The use of BoneSource hydroxyapatite cement for traumatic metaphyseal bone void filling

A novel injectable hydrogel containing polyetheretherketone for bone regeneration in the craniofacial region

Polyetheretherketone (PEEK) is an organic material introduced as an alternative for titanium implants. Injectable hydrogels are the most promising approach for bone regeneration in the oral cavity to fill the defects with irregular shapes and contours conservatively. In the current study, injectable Aldehyde-cellulose nanocrystalline/silk fibroin (ADCNCs/SF) hydrogels containing PEEK were synthesized, and their bone regeneration capacity was evaluated. Structure, intermolecular interaction, and the reaction between the components were assessed in hydrogel structure. The cytocompatibility of the fabricated scaffolds was evaluated on human dental pulp stem cells (hDPSCs). Moreover, the osteoinduction capacity of ADCNCs/SF/PEEK hydrogels on hDPSCs was evaluated using Real-time PCR, Western blot, Alizarin red staining and ALP activity. Bone formation in critical-size defects in rats' cranial was assessed histologically and radiographically. The results confirmed the successful fabrication of the hydrogel and its osteogenic induction ability on hDPSCs. Furthermore, in in vivo phase, bone formation was significantly higher in ADCNCs/SF/PEEK group. Hence, the enhanced bone regeneration in response to PEEK-loaded hydrogels suggested its potential for regenerating bone loss in the craniofacial region, explicitly surrounding the dental implants.

Radiological Analysis of Gentamicin Eluting Synthetic Bone Graft Substitute Used in the Management of Patients With Traumatic Bone Voids

Background

Management of traumatic bone voids has always been challenging. Gentamicin eluting synthetic bone graft substitute (Cerament-G) showed encouraging results in achieving good bone healing with a satisfactory degree of resorption when utilised as a void filler. This study aims to assess the radiological signs of Cerament-G remodelling when used for patients with traumatic bone voids.

Methods

Retrospective data analysis of all patients admitted to our unit between 2015 and 2021 with traumatic bone voids who had Cerament-G applied intraoperatively as a void filler. Postoperative radiographic images of the fracture site at six weeks, three months, six months, and at the final follow-up were reviewed. The radiological signs of Cerament-G integration, percent of void healing at the final follow-up were assessed.

Results

A total of 51 patients (52 fractures) were included in the study. Among them 10 were female and 41 were male with a mean age of 42.7 (11 - 90) years. The mean void size was 6.58 cm³. Mean follow-up duration was 9.73 months. Primary fracture union was achieved in 44 (86.3%) patients. Delayed union was reported in six (11.7%) patients, while one (1.9%) patient had non-union. Twenty-seven (52%) patients had >90% of void healing with normal trabecular bone. Twenty (38.5%) patients had 50-90% void healing with normal bone. Whereas only five (9.5%) patients had less than 50% of void healing.

Conclusion

Cerament-G used as a void filler for patients with traumatic bone void has resulted 98% fracture union rate with good signs of radiological remodelling into a trabecular bone. More than 50% void filling with new trabecular bone was reported in more than 90% of patients. Non-union was reported in only one patient.

Confirmation of Calcium Phosphate Cement Biodegradation after Jawbone Augmentation around Dental Implants Using Three-Dimensional Visualization and Segmentation Software

The use of autologous bone graft for oral rehabilitation of bone atrophy is considered the gold standard. However, the available grafts do not allow a fast loading of dental implants, as they require a long healing time before full functionality. Innovative bioactive materials provide an easy-to-use solution to this problem. The current study shows the feasibility of calcium phosphate cement paste (Paste-CPC) in the sinus. Long implants were placed simultaneously with the cement paste, and provisional prosthetics were also mounted in the same sessions. Final prosthetics and the full loading took place within the same week. Furthermore, the study shows for the first time the possibility to monitor not only healing progression using Cone Beam Computer tomography (CBCT) but also material retention, over two years, on a case study example. The segmented images showed a 30% reduction of the cement size and an increased mineralized tissue in the sinus. Mechanical testing was performed qualitatively using reverse torque after insertion and cement solidification to indicate clinical feasibility. Both functional and esthetic satisfaction remain unchanged after one year. This flowable paste encourages the augmentation procedure with less invasive measure through socket of removed implants. However, this limitation can be addressed in future studies.

Osteoporotic Bone: When and How to Use Augmentation?

