Injectable bone cement augmentation for the treatment of distal radius fractures: a review

An artificial bone filling material of poly l-lactic acid/collagen/nano-hydroxyapatite microspheres: Preparation and collagen regulation on the property

Artificial bone materials are in great need due to a lot of bone injuries. Herein, collagen/nano-hydroxyapatite (Col/nHA, C-H) composite nanospheres were obtained by in-situ mineralization, and poly L-lactic acid/collagen/nano-hydroxyapatite (PLLA/Col/nHA, P-C-H) was further prepared by high-speed shear emulsification method. The interfacial properties and structure between PLLA and nHA are regulated by the adhesive property of Col. The morphology, structure and properties of P-C-H microsphere were characterized in detail by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) and simulated degradation of PBS in vitro. The results show that C-H is uniformly distributed in P-C-H microspheres, and a mesoporous material with a "pomegranate" structure and a particle size of 5-30 μm is self-assembled based on C-H multiple composite microspheres. It is beneficial to the sustained-release degradation of P-C-H and the retention/release of Ca²⁺. The 60-day PBS degradation shows that PLLA delays the degradation of nHA, making the degradation rate of P-C-H basically consist with the human bone healing cycle. The co-culture of P-C-H with MC3T3-E1 cells shows that P-C-H has high biocompatibility and no cytotoxicity. The cell viability is higher than 100 % in 72 h, indicating P-C-H has a proliferation effect on cell growth. Alkaline phosphatase and quantitative real-time PCR test show a positive promotion of P-C-H in cell proliferation and differentiation. The multi-layered P-C-H microspheres have an application potential in bone tissue engineering.

Cement distribution and initial fixability of trochanteric fixation nail advanced (TFNA) helical blades

INTRODUCTION

Early fixation and rehabilitation is the gold standard treatment for intertrochanteric femur fractures. To avoid postoperative complications such as cut-out or cut-through, cement augmentation with perforated helical blades has been developed. The purpose of this study was to evaluate the distribution of injected cement at the head-neck portion of proximal femur using computed tomography (CT) and to examine its initial fixability and clinical outcomes.

PATIENTS AND METHODS

Elderly patients who had intertrochanteric fractures were treated with a helical blade only (BO group) or with a helical blade and cement augmentation (CA group). After fracture reduction, trochanteric fixation nail advanced (TFNA) helical blades were inserted, aiming at the center/center position with 20 mm of tip-apex distance. In the CA group, 4.2 mL of cement was injected under an image intensifier (1.8 mL of cement was directed cranially and 0.8 mL each was directed to the caudally, anteriorly, and posteriorly). Patient demographics, radiographic parameters with CT, and post-operative clinical outcome were examined.

RESULTS

Each group included nine patients with similar demographics. Maximum penetration depth (MPD) in the CA group was significantly greater than those in the BO group for all four directions (p < 0.01). In the CA group, the anterior MPD was significantly greater than the posterior (p < 0.01) and the cranial (p = 0.02) MPD. Surface area and volume in the CA group were two-times and three-times larger than that in the BO group, respectively. Among radiographic parameters, ΔRotation angle in the CA group was significantly smaller than that of the BO group (p = 0.03). For the ΔParker score, the CA group showed less of a decrease than in the BO group (p < 0.01). Visual analog scale (VAS) for the passive range of motion (ROM) and for full-load walking in the CA group was significantly lower than those in the BO group (p < 0.01).

CONCLUSIONS

The initial fixability of the TFNA helical blade with cement augmentation demonstrated double the surface area and triple the volume. This suppressed implant micro-motion, reduced postoperative pain, and accelerated rehabilitation in the acute phase.

Injectable bone cement with magnesium-containing microspheres enhances osteogenesis via anti-inflammatory immunoregulation

Injectable bone cement is especially useful in minimally invasive surgeries to repair small and irregular bone defects. Amongst different kinds of injectable bone cements, bioactive calcium phosphate bone cement (CPC) has been widely studied due to its biological activity. However, its dense structure and poor biodegradability prevent the ingrowth of living tissue, which leads to undesirable bone regeneration and clinical translation. To address this issue, we prepared bone cement based on Magnesium-containing microspheres (MMSs) that can not only be cured into a 3D porous scaffold but also have controllable biodegradability that continuously provides space for desired tissue ingrowth. Interestingly, magnesium ions released from MMSs cement (MMSC) trigger positive immunomodulation via upregulation of the anti-inflammatory genes IL-10 and M2 macrophage polarization with increased expression of CD206, which is beneficial to osteogenesis. Moreover, the physicochemical properties of MMSC, including heat release, rheology and setting time, can be tuned to meet the requirements of injectable bone cement for clinical application. Using a rat model, we have demonstrated that MMSC promoted osteogenesis via mediation of tissue ingrowth and anti-inflammatory immunomodulation. The study provides a paradigm for the design and preparation of injectable bone cements with 3D porous structures, biodegradability and anti-inflammatory immunoregulation to efficiently promote osteogenesis.

