Tibial Bone Defects Research Articles

Bone healing study of alendronate combined with enoxaparin sodium bone cement in rabbits with bone defects

BackgroundTo observe the effect of enoxaparin sodium-polymethyl methacrylate (ES-PMMA) bone cement supplemented with alendronate (AN) on bone repair of bone defects in New Zealand rabbits.MethodsTwenty-seven New Zealand rabbits were randomly divided into ES/AN, ES-PMMA and PMMA groups, with a total of 27 New Zealand rabbits. The drugs loaded in 40 g bone cement powder were as follows: ES/AN group 8000 AxaIU enoxaparin (ES) and 200 mg alendronate (AN), ES-PMMA group 8000 AxaIU enoxaparin (ES), PMMA group without drugs. A bone defect model with a length of 10 mm and a diameter of 5 mm was made from the left tibia of rabbits, and the prepared bone cement was placed in the tibia defect. At 4 weeks, 8 weeks and 12 weeks after the operation, 3 rabbits in each group were sacrificed, and left tibia samples were collected for histological scoring, HE staining and Masson staining. Bone mineral density and new bone volume were measured by imaging, and the related data were processed by one-way ANOVA and least significance difference (LSD) post hoc test.Results(1) Bone mineral density (BMD, mg/mm3) around the bone defect: at the 4th week, BMD in the ES/AN group was higher than that in the PMMA group; at the 8th week, the BMD in the ES/AN group was significantly higher than that in the other two groups; and at the 12th week, the BMD in the ES/AN group was significantly higher than that in the other two groups. (2) New bone volume (BV, mm3): at the 4th week, BV in the ES/AN group was significantly higher than that in the other two groups, BV in the ES/AN group was significantly higher than that in the other two groups at the 8th and 12th weeks, and BV in the ES-PMMA group was higher than that in the PMMA group. (3) Histological score: at the 4th and 8th weeks, the histological score of the ES/AN group was higher than that of the PMMA group, and at the 12th week, the histological score of the ES/AN group was higher than that of the other two groups. (4) Cortical bone thickness (μm): at the 4th, 8th and 12th weeks, the cortical bone thickness in the ES/AN group was higher than that in the other two groups, and the cortical bone thickness in the ES-PMMA group was higher than that in the PMMA group. (5) The percentage of mature area of new bone in the ES/AN group was higher than that in the other two groups at the 4th week, and at the 8th and 12th weeks, the percentage of mature area of new bone in the ES/AN group and ES-PMMA group was significantly higher than that in the PMMA group.Conclusion(1) Enoxaparin sodium bone cement supplemented with alendronate was superior to enoxaparin sodium bone cement and PMMA bone cement in promoting bone repair of tibial bone defects in New Zealand rabbits. (2) Enoxaparin sodium bone cement is superior to PMMA bone cement in promoting bone repair, showing a certain osteogenic potential.

Treatment of tibial large bone defects: A comparative study of bone transport over an intramedullary nail in combination with antibiotic-impregnated calcium sulphate versus bone transport alone with antibiotic-impregnated calcium sulphate