The number of fragility fractures is rising, and treatment is a challenge for orthopaedic trauma surgeons. Various augmentation options have been developed to prevent mechanical failure. Different composites can be used based on the fracture type, patient needs, and biomechanical needs. Indications for augmentation are not limited to osteoporotic fractures but can also be performed as a salvage procedure or in pathologic fractures. Biomechanical studies have shown advantages for augmented implants in the spine, proximal femur, and humerus. Clinical studies are preliminary but promising, showing good clinical results after augmentation with reduced mechanical failure and minimal complications.

Bone Grafts, Bone Substitutes, and Orthobiologics: Applications in Plastic Surgery

As reconstructive needs often extend past the soft tissue alone, a plastic surgeon must also be well versed in the methods of bony reconstruction. Understanding of the basic science of fracture healing and the biochemical mechanisms of the different bone grafts, bone substitutes, and orthobiologics is essential to selecting among the many different options available to the modern plastic surgeon. This review provides a broad overview of these different options and the specific applications for plastic surgeons based on anatomic location.

Alternatives to Autologous Bone Graft in Alveolar Cleft Reconstruction: The State of Alveolar Tissue Engineering

Alveolar cleft reconstruction has historically relied on autologous iliac crest bone grafting (ICBG), but donor site morbidity, pain, and prolonged hospitalization have prompted the search for bone graft substitutes. The authors evaluated bone graft substitutes with the highest levels of evidence, and highlight the products that show promise in alveolar cleft repair and in maxillary augmentation. This comprehensive review guides the craniofacial surgeon toward safe and informed utilization of biomaterials in the alveolar cleft.A literature search was performed to identify in vitro human studies that fulfilled the following criteria: Level I or Level II of evidence, ≥30 subjects, and a direct comparison between a autologous bone graft and a bone graft substitute. A second literature search was performed that captured all studies, regardless of level of evidence, which evaluated bone graft substitutes for alveolar cleft repair or alveolar augmentation for dental implants. Adverse events for each of these products were tabulated as well.Sixteen studies featuring 6 bone graft substitutes: hydroxyapatite, demineralized bone matrix (DBM), β-tricalcium phosphate (TCP), calcium phosphate, recombinant human bone morphogenic protein-2 (rhBMP-2), and rhBMP7 fit the inclusion criteria for the first search. Through our second search, the authors found that DBM, TCP, rhBMP-2, and rhBMP7 have been studied most extensively in the alveolar cleft literature, though frequently in studies using less rigorous methodology (Level III evidence or below). rhBMP-2 was the best studied and showed comparable efficacy to ICBG in terms of volume of bone regeneration, bone density, and capacity to accommodate tooth eruption within the graft site. Pricing for products ranged from $290 to $3110 per 5 mL.The balance between innovation and safety is a complex process requiring constant vigilance and evaluation. Here, the authors profile several bone graft substitutes that demonstrate the most promise in alveolar cleft reconstruction.

Reconstruction of Craniomaxillofacial Bone Defects Using Tissue-Engineering Strategies with Injectable and Non-Injectable Scaffolds

Engineering craniofacial bone tissues is challenging due to their complex structures. Current standard autografts and allografts have many drawbacks for craniofacial bone tissue reconstruction; including donor site morbidity and the ability to reinstate the aesthetic characteristics of the host tissue. To overcome these problems; tissue engineering and regenerative medicine strategies have been developed as a potential way to reconstruct damaged bone tissue. Different types of new biomaterials; including natural polymers; synthetic polymers and bioceramics; have emerged to treat these damaged craniofacial bone tissues in the form of injectable and non-injectable scaffolds; which are examined in this review. Injectable scaffolds can be considered a better approach to craniofacial tissue engineering as they can be inserted with minimally invasive surgery; thus protecting the aesthetic characteristics. In this review; we also focus on recent research innovations with different types of stem-cell sources harvested from oral tissue and growth factors used to develop craniofacial bone tissue-engineering strategies.

Circumferential bone grafting around an absorbable gelatin sponge core reduced the amount of grafted bone in the induced membrane technique for critical-size defects of long bones

OBJECTIVES

The objectives of the study were to introduce a circumferential bone graft around an absorbable gelatin sponge core using an induced membrane technique, to assess its ability to reduce the required amount of graft and to maintain the bone graft, and to evaluate the clinical outcomes in the management of critical-size bone defects.

