced cement formulations are available, which in a certain sense might be described as calcium orthophosphate concretes. The concepts established by calcium orthophosphate cement pioneers in the early 1980s were used as a platform to initiate a new generation of bone substitute materials for commercialization. Since then, advances have been made in the composition, performance and manufacturing; several beneficial formulations have already been introduced as a result. Many other compositions are in experimental stages. In this review, an insight into calcium orthophosphate cements and concretes, as excellent biomaterials suitable for both dental and bone grafting application, has been provided.

Global burden of trauma: Need for effective fracture therapies

Orthopedic trauma care and fracture management have advanced significantly over the last 50 years. New developments in the biology and biomechanics of the musculoskeletal system, fixation devices, and soft tissue management have greatly influenced our ability to care for musculoskeletal injuries. Many therapies and treatment modalities have the potential to transform future orthopedic treatment by decreasing invasive procedures and providing shorter healing times. Promising results in experimental models have led to an increase in clinical application of these therapies in human subjects. However, for many modalities, precise clinical indications, timing, dosage, and mode of action still need to be clearly defined. In order to further develop fracture management strategies, predict outcomes and improve clinical application of newer technologies, further research studies are needed. Together with evolving new therapies, the strategies to improve fracture care should focus on cost effectiveness. This is a great opportunity for the global orthopedic community, in association with other stakeholders, to address the many barriers to the delivery of safe, timely, and effective care for patients with musculoskeletal injuries in developing countries.

Augmented pin fixation with Cortoss for an unstable AO-A3 type distal radius fracture in a patient with a manifest osteoporosis

Distal radius fractures are one of the most common fractures in the elderly females. In this article, we report a case of a distal radius fracture type AO-A3 with dorsal instability, in an older woman with manifest osteoporosis, treated with minimally invasive Cortoss composite and FFS-wires(R). A 63-year-old woman sustained an unstable distal radial fracture of her left wrist after falling from a kitchen step. She underwent an open reduction of the fracture and fixation with two crossed-fixation pins and Cortoss composite. Post-operative plaster cast immobilization was given for 2 weeks, after which the plaster cast and the fixation pins were removed. At 4 weeks follow-up, she had a good functional result of her left wrist, after 11 months there was a complete return of grip strength with also, except for the palmar flexion, a full return of function. We report here the first case of a successful surgical treatment with Cortoss composite of an AO-A3 type distal radius fracture.

The use of calcium phosphate bone cement in fracture treatment. A meta-analysis of randomized trials

BACKGROUND

Available options to fill fracture voids include autogenous bone, allograft bone, and synthetic bone materials. The objective of this meta-analysis was to determine whether the use of calcium phosphate bone cement improves clinical and radiographic outcomes and reduces fracture complications as compared with conventional treatment (with or without autogenous bone graft) for the treatment of fractures of the appendicular skeleton in adult patients.

METHODS

Multiple databases, online registers of randomized controlled trials, and the proceedings of the meetings of major national orthopaedic associations were searched. Published and unpublished randomized controlled trials were included, and data on methodological quality, population, intervention, and outcomes were abstracted in duplicate. Data were pooled across studies, and relative risks for categorical outcomes and weighted mean differences for continuous outcomes, weighted according to study sample size, were calculated. Heterogeneity across studies was determined, and sensitivity analyses were conducted.

RESULTS

We identified eleven published and three unpublished randomized controlled trials. Of the fourteen studies, six involved distal radial fractures, two involved femoral neck fractures, two involved intertrochanteric femoral fractures, two involved tibial plateau fractures, one involved calcaneal fractures, and one involved multiple types of metaphyseal fractures. All of the studies evaluated the use of calcium phosphate cement for the treatment of metaphyseal fractures occurring primarily through trabecular, cancellous bone. Autogenous bone graft was used in the control group in three studies, and no graft material was used in the remaining studies. Patients managed with calcium phosphate had a significantly lower prevalence of loss of fracture reduction in comparison with patients managed with autograft (relative risk reduction, 68%; 95% confidence interval, 29% to 86%) and had less pain at the fracture site in comparison with controls managed with no graft (relative risk reduction, 56%; 95% confidence interval, 14% to 77%). We were unable to compare pain at the bone-graft donor site between the studies because of methodological reasons. Three studies independently demonstrated improved functional outcomes when the use of calcium phosphate was compared with the use of no grafting material.