A review of calcium phosphate cements and acrylic bone cements as injectable materials for bone repair and implant fixation

Treatment of bone defects caused by trauma or disease is a major burden on human healthcare systems. Although autologous bone grafts are considered as the gold standard, they are limited in availability and are associated with post-operative complications. Minimally invasive alternatives using injectable bone cements are currently used in certain clinical procedures, such as vertebroplasty and balloon kyphoplasty. Nevertheless, given the high incidence of fractures and pathologies that result in bone voids, there is an unmet need for injectable materials with desired properties for minimally invasive procedures. This paper provides an overview of the most common injectable bone cement materials for clinical use. The emphasis has been placed on calcium phosphate cements and acrylic bone cements, while enabling the readers to compare the opportunities and challenges for these two classes of bone cements. This paper also briefly reviews antibiotic-loaded bone cements used in bone repair and implant fixation, including their efficacy and cost for healthcare systems. A summary of the current challenges and recommendations for future directions has been brought in the concluding section of this paper.

A systematic review of the quality of distal radius systematic reviews: Methodology and reporting assessment

Background

Many systematic reviews (SRs) have been published about the various treatments for distal radius fractures (DRF). The heterogeneity of SRs results may come from the misuse of SR methods, and literature overviews have demonstrated that SRs should be considered with caution as they may not always be synonymous with high-quality standards. Our objective is to evaluate the quality of published SRs on the treatment of DRF through these tools.

Methods

The methods utilized in this review were previously published in the PROSPERO database. We considered SRs of surgical and nonsurgical interventions for acute DRF in adults. A comprehensive search strategy was performed in the MEDLINE database (inception to May 2017) and we manually searched the grey literature for non-indexed research. Data were independently extracted by two authors. We assessed SR internal validity and reporting using AMSTAR (Assessing the Methodological Quality of Systematic Reviews and PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyzes). Scores were calculated as the sum of reported items. We also extracted article characteristics and provided Spearman’s correlation measurements.

Results

Forty-one articles fulfilled the eligibility criteria. The mean score for PRISMA was 15.90 (CI 95%, 13.9–17.89) and AMSTAR was 6.48 (CI 95% 5.72–7.23). SRs that considered only RCTs had better AMSTAR [7.56 (2.1) vs. 5.62 (2.3); p = 0.014] and PRISMA scores [18.61 (5.22) vs. 13.93 (6.47), p = 0.027]. The presence of meta-analysis on the SRs altered PRISMA scores [19.17 (4.75) vs. 10.21 (4.51), p = 0.001] and AMSTAR scores [7.68 (1.9) vs. 4.39 (1.66), p = 0.001]. Journal impact factor or declaration of conflict of interest did not change PRISMA and AMSTAR scores. We found substantial inter observer agreement for PRISMA (0.82, 95% CI 0.62–0.94; p = 0.01) and AMSTAR (0.65, 95% CI 0.43–0.81; p = 0.01), and moderate correlation between PRISMA and AMSTAR scores (0.83, 95% CI 0.62–0.92; p = 0.01).

Conclusions

DRF RCT-only SRs have better PRISMA and AMSTAR scores. These tools have substantial inter-observer agreement and moderate inter-tool correlation. We exposed the current research panorama and pointed out some factors that can contribute to improvements on the topic.

Orthobiologics in the augmentation of osteoporotic fractures

Many orthobiologic adjuvants are available and widely utilized for general skeletal restoration. Their use for the specific task of osteoporotic fracture augmentation is less well recognized. Common conductive materials are reviewed for their value in this patient population including the large group of allograft adjuvants categorically known as the demineralized bone matrices (DBMs). Another large group of alloplastic materials is also examined-the calcium phosphate and sulfate ceramics. Both of these materials, when used for the proper indications, demonstrate efficacy for these patients. The inductive properties of bone morphogenic proteins (BMPs) and platelet concentrates show no clear advantages for this group of patients. Systemic agents including bisphosphonates, receptor activator of nuclear factor κβ ligand (RANKL) inhibitors, and parathyroid hormone augmentation all demonstrate positive effects with this fracture cohort. Newer modalities, such as trace ion bioceramic augmentation, are also reviewed for their positive effects on osteoporotic fracture healing.