PATIENTS AND METHODS

Circumferential bone grafting using a staged induced membrane technique for managing critical-size bone defects was performed in 21 patients. Postoperative computed tomography scans were performed 7days after Hemovac drain removal and 3 months after bone grafting. Volumetric measurements of the defect size, gelatin sponge proportion, and amount of grafted bone were performed by two independent observers using three-dimensional (3D) software.

RESULTS

The critical-size defects were located at the metadiaphyseal area of 11 tibias, eight femurs, and two humeri. The average defect size was 8.9cm in length and 65.2cm³ in volume. The absorbable gelatin sponge core replaced 21.4% (average) of the defect volume. There was no significant deterioration in the shape of the grafted bone among the serial 3D models. Eighteen patients (86%) were healed radiographically at 9.1 months (average).

CONCLUSION

Our study suggests that circumferential bone grafting in association with the induced membrane technique could reduce the required amount of bone graft and adequately maintain graft position and shape, with favourable clinical outcomes.

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.

Nanohydroxyapatite promotes the healing process in open-wedge high tibial osteotomy: A CT study

BACKGROUND

The aim of this prospective and randomized study was to evaluate the effectiveness of adding nanohydroxyapatite (NHA) to heterologous bone graft in open wedge high tibial osteotomy (OWHTO) by measuring the bone density of the tibial osteotomy gap.

METHODS

Twenty-seven patients (26 knees) were operated by OWHTO and randomly divided into two groups: pure graft group, in which the osteotomy gap was filled with only heterologous bone graft; nanohydroxyapatite group, in which the osteotomy gap was filled with heterologous bone graft and NHA. All patients underwent computed tomography (CT) examination within one week after operation (Time 0), and after two months (Time 1) and 12months (Time 2). CT volume acquired Hounsfield Units (HU) were calculated and the mean value of bone density on three planes was measured.

RESULTS

At Time 0, the mineral density of the nanohydroxyapatite group appeared significantly higher compared with the pure graft group, due to the presence of NHA. At Time 1, the mineral density of the nanohydroxyapatite group had decreased relative to Time 0, while in the pure graft group it remained unchanged. At Time 2, the mineral density in the nanohydroxyapatite group had further decreased, reaching values close to the mineral density of normal bone. In contrast, in the pure graft group the mineral density had increased, probably due to the lack of reabsorption of the graft and the development of sclerosis in the osteotomy borders.

CONCLUSIONS

The results of the present study show better osseointegration of the heterologous graft when nanohydroxyapatite is added.

Whole-scalp EEG mapping of somatosensory evoked potentials in macaque monkeys

High-density scalp EEG recordings are widely used to study whole-brain neuronal networks in humans non-invasively. Here, we validate EEG mapping of somatosensory evoked potentials (SSEPs) in macaque monkeys (Macaca fascicularis) for the long-term investigation of large-scale neuronal networks and their reorganisation after lesions requiring a craniotomy. SSEPs were acquired from 33 scalp electrodes in five adult anaesthetized animals after electrical median or tibial nerve stimulation. SSEP scalp potential maps were identified by cluster analysis and identified in individual recordings. A distributed, linear inverse solution was used to estimate the intracortical sources of the scalp potentials. SSEPs were characterised by a sequence of components with unique scalp topographies. Source analysis confirmed that median nerve SSEP component maps were in accordance with the somatotopic organisation of the sensorimotor cortex. Most importantly, SSEP recordings were stable both intra- and interindividually. We aim to apply this method to the study of recovery and reorganisation of large-scale neuronal networks following a focal cortical lesion requiring a craniotomy. As a prerequisite, the present study demonstrated that a 300-mm² unilateral craniotomy over the sensorimotor cortex necessary to induce a cortical lesion, followed by bone flap repositioning, suture and gap plugging with calcium phosphate cement, did not induce major distortions of the SSEPs. In conclusion, SSEPs can be successfully and reproducibly recorded from high-density EEG caps in macaque monkeys before and after a craniotomy, opening new possibilities for the long-term follow-up of the cortical reorganisation of large-scale networks in macaque monkeys after a cortical lesion.