PurposeTo compare the bone transport over an intramedullary nail in combination with antibiotic-impregnated calcium sulphate versus bone transport alone with antibiotic-impregnated calcium sulphate for the treatment of tibial large bone defects. MethodsA retrospective analysis was conducted by enroling 33 surgically treated patients with tibial large bone defects after the debridement for tibial infection or osteomyelitis who were admitted in Lower Limb Surgery Ward of Traumatic orthopaedic Department, Xi'an Honghui Hospital from January 2018 to January 2021. All the patients were categorized in Group A (transport over intramedullary nail, 12 cases) and Group B (transport alone, 21 cases) based on the surgery strategy. The collected clinical materials and data included gender, age, injury mechanism, smoking habits, comorbidity diseases, initial fracture type (open or close), bone defect size, surgical duration, intraoperative bleeding loss, resorption time of calcium sulphate, bone transport time, external fixation time, external fixation index, weight bearing time, complications and Paley bone and functional criteria. ResultsThirty-three patients were enroled and successfully followed up with an average time of 15.25±4.31 months ranged from 8 to 21 months in Group A and an average time of 17.09±5.64 months ranged from 9 to 31 months in Group B. No significantly statistical differences of the demographic data were discovered between the two groups. There were no significantly statistical differences of the average bone defect size, intraoperative bleeding loss, resorption time of calcium sulphate and bone transport time between the two groups. However, the average surgical duration (P = 0.002) was significantly longer in Group A than Group B and the average external fixation time (P<0.001), external fixation index(P = 0.002) and weight bearing time (P = 0.030) were significantly shorter in Group A than Group B. No significantly statistical difference of excellent and good rate of bone outcomes and complication rate was observed, however, the excellent and good rate of functional outcomes (P = 0.041) was significantly higher in Group A than Group B. ConclusionCompared with the conventional Ilizarov technique combining with antibiotic-impregnated calcium sulphate for large tibial bone defects, bone transport over an intramedullary nail in combination with antibiotic-impregnated calcium sulphate had favourable external fixation time, external fixation index, weight bearing time and clinical functional outcomes which effectively suppressed the infection and allowed patients earlier removal of the external fixator and weight bearing for rehabilitation.

Comparison between Effect of Bisphosphonates, Concentrated Growth Factors or Combination on Rabbits’ Tibial Bone Defects Healing: An Experimental Study

This study was designed to evaluate the effect of bisphosphonates (BIS) or concentrated growth factors (CGF) or a combination of them on bone defect healing. Bone defects of 3-mm width and 6-mm depth were prepared in 24 rabbit tibias unilaterally, then randomly divided into the following four equal groups: 1. Group I: No treatment 2. Group II: Treated by BIS 3. Group III: Treated by CGF 4. Group IV: Treated by BIS + CGF Animals were equally sacrificed at 4 weeks, and at 6 weeks then tibias were processed for hematoxylin and eosin (H&E) and Masson's trichrome (MTC) staining. The data were subjected to one-way analysis of variance (ANOVA) followed by post hoc Tukey test and unpaired Student's t-test. In group IV, the quality of newly formed bone was better than any other group with increased mineralization and decreased collagen, followed by group III, then group I, while group II showed the least favorable results. The statistical analysis showed a significant difference between groups. Mixing BIS with CGF showed the best healing, and bone quality results, followed by CGF-treated group, then control, and finally, BIS-treated group. Using CGF as a scaffold and mixing it with BIS could help accelerate the healing of bone defects, reduce healing time, and minimize the risk of infection.

Pedicled Double-Barrel Fibular Transplantation Versus Bone Transport in the Treatment of Upper Tibial Osteomyelitis with Bone Defects: A Retrospective Study.

This study aimed to compare the clinical effects of using pedicled double-barrel fibular transplantation (PDBFT) and bone transport (BT) for the treatment of upper tibial osteomyelitis with bone defects. A total of 83 patients with upper tibial osteomyelitis and bone defects were selected and retrospectively studied in Xi'an Hong Hui Hospital from January 2009 to January 2019. There were 52 males and 31 females, aged 19-72 years. The tibial defect range was 5-12 cm. Patients were divided into two groups, including the PDBFT (40 cases) and the BT group (43 cases). All patients were classified according to Cierny-Mader classification, including 48 cases of type III and 35 cases of type IV. Operation time, blood loss and cure time were compared. Ennecking score was used to evaluate limb functions, including pain, activity function, self-perception, brace use, walking ability, and gait change, while self-rating anxiety scale (SAS) was used for postoperative mental and psychological status. In addition, complications were recorded. All patients were followed for at least 2 years. SPSS 23.0 software was used to process data. There was no significant difference in demographic data between the two groups (p > 0.05). Operation time was 182.5 ± 22.7min in PDBFT group vs, 124.2 ± 15.6min in BT group, respectively (p < 0.05); intra-operative blood loss was 286 ± 34 ml vs 45 ± 18 ml (p < 0.05); cure time was 7.3 ± 1.8 months vs 11.6 ± 3.7 months (p < 0.05); and Ennecking score was 87.3% and 76.0%, respectively (p < 0.05). So, the PDBFT group showed longer operation time, more blood loss, shorter cure time, and better Ennecking score than the BT group. Importantly, limb functions of the PDBFT group were better than that of the BT group. Moreover, the PDBFT group presented better postoperative mental status and fewer complications than that in BT group (p < 0.05). Patients were successfully cured by both the PDBFT and BT techniques. Compared with the BT group, the PDBFT group brought better clinical effects and fewer complications which could be the first operative choice for the treatment of upper tibial osteomyelitis with bone defects.