The use of bone cement in difficult distal radius fractures

BACKGROUND

The lack of structural support remains a challenge in the treatment of comminuted distal radius fractures. Calcium phosphate and calcium sulfate bone cement has been used in other fracture locations in addition to fixation and has been shown to allow for retention of reduction in difficult cases.

METHODS

A case-control retrospective review of 34 consecutive distal radius fractures treated with surgery was performed with the patients classified by Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification. Complications and postoperative radiographs were evaluated.

RESULTS

Cement was used in the most difficult cases. Radial height was retained in both groups. Volar tilt was significantly better in the cement group. There were no significant differences between the case and control groups for any complication. No complications related to the use of the cement were found.

CONCLUSIONS

The use of bone cement as an adjunct to fixation of distal radius fractures seems to include minimal risks and may afford a technical advantage in maintaining reduction during surgery for difficult fractures. Since there is an aspect of fracture difficulty that we cannot control for by using radiographic assessment alone, cement may provide an advantage over fixation without cement, despite similar outcomes. Bone cement can be part of the "tool box" for difficult distal radius fractures. Further study is necessary to define the technical advantages and limitations of each particular cement product.

RADIOLOGICAL ASSESSMENTS OF INJECTED CALCIUM SULFATE BONE CEMENTS IN THE TREATMENT OF DISTAL RADIAL FRACTURE

It has been reported in many literatures that different kinds of bone graft augmentations have been applied in the treatment of distal radial fractures with favorable results. The authors applied calcium sulfate cement in the treatment of distal radial fractures and evaluated the radiological outcomes of 33 patients. The radiological changes of cement statuses, implants, and radiological parameter of distal radius were analyzed. After closed reduction of the displacement, fractures were fixed by Kirschner pins and stabilized by percutaneous injection of premixed calcium sulfate bone cement. Periodic X-ray evaluations were obtained at immediate post-operation and at every month. A total of 28 patients completed the follow-up and the cement extravasations into wrist joint or into soft tissues had been seen in almost every patient. The gradual settling and losses of radial height, radial inclination angle, and volar tilting angles were significant even after removal of Kirschner pins after 8 weeks. Gradual absorptions of cured cement block inside and outside distal radial cortices were observed in every case and complete absorptions of intraosseous cements after 8 weeks happened in 53.6% (15/28) of patients. The extravasated cements took longer time to fade away. The radiological results of current study revealed negative results of calcium sulfate applied in the treatment of distal radial fracture in terms of reduction parameters and cement block longevity.

Antibiotic impregnated cement spacer for salvage of diabetic osteomyelitis

BACKGROUND

Florid infection and osteomyelitis of the forefoot in patients with diabetic neuropathy often requires minor amputation, with risk of subsequent reulceration, reamputation, and patient dissatisfaction. We investigated use of an antibiotic-impregnated cement spacer (ACS) to release antibiotic locally to resolve residual infection and to fill the cavity created by debridement.

METHODS

We report 23 cases of osteomyelitis and associated severe infection of forefoot joints in 20 consecutive patients, age 60.3 +/- 13.4 years. Antibiotic-impregnated cement, extensive meticulous debridement, and ACS placement to fill the gap were employed in all cases. Deep cultures were taken routinely. Fixation with Kirschner wires was used as necessary. Mean followup was 21.2 +/- 10.2 months. A successful result was resolution of infection and wound healing to full skin closure without amputation.

RESULTS

Of 23 cases, 21 (91.3%) healed and two required toe amputation. ACS was left permanently in 10 patients, removed with arthrodesis in six, and removed without arthrodesis in five. One patient recovered but subsequently underwent transtibial amputation due to infection of a different site.

CONCLUSION

Severe infection associated with osteomyelitis of the foot in diabetic patients was successfully treated with extensive debridement and use of ACS, which filled the void created by debridement. Amputation was avoided in most patients. This procedure allowed extensive debridement through filling large voids with ACS, with prolonged antibiotic release.