In situ gelation of PEG-PLGA-PEG hydrogels containing high loading of hydroxyapatite: in vitro and in vivo characteristics

Thermosensitive hydrogels are renowned carriers that are used to deliver a variety of drugs with the aim of combating diseases. In this study, the injectability of thermosensitive hydrogels comprised of poly(ethylene glycol)-poly(lactic acid-co-glycolic acid)-poly(ethylene glycol) (PEG-PLGA-PEG, PELGE) and hydroxyapatite (HA) were examined for their ability to deliver bone morphological protein 2 (BMP-2). The physicochemical characteristics of PELGE, HA, and PELGE/HA hydrogel composites were investigated by (1)H NMR, GPC, FTIR, XRD, SEM, and TEM. The rheological properties, injectability, in vitro degradation, and in vivo biocompatibility were investigated. The hydrogel with a weight ratio of 4:6 of polymer to HA was found to be resistant to auto-catalyzed degradation of acidic monomers (LA, GA) for a period of 70 days owing to the presence of alkaline HA. Injectability was quantitatively determined by the ejected weight of the hydrogel composite at room temperature and was a close match to the weight amount predetermined by the syringe pump. The results not only revealed that the PELGE/HA hydrogel composite presented a minor tissue response in the subcutis of ICR mice at eight weeks, but they also indicated an acceptable tolerance of the hydrogel composite in animals. Thus, PELGE/HA hydrogel composite is expected to be a promising injectable orthopedic substitute because of its desirable thermosensitivity and injectability.

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.

Bone graft substitutes currently available in orthopaedic practice: the evidence for their use

We reviewed 59 bone graft substitutes marketed by 17 companies currently available for implantation in the United Kingdom, with the aim of assessing the peer-reviewed literature to facilitate informed decision-making regarding their use in clinical practice. After critical analysis of the literature, only 22 products (37%) had any clinical data. Norian SRS (Synthes), Vitoss (Orthovita), Cortoss (Orthovita) and Alpha-BSM (Etex) had Level I evidence. We question the need for so many different products, especially with limited published clinical evidence for their efficacy, and conclude that there is a considerable need for further prospective randomised trials to facilitate informed decision-making with regard to the use of current and future bone graft substitutes in clinical practice.

Antimicrobial surfaces for craniofacial implants: state of the art

In an attempt to regain function and aesthetics in the craniofacial region, different biomaterials, including titanium, hydroxyapatite, biodegradable polymers and composites, have been widely used as a result of the loss of craniofacial bone. Although these materials presented favorable success rates, osseointegration and antibacterial properties are often hard to achieve. Although bone-implant interactions are highly dependent on the implant's surface characteristics, infections following traumatic craniofacial injuries are common. As such, poor osseointegration and infections are two of the many causes of implant failure. Further, as increasingly complex dental repairs are attempted, the likelihood of infection in these implants has also been on the rise. For these reasons, the treatment of craniofacial bone defects and dental repairs for long-term success remains a challenge. Various approaches to reduce the rate of infection and improve osseointegration have been investigated. Furthermore, recent and planned tissue engineering developments are aimed at improving the implants' physical and biological properties by improving their surfaces in order to develop craniofacial bone substitutes that will restore, maintain and improve tissue function. In this review, the commonly used biomaterials for craniofacial bone restoration and dental repair, as well as surface modification techniques, antibacterial surfaces and coatings are discussed.

The utility of calcium phosphate cement in cranioplasty following retromastoid craniectomy for cranial neuralgias

BACKGROUND

Following retromastoid craniectomy for microvascular decompression of the fifth or seventh cranial nerve, the preferred method and value of cranioplasty remains disputed.

METHODS

In this study, we report the functional outcome of calcium phosphate cranioplasty following first-time microvascular decompression in 79 consecutive patients who underwent operations over a one-year period.

RESULTS

No patient experienced a deep infection, cerebrospinal fluid leak or undue incisional pain at long-term follow-up. Additionally, all patients stated that they were satisfied with the cosmetic outcome.

DISCUSSION

Although this technique is unlikely to affect the rates of infection and postoperative pain, we believe that the low rate of CSF leak provides a unique advantage over other currently used methods of closing retromastoid craniectomies.

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.

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.

Synthesis and characterization of injectable, thermosensitive, and biocompatible acellular bone matrix/poly(ethylene glycol)-poly (ε-caprolactone)-poly(ethylene glycol) hydrogel composite