Radiological evaluation for effect of NAC on tibia puncture fracture in dogs

The present study used N- acetyl cysteine NAC to study its effects on tibia bone defects in dogs. This study aimed to evaluate the effective use of N- acetylcysteine (NAC) on tibia puncture fracture in dogs. The dogs were divided into three groups (5 dogs for each one): Control group (treated with autogenous cartilage only), treated group 1(treated with autogenous cartilage mixed with NAC), and treated group 2 (treated with autogenous cartilage and NAC orally). Radiological assessment fourteen days postoperatively, there is no evidence of periosteal reaction in the radiological examination in the control group. While the radiological findings revealed evidence of periosteal response at the ridges of the bone gap in treated group one and radiological results showed evidence of more periosteal interaction at the edges of the bone gap in treated group two compared with the group one and control group, and the gap appeared cloudy in color. Twenty-eight days postoperatively showed that the bone gap seemed dark in the shade of bone gap in control groups. Twenty-eight days postoperatively in treated group one, radiographs showed a narrowing in the bone gap diameter as showed by radiological examination.

Collagen membrane from bovine pericardium for treatment of long bone defect.

The treatment of bone regeneration failures has been constantly improved with the study of new biomaterials. Techgraft® is a collagen membrane derived from bovine pericardium, which has been shown to have biocompatibility and effectiveness in tissue repair. However, its use in orthopedics has not yet been evaluated. Therefore, the purpose of this study was to characterize a bovine pericardium collagen membrane and evaluate the effects of its use in the regeneration of a bone defect in rat tibia. Scanning electron microscopy, atomic force microscopy, weight lost and water uptake tests, and mechanical test were performed. Afterwards, the membrane was tested in an experimental study, using 12 male Sprague Dawley rats. A bone defect was surgically made in tibiae of animals, which were assigned to two groups (n=6): bone defect treated with collagen membrane (TG) and bone defect without treatment (CONT). Then, tibiae were submitted to micro-CT. The membranes preserved their natural collagen characteristics, presenting great strength, high water absorption, hydrophilicity, and almost complete dissolution in 30 days. In the experimental study, the membrane enhanced the growth of bone tissue in contact with its surface. A higher bone volume and trabeculae number and less trabecular space was observed in bone defects of the membrane group compared to the control group at 21 days. In conclusion, the Techgraft membrane seems to have favorable characteristics for treatment of long bone repair.

Osteogenic enhancement of modular ceramic nanocomposites impregnated with human dental pulp stem cells: an approach for bone repair and regenerative medicine

