Autogenous bone graft: donor sites and techniques

Composite bone graft of CaO-MgO-SiO2 glass-ceramics and CaSO4 ceramics for boosting bone formation rate

This study develops a composite bone graft of CaO-MgO-SiO2 glass-ceramic and CaSO4 [abbreviated as (CMS)3-x(CS)x] via the sponge replication technique with weight fractions of x = 0, 1, 1.5, 2, and 3. The (CMS)1.5(CS)1.5 composite displays a superior degradability and, a suitable compressive strength of ∼3 MPa, and excellent cell proliferation and differentiation. The in vivo rat femur test in the hybrid-pore (CMS)1.5(CS)1.5 composite granules achieves a higher rate of bone formation, which is ∼2.7 times better than that of the commercial HAP/β-TCP at 12 weeks. Improved expressions of osteocyte and mature osteocyte marker genes, namely (Spp1, Dmp1, and Fgf23), were observed in the (CMS)1.5(CS)1.5 group, indicating a faster differentiation into mature bone tissue. The ions release of (CMS)1.5(CS)1.5 through the ERK1/2 signaling pathway promotes osteogenic differentiation. The high bone generation rate can be attributed to faster active ions release and modified surface topography. This work highlights an excellent bone graft candidate for clinical applications in orthopedic surgery.

Novel artificial tricalcium phosphate and magnesium composite graft facilitates angiogenesis in bone healing

BACKGROUND

Bone grafting is the standard treatment for critical bone defects, but autologous grafts have limitations like donor site morbidity and limited availability, while commercial artificial grafts may have poor integration with surrounding bone tissue, leading to delayed healing. Magnesium deficiency negatively impacts angiogenesis and bone repair. Therefore, incorporating magnesium into a synthetic biomaterial could provide an excellent bone substitute. This study aims to evaluate the morphological, mechanical, and biological properties of a calcium phosphate cement (CPC) sponge composed of tetracalcium phosphate (TTCP) and monocalcium phosphate monohydrate (MCPM), which could serve as an excellent bone substitute by incorporating magnesium.

METHODS

This study aims to develop biomedical materials composed mainly of TTCP and MCPM powder, magnesium powder, and collagen. The materials were prepared using a wet-stirred mill and freeze-dryer methods. The particle size, composition, and microstructure of the materials were investigated. Finally, the biological properties of these materials, including 3-(4,5-dimethylthiazol-2-yl)-2,5- diphenyltetrazolium bromide (MTT) assay for biocompatibility, effects on bone cell differentiation by alkaline phosphatase (ALP) activity assay and tartrate-resistant acid phosphatase (TRAP) activity assay, and endothelial cell tube formation assay for angiogenesis, were evaluated as well.

RESULTS

The data showed that the sub-micron CPC powder, composed of TTCP/MCPM in a 3.5:1 ratio, had a setting time shorter than 15 minutes and a compressive strength of 4.39±0.96 MPa. This reveals that the sub-micron CPC powder had an adequate setting time and mechanical strength. We found that the sub-micron CPC sponge containing magnesium had better biocompatibility, including increased proliferation and osteogenic induction effects without cytotoxicity. The CPC sponge containing magnesium also promoted angiogenesis.

CONCLUSION

In summary, we introduced a novel CPC sponge, which had a similar property to human bone promoted the biological functions of bone cells, and could serve as a promising material used in bone regeneration for critical bone defects.

Calcium phosphate graphene and Ti3C2Tx MXene scaffolds with osteogenic and antibacterial properties

Bioactive degradable scaffolds that facilitate bone healing while fighting off initial bacterial infection have the potential to change established strategies of dealing with traumatic bone injuries. To achieve this a composite material made from calcium phosphate graphene (CaPG), and MXene was synthesized. CaPG was created by functionalizing graphene oxide with phosphate groups in the presence of CaBr with a Lewis acid catalyst. Through this transformation, Ca2+ and PO4 3- inducerons are released as the material degrades thereby aiding in the process of osteogenesis. The 2D MXene sheets, which have shown to have antibacterial properties, were made by etching the Al from a layered Ti3AlC2 (MAX phase) using HF. The hot-pressed scaffolds made of these materials were designed to combat the possibility of infection during initial surgery and failure of osteogenesis to occur. These two failure modes account for a large percentage of issues that can arise during the treatment of traumatic bone injuries. These scaffolds were able to retain induceron-eluting properties in various weight percentages and bring about osteogenesis with CaPG alone and 2 wt% MXene scaffolds demonstrating increased osteogenic activity as compared to no treatment. Additionally, added MXene provided antibacterial properties that could be seen at as little as 2 wt%. This CaPG and MXene composite provides a possible avenue for developing osteogenic, antibacterial materials for treating bone injuries.

Efficacy and safety of autologous or allogeneic mesenchymal stromal cells from adult adipose tissue expanded and combined with tricalcium phosphate biomaterial for the surgical treatment of atrophic nonunion of long bones: a phase II clinical trial

BACKGROUND

Autologous bone grafting is the standard treatment for the surgical management of atrophic nonunion of long bones. Other solutions, such as bone marrow mesenchymal stem cells (BM-MSC) combined with phospho-calcium material, have also been used. Here we evaluate the safety and early efficacy of a novel procedure using autologous or allogenic adipose tissue mesenchymal stromal cells (AT-MSC) seeded in a patented tricalcium phosphate-based biomaterial for the treatment of bone regeneration in cases of atrophic nonunion.

METHODS

This was a prospective, multicentric, open-label, phase 2 clinical trial of patients with atrophic nonunion of long bones. Biografts of autologous or allogenic AT-MSC combined with a phosphate substrate were manufactured prior to the surgical procedures. The primary efficacy was measured 6 months after surgery, but patients were followed for 12 months after surgery and a further year out of the scope of the study. All adverse events were recorded. This cohort was compared with a historical cohort of 14 cases treated by the same research team with autologous BM-MSC.

RESULTS

A total of 12 patients with atrophic nonunion of long bones were included. The mean (SD) age was 41.2 (12.1) years and 66.7% were men. Bone healing was achieved in 10 of the 12 cases (83%) treated with the AT-MSC biografts, a percentage of healing similar (11 of the 14 cases, 79%) to that achieved in patients treated with autologous BM-MSC. Overall, two adverse events, in the same patient, were considered related to the procedure.

CONCLUSIONS

The results of this study suggest that AT-MSC biografts are safe for the treatment of bone regeneration in cases of atrophic nonunion and reach high healing rates.

TRIAL REGISTRATION

Study registered with EUDRA-CT (2013-000930-37) and ClinicalTrials.gov (NCT02483364).

Clinical Application of Unidirectional Porous Hydroxyapatite to Bone Tumor Surgery and Other Orthopedic Surgery

Unidirectional porous hydroxyapatite (UDPHAp) was developed as a remarkable scaffold characterized by a distinct structure with unidirectional pores oriented in the horizontal direction and connected through interposes. We evaluated the radiographic changes, clinical outcomes, and complications following UDPHAp implantation for the treatment of bone tumors. Excellent bone formation within and around the implant was observed in all patients treated with intralesional resection and UDPHAp implantation for benign bone tumors. The absorption of UDPHAp and remodeling of the bone marrow space was observed in 45% of the patients at a mean of 17 months postoperatively and was significantly more common in younger patients. Preoperative cortical thinning was completely regenerated in 84% of patients at a mean of 10 months postoperatively. No complications related to the implanted UDPHAp were observed. In a pediatric patient with bone sarcoma, when the defect after fibular resection was filled with UDPHAp implants, radiography showed complete resorption of the implant and clear formation of cortex and marrow in the resected part of the fibula. The patient could walk well without crutches and participate in sports activities. UDPHAp is a useful bone graft substitute for the treatment of benign bone tumors, and the use of this material has a low complication rate. We also review and discuss the potential of UDPHAp as a bone graft substitute in the clinical setting of orthopedic surgery.

Analysis of risk factors for the recurrence of osteomyelitis of the limb after treatment with antibiotic-loaded calcium sulfate and autologous bone graft

Objective

We aimed to evaluate the efficacy of antibiotic-loaded calcium sulfate combined with autologous iliac bone transplantation in the treatment of limb-localized osteomyelitis (Cierny-Mader type III) and analyze the causes and risk factors associated with infection recurrence.

Methods

Clinical data of 163 patients with localized osteomyelitis of the extremities treated with antibiotic-loaded calcium sulfate combined with autologous iliac bone transplantation in Xi'an Honghui Hospital from January 2017 to December 2022 were retrospectively analyzed. All patients were diagnosed with localized osteomyelitis through clinical examination and treated with antibiotic-loaded calcium sulfate combined with autologous iliac bone. Based on the infection recurrence status, the patients were divided into the recurrence group and the non-recurrence group. The clinical data of the two groups were compared using univariate analysis. Subsequently, the distinct datasets were included in the binary logistic regression analysis to determine the risk and protective factors.