In orthopedic tissue engineering, the extensively applied acellular bone matrix (ABM) can seldom be prefabricated just right to mold the cavity of the diverse defects, might induce severe inflammation on account of the migration of small granules and usually bring the patients great pain in the treatment. In this study, a new injectable thermosensitive ABM/PECE composite with good biocompatibility was designed and prepared by adding the ABM granules into the triblock copolymer poly(ethylene eglycol)-poly(ε-caprolactone)-poly(ethylene eglycol) (PEG-PCL-PEG, PECE). The PECE was synthesized by ring-opening copolymerization and characterized by ¹H NMR. The ABM was prepared by acellular treatment of natural bone and ground to fine granules. The obtained ABM/PECE composite showed the most important absorption bands of ABM and PECE copolymer in FT-IR spectroscopy and underwent sol-gel phage transition from solution to nonflowing hydrogel at 37°C. SEM results indicated that the ABM/PECE composite with different ABM contents all presented similar porous 3D structure. ABM/PECE composite presented mild cytotoxicity to rat MSCs in vitro and good biocompatibility in the BALB/c mice subcutis up to 4 weeks. In conclusion, all the results confirmed that the injectable thermosensitive ABM/PECE composite was a promising candidate for orthopedic tissue engineering in a minimally-invasive way.

Bone graft substitutes for articular support and metaphyseal comminution: what are the options?

Subchondral and metaphyseal bone defects pose a great challenge for the Orthopaedic surgeon not only because the support for the articular surface has been lost but also because the mechanism for the nourishment of articular cartilage through the subchondral plate is distorted. A number of options are available to the surgeons, none of them perfect. Autografting has an appreciable high rate of harvest site morbidity, allograft is associated with infection transmission and host immunologic response. These realities have stimulated interest in supplying bone replacement materials (demineralised bone matrix, synthetic bone substitutes, bone morphogenic proteins). This paper presents the indications and applications of bone substitutes for metaphyseal defects and subchondral support in orthopaedic trauma.

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.

Bone void fillers

For this technology overview, the tools of evidence-based medicine were used to summarize information on the effectiveness and clinical outcomes related to the usage of bone void fillers- specifically, synthetic graft materials. Comprehensive literature searches were conducted to address five key questions, which the task force that prepared the report posed as follows. Question 1 addressed the use of synthetic bone void fillers alone. Question 2 was designed to determine whether synthetic bone void fillers could successfully serve as graft extenders and eliminate the need for iliac crest bone graft. Questions 3, 4, and 5 addressed the use of allografts as a comparison with synthetic fillers because clinical results with allografts are perceived as being much closer to autografts in these areas of the spine.

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.

Bone regeneration using an acellular extracellular matrix and bone marrow mesenchymal stem cells expressing Cbfa1

To treat bone defects, tissue-engineering methods combine an appropriate scaffold with cells and osteogenic signals to stimulate bone repair. Mesenchymal stem cells (MSCs) derived from adult bone marrow are an ideal source of cells for tissue engineering, in particular for applications in skeletal and hard tissue repair. Core binding factor alpha1 (Cbfa1) is an essential transcription factor for osteoblast differentiation. However, the effects of Cbfa1 on MSCs in vitro and in vivo have not been well characterized. In this study, we found that MSCs modified genetically to express Cbfa1 promoted the healing of segmental defects of the radius in rabbits. First, osteogenic differentiation of MSCs transfected with an adenovirus encoding Cbfa1 was demonstrated. Expression of mRNA from a number of osteoblastic marker genes, including osteocalcin, osteopontin, and type I collagen, was detected. In addition, alkaline phosphatase activity and increased osteocalcin content were observed. The cells expressing the Cbfa1 gene were then combined with acellular bone extracellular matrix in a flow perfusion culture system. Finally, the cell-matrix constructs were implanted into radius defects in the rabbit model. After 12 weeks, radiographic, histological, and biomechanical analyses showed that MSCs modified with the Cbfa1 gene resulted in a significantly higher amount of newly-formed bone and rebuilding of the marrow cavity than control cell-matrix constructs. This study indicates that MSCs modified with the Cbfa1 gene can act as suitable seed cells for the regeneration of bone defects.

Injection laryngoplasty with calcium phosphate cement

Objective: To assess the feasibility of injection laryngoplasty with calcium phosphate cement (CPC), which is an injectable paste, self-hardening, and which recrystallizes to calcium hydroxylapatite after injection.

Study Design: A case series with planned data collection.

Methods: Fifty-six patients with unilateral vocal fold paralysis, who received injection laryngoplasty with CPC between August 2003 and August 2007 with a minimum follow-up period of six months, were enrolled in this study. Volumetric and migration analysis for injected CPC were performed using CT after surgery. Vocal function was also assessed by GRBAS subjective voice assessment scale and maximum phonation time (MPT), acoustic analysis including period perturbation quotient (PPQ), amplitude perturbation period (APQ), and noise-to-harmonics ratio (NHR).