CONCLUSIONS

The use of calcium phosphate bone cement for the treatment of fractures in adult patients is associated with a lower prevalence of pain at the fracture site in comparison with the rate in controls (patients managed with no graft material). Loss of fracture reduction is also decreased in comparison with that in patients managed with autogenous bone graft.

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

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.

Bone grafts and bone substitutes for treating distal radial fractures in adults

BACKGROUND

Surgical treatment of fractures of the distal radius can involve the implantation of bone scaffolding materials (bone grafts and substitutes) into bony defects that frequently arise after fracture reduction.

OBJECTIVES

To review the evidence from randomised controlled trials evaluating the implanting of bone scaffolding materials for treating distal radial fractures in adults.

SEARCH STRATEGY

We searched the Cochrane Bone, Joint and Muscle Trauma Group Specialised Register (June 2007), the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE and other databases, conference proceedings and reference lists. No language restrictions were applied.

SELECTION CRITERIA

Randomised or quasi-randomised controlled clinical trials evaluating the use of bone scaffolding for treating distal radial fracture in adults.

DATA COLLECTION AND ANALYSIS

Two people independently selected studies and undertook assessment and data collection.

MAIN RESULTS

Ten heterogenous trials involving 874 adults with generally unstable fractures were grouped into six comparisons. No trial had proven allocation concealment. Four trials (239 participants) found implantation of bone scaffolding (autogenous bone graft (one trial); Norian SRS - a bone substitute (two trials); methylmethacrylate cement (one trial)) improved anatomical outcomes compared with plaster cast alone; and two found it improved function. Reported complications of bone scaffolding were transient discomfort resulting from extraosseous deposits of Norian SRS; with surgical removal of one intra-articular deposit. One trial (323 participants) comparing bone substitute (Norian SRS) versus plaster cast or external fixation found no difference in functional or anatomical outcomes at one year. Statistically significant complications in the respective groups were extraosseous Norian SRS deposits and pin track infection. One trial (48 participants with external fixation) found that autogenous bone graft did not significantly change outcome. There was one serious donor-site complication. One trial (21 participants) found some indication of worse outcomes for hydroxyapatite bone cement compared with Kapandji's intrafocal pinning. Three trials (180 participants) found bone scaffolding (autogenous bone graft (one trial); Norian SRS (one trial); methylmethacrylate cement (one trial)) gave no significant difference in functional outcomes but some indication of better anatomical outcomes compared with external fixation. Most reported complications were associated with external fixation; extraosseous deposits of Norian SRS occurred in one trial. One trial (93 participants with dorsal plate fixation) found autografts slightly improved wrist function compared with allogenic bone material but with an excess of donor site complications.

AUTHORS' CONCLUSIONS

Bone scaffolding may improve anatomical outcome compared with plaster cast alone but there is insufficient evidence to conclude on functional outcome and safety; or for other comparisons.

Distal radius fracture management in elderly patients: a literature review

Distal radius fracture management in elderly patients remains without consensus regarding the appropriate treatment or anticipated outcome. Forty-one studies that included at least 10 patients with a minimum mean age of 65 years and that were indexed in Medline or Embase were reviewed. Treatment methods included pins and plaster, external fixation, K-wires, bone cement, and open reduction and internal fixation with plates. The methodological quality of each study was evaluated through use of a grading scale. Despite study heterogeneity, higher rates of infection were noted with external fixation and K-wire stabilization. Stratifying patients into low-demand and high-demand groups may improve the management of distal radius fractures in elderly patients. In sedentary patients with low demands, functional outcomes are good despite the presence of deformity. Patients with higher demands may benefit from fracture stabilization with locking volar plates. Volar plating with fixed-angle screws may be particularly suitable for elderly patients who may take longer to heal a fracture, be more susceptible to pin-track infection, and demonstrate earlier tendon irritation leading to rupture.

Norian craniofacial repair system: compatibility with resorbable and nonresorbable plating materials

BACKGROUND

Choice of bone replacement materials is important when reconstructing large craniofacial defects. Hydroxyapatite cements are often used for such reconstructions. Recent advances in the development of these cements have produced locally applied, in situ hardening materials excellent for use in craniofacial defects. To date, there has been a paucity of data comparing the use of calcium phosphate cements in combination with titanium or resorbable plating systems and their combined biocompatibility. An experimental dog model was used to compare these systems.