Background/aimHuman dental pulp-derived mesenchymal stem cells (hDP-MSCs) are a promising source of progenitor cells for bone tissue engineering. Nanocomposites made of calcium phosphate especially hydroxyapatite (HA) offer an impressive solution for orthopedic and dental implants. The combination of hDP-MSCs and ceramic nanocomposites has a promising therapeutic potential in regenerative medicine. Despite the calcium phosphate hydroxyapatite (HA)-based nanocomposites offer a good solution for orthopedic and dental implants, the heavy load-bearing clinical applications require higher mechanical strength, which is not of the HA’ properties that have low mechanical strength. Herein, the outcomes of using fabricated ceramic nanocomposites of hydroxyapatite/titania/calcium silicate mixed at different ratios (C1, C2, and C3) and impregnated with hDP-MSCs both in in vitro cultures and rabbit model of induced tibial bone defect were investigated. Our aim is to find out a new approach that would largely enhance the osteogenic differentiation of hDP-MSCs and has a therapeutic potential in bone regeneration. Subjects and methodsHuman DP-MSCs were isolated from the dental pulp of the third molar and cultured in vitro. Alizarin Red staining was performed at different time points to assess the osteogenic differentiation. Flow cytometer was used to quantify the expression of hDP-MSCs unique surface markers. Rabbits were used as animal models to evaluate the therapeutic potential of osteogenically differentiated hDP-MSCs impregnated with ceramic nanocomposites of hydroxyapatite/tatiana/calcium silicate (C1, C2, and C3). Histopathological examination and scanning electron microscopy (SEM) were performed to evaluate bone healing potential in the rabbit induced tibial defects three weeks post-transplantation. ResultsThe hDP-MSCs showed high proliferative and osteogenic potential in vitro culture. Their osteogenic differentiation was accelerated by the ceramic nanocomposites’ scaffold and revealed bone defect’s healing in transplanted rabbit groups compared to control groups. Histopathological and SEM analysis of the transplanted hDP-MSCs/ceramic nanocomposites showed the formation of new bone filling in the defect area 3 weeks post-implantation. Accelerate osseointegration and enhancement of the bone-bonding ability of the prepared nanocomposites were also confirmed by SEM. ConclusionsThe results strongly suggested that ceramic nanocomposites of hydroxyapatite/ titania /calcium silicate (C1, C2, and C3) associated with hDP-MSCs have a therapeutic potential in bone healing in a rabbit model. Hence, the combined osteogenic system presented here is recommended for application in bone tissue engineering and regenerative medicine.

Total flavonoids of Rhizoma drynariae promote angiogenesis and osteogenesis in bone defects.

Bone defects are difficult to heal, which conveys a heavy burden to patients' lives and their economy. The total flavonoids of Rhizoma drynariae (TFRD) can promote the osteogenesis of distraction osteogenesis. However, the dose effect is not clear, the treatment period is short, and the quality of bone formation is poor. In our study, we observed the long-term effects and dose effects of TFRD on bone defects, verified the main ingredients of TFRD in combination with network pharmacology for the first time, explored its potential mechanism, and verified these findings. We found that TFRD management for 12 weeks regulated osteogenesis and angiogenesis in rats with 4-mm tibial bone defects through the PI3K/AKT/HIF-1α/VEGF signaling pathway, especially at high doses (135 mg kg-1 d-1 ). The vascularization effect of TFRD in promoting human umbilical vein endothelial cells was inhibited by PI3K inhibitors. These results provide a reference for the clinical application of TFRD.

Clinical efficacy of 3D printed anatomical titanium alloy tibial prosthesis in reconstruction of bone defects in the lower tibia

Clinical efficacy of 3D printed anatomical titanium alloy tibial prosthesis in reconstruction of bone defects in the lower tibia

Outcomes of Patients With Large Versus Small Bone Defects in Open Tibia Fractures Treated With an Intramedullary Nail: A Descriptive Analysis of a Multicenter Retrospective Study.