Results: No remarkable migration or absorption of injected CPC was observed on CT up to two years after surgery. The average remaining volume of CPC was 87.8% ± 5.3% two years after injection compared to immediately after injection. Significant improvements in GRBAS scales, MPT, PPQ, APQ, and NHR were observed postoperatively. No adverse effects were observed.

Conclusions: Our clinical experience revealed that CPC was safe, nonabsorbable, and effective. Injection laryngoplasty with CPC may be a useful option in the treatment of glottic insufficiency.

Long-term evaluation of a calcium phosphate bone cement with carboxymethyl cellulose in a vertebral defect model

We investigated histological and compressive properties of a calcium phosphate bone cement (BoneSource (CPC); Stryker Orthopaedics, Mahwah, New Jersey) plus carboxymethyl cellulose (CMC) using a sheep vertebral bone void model. Bone voids were surgically created in L3 and L5 in each of 40 sheep, and the voids were filled with the cement. Histological and radiographic evaluations were performed on one vertebral body from each animal at either: 0, 3, 6, 12, 24, or 36 months after surgery; mechanical testing was performed on operated and non-operated vertebral bodies from 35 sheep. Undecalcified sections were digitized, and the area of the original defect, new bone formation, empty space, fibrous tissue, and residual cement were quantified with histomorphometry. Decalcified sections were evaluated qualitatively. The cement was biocompatible, extremely osteoconductive and underwent steady resorption and replacement by bone and bone marrow. Histomorphometry showed variations in the rate of cement remodeling among animals in each time group, but on average, at 36 months the original defect area was occupied by approximately 14% bone, 82% cement, and 4% bone marrow. Even in animals that had greater resorption of cement, there was good bone ingrowth with no fibrous tissue. Compressive testing did not reveal a significant difference in the mechanical properties between vertebral bodies augmented with cement and non-augmented controls, irrespective of the postoperative time. BoneSource mixed with CMC had adequate osteoconductivity, biocompatibility, and adequate compressive strength. There was variability among animals, but histology suggests that considerable cement was still present in most samples after 36 months.

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.

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.

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.

An in vitro optimized injectable calcium phosphate cement for augmenting screw fixation in osteopenic goats

This study reports the proportioning and standardized mixing procedures for preparing a hydroxylapatite cement (tetracalcium phosphate and dicalcium phosphate) of desired viscosity and mechanical strength reproducibly for application in trauma surgery. The behavior and the biomechanical properties of the resulting bone cement in screw augmentation were then evaluated in our osteopenic goat model. The use of a shaker standardized the mixing procedure. The optimal volume of Na2HPO4 used to prepare the injectable cement was 0.45 mL/g, with averaged in vitro compressive strength of 48.29 +/- 5.62 MPa. Histology showed increasing tightly-coupled bone apposition on the cement surface without fibrous encapsulation as observed in the screw-only controls with time in the osteopenic goat model. The cement increased the initial screw pull-out force (54.7%, p = 0.005) significantly and the energy required to failure (54.7%, p < 0.05) significantly, and remained higher than the screw-only controls after 3 months (9.8% and 20.2%, respectively) and 6 months (20.2% and 44.7%, respectively). These results imply potential in the prevention of interfacial micromotions and subsequent fibrous tissue formation at the implant-bone interface resulting in a decreased risk of implant failure. The optimized cement in this study may serve as a good candidate for augmenting fixation of osteoporotic bone.

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.

PMMA is superior to hydroxyapatite for colony reduction in induced osteomyelitis

Staphylococcus aureus infection is a serious complication in patients receiving orthopaedic implants. Treatment with antibiotic-loaded cements can deliver high local concentrations and reduce toxic side effects associated with systemic antibiotic administration, but polymethylmethacrylate cement is nondegradable and may necessitate additional surgery for removal. Previous studies provide support for hydroxyapatite as a biodegradable carrier, but consensus has not been achieved. We hypothesized vancomycin-loaded hydroxyapatite was superior to vancomycin-loaded polymethylmethacrylate in reducing the number of bacterial colony-forming units in the setting of osteomyelitis. Osteomyelitis was induced in rats using an established model. Animals then were randomly assigned to a control group (no antibiotics), a group treated with vancomycin-loaded polymethylmethacry-late, and two groups treated with hydroxyapatite loaded with either low-dose or high-dose vancomycin. After 6 weeks we compared the number of colony-forming units per gram of harvested bone between groups. Vancomycin-loaded hydroxyapatite was inferior to vancomycin-loaded polymethylmethacrylate in reducing the number of bacterial colony-forming units and vancomycin-loaded polymethylmethacry-late was superior to the control group. We observed no difference between low- and high-dose vancomycin-loaded hydroxyapatite groups. The poor handling properties of hydroxyapatite paste may explain these findings. Based on these results, a hydroxyapatite carrier cannot be recommended for the treatment of osteomyelitis.