Results

This study included 163 eligible patients, with an average age of 51.0 years (standard deviation: 14.9). After 12 months of follow-up, 25 patients (15.3%) experienced infection recurrence and were included in the recurrence group; the remaining 138 patients were included in the non-recurrence group. Among the 25 patients with recurrent infection, 20 required reoperation, four received antibiotic treatment alone, and one refused further treatment. Univariate analysis showed that education level, smoking, hypoproteinemia, open injury-related infection, and combined flap surgery were associated with infection recurrence (p < 0.05). Logistic regression analysis showed that open injury-related infection (odds ratio [OR] = 35.698; 95% confidence interval [CI]: 5.997-212.495; p < 0.001) and combined flap surgery (OR = 41.408; 95% CI: 5.806-295.343; p < 0.001) were independent risk factors for infection recurrence. Meanwhile, high education level (OR = 0.009; 95% CI: 0.001-0.061; p < 0.001) was a protective factor for infection recurrence.

Conclusion

Antibiotic-loaded calcium sulfate combined with autologous iliac bone transplantation is an effective method for treating limb-localized osteomyelitis. Patients without previous combined flap surgery and non-open injury-related infections have a relatively low probability of recurrence of infection after treatment with this surgical method. Additionally, patients with a history of smoking and hypoproteinemia should pay attention to preventing the recurrence of infection after operation. Providing additional guidance and support, particularly in patients with lower education levels and compliance, could contribute to the reduction of infection recurrence.

Application of 3D Printing in Cleft Lip and Palate Repair

This manuscript reviews the transformative impact of 3-dimensional (3D) printing technologies in the treatment and management of cleft lip and palate (CLP), highlighting its application across presurgical planning, surgical training, implantable scaffolds, and postoperative care. By integrating patient-specific data through computer-aided design and manufacturing, 3D printing offers tailored solutions that improve surgical outcomes, reduce operation times, and enhance patient care. The review synthesizes current research findings, technical advancements, and clinical applications, illustrating the potential of 3D printing to revolutionize CLP treatment. Further, it discusses the future directions of combining 3D printing with other innovative technologies like artificial intelligence, 4D printing, and in situ bioprinting for more comprehensive care strategies. This paper underscores the necessity for multidisciplinary collaboration and further research to overcome existing challenges and fully utilize the capabilities of 3D printing in CLP repair.

Management of open fracture and related complications: the Japanese way

Open fractures continue to be a challenging clinical problem throughout the world, and Japan is no exception. Surgeons are faced with critical decisions throughout the care of these injuries that can have significant effects in clinical outcome, ranging from the type and timing of antibiotic administration, fixation, soft-tissue management, and interventions for postfracture complications. In October 2022, the Japanese Society for Fracture Repair (JSFR) was invited to represent Japan as the Guest Nation society at the 38th Annual Meeting of the Orthopaedic Trauma Society held in Tampa, Florida. The JSFR organized a symposium, entitled "Management of Open Fracture and related complications-the Japanese way," that featured cutting-edge approaches to open fractures in their country, including presentations on the "fix-and-flap" approach, local antibiotics perfusion delivery, and a "chipping" method for the stimulation of bone healing. This article summarizes the content of these 3 presentations from that symposium.

Morbidity Associated With Distal Tibial Autograft Harvest

Distal tibial autograft harvesting has been studied in the past, but morbidity at the level of the donor site is unclear. The purpose of this retrospective review is to assess morbidity in distal tibial autograft harvesting associated with foot and ankle arthrodesis procedures. A retrospective analysis was performed utilizing patients treated in the last 13 years at a large, multicenter, academic, tertiary referral, research institution. Included patients were between the ages of 18 and 80 years old. One-hundred and seven patients (39 male; 68 female) underwent ipsilateral distal tibial bone graft (n = 110) harvesting to augment the index procedure. Patients were followed for an average of 11.2 months after surgery (Range: 1-73 months). The incidence rate of distal tibial stress fractures was 4.5%, with an overall postoperative complication rate of 8.2%. Overall, low complication rates associated with distal tibial autograft harvesting were found, supporting the use of the distal tibia as an appropriate site for autograft harvesting in foot and ankle surgery.

Effect of structural support size and position on depressed tibial plateau fractures: A finite element analysis

Objective

Structural support for depressed tibial plateau fractures is receiving increasing attention. Currently, there has been little biomechanical evaluation of structural support. This work aimed to investigate the effect of structural support size and position on fracture fixation stability.

Methods

A split-depressed tibial plateau fracture model was created according to the fracture map. Cortical screws combined with structural filler were used for fracture fixation. The filler diameter was set to small, medium and large, and the filler position was set to the center and offset by 1, 2 and 3 mm to study the effect of position and size on stability.

Results

The maximum stress on the implant in all scenarios occurs at the lower contact surface between the anterior screw and the filler. Increased support size resulted in increased mean maximum screw stress, depressed fragment axial displacement and separated fragment transverse displacement (screw stress: 266.6 ± 37.7 MPa vs. 266.7 ± 51.0 MPa vs. 273.8 ± 41.5 MPa; depressed displacement: 0.123 ± 0.036 mm vs. 0.133 ± 0.049 mm vs. 0.158 ± 0.050 mm; separated displacement: 0.402 ± 0.031 mm VS 0.412 ± 0.047 mm VS 0.437 ± 0.049 mm). The larger the offset of the support position was, the larger the peak screw stress and the larger the reduction loss of depressed and separated fragment reduction, regardless of the support size. The medium support combined with the central position presented the minimum of peak stress and reduction loss. Cortical bone was below 2 % and trabecular strain was below 10 % for all scenarios.

Conclusion

Central placement of structural support provides superior stability for the treatment of depressed tibial plateau fractures compared to the eccentric placement. When a support is placed centrally, optimal stability is achieved when the diameter matches the diameter of the depressed region. Thus, the utilization of equal-diameter fillers to provide central support appears to be an ideal selection for depressed tibial plateau fractures.

Evaluation of osteogenic properties of a novel injectable bone-repair material containing strontium in vitro and in vivo

Objective: This study aims to develop and evaluate the biocompatibility and osteogenic potential of a novel injectable strontium-doped hydroxyapatite bone-repair material. Methods: The properties of strontium-doped hydroxyapatite/chitosan (Sr-HA/CS), hydroxyapatite/chitosan (HA/CS) and calcium phosphate/chitosan (CAP/CS) were assessed following their preparation via physical cross-linking and a one-step simplified method. Petri dishes containing Escherichia coli and Staphylococcus epidermidis were inoculated with the material for in vitro investigations. The material was also co-cultured with stem cells derived from human exfoliated deciduous teeth (SHEDs), to assess the morphology and proliferation capability of the SHEDs, Calcein-AM staining and the Cell Counting Kit-8 assay were employed. Osteogenic differentiation of SHEDs was determined using alkaline phosphatase (ALP) staining and Alizarin Red staining. For in vivo studies, Sr-HA/CS was implanted into the muscle pouch of mice and in a rat model of ovariectomy-induced femoral defects. Hematoxylin-eosin (HE) staining was performed to determine the extent of bone formation and defect healing. The formation of new bone was determined using Masson's trichrome staining. The osteogenic mechanism of the material was investigated using Tartrate-resistant acid phosphatase (TRAP) staining and immunohistochemical studies. Results: X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDS) showed that strontium was successfully doped into HA. The Sr-HA/CS material can be uniformly squeezed using a syringe with a 13% swelling rate. Sr-HA/CS had a significant antibacterial effect against both E. coli and S. epidermidis (p < 0.05), with a stronger effect observed against E. coli. The Sr-HA/CS significantly improved cell proliferation and cell viability in vitro studies (p < 0.05). Compared to CAP/CS and CS, Sr-HA/CS generated a substantially greater new bone area during osteoinduction experiments (p < 0.05, p < 0.001). The Sr-HA/CS material demonstrated a significantly higher rate of bone repair in the bone defeat studies compared to the CAP/CS and CS materials (p < 0.01). The OCN-positive area and TRAP-positive cells in Sr-HA/CS were greater than those in control groups (p < 0.05). Conclusion: A novel injectable strontium-doped HA bone-repair material with good antibacterial properties, biocompatibility, and osteoinductivity was successfully prepared.