To compare outcomes in patients with open tibia shaft fractures based on defect size. Retrospective review. Eighteen trauma centers. The study included 132 patients with diaphyseal tibia bone defects >1 cm and ≥50% cortical loss treated with intramedullary nail. The primary outcome was number of secondary surgeries to promote healing (bone graft, revision fixation, or bone transport). Additional outcomes included occurrence of secondary surgeries (bone graft, infection, amputation, and flap failure) and proportion healed at one year. Results are compared by "radiographic apparent bone gap" of <2.5 or ≥2.5 cm. The estimated conditional probability of bone grafting within one year given graft-free at 90 days was 44% and 47% in the <2.5 cm and ≥2.5 cm groups, respectively. An estimated infection risk of 14% was observed in both groups [adjusted hazard ratio (HR) 0.98, 95% confidence interval (CI): 0.33-2.92], estimated amputation risk was 9% (<2.5 cm) and 4% (≥2.5 cm) (unadjusted HR 0.66, 95% CI: 0.13-3.29), and estimated flap failure risk (among those with flaps) was 10% and 13%, respectively (unadjusted HR 1.71, 95% CI: 0.24-12.25). There was no appreciable difference in the proportion healed at one year between defect sizes [adjusted HR: 1.07 (95% CI, 0.63-1.82)]. Larger size bone defects were not associated with higher number of secondary procedures to promote healing or a lower overall one-year healing rate. Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Effect of Annular External Fixator-Assisted Bone Transport on Clinical Healing, Pain Stress and Joint Function of Traumatic Massive Bone Defect of Tibia.

Objective To investigate the effect of annular external fixator-assisted bone transport in the treatment of traumatic massive bone defect of tibia on clinical healing, pain stress, and joint function. Methods From January 2018 to November 2021, 146 patients with traumatic massive bone defect of tibia were selected as the research objects, and they were divided into observation group (annular external fixator-assisted bone transport, 71 cases) and control group (unilateral external fixator bone lengthening, 75 cases) according to different surgical methods. The therapeutic efficacy, fracture healing-related indexes, and postoperative range of motion of the knee joint were compared between the two groups. Callus healing was evaluated by Fernandez-Esteve callus score, and joint function was evaluated by Paley score, American Knee society score (AKSS), and Baird-Jackson ankle score. The changes of pain mediator (serum substance P (SP), neuropeptide Y (NPY), prostaglandin E2 (PGE2), and tumor necrosis factor-α (TNF-α)) and stress indexes (adrenocorticotropic hormone (ACTH), cortisol (COR), and nor Epinephrine (NE)) were observed before and after treatment in two groups. The incidence of postoperative complications was analyzed. Results There were no significant differences in total effective rate and bone lengthening between the two groups (P > 0.05). The bone healing time and callus formation time in the observation group were shorter than those in the control group, and the Fernandez-Esteve callus score was higher than that in the control group (P < 0.05). The levels of SP, NPY, PGE2, TNF-α, ACTH, COR, and NE in the observation group were lower than those in the control group (P < 0.05). AKSS and Baird-Jackson scores in the observation group after operation were higher than those in the control group (P < 0.05). There was no significant difference in the incidence of postoperative complications between the two groups (P > 0.05). Conclusion Annular external fixator-assisted bone transport can promote postoperative fracture healing, reduce pain stress level, and improve joint function of patients with traumatic massive bone defect of tibia.

Effect of Systemic Administration of Granulocyte-Colony Stimulating Factor on Rate of Fracture Healing of Bone Defect in Goats as Animal Model

Granulocyte-colony stimulating factor (G-CSF) serves as an important cytokine in haematopoiesis; released at both physiological and pathological conditions by a range of cells. We hypothesized that the systemic administration of G-CSF would produce an accelerated fracture-healing rate in non-union bone defects; thus, potentially leading to useful clinical applications. Ten male adult Katjang goats, weighing about 15-26 kilograms were randomly chosen and a tibial bone defect was induced in each animal. The defect was maintained by internal fixation with a titanium plate and reinforced by an external fiberglass cast. Post-operative radiographs were performed twice weekly and radiographic assessments were performed by evaluating the bridging and union measurements through a validated method. In the treatment group, the time for bridging and union exhibited statistically significant differences when compared with a control group. The outcomes of the present study establishing a notion that administration of G-CSF besides inducing haematopoiesis, promotes healing of fractures and non-union bone defects as well.