Void filling of tibia compression fracture zones using a novel resorbable nanocrystalline hydroxyapatite paste in combination with a hydroxyapatite ceramic core: first clinical results

INTRODUCTION

It is a generally accepted standard surgical practice to fill-in the metaphyseal defect zones resulting from the reduction of tibia compression fractures. The development of various innovative bone substitutes is also currently on the increase.

MATERIALS AND METHODS

In our prospective study, we used Ostim, a novel resorbable nanocrystalline hydroxyapatite paste, together with Cerabone, a solid hydroxyapatite ceramic, in combination with angularly stable osteosynthesis to treat 24 tibia compression fractures. Types B2 and B3, as well as types C2 and C3 fractures, according to the AO classification, were included in the study.

RESULTS

The mean total range of joint motion in terms of flexion and extension was improved from the immediate postoperative value of 79 +/- 14 degrees to 97 +/- 13 degrees at 6 weeks after surgery, to 109 +/- 16 degrees at 3 months, and finally to 118 +/- 17 degrees at 1 year. In three patients, a delayed wound healing was observed as a local complication.

CONCLUSION

The use of the Ostim and Cerabone combination is an effective method in treating tibia compression fractures with large defect zones left after reduction.

The use of nanocrystalline hydroxyapatite for the reconstruction of calcaneal fractures: Preliminary results

The purpose of this investigation was to evaluate the feasibility of a nanocrystalline hydroxyapatite compound in the treatment of calcaneal fractures with osseous defects after reduction. The study included 21 patients, representing 24 closed intraarticular calcaneus fractures with large defects remaining after operative reduction. All cases were supplemented with the hydroxyapatite bone substitute and stabilized with a calcaneal honeycomb plate. Radiographs were taken at 6 weeks, 12 weeks, 6 months, and 1 year postoperatively, with specific attention given to measurement of Gissane's angle, Böhler's angle, and calcaneal height. A postoperative subjective and objective evaluation of the fracture, using the Creighton Nebraska Health Foundation scale, was performed 1 year postoperatively. Böhler's angle improved from a mean 8.6 +/- 5.3 degrees preoperatively to an immediate postoperative mean result of 31.5 +/- 6.5 degrees and 27.7 +/- 8.6 1 year postoperatively. The mean Creighton-Nebraska functional score was 86 +/- 10 at the 1-year follow-up evaluation. These results suggest that open reduction with plate fixation combined with nanocrystalline hydroxyapatite augmentation presents a good and reliable surgical technique for treatment of calcaneus fractures.

The effect of demineralized bone matrix-calcium sulfate with vancomycin on calcaneal fracture healing and infection rates: a prospective study

BACKGROUND

Displaced intra-articular calcaneal fractures may have a central cancellous bone defect area. We hypothesized that human demineralized bone matrix (DBM) calcium sulfate (CaSO(4)) might act as a reasonable alternative to autograft in calcaneal fractures. When combined with antibiotic powder, this bone graft substitute also may act as a local antibiotic delivery device. This is the first clinical study evaluating bone healing and complications associated with DBM-calcium sulfate bone graft substitute in the treatment of displaced intra-articular calcaneal fractures with a central cancellous bone defect.

METHODS

Over a 29-month period, 33 displaced intra-articular calcaneal fractures with central cancellous defects were treated with open reduction and internal fixation (ORIF) and grafting with vancomycin/DBM-calcium sulfate bone graft substitute. Eleven fractures without bone defects were treated with ORIF only. Patient demographics, medical history, and CT fracture classification were recorded. Postoperatively, fractures were monitored every 2 weeks for healing and complications.

RESULTS

The mean time to union was 8.2 weeks in the grafted, while the control group mean time to union was 10.4 weeks (p = 0.0117). Wound problems occurred in five (15%) of the 33 patients with grafting, all in type III fractures with severe soft-tissue swelling, and included two minor wound healing delays, and three serious wound problems. At a mean followup time of 22.4 months, no DBM-calcium sulfate grafted calcaneus demonstrated evidence of osteomyelitis.