Adipose-derived mesenchymal stem cells (MSCs) are a superior cell source for bone tissue engineering

Effective bone regeneration through tissue engineering requires a combination of osteogenic progenitors, osteoinductive biofactors and biocompatible scaffold materials. Mesenchymal stem cells (MSCs) represent the most promising seed cells for bone tissue engineering. As multipotent stem cells that can self-renew and differentiate into multiple lineages including bone and fat, MSCs can be isolated from numerous tissues and exhibit varied differentiation potential. To identify an optimal progenitor cell source for bone tissue engineering, we analyzed the proliferative activity and osteogenic potential of four commonly-used mouse MSC sources, including immortalized mouse embryonic fibroblasts (iMEF), immortalized mouse bone marrow stromal stem cells (imBMSC), immortalized mouse calvarial mesenchymal progenitors (iCAL), and immortalized mouse adipose-derived mesenchymal stem cells (iMAD). We found that iMAD exhibited highest osteogenic and adipogenic capabilities upon BMP9 stimulation in vitro, whereas iMAD and iCAL exhibited highest osteogenic capability in BMP9-induced ectopic osteogenesis and critical-sized calvarial defect repair. Transcriptomic analysis revealed that, while each MSC line regulated a distinct set of target genes upon BMP9 stimulation, all MSC lines underwent osteogenic differentiation by regulating osteogenesis-related signaling including Wnt, TGF-β, PI3K/AKT, MAPK, Hippo and JAK-STAT pathways. Collectively, our results demonstrate that adipose-derived MSCs represent optimal progenitor sources for cell-based bone tissue engineering.

A retrospective cohort study of autogenous iliac strut bone grafting in large bone defects of the lower extremity

Autogenous iliac bone graft (AIBG) is the treatment of choice for managing bone defects, and favorable results have been reported for bone defects < 5 cm in length. In large bone defects ≥ 5 cm, it is difficult to obtain good results with simple bone grafting, and other management options have drawbacks, such as long immobilization periods and high complication rates. We hypothesized that AIBG in the strut form might show favorable results in large bone defects with minimal complications. This study aimed to investigate the outcomes of strut-type AIBG and evaluate its effectiveness compared to cancellous AIBG. This retrospective study included 50 patients who underwent AIBG for bone defects at a single institution between March 2011 and April 2020. We performed corticocancellous AIBG in a strut form to manage bone defects ≥ 5 cm in the lower extremities. The strut bone was harvested along the iliac crest and grafted slightly longer than the bone defect to apply a sufficient compressive force. Demographic information and radiographic and clinical results of patients who underwent strut AIBG (Group S) were analyzed. The outcomes of union, time to union, complications, and reoperation were compared with those of patients who underwent cancellous AIBG (Group C). The study population comprised 37 men (74%) and 13 women (26%), with a mean age of 50.0 (range: 19-78). The average follow-up period was 25.6 months (12-104 months). Group S included 16 patients with a mean bone defect length of 6.8 ± 1.2 cm. In Group S, union was achieved in all patients, with an average time to union of 6.7 months. Complications occurred in four cases, all related to wound problems. Group C comprised d 34 patients with a mean defect length of 2.8 ± 1.1 cm. Complications occurred in five patients in Group C, including four soft tissue problems and one implant failure. When comparing the outcomes of Groups S and C, no significant differences were observed. AIBG is an effective and safe technique for managing bone defects. Strut AIBG can be used effectively for bone defects ≥ 5 cm in the lower extremities.

Comparing outcomes of plate augmentation, nail exchange, and nail exchange with plate augmentation in the treatment of atrophic femoral shaft nonunion after intramedullary nailing: a multicenter retrospective study

INTRODUCTION

Intramedullary (IM) nailing is the treatment of choice for femoral shaft fractures, but nonunion rates have been reported to be as high as 12%. Surgical interventions for nonunion involve exchange nailing or plate augmentation. Recently, a combined treatment of exchange nailing and plate augmentation has demonstrated good results, but its comparative effectiveness remains unclear. This study aimed to compare the clinical and radiographic outcomes of three different surgical interventions for atrophic femoral shaft nonunion, and investigate the factors that affect bone healing after reoperation.

MATERIALS AND METHODS

A retrospective study was conducted at five university hospitals involving 149 patients with aseptic atrophic nonunion after IM nailing. These patients underwent reoperation with plate augmentation, exchange nailing, or combined treatment. Clinical and radiographic outcomes were assessed and compared according to reoperation procedure. Logistic regression analysis was performed to identify factors affecting persistent nonunion after reoperation.

RESULTS

Of the cohort, 57 patients underwent plate augmentation, 64 underwent exchange nailing, and 28 received combined treatment. There were no significant differences in patient demographics among the groups. Exchange nailing produced a significantly lower union rate than did the combined treatment (82.8% vs. 100%, p = 0.016), whereas no significant difference was observed in the union rate and time to the union between plate augmentation and the combined treatment. Combined treatment showed the longest operative time and the greatest transfusion requirements. The risk factors for persistent nonunion included age, absence of autogenous bone grafts, and use of an exchange nailing technique.

CONCLUSIONS

Exchange nailing as a treatment for atrophic femoral shaft nonunion after IM nailing resulted in a lower union rate. The efficacy of the combined treatment requires further study, and persistent nonunion may be influenced by age, bone grafting, and surgical techniques. A comprehensive approach targeting both biological environment and mechanical stability is crucial in the treatment of atrophic femoral shaft nonunion.

Autologous Costal Chondral/Osteochondral Transplantation and Costa-Derived Chondrocyte Implantation for Articular Cartilage Repair: Basic Science and Clinical Applications

There has been increasing application of autologous costal chondral/osteochondral transplantation (ACCT/ACOT) and costa-derived chondrocyte implantation (ACCI) for articular cartilage repair over the past three decades. This review presents the major evidence on the properties of costal cartilage and bone and their qualifications as grafts for articular cartilage repair, the major clinical applications, and the risks and strategies for costal chondral/osteochondral graft(s) harvest. First, costal cartilage has many specific properties that help restore the articular surface. Costa, which can provide abundant cartilage and cylindrical corticocancellous bone, preserves permanent chondrocyte and is the largest source of hyaline cartilage. Second, in the past three decades, autologous costal cartilage-derived grafts, including cartilage, osteochondral graft(s), and chondrocyte, have expanded their indications in trauma and orthopaedic therapy from small to large joints, from the upper to lower limbs, and from non-weight-bearing to weight-bearing joints. Third, the rate of donor-site complications of ACCT or ACOT is low, acceptable, and controllable, and some skills and accumulated experience can help reduce the risks of ACCT and ACOT. Costal cartilage-derived autografting is a promising technique and could be an ideal option for articular chondral lesions with or without subchondral cysts. More high-quality clinical studies are urgently needed to help us further understand the clinical value of such technologies.

Arthroscopic Distal Clavicle Bone Bock Combined With Hill-Sachs Remplissage for Primary Anterior Shoulder Instability Treatment

Arthroscopic distal clavicle transfer is an effective option to treat anterior shoulder instability with glenoid bone loss. The use of this free bone graft in an all-inside procedure, with a cortical button fixation makes the construct simpler to perform and allows to be combined with a Hill-Sachs Remplissage to address humeral bone defect. The morbidity of the donor site is low and provide the biologic capacity of an autograft. We report a step-by-step procedure, and the rationale are discussed.

Quantitative Volumetric Measurements of Bone Grafting Sites Within the Lower Extremity on Computed Tomography Scans

The anterior iliac crest is one of the most used options; however, pain and other complications have been reported. Other options for bone harvest in the lower extremity, such as the proximal tibia and calcaneus, can be useful sites for bone grafting. Computed tomography angiography images of the lower extremity were analyzed using 3-D Slicer™ medical imaging software, creating an advanced 3-dimensional model. Bone volume (cm3) and bone mineral density (Hounsfield units) were measured from the cancellous bone in the anterior iliac crest, posterior iliac crest, proximal tibia, and the calcaneus. Fifteen studies were included. The total volume measured it was of 61.88 ± 14.15 cm3, 19.35 ± 4.16 cm3, 32.48 ± 7.49 cm3, 26.40 ± 7.18 cm3, for the proximal tibia, anterior and posterior iliac crest, and calcaneus, respectively. Regarding Hounsfield units, the densities were 116 ± 58.77, 232.4 ± 68.65, 214.4 ± 74.45, 170.5 ± 52.32, for proximal tibia, anterior and posterior iliac crest, and calcaneus. The intraclass correlation coefficients were in average >0.94. In conclusion, the proximal tibia has more cancellous bone than the anterior and posterior iliac crest. The calcaneus has more cancellous bone than the anterior iliac crest. Bone mineral density was highest in the anterior iliac crest and in proximal tibia was the lowest value.