Reconstruction Using an Osteofasciocutaneous Fibula Free Flap for a Distal Tibial Defect in Refractory Chronic Osteomyelitis: A Case Report

The fibular free flap (FFF) is an option used for tibial defect reconstruction in post-traumatic chronic osteomyelitis (PCOM). However, as the tibia is a weight-bearing bone, there exists a risk of compression fracture risk after FFF. This complicates reconstructing distal tibial defects adjacent to the articular cartilage. We report a successful case of reconstruction using FFF for a bone defect adjacent to the distal tibial articular surface in refractory PCOM. The patient was a 73-year-old woman with refractory PCOM in the right distal tibia secondary to a tibial fracture from a traffic accident that occurred 28 years ago. After bone debridement, the tibial bone defect was 8 cm in length, and its distal margin was located 0.5 cm above the articular surface of the tibiotalar joint. Tibial bone and soft tissue defects were reconstructed using a contralateral FFF consisting of an 8-cm fibula bone and a 14×5-cm-sized skin paddle. After 2 months, an Ilizarov apparatus was applied and maintained for 3 months. After 6 months, she started weight-bearing. The follow-up period was 15 months. Imaging studies revealed bone block union. The patient displayed no difficulty in ambulation and had no additional infections or flap necrosis.

3D-printed bi-layered polymer/hydrogel construct for interfacial tissue regeneration in a canine model

ObjectivesThere are complications in applying regenerative strategies at the interface of hard and soft tissues due to the limited designs of constructs that can accommodate different cell types in different sites. The problem originates from the challenges in the adhesion of dissimilar materials, such as polymers and hydrogels, that can be suitable for regenerating different tissues such as bone and soft tissues. This paper presents a design of a new hybrid construct in which a polymer (polycaprolactone (PCL)) membrane firmly adheres to a layer of hydrogen (gelatin). MethodsPCL membranes with defined size and porosity were fabricated using 3D printing. The gelatin layer was attached to the PCL membranes using the aminolysis procedure. We have examined this construct for the application of Guided Bone Regeneration (GBR) as a typical surgical regenerative procedure of the oral cavity at the interface of bone and soft tissue. Complete in vitro and in vivo investigations on canine tibia bone defects have been performed. Histological analyses for fibrosis morphometric and bone morphometric evaluation, as well as bone-fibrosis histological grading and CBCT imaging, were conducted. ResultsChemical and morphological studies of the membrane proved that gelatin was uniformly attached to the aminolyzed PCL membranes. The in vitro and in vivo studies indicated the membrane's biocompatibility, mechanical stability, and barrier function for the GBR application. Furthermore, in vitro study showed that the membranes could improve osteogenesis and the regeneration of bone defects. The results illustrated that the mean bone density in the membrane groups was about three times more than that of the control group. SignificanceThe fabricated 3D-printed hybrid Gelatin/PCL bi-layered membrane can be a good candidate for interfacial tissue engineering and a promising membrane for GBR procedure.

Using allogenous structural bone graft for uncontained tibial bone defects ≥ 10 mm in depth in primary total knee arthroplasty

BackgroundIn primary total knee arthroplasty (TKA), tibial bone defects ≥ 10 mm in depth often become uncontained defects, a condition most surgeons find challenging to treat. Although the allogenous bone graft is a useful method, complications such as infection and nonunion are likely to occur. There are several reports on the use of allogenous bone graft in revision TKA; however, few studies have investigated its use in primary TKA. We performed primary TKA using the allogenous bone graft as a structural bone graft to treat uncontained defects ≥ 10 mm in depth. This study aimed to assess the clinical and radiographical results after primary TKA with allogenous structural bone graft (ASBG).MethodsSeventeen patients (mean age, 69.2 years) with a follow-up period of at least 7 years, were retrospectively reviewed. All cases had been treated for medial bone defects using the ipsilateral medial tibial allogenous bone. Clinical evaluation included the assessment of the knee and function scores and knee angle, and the hip-knee-ankle (HKA) angle, bone union, and radiolucent line (RL) were assessed radiologically.ResultsThe mean depth of the medial tibial defects after tibia cutting was 16.8 mm. Nonunion occurred in one case, and RL occurred in another. We observed a significant difference when the preoperative knee score and HKA angle of patients was compared with that at 1 year postoperatively and the final evaluation. No major complications were observed.ConclusionThe ASBG technique produced favorable surgical outcomes and may be an acceptable procedure for managing uncontained tibial bone defects ≥ 10 mm in depth in primary TKA.