METHODS

Two 4 x 4-cm calvarial defects were created in each of 18 mongrel dogs, and defects were reconstructed with calcium phosphate cement with either titanium or resorbable mesh sheets to evaluate their interaction. Specimens were harvested and evaluated histologically for the development of new bone formation at 3, 6, and 12 months.

RESULTS

At 3 months, no differences were noted in the amount of bone formed between titanium and resorbable plating. By 6 months, the resorbable mesh sheet showed delayed bone formation compared with the titanium mesh. At 12 months, bone formation over the resorbable mesh accelerated to be no different from the titanium mesh. Importantly, new bone formation was seen within the monocalcium phosphate cement Norian Craniofacial Repair System on a reliable basis, regardless of mesh plate used.

CONCLUSIONS

There are no long-term adverse effects with the use of Norian cement with either titanium or resorbable mesh. However, further studies need to be conducted to determine why there is an arrested healing phase between 3 and 6 months with the Norian cement and resorbable plating materials.

The use of osteoconductive bone graft substitutes in orthopaedic trauma

Several bone graft substitutes are now available for use in augmenting bone healing following trauma. Many of these products are osteoconductive and are indicated for filling bone defects in conjunction with standard methods of internal and external fixation. Osteoconduction refers to a process in which the three-dimensional structure of a substance is conducive for the ongrowth and/or ingrowth of newly formed bone. Currently used bone graft substitutes that primarily offer osteoconductive properties include coralline hydroxyapatite, collagen-based matrices, calcium phosphate, calcium sulfate, and tricalcium phosphate. These products vary considerably in chemical composition, structural strength, and resorption or remodeling rates. Understanding these differences is important in selecting a bone graft substitute with the properties desired for a specific clinical situation. The limited number of clinical studies and lack of direct-comparison studies between these products require the surgeon to fully understand the properties of each product when choosing a bone graft substitute.

Distal radius osteotomy in the elderly patient using angular stable implants and Norian bone cement

PURPOSE

To report our results after testing the combination of two technologies--angular-stable locking screw implants and Norian SRS cement--in corrective osteotomies of the distal radius in the elderly. This technique eliminates donor site bone-graft morbidity and expands the indications of corrective osteotomies to older patients with osteoporotic bone.

METHODS

Our retrospective series include 6 patients (5 women and 1 man) with an average age of 60 years. Three patients had corrections through a dorsal approach, 1 through a volar approach, and 2 through a combined approach. Two corrections included an intraarticular osteotomy. We used 2.4-mm volar T plates in patients approached volarly and 2.4-mm L and T plates for those approached dorsally; the osseous defect was filled with bone cement (Norian SRS). Range of motion and grip strength were measured at 16 months average follow-up. Standard wrist radiographs were taken to evaluate alignment and determine improvement. At final follow-up, patients completed the Modified Mayo Wrist score, the Modified Gartland and Werley score, and the Disabilities of the Arm, Shoulder, and Hand (DASH) questionnaire.

RESULTS

There were no perioperative complications. All corrective osteotomies healed. One patient required a Darrach procedure at 6 months. The average wrist and forearm motion was 77% of the opposite side and grip strength 88% of the opposite side. The average total correction in the sagittal plane was 22 degrees with all patients returning to neutral or better alignment. The average ulnar variance improvement was 2 mm. Average postoperative DASH was 28 points; average Modified Mayo Wrist score was 68; and the Modified Gartland and Werley score averaged 9 points.

CONCLUSIONS

We believe that corrective osteotomy of the distal radius in the elderly using angular stable implants and Norian calcium phosphate cement is a safe and predictable surgical technique, even in patients with underlying osteoporosis. It eliminates donor site morbidity, and patient-rated outcome measures demonstrated acceptable daily living function return.

External fixation of distal radius fractures

Fractures of the distal radius are the most common fractures that occur in patients between ages 15 and 75 years. Many methods for treating displaced distal radius fractures are available. All forms of treatment involve obtaining fracture reduction, which may then be maintained by casting, functional bracing, external fixation, percutaneous pinning, internal fixation, or a combination of these methods. This article discusses the indications and technique of fracture treatment with external fixation and, when required, adjuvant percutaneous pins.