Limitations and modifications in the clinical application of calcium sulfate

Calcium sulfate and calcium sulfate-based biomaterials have been widely used in non-load-bearing bone defects for hundreds of years due to their superior biocompatibility, biodegradability, and non-toxicity. However, lower compressive strength and rapid degradation rate are the main limitations in clinical applications. Excessive absorption causes a sharp increase in sulfate ion and calcium ion concentrations around the bone defect site, resulting in delayed wound healing and hypercalcemia. In addition, the space between calcium sulfate and the host bone, resulting from excessively rapid absorption, has adverse effects on bone healing or fusion techniques. This issue has been recognized and addressed. The lack of sufficient mechanical strength makes it challenging to use calcium sulfate and calcium sulfate-based biomaterials in load-bearing areas. To overcome these defects, the introduction of various inorganic additives, such as calcium carbonate, calcium phosphate, and calcium silicate, into calcium sulfate is an effective measure. Inorganic materials with different physical and chemical properties can greatly improve the properties of calcium sulfate composites. For example, the hydrolysis products of calcium carbonate are alkaline substances that can buffer the acidic environment caused by the degradation of calcium sulfate; calcium phosphate has poor degradation, which can effectively avoid the excessive absorption of calcium sulfate; and calcium silicate can promote the compressive strength and stimulate new bone formation. The purpose of this review is to review the poor properties of calcium sulfate and its complications in clinical application and to explore the effect of various inorganic additives on the physicochemical properties and biological properties of calcium sulfate.

Lamellar Septa-like Structured Carbonate Apatite Scaffolds with Layer-by-Layer Fracture Behavior for Bone Regeneration

Generally, ceramics are brittle, and porosity is inversely correlated with strength, which is one of the challenges of ceramic scaffolds. Here, we demonstrate that lamellar septum-like carbonate apatite scaffolds have the potential to overcome these challenges. They were fabricated by exploiting the cellular structure of the cuttlebone, removing the organic components from the cuttlebone, and performing hydrothermal treatment. Scanning electron microscopy revealed that the scaffolds had a cellular structure with walls between lamellar septa. The interwall and interseptal sizes were 80-180 and 300-500 μm, respectively. The size of the region enclosed by the walls and septa coincided with the macropore size detected by mercury intrusion porosimetry. Although the scaffold porosity was extremely high (93.2%), the scaffold could be handled without disintegration. The compressive stress-strain curve demonstrated that the scaffolds showed layer-by-layer fracture behavior, which seemed beneficial for avoiding catastrophic failure under impact. When the scaffolds were implanted into rabbit femurs, new bone and blood vessels formed within the scaffold cells at 4 weeks. At 12 weeks, the scaffolds were almost entirely replaced with new bone. Thus, the lamellar septum-like cellular-structured carbonate apatite is a promising scaffold for achieving early bone regeneration and compression resistance.

Controlled pore anisotropy in chitosan-gelatin cryogels for use in bone tissue engineering

In tissue engineering, the development of an appropriate scaffold is crucial to provide a framework for new tissue growth. The use of cryogels as scaffolds shows promise due to their macroporous structure, but the pore size, distribution, and interconnectivity is highly variable depending on the fabrication process. The objective of the current research is to provide a technique for controlled anisotropy in chitosan-gelatin cryogels to develop scaffolds for bone tissue engineering application. A mold was developed using additive manufacturing to be used during the freezing process in order to fabricate cryogels with a more interconnected pore structure. The scaffolds were tested to evaluate their porosity, mechanical strength, and to observe cell infiltration through the cryogel. It was found that the use of the mold allowed for the creation of designated pores within the cryogel structure which facilitated cell infiltration to the center of the scaffold without sacrificing mechanical integrity of the structure.

Engineering an injectable gellan gum-based hydrogel with osteogenesis and angiogenesis for bone regeneration

Injectable hydrogels are currently a topic of great interest in bone tissue engineering, which could fill irregular bone defects in a short time and avoid traditional major surgery. Herein, we developed an injectable gellan gum (GG)-based hydrogel for bone defect repair by blending nano-hydroxyapatite (nHA) and magnesium sulfate (MgSO4). In order to acquire an injectable GG-based hydrogel with superior osteogenesis, nHA were blended into GG solution with an optimized proportion. For the aim of endowing this hydrogel capable of angiogenesis, MgSO4 was also incorporated. Physicochemical evaluation revealed that GG-based hydrogel containing 5% nHA (w/v) and 2.5 mM MgSO4 (GG/5%nHA/MgSO4) had appropriate sol-gel transition time, showed a porosity-like structure, and could release magnesium ions for at least 14 days. Rheological studies showed that the GG/5%nHA/MgSO4 hydrogel had a stable structure and repeatable self-healing properties. In-vitro results determined that GG/5%nHA/MgSO4 hydrogel presented superior ability on stimulating bone marrow mesenchymal stem cells (BMSCs) to differentiate into osteogenic linage and human umbilical vein endothelial cells (HUVECs) to generate vascularization. In-vivo, GG/5%nHA/MgSO4 hydrogel was evaluated via a rat cranial defect model, as shown by better new bone formation and more neovascularization invasion. Therefore, the study demonstrated that the new injectable hydrogel, is a favorable bioactive GG-based hydrogel, and provides potential strategies for robust therapeutic interventions to improve the repair of bone defect.

Distinct Cell-Intrinsic Functional Differences Between Iliac Crest and Distal Radius Autografts

PURPOSE

Autologous bone grafts demonstrate osteoconductive, osteoinductive, and osteogenic properties. Hand surgeons commonly augment surgical fixation with autografts to promote fracture healing. This study compared the intrinsic stem cell-like properties of 2 commonly used autograft sources in hand surgery: the iliac crest and distal radius.

METHODS

A total of 9 subjects who received an iliac crest bone graft and distal radius bone graft harvest as a part of the standard care of distal radius malunion or nonunion correction or scaphoid nonunion open reduction and internal fixation were enrolled in the study. Cells were isolated by serial collagenase digestion and subjected to fibroblast colony-forming units, osteogenesis, and adipogenesis assays. The expression levels of genes involved in osteogenesis and adipogenesis were confirmed using quantitative polymerase chain reaction.

RESULTS

The cells isolated from the iliac crest bone graft compared with those isolated from the distal radius bone graft demonstrated significantly higher mean fibroblast colony-forming unit efficiency; increased osteogenesis, as measured using alizarin red quantification; increased adipogenesis, as measured using oil red O quantification; and higher expression levels of genes involved in osteogenesis and adipogenesis under the respective differentiation conditions.

CONCLUSIONS

The cells isolated from the iliac crest bone graft demonstrated a higher fibroblast colony-forming unit capacity and an increased capability to undergo both osteogenesis and adipogenesis.

CLINICAL RELEVANCE

Limited evidence exists comparing the intrinsic stem cell-like properties of the iliac crest and distal radius despite the widespread use of each source in hand and wrist surgery. The information from this investigation may assist hand and wrist surgeons with the selection of a source of autograft.

Comparison of corticocancellous bone graft from the anterolateral metaphysis of the distal radius versus iliac crest for the treatment of unstable scaphoid nonunion with humpback deformity

BACKGROUND

Corticocancellous bone grafting from the iliac crest is acceptable treatment for unstable scaphoid nonunion with a viable proximal pole. However, harvesting graft from the iliac crest is associated with donor site morbidity and the requirement of general anesthesia. Thus, bone grafting from the anterolateral metaphysis of the distal radius (DR) can be a treatment option. However, no study has compared the clinical effect between the two grafting techniques.

METHODS

From 2014 to 2019, patients with unstable scaphoid nonunion with humpback deformity underwent corticocancellous bone grafting from the anterolateral metaphysis of the DR (group DR) or iliac crest (group IC). Humpback deformity was determined by evaluating the scapholunate angle (SLA) ≥ 60°, intrascaphoid angle (ISA) ≥ 45°, and radiolunate angle (RLA) ≥ 15° from preoperative radiographs and computed tomography scans. The SLA, ISA, and RLA served to gauge carpal alignment. The operative time, grip strength, active range of motion (ROM), the Modified Mayo Wrist score (MMWS), and Disabilities of Arm, Shoulder, and Hand (DASH) score were assessed postoperatively.

RESULTS

Thirty-eight patients qualified for the study (group DR, 15; group IC, 23). Union rates did not differ by patient subset (group DR, 100%; group IC, 95.7%; P = .827), and grip strength, ROM, MWS, and DASH score were similar between groups at the last follow-up. The operative time (minutes) was significantly shorter in group DR (median, 98; quartiles, 80, 114) than in group IC (median, 125; quartiles, 105, 150, P < .001). The ISA, RLA, and SLA improved postoperatively in both groups (P < 0.001). The degree of restoring carpal alignment, as evaluated by SLA, showed superior correction capability in group DR (median, 25.3% quartiles, 21.1, 35.3, P < 0.05). Donor site complications were not significantly different between the groups.

CONCLUSIONS

Corticocancellous bone graft from the anterolateral metaphysis of the DR for unstable scaphoid nonunion is associated with a shorter operation time and comparable results with that from the iliac crest in regard to union, restoration of carpal alignment, and wrist function.

LEVEL OF EVIDENCE

Level III.