The role of adding Hyaluronic Acid in the grafting process for the repair of experimentally induced tibial defect in dogs model

The study was designed to determine the role of adding hyaluronic acid as a supportive filling material to improve grafting process of experimentally defective tibial bone in dog model. Eighteen local breed dogs of both sexes weighted 18± 0.4 kg and aged (12± 0.6Months) were randomly allocated in two equal groups. In the first group, twelve dogs underwent experimental tibial bone defect (2.5×0.7 cm ) and replaced with deprotenized lamb ribs. The second group were treated as that for the first, but supported by adding 1% hyaluronic acid, to their grafts. The bone in both groups was firmly fixed by cerclage wire. All dogs were; followed-up clinically, radiologically and macroscopically at (14, 30 and 60 days after the intervention. In all study dogs the systemic infections, signs of seromas, hematoma and sever lameness were not developed along the period of the study . Grossly, dogs in the second group at 60 days showed an increase in the size of the filler of bone at the edges and in the mid of the defect, improvement and acceleration in the bone healing, and formation of bone bridges compared to the first group. Radiological finding exhibited complete healing of the fixated bone segment with the surrounding area; however, some cortical irregularities denoted chronic periosteal reaction and callus formation in the treatment with hyaluronic acid. In conclusion, the study indicated that hyaluronic acid with xenograft materials exhibited remarkable beneficial effects on improvement of the tibial bone defect augmentation

Usefulness of Trabecular Metal Cones in Revision Total Knee Arthroplasty in a Korean Population: A Case Series.

PurposeThe purpose of this study was to assess the medium-term results of trabecular metal cones for the reconstruction of large bone defects in revision TKA.MethodsThirteen patients who had undergone revision TKA using trabecular metal cones for femoral and/or tibial large bone defects were identified. We included patients who had a minimum of three years follow-up in the study. We evaluated their functional outcomes, implant survivorship, radiological findings, and complications.ResultsAt a mean follow-up of 6.9 years (range of 3.5–9.4 years), all trabecular metal cones and implants were well fixed and did not exhibit any radiographic evidence of migration or loosening. At the final follow-up, the mean Knee Society knee scores had improved from 37.2 to 78.1 (p < 0.05), and function scores had improved from 35.5 to 77.5 points (p < 0.05). One intraoperative fracture in the distal femur occurred in an 85-year-old woman during impaction of a single trabecular metal cone. The fracture was successfully affixed to the femoral cone and bone three months postoperatively.ConclusionThe present study of trabecular metal cones demonstrates excellent clinical outcomes and survivorship in revision TKA during medium-term follow-up periods. However, longer-term follow-up studies are needed to further investigate these implants in revision TKA. Additionally, the necessity of metal cones in revision procedures should be carefully considered depending on patient needs and economic capabilities.

Bone Defects in Tibia Managed by the Bifocal vs. Trifocal Bone Transport Technique: A Retrospective Comparative Study.