CONCLUSIONS

This is the first study examining human DBM-calcium sulfate bone graft substitute to treat displaced intra-articular calcaneal fractures. Based on these initial data, human DBM-calcium sulfate acted as an acceptable and safe autograft alternative in displaced intra-articular calcaneal fractures with moderate (5 cc to 10 cc) central cancellous bone defects.

Suitability of Calcium Phosphate Cement for Injection Laryngoplasty in Rabbits

Calcium phosphate cement (CPC) consists of powder and liquid, which become an injectable paste after mixing, self-hardening and recrystallizing to calcium hydroxylapatite (CaHA) after injection into a living body. In this study, we investigated the suitability of CPC as an injectable material for injection laryngoplasty using rabbits. All rabbits underwent left recurrent laryngeal nerve section and injection laryngoplasty with CPC. At 7 days, scanning electron microscopic findings revealed that complete recrystallization from CPC to CaHA was achieved in the larynx. At 1, 3, and 6 months, injected CPC stayed in the paraglottic space and did not migrate, and the average remaining CPC volume percentage was 91.7%. Focal foreign body reaction to injected CPC was almost the same as that of autologous fat for all time periods observed. These results indicated that CPC appears to be biocompatible, nonabsorbable, nonmigratory, and suitable for injection laryngoplasty.

Fabrication of Biporous Low-crystalline Apatite Based on Mannitol Dissolution from Apatite Cement

Biporous (macro- and microporous) calcium phosphate gains much attention as a bone substitute material because of its large surface area and that it improves cell penetration. In the present study, we evaluated the feasibility of biporous, low-crystalline apatite based on dissolution of mannitol from self-setting apatite cement (Biopex). Mannitol--known as a biocompatible, easily dissolved monosaccharide alcohol--was recrystallized to obtain larger crystals. It was crushed with pestle and mortar, sieved to obtain crystals which passed through a 500-microm mesh but which remained against a 300-microm mesh, and then used as porogen. Although Biopex containing 60 wt% mannitol was not able to be taken out of the mold, addition of mannitol caused no initial setting inhibition to Biopex if the amount was 40 wt% or less. Similarly, transformation to apatitic product was confirmed when the apatite cement was immersed in 0.9% saline kept at 37 degrees C for seven days. The set mass became low-crystalline, biporous apatite with approximately 60% porosity.

Calcium phosphate cement in musculoskeletal tumor surgery

BACKGROUND AND OBJECTIVES

Calcium phosphate cement (CPC) is an injectable biocompatible bone substitute that has been used for various applications in orthopedic surgery. However, no extensive clinical studies of the use of CPC to fill bone cavities after curettage of musculoskeletal tumors have been reported. The present study reviewed the results for 56 musculoskeletal tumors treated by curettage and CPC implantation.

METHODS

Assessment was based on clinical examination and radiographic findings. Variables for clinical assessment included pain, limb function, and complications. Median follow-up was 18.5 months (range 6-47 months).

RESULTS

One patient experienced post-operative fractures. Three patients displayed local recurrence. One patient developed post-operative superficial wound infection, and two patients with large bony defect exhibited non-infectious serous discharge. No serious adverse effects such as deep venous thrombosis, pulmonary embolism were encountered. In all cases, CPC was radiographically well adapted to the surrounding host bone as of final follow-up.

CONCLUSIONS

CPC appears to offer a useful bone substitute for the treatment of musculoskeletal tumors. As the follow-up period for this study was short, further long-term follow-up studies are needed.

Long-term complications of distal radius bone grafts

PURPOSE

To assess long-term results and complications of cancellous bone graft taken from the distal radius.

METHODS

A total of 1670 cases of bone graft taken from the distal radius for various indications were reviewed retrospectively. The patients were evaluated for success of bone grafting and for the following complications: fracture through donor site, local infection, DeQuervain's tenosynovitis, and neuroma of the superficial radial nerve.

RESULTS

The overall complication rate including bone graft failure within a mean follow-up period of 4.5 years was 4%. Bone graft failure required regrafting with iliac bone in 38 patients (2.3%). DeQuervain's tenosynovitis was noted in 21 patients (1.3%), local soft-tissue infection was noted in 3 patients (0.2)%, fracture through donor site was noted in 2 patients (0.1%), and superficial radial nerve neuromas were noted in 2 patients (0.1%). There were no cases of osteomyelitis.

CONCLUSIONS

Bone grafting from the distal radius is effective with minimal complications and is a practical adjunct to reconstructive hand procedures.