A novel treatment of clavicular nonunion: Combination with PRP, autologous bone grafting, and internal plate fixation

BACKGROUND

Nonunion is a major concern for orthopedic surgeons, particularly nonunion of the clavicle, which can cause severe pain, loss of full range of motion, poor sleep quality, and loss of strength in the affected individuals. Platelet-rich plasma (PRP), an important biological agent, is widely used in orthopedics.

OBJECTIVE

We used a combination of three techniques - the PRP technique, autologous bone grafting technique, and internal plate fixation technique - to ensure adequate internal fixation and enable a bone growth-supportive environment at the fracture site.

METHODS

The surgical approach was applied to a patient with clavicle nonunion.

RESULTS

Based on postoperative follow-up findings and intraoperative findings at the time of re-removal of the patient's implant, the prognosis at the fracture site was considered satisfactory.

CONCLUSION

We observed that the patient treated with this method had favorable clinical outcomes, and we recommend that this technique be used in patients with long-bone nonunion.

Revisiting Recent Tissue Engineering Technologies in Alveolar Cleft Reconstruction

Tissue engineering and regenerative medicine have received significant attention in treating degenerative disorders and presented unique opportunities for researchers. The latest research on tissue engineering and regenerative medicine to reconstruct the alveolar cleft has been reviewed in this study. Three approaches have been used to reconstruct alveolar cleft: Studies that used only stem cells or biomaterials and studies that reconstructed alveolar defects by tissue engineering using a combination of stem cells and biomaterials. Stem cells, biomaterials, and tissue-engineered constructs have shown promising results in the reconstruction of alveolar defects. However, some contrary issues, including stem cell durability and scaffold stability, were also observed. It seems that more prospective and comprehensive studies should be conducted to fully clarify the exact dimensions of the stem cells and tissue engineering reconstruction method in the therapy of alveolar cleft.

The Pitfalls of Difficult Distal Radius Fractures and Provisional Reduction

Distal radius fractures are some of the most common injuries encountered in orthopedics and require careful consideration when determining the appropriate treatment options. These fractures can be difficult injuries to treat surgically based on a large variability of fracture patterns, bone quality, and anatomy. It is important to understand the potential pitfalls associated with the treatment of difficult distal radius fractures to prevent avoidable complications. Some of these pitfalls include but are not limited to appropriate surgical exposure and soft tissue handling, provisional reduction, fixation type, and augmentation of fracture fixation.

Iliac crest bone graft versus cell-based grafts to augment spinal fusion: a systematic review and meta-analysis

INTRODUCTION

Despite successful fusion rates with iliac crest bone graft (ICBG), donor-site morbidity and increased operating time remain a considerable limitation and drive the search for alternatives. In this systematic review, grafts with additional cellular supplementation were compared with ICBG for spinal arthrodesis. We compared safety, efficacy and long-term outcomes, thus providing the current and relevant evidence for orthopaedic surgeons to make informed choices regarding this rapidly developing field.

METHODS

An electronic literature search was conducted according to the PRISMA guidelines by two independent reviewers for articles published up to 1st March 2023 using PubMed, EMBASE and the Cochrane Central Register of Controlled Trial. Cellular allografts were not included. The following data were extracted: Number of patients, type of graft, fusion assessment method, follow-up duration, fusion rates, clinical outcomes and complications. The methodological quality of evidence (MQOE) was assessed using the Risk of Bias 2 (RoB-2) tool and Risk of Bias In Non-Randomised Studies (ROBINS) tool developed by Cochrane for evaluating bias in randomised and non-randomised studies.

RESULTS

Ten studies fulfiled the inclusion criteria, including 465 patients. The mean number of patients per study was 43.8 (std dev. 28.81, range 12-100). Two studies demonstrated cell-based therapy to be significantly more successful in terms of fusion rates compared to ICBG. However, the remaining eight demonstrated equivocal results. No study found that cell-based therapy was inferior. No difference was seen between the two groups in three studies who focused on degenerative cohorts. No difference in functional outcome scores was seen between the groups. A number of different preparation techniques for cell-based grafts were used throughout the studies.

CONCLUSION

Cell-based therapy offers a promising alternative to ICBG in spinal fusion surgery, which could help reduce the associated morbidity to patients. This review found that cell-based therapy is non-inferior to iliac crest bone graft and may offer patients an alternative treatment option with fewer complications and reduced post-operative pain. However, the literature to date is limited by heterogeneity of the cell preparation and grafting process. Future research with a unified approach to the cell preparation process is required to fully delineate the potential advantages of this technology.

Research progress on the application of magnesium phosphate bone cement in bone defect repair: A review

BACKGROUND

Bone defects arising from diverse causes, such as traffic accidents, contemporary weapon usage, and bone-related disorders, present significant challenges in clinical treatment. Prolonged treatment cycles for bone defects can result in complications, impacting patients' overall quality of life. Efficient and timely repair of bone defects is thus a critical concern in clinical practice.

OBJECTIVE

This study aims to assess the scientific progress and achievements of magnesium phosphate bone cement (MPC) as an artificial bone substitute material. Additionally, the research seeks to explore the future development path and clinical potential of MPC bone cement in addressing challenges associated with bone defects.

METHODS

The study comprehensively reviews MPC's performance, encompassing e.g. mechanical properties, biocompatibility, porosity, adhesion and injectability. Various modifiers are also considered to broaden MPC's applications in bone tissue engineering, emphasizing drug-loading performance and antibacterial capabilities, which meet clinical diversification requirements.

RESULTS

In comparison to alternatives such as autogenous bone transplantation, allograft, polymethyl methacrylate (PMMA), and calcium phosphate cement (CPC), MPC emerges as a promising solution for bone defects. It addresses limitations associated with these alternatives, such as immunological rejection and long-term harm to patients. MPC can control heat release during the curing process, exhibits superior mechanical strength, and has the capacity to stimulate new bone growth.

CONCLUSION

MPC stands out as an artificial bone substitute with appropriate mechanical strength, rapid degradation, non-toxicity, and good biocompatibility, facilitating bone repair and regeneration. Modification agents can enhance its clinical versatility. Future research should delve into its mechanical properties and formulations, expanding clinical applications to create higher-performing and more medically valuable alternatives in bone defect repair.

Three-dimensional radiographic assessment of the mandibular retromolar donor site in different vertical facial growth types

PURPOSE

To assess volumetrically, the impact of vertical facial growth types (VGFT) on the retromolar area as a bone donor site MATERIAL AND METHODS: 60 cone beam computed tomography (CBCT) scans of adult individuals were classified in three groups according to their SN-GoGn angle: hypodivergent group (hG) (33.33%), normodivergent group (NG) (30%) and hyperdivergent group (HG) (36.67%). Total harvestable bone volume and surface (TBV and TBS respectively), total cortical and cancellous bone volume (TCBV and TcBV respectively) and the percentage of cortical and cancellous bone volume (CBV and cBV respectively) were evaluated.

RESULTS

The whole sample showed a mean TBV of 1220.99±448.81mm³ and a mean TBS of 940.29±259.93mm². Statistically significant differences were found between the different outcome variables and the vertical growth patterns (p<0.001). TBS differs for the different vertical growth patterns with the highest mean of TBS observed in the hG group. TBV also significantly differs between the different vertical growth patterns (p<0.001) with the highest mean observed for the hG individuals. Significant differences in percentages of cBV and CBV were present between the hyper-divergent groups and the other groups (p<0.001) with the hyper-divergent group having the lowest percentage of CBV and the highest percentage of cBV.

CONCLUSION

hypodivergent individuals tend to have thicker bone blocks that can be used in onlay technique while thinner bone blocks harvested from hyperdivergent and normodivergent individuals can be used in three-dimensional grafting approach.

Comparative evaluation of multi-fold rib and structural iliac bone grafts in single-segment thoracic and thoracolumbar spinal tuberculosis: clinical and radiological outcomes

OBJECTIVE

To compare clinical and radiological outcomes of multi-fold rib and structural iliac bone grafts, the primary autologous graft techniques in anterolateral-only surgery for single-segment thoracic and thoracolumbar spinal tuberculosis.

METHODS

This retrospective study included 99 patients treated from January 2014 to March 2022, categorized into 64 with multi-fold rib grafts (group A) and 35 with structural iliac bone grafts (group B). Outcomes assessed included hospital stay, operation time, intraoperative blood loss, postoperative drainage, complications, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), the Visual Analog Scale (VAS) for pain, the Oswestry Disability Index (ODI), bone fusion time, and the American Spinal Injury Association (ASIA) impairment scale grade. Segmental kyphotic angle and intervertebral height were measured radiologically before surgery and follow-up.

RESULTS

The mean follow-up was 63.50 ± 26.05 months for group A and 64.97 ± 26.43 months for group B (P > 0.05). All patients had achieved a clinical cure. Group A had a shorter operation time (P = 0.004). Within one week post-surgery, group B reported higher VAS scores (P < 0.0001). Neurological performance and quality of life significantly improved in both groups. No significant differences were observed in segmental kyphotic angle and intervertebral height between the groups pre- and postoperatively (P > 0.05). However, group A showed a greater segmental kyphotic angle at the final follow-up, while group B had better maintenance of kyphotic angle correction and intervertebral height (P < 0.05). Bone fusion was achieved in all patients without differences in fusion time (P > 0.05).

CONCLUSIONS

Multi-fold rib grafts resulted in shorter operation times and less postoperative pain, while structural iliac bone grafts provided better long-term maintenance of spinal alignment and stability, suggesting their use in cases where long-term outcomes are critical.

Biomaterials for Alveolar Ridge Preservation as a Preoperative Procedure for Implant Treatment: History and Current Evidence

In implant treatment, the reduction and structural changes in the alveolar ridge that occur after tooth extraction limit the length, width, and placement position of the implant body, impair esthetics, and, in some cases, make implant placement difficult. To solve these problems, an alveolar ridge preservation (ARP) technique, which is performed simultaneously with tooth extraction, generally aims to promote bone regeneration and prevent alveolar ridge reduction by filling the extraction socket with bone graft material and then covering it with a barrier membrane to protect against the invasion of epithelial tissue. The extraction socket provides a favorable environment for bone regeneration throughout the healing period because the blood supply is abundant, and it effectively retains the bone graft material by using the remaining bone wall of the socket. In recent years, advances in bioengineering technology have led to the development of graft materials with various biological properties, but there is currently no clear consensus regarding the selection of surgical techniques and materials depending on the condition of the alveolar ridge. This review will provide a comprehensive survey of the evidence accumulated to date on ARP, present many cases according to the clinical situation, and discuss various treatment options.

The Efficiency of Highly Porous β-Tricalcium Phosphate With Bone Marrow Aspirate Concentrate in Midfoot Joint Arthrodesis

BACKGROUND

Nonunion is one of the most common and devastating complications following midfoot joint arthrodesis. Many different types of bone grafts and bone substitutes have been used to promote osseous fusion. However, there is no consensus on the gold standard bone grafting material and whether biologic materials should be used alone or in combination. The purpose of this study is to investigate the efficiency of highly porous β-tricalcium phosphate (β-TCP) with bone marrow aspirate concentrate (BMAC) in midfoot joint arthrodesis.

METHODS

This retrospective comparative study included patients who underwent midfoot joint arthrodesis using compression screws. Patients were classified into 2 groups: arthrodesis with highly porous β-TCP and BMAC (group A) and arthrodesis without them (group B). The osseous union rate was compared between the 2 groups. A total of 44 patients (46 feet) including 89 joints were included in this study.

RESULTS

There was a significant difference in the union rate between the 2 groups: 91.5% (43/47 joints) in arthrodesis with highly porous β-TCP and BMAC (group A) and 76.2% (32/42 joints) in arthrodesis without highly porous β-TCP and BMAC (group B; P = .048).

CONCLUSION

This study investigated the efficiency of highly porous β-TCP and BMAC to promote bony healing in midfoot joint arthrodesis. A significantly higher union rate was shown when arthrodesis was performed with highly porous β-TCP and BMAC, compared with arthrodesis performed without them. We suggest that highly porous β-TCP and BMAC can be a viable and effective adjunct to the fixation in midfoot joint arthrodesis.

LEVEL OF EVIDENCE

Level III: Retrospective comparative analysis.

Comparison of two preserved cartilage iliac crest cortical-cancellous bone blocks graft harvesting techniques in children: A prospective, double-blind, randomized clinical trial

PURPOSE

To compare donor-site morbidity for alveolar bone grafting results following cartilage-preserving outer and inner cortico-cancellous iliac crest (OCIC and ICIC) bone block grafting in children.

MATERIALS AND METHODS

Patients were randomly divided into two groups and prospectively reviewed. In the OCIC and ICIC groups, cortico-cancellous bone blocks were harvested at outer and inner iliac crest respectively. Patient characteristics and surgical parameters were compared; pain intensity and duration, lateral femoral cutaneous nerve (LFCN) injury, gait disturbance, scar and contour satisfaction were analysed postoperatively.

RESULTS

Forty-nine consecutive patients (OCIC, 24; ICIC, 25) were included. There were no significant differences in patient characteristics or donor-site surgical parameters. The mean pain score on the first post-operative day was significantly lower in the OCIC group (3.75±1.70) than in the ICIC group (5.20±2.08) (p=0.012). The pain duration was similar in the two groups (median: 5 days). Temporary LFCN injury only occurred in 3 patients in the ICIC group. Postoperatively, the duck and circle gaits were observed in the OCIC and ICIC groups, respectively. There were no significant differences in the claudication duration, scar and contour satisfaction between the groups.

CONCLUSION

OCIC bone graft harvesting is marginally advantageous in children due to less early postoperative donor-site pain and a lower risk of nerve damage.

Malunion of a Clavicle Fracture in a Young Adult: A Case Report and Surgical Intervention

This case study examines the medical complexity of managing a neglected clavicle in a young patient, resulting in a complicated interstitial non-union. Despite initial therapeutic efforts, the fracture was not treated, resulting in significant pain as well as functional and aesthetic disabilities. This case outlines accurate clinical presentation and diagnostic methods. In addition, malunion clavicle fractures require multifaceted therapeutic approaches including surgical interventions, rehabilitation programs, and psychological support. Through comprehensive research and long-term follow-up, this report reveals the complexity of traumatic fractures, highlighting the importance of early recognition and intervention. To address the issue effectively, it is essential to follow a multidisciplinary approach that includes physical assessment, pharmacotherapy, and physiotherapy. This case report aims to highlight the critical role of comprehensive individual care in improving the patient's condition and emphasizes the importance of vigilant healthcare practices.

Anterior and posterior fusion via a posterior and costotransversectomy approach for thoracic spinal tuberculosis: A case report

INTRODUCTION AND IMPORTANCE

Left untreated, spinal tuberculosis can lead to irreversible neurological deficit in patients, lowering quality of life. Combination of antitubercular drugs and surgical approach is important in managing spinal tuberculosis. We report a case of thoracic spinal tuberculosis treated by anterior and posterior fusion via a posterior and costotransversectomy approach.

PRESENTATION OF CASE

A 38 years-old woman diagnosed with paraplegia due to spinal tuberculosis of the thoracic vertebra (Th8) with Frankel A grade for spinal function. Pre-op kyphotic angle was 27.2°. Antitubercular drugs prescribed did not improve paraplegia symptom. Thoracal X-ray and MRI showed pathological fracture on Th8 and paravertebral abscess along anterior corpus of the Th6-9. We performed Sapardan's alternative VI approach that consists of debridement and abscess evacuation, decompression by laminectomy of the Th8, flavectomy and costotransversectomy of the Th8, posterior stabilization of the Th6-7 and Th9-10, and interbody fusion of the Th8. One month postoperative follow up showed improvement on motor function and sensory function. Post op kyphotic angle was 26.7°.

CLINICAL DISCUSSION

Adequate debridement followed by costotransversectomy, interbody fusion and surgical stabilization relieves pain, improves neurologic function, and prevents deformity of spinal tuberculous patient.

CONCLUSION

Although costotransversectomy approach is rarely used in surgical management of spinal TB, it is beneficial in cases with massive abscess involvement since it provides better view to collect and drain massive abscess.

Clavicle Nonunion and Malunion: Surgical Interventions for Functional Improvement

Clavicle nonunion and malunion are relatively uncommon but, when symptomatic, can result in pain and dysfunction that requires surgical intervention. Various reconstructive and grafting techniques are available to achieve stable fixation and union. In the setting of persistent nonunion, vascularized bone grafting may be necessary. A thorough understanding of the patient's type of nonunion and potential for healing is crucial for achieving satisfactory results because is thoughtful preoperative planning and surgical fixation.

"Early Efficacy and Safety of Unilateral Biportal Endoscopic Lumbar Interbody Fusion Versus Minimal Invasive in the Treatment of Lumbar Degenerative Diseases"

STUDY DESIGN

This was a retrospective cohort study.

OBJECTIVE

To compare the early clinical efficacy and radiologic outcomes between unilateral biportal endoscopic lumbar interbody fusion (ULIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF).

SUMMARY OF BACKGROUND DATA

Along with the continuous development of endoscopic technology, the early safety and effectiveness of ULIF technology are still unknown.

MATERIALS AND METHODS

This retrospective study included 61 patients who underwent fusion surgery through ULIF or MIS-TLIF in 2021. Twenty-nine patients underwent ULIF (group A), and 32 underwent MIS-TLIF (group B). Fusion rate, bone graft volume, hidden blood loss (HBL), C-reactive protein level, operative time, Oswestry Disability Index , Visual Analog Scale score, and MacNab criteria were assessed in both groups.

RESULTS

The Visual Analog Scale score for back pain in the early postoperative period was significantly lower in group A than in group B ( P <0.05). All other clinical scores showed improvement, with no significant difference between the 2 groups ( P >0.05). There was no statistically significant difference in postoperative C-reactive protein levels and fusion rates between the 2 groups ( P >0.05). However, HBL was higher and operative time was longer in group A than in group B ( P <0.05). Most importantly, there were no statistically significant differences between groups A and B in fusion rate, length of stay and bone graft volume ( P >0.05). No serious surgical complications occurred in our study.

CONCLUSIONS

ULIF is a new option for lumbar fusion. Despite the drawbacks of longer operation time and higher HBL, ULIF may be a viable alternative to MIS-TLIF as technology advances.

Treatment of an Ulnar Fracture Bone Defect Using Heterotopic Bone Autograft: A Case Report

CASE

Autologous bone grafting has wide applications for the treatment of bony defects. Generally, cancellous or corticocancellous bone grafts are used depending on the characteristics and size of the bony defect and wound bed. The use of heterotopic bone as a potential source of bone graft has not been widely reported. We present a 56-year-old right-hand-dominant male victim of dog mauling who sustained a right ulnar fracture with a 5-cm bony defect, treated with the use of heterotopic bone autograft.

CONCLUSION

Heterotopic bone can be successfully used as an autograft in the treatment of bony defects.

Investigations into the effects of scaffold microstructure on slow-release system with bioactive factors for bone repair

In recent years, bone tissue engineering (BTE) has played an essential role in the repair of bone tissue defects. Although bioactive factors as one component of BTE have great potential to effectively promote cell differentiation and bone regeneration, they are usually not used alone due to their short effective half-lives, high concentrations, etc. The release rate of bioactive factors could be controlled by loading them into scaffolds, and the scaffold microstructure has been shown to significantly influence release rates of bioactive factors. Therefore, this review attempted to investigate how the scaffold microstructure affected the release rate of bioactive factors, in which the variables included pore size, pore shape and porosity. The loading nature and the releasing mechanism of bioactive factors were also summarized. The main conclusions were achieved as follows: i) The pore shapes in the scaffold may have had no apparent effect on the release of bioactive factors but significantly affected mechanical properties of the scaffolds; ii) The pore size of about 400 μm in the scaffold may be more conducive to controlling the release of bioactive factors to promote bone formation; iii) The porosity of scaffolds may be positively correlated with the release rate, and the porosity of 70%-80% may be better to control the release rate. This review indicates that a slow-release system with proper scaffold microstructure control could be a tremendous inspiration for developing new treatment strategies for bone disease. It is anticipated to eventually be developed into clinical applications to tackle treatment-related issues effectively.

Evaluation of a Granular Bone Substitute for Bone Regeneration Using an Optimized In Vivo Alveolar Cleft Model

Alveolar cleft is a common congenital deformity that requires surgical intervention, notably using autologous bone grafts in young children. Bone substitutes, in combination with mesenchymal stem cells (MSCs), have shown promise in the repair of these defects. This study aimed to evaluate the regenerative capabilities of a granular bone substitute using an optimized alveolar cleft model. Thirty-six rats underwent a surgical procedure for the creation of a defect filled with a fragment of silicone. After 5 weeks, the silicone was removed and the biomaterial, with or without Wharton's jelly MSCs, was put into the defect, except for the control group. The rats underwent μCT scans immediately and after 4 and 8 weeks. Analyses showed a statistically significant improvement in bone regeneration in the two treatment groups compared with control at weeks 4 and 8, both for bone volume (94.64% ± 10.71% and 91.33% ± 13.30%, vs. 76.09% ± 7.99%) and mineral density (96.13% ± 24.19% and 93.01% ± 27.04%, vs. 51.64% ± 16.51%), but without having fully healed. This study validates our optimized alveolar cleft model in rats, but further work is needed to allow for the use of this granular bone substitute in the treatment of bone defects.

Direct Integration of 3D Printing and Cryogel Scaffolds for Bone Tissue Engineering

Cryogels, known for their biocompatibility and porous structure, lack mechanical strength, while 3D-printed scaffolds have excellent mechanical properties but limited porosity resolution. By combining a 3D-printed plastic gyroid lattice scaffold with a chitosan-gelatin cryogel scaffold, a scaffold can be created that balances the advantages of both fabrication methods. This study compared the pore diameter, swelling potential, mechanical characteristics, and cellular infiltration capability of combined scaffolds and control cryogels. The incorporation of the 3D-printed lattice demonstrated patient-specific geometry capabilities and significantly improved mechanical strength compared to the control cryogel. The combined scaffolds exhibited similar porosity and relative swelling ratio to the control cryogels. However, they had reduced elasticity, reduced absolute swelling capacity, and are potentially cytotoxic, which may affect their performance. This paper presents a novel approach to combine two scaffold types to retain the advantages of each scaffold type while mitigating their shortcomings.

Enhanced Osteogenesis Potential of MG-63 Cells through Sustained Delivery of VEGF via Liposomal Hydrogel

The challenges of using VEGF to promote osteoblastic differentiation include a short half-life and a narrow therapeutic window. A carrier system combining hydrogel and liposomes may improve the therapeutic efficacy of VEGF for bone regeneration. This study aimed to investigate the effects of delivery of VEGF via liposomal hydrogel on the osteogenesis of MG-63 cells. Liposomal hydrogel scaffold was fabricated and then characterized in terms of the morphological and chemical properties using FESEM and FTIR. In 2.5D analysis, the MG-63 cells were cultured on liposomal hydrogel + VEGF as the test group. The osteogenic effects of VEGF were compared with the control groups, i.e., hydrogel without liposomes + VEGF, osteogenic medium (OM) supplemented with a bolus of VEGF, and OM without VEGF. Cell morphology, viability, and differentiation and mineralization potential were investigated using FESEM, MTT assay, ALP activity, and Alizarin red staining. The characterization of scaffold showed no significant differences in the morphological and chemical properties between hydrogel with and without liposomes (p > 0.05). The final 2.5D culture demonstrated that cell proliferation, differentiation, and mineralization were significantly enhanced in the liposomal hydrogel + VEGF group compared with the control groups (p < 0.05). In conclusion, liposomal hydrogel can be used to deliver VEGF in a sustained manner in order to enhance the osteogenesis of MG-63 cells.

Chitosan nanoparticles for sustained release of metformin and its derived synthetic biopolymer for bone regeneration

Background: There are considerable socioeconomic costs associated with bone defects, making regenerative medicine an increasingly attractive option for treating them. Chitosan is a natural biopolymer; it is used in approaches for sustained slow release and osteogenesis, and metformin has osteoinductivity. Our study aimed to synthesize chitosan and human serum albumin (HSA) with a metformin nanoformulation to evaluate the therapeutic effects of this nanoformulation on bone defects in vitro. Methods: A pluripotent differentiation assay was performed in vitro on mouse bone marrow mesenchymal stem cells (BMSCs). Cell Counting Kit-8 was used to detect whether metformin was toxic to BMSCs. The osteogenesis-related gene expression of osteocalcin (OCN) and osteoprotegerin (OPG) from BMSCs was tested by real-time polymerase chain reaction (PCR). HSA, metformin hydrochloride, and chitosan mixtures were magnetically stirred to finish the assembly of metformin/HSA/chitosan nanoparticles (MHC NPs). The MHC NPs were characterized using transmission electron microscopy (TEM), dynamic light scattering (DLS), and Fourier transform infrared spectroscopy (FT-IR). To test the expression of OCN and OPG, western blot were used. MHC NPs were evaluated in vitro for their osteoinductivity using alkaline phosphatase (ALP). Results: BMSCs successfully differentiated into osteogenic and adipogenic lineages in vitro. According to real-time PCR, a 50 µM concentration of metformin promoted osteogenesis in BMSCs most effectively by upregulating the osteogenic markers OCN and OPG. The microstructure of MHC NPs was spherical with an average nanosize of 20 ± 4.7 nm and zeta potential of -8.3 mV. A blueshift and redshift were observed in MHC NPs following exposure to wavelengths of 1,600-1,900 and 2,000-3,700 nm, respectively. The encapsulation (%) of metformin was more than 90%. The simulation study showed that MHC NPs have good stability and it could release metformin slowly in vitro at room temperature. Upon treatment with the studied MHC NPs for 3 days, ALP was significantly elevated in BMSCs. In addition, the MHC NPs-treated BMSCs upregulated the expression of OPG and OCN, as shown by real-time PCR and western blot. Conclusion: MHC NPs have a stable metformin release effect and osteogenic ability. Therefore, as a derived synthetic biopolymer, it is expected to play a role in bone tissue regeneration.

Periosteum-derived skeletal stem cells encapsulated in platelet-rich plasma enhance the repair of bone defect

BACKGROUND

Spontaneous restoration of large bone defects remains a challenge under infections, tumors, and crushing conditions. Current stem cell-based therapies for treating bone defects need improvement, because the used stem cells are isolated by a traditional protocol, which is based on their properties of in-vitro plastic adherence and fibroblastic colony formation. The stem cells isolated by the traditional protocol belong to a multicellular type mixture, individual cells vary in proliferative and osteogenic potential. Thus, developing a protocol capable of isolating stem cell subset with higher purity is required and urgent.

AIM

This study aimed to sort a subpopulation of stem cells from periosteum using flow cytometry (named as FC-PSCs), and evaluate the proliferative and osteogenic capacity of FC-PSCs in-vitro, and then establish a new stem cell-based therapies for treating bone defects by delivering the FC-PSCs within platelet-rich plasma (PRP).

METHODS

Mouse periosteum was used to sort FC-PSCs using flow cytometry with CD45-TER119-TIE2-ITGAV+CD90 + 6C3-CD105- markers, or isolate periosteum-derived stem cells with the traditional protocol (TP-PSCs) as control. After evaluating the FC-PSCs proliferation and osteogenic differentiation in-vitro as well as the promotive efficacy of platelet-rich plasma (PRP) on FC-PSCs proliferation and osteogenic differentiation, the FC-PSCs were delivered into the femoral epiphysis bone defect site of a mouse model by platelet-rich plasma (PRP). At postoperative 14 or 28 days, these mice were euthanized for harvest the femur specimens for micro-CT, histological evaluation.

RESULTS

In-vitro results determined that the FC-PSCs showed more capacity for proliferation and osteogenic differentiation compared with the TP-PSCs. In addition, in-vitro results showed the promotive efficacy of PRP on FC-PSCs proliferation and osteogenic differentiation. In-vivo results showed that the FC-PSCs delivered by PRP was able to facilitate the repair of bone defects by stimulating new bone formation and remodeling.

CONCLUSION

FC-PSCs delivered by PRP enhance the repair of bone defects by stimulating new bone formation and remodeling.

Acromion and Distal Clavicle Grafts for Arthroscopic Glenoid Reconstruction

BACKGROUND

We intended to determine if an acromion or distal clavicle bone graft could restore large glenoid defects using two novel, screw-free graft fixation techniques.

METHODS

Twenty-four sawbone shoulder models were divided into four groups (n = 6 per group) according to fixation technique and bone graft: (1) modified buckle-down technique with clavicle graft, (2) modified buckle-down technique with acromion graft, (3) cross-link technique with acromion graft, (4) cross-link technique with clavicle graft. Testing was performed sequentially in (1) intact models, (2) after creation of a 30% by-width glenoid defect and (3) after repair. The shoulder joint was translated anteriorly, and glenohumeral contact pressures and load were measured to quantify the biomechanical stability.

RESULTS

Maximum contact pressures were restored to 42-56% of intact glenoid using acromion and clavicle grafts with novel fixation techniques. Acromion grafts attained higher maximum contact pressures than clavicle grafts in all groups. Peak translational forces increased by 171-368% after all repairs.

CONCLUSIONS

This controlled laboratory study on sawbone models found that both the acromion and distal clavicle are suitable autologous bone graft options for treating large anterior glenoid defects, having appropriate dimensions and contours for reconstructing the glenoid arc. The modified buckle-down and cross-link techniques are two graft fixation techniques that restore stability to the shoulder joint upon repairing a large glenoid defect and are advantageous in being screw-free and simple to execute.

Arthroscopic Remnant Coracoid Autograft for Revision of the Failed Latarjet Procedure With Persistent Glenoid Bone Loss

Recurrence of anterior instability after a Latarjet procedure with persistent glenoid bone loss can be related to coracoid bone block resorption, migration, or malposition. Multiple options are available to address anterior glenoid bone loss, including autograft bone transfers (such as iliac crest graft, distal clavicle autograft) or allografts (distal tibia allograft). Here, we present the use of the remnant coracoid process as an option for consideration in the treatment of glenoid bone loss after failed Latarjet procedure with persistent glenoid bone loss. The remnant coracoid autograft is harvested and transferred inside the glenohumeral joint, through the rotator interval, and fixed using cortical buttons. This arthroscopic procedure includes using 1) glenoid and coracoid drilling guides to optimize graft positioning and making the procedure more reproducible and safer and 2) a suture tensioning device to provide intraoperative graft compression and ensure bone graft healing.

Effects of tracer position on screw placement technique in robot-assisted posterior spine surgery: a case-control study

INTRODUCTION

Robot-assisted spine surgery is increasingly used in clinical work, and the installation of tracers as a key step in robotic surgery has rarely been studied.

OBJECTIVE

To explore the potential effects of tracers on surgical outcomes in robot-assisted posterior spine surgery.

METHODS

We reviewed all patients who underwent robotic-assisted posterior spine surgery at Beijing Shijitan Hospital over a 2-year period from September 2020 to September 2022. Patients were divided into two groups based on the location of the tracer (iliac spine or vertebral spinous process) during robotic surgery and a case-control study was conducted to determine the potential impact of tracer location on the surgical procedure. Data analysis was performed using SPSS.25 statistical software (SPSS Inc., Chicago, Illinois).

RESULTS

A total of 525 pedicle screws placed in 92 robot-assisted surgeries were analyzed. The rate of perfect screw positioning was 94.9% in all patients who underwent robot-assisted spine surgery (498/525). After grouping studies based on the location of tracers, we found there was no significant difference in age, sex, height and body weight between the two groups. The screw accuracy (p < 0.01)was significantly higher in the spinous process group compared to the iliac group (97.5% versus 92.6%), but the operation time (p = 0.09) was longer in comparison.

CONCLUSION

Placing the tracer on the spinous process as opposed to the iliac spine may result in longer procedure duration or increased bleeding, but enhanced satisfaction of screw placement.

Application of Nanocellulose-Based Aerogels in Bone Tissue Engineering: Current Trends and Outlooks

The complex or compromised bone defects caused by osteomyelitis, malignant tumors, metastatic tumors, skeletal abnormalities, and systemic diseases are difficult to be self-repaired, leading to a non-union fracture. With the increasing demands of bone transplantation, more and more attention has been paid to artificial bone substitutes. As biopolymer-based aerogel materials, nanocellulose aerogels have been widely utilized in bone tissue engineering. More importantly, nanocellulose aerogels not only mimic the structure of the extracellular matrix but could also deliver drugs and bioactive molecules to promote tissue healing and growth. Here, we reviewed the most recent literature about nanocellulose-based aerogels, summarized the preparation, modification, composite fabrication, and applications of nanocellulose-based aerogels in bone tissue engineering, as well as giving special focus to the current limitations and future opportunities of nanocellulose aerogels for bone tissue engineering.

Efficacy comparison of vascularized iliac crest bone flap and Ilizarov bone transport in the treatment of traumatic bone defects of the tibia combined with large soft tissue defects

BACKGROUND

Traumatic tibial defect complicated with soft tissue defect is a difficult problem in clinic. Vascularized iliac crest bone flap (VIBF) and Ilizarov bone transport are effective methods to treat tibial defects with limited defect length, which most need to be explored accordingly.

METHODS

In this study, a total of 68 patients with traumatic tibial defect (ranging from 4 to 10 cm) and large soft tissue defect were collected retrospectively. The soft tissue defects were repaired by latissimus dorsal musculocutaneous flap (LD), anterolateral thigh flap (ALTF) or both. Thirty-three cases were treated with vascularized iliac crest bone flap transplantation and 35 cases were treated with Ilizarov bone transport. Intraoperative and postoperative follow-up data (including operation time, blood loss, bone union time, external fixation time, external fixation index, complication rate, reoperation rate, and functional evaluation) were recorded, and comparative analysis was performed.

RESULTS

The median follow-up time was 32 months. Compared with Ilizarov group, the VIBF group exhibited statistically faster bone union time (6.3 ± 1.0 vs. 18.2 ± 3.0 months). Moreover, the VIBF group showed shorter EFT (7.3 ± 1.0 vs. 19.2 ± 3.0 months) and a better EFI (34.8 ± 9.2 vs. 84.2 ± 23.7 days/cm). The excellent and good rate of lower limb appearance evaluation in VIBP group was significantly better than that in Ilizarov group. The complication rate and reoperation rate were significantly higher in Ilizarov group.

CONCLUSION

In summary, compared with Ilizarov bone transport, VIBP has the advantages of faster healing, shorter external fixation time, lower complication and reoperation rate, and better appearance within the limited defect length. Ilizarov bone transport is still preferred when the defect length exceeds the maximum repair length of the iliac flap. The daily handling required by bone transport process is painful.

LEVEL OF EVIDENCE

III, Case-control study.