BackgroundThe purpose of this study is to evaluate the clinical effectiveness and determine the differences, if any, between the trifocal bone transport (TFT) technique and the bifocal bone transport (BFT) technique in the reconstruction of long segmental tibial bone defects caused by infection using a monolateral rail external fixator.MethodsA total of 53 consecutive patients with long segmental tibial bone defects caused by infection and treated by monolateral rail external fixator in our department were retrospectively collected and analyzed from the period January 2013 to April 2019, including 39 males and 14 females with an average age of 38.8 ± 12.4 years (range 19–65 years). Out of these, 32 patients were treated by the BFT technique, and the remaining 21 patients were managed by the TFT technique. The demographic data, operation duration (OD), docking time (DT), external fixation time (EFT), and external fixation index (EFI) were documented and analyzed. Difficulties that occur during the treatment were classified according to Paley. The clinical outcomes were evaluated by following the Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria at the last clinical visit.ResultsAll patients achieved an infection-free union finally, and there was no significant difference between the two groups in terms of demographic data and both ASAMI bone and functional scores (p > 0.05). The mean defect size and OD in TFT (9.4 ± 1.5 cm, 161.9 ± 8.9 min) were larger than that in BFT (7.8 ± 1.8 cm, 122.5 ± 11.2 min) (p < 0.05). The mean DT, EFT, and EFI in TFT (65.9 ± 10.8 days, 328.0 ± 57.2 days, 34.8 ± 2.1 days/cm) were all less than those in BFT (96.8 ± 22.6 days, 474.5 ± 103.2 days, 60.8 ± 1.9 days/cm) (p < 0.05). Difficulties and complications were more prevalent in the BFT group than in the TFT group (p < 0.05).ConclusionBoth the trifocal and BFT techniques achieve satisfactory clinical outcomes in the reconstruction of long segmental tibial bone defects caused by infection using a monolateral rail external fixator. The TFT technique can significantly decrease the DT, EFT, EFI, difficulties, and complications compared with the BFT technique.

Modified donor blood flow-preserved cross-leg anterolateral thigh flap procedure for complex lower extremity reconstruction

BackgroundComplex lower limb reconstruction due to severe trauma remains a challenge for reconstructive surgeons. Here, we introduce a modified donor blood flow-preserved cross-leg anterolateral thigh flap procedure and evaluate its clinical efficacy.MethodsBetween January 2013 and December 2019, 22 patients (range 10 to 64 years old) with unilateral lower limb injury underwent modified donor blood flow-preserved cross-leg anterolateral thigh flap procedures. Among them, 16 cases were traffic accidents, 5 cases were persistent ulcers, and 1 case was a degloving injury. The arterial pedicle of the flap was prepared in a Y-shaped fashion and microanastomosed to the posterior tibial artery of intact leg in a flow-through style. A split-thickness skin graft was applied to wrap the vascular pedicle after anastomosis. The flap was designed in a single or bilobed fashion according to the shape of the tissue defect. The operation time, the intraoperative blood loss and the length of hospital stays were recorded. The vascular pedicle was divided 4 weeks after anastomosis. Doppler ultrasound was performed to evaluate the blood flow of the donor posterior tibial artery during postoperative follow-up.ResultsAll 22 flaps survived. The tissue defects ranged from 12 × 6 to 21 × 18 cm2. The flap sizes ranged from 14 × 7.5 to 24 × 21 cm2. The average operation time, intraoperative blood loss and length of hospital stays were 6.73 ± 1.49 h, 280.95 ± 59.25 ml and 30.55 ± 2.52 days, respectively. Eighteen flaps were designed in a single fashion, while four were in bilobed fashion. Twenty patients underwent fasciocutaneous flap transplantations, while two underwent musculocutaneous flap transplantations. Two cases developed local lysis of the flap which healed after further debridement. Direct suture of the incision after flap harvest was performed in 16 cases, while additional full-thickness skin grafting was performed in the remaining 6 cases. Further bone transport procedures were performed in 15 patients who had severe tibia bone defects. The blood flow of donor posterior tibial artery was confirmed in all patients during follow-ups. All patients recovered flap sensation at the final follow-up. The postoperative follow-ups ranged from 18 to 84 months, and no long-term complications were observed.ConclusionsThe modified donor blood flow-preserved cross-leg anterolateral thigh flap procedure is an ideal method to repair severe lower limb trauma with tibial artery occlusion which avoids sacrificing the major artery of the uninjured lower limb.

Biomimetic design strategy of complex porous structure based on 3D printing Ti-6Al-4V scaffolds for enhanced osseointegration

Ti6Al4V is extensively utilized as orthopedic implants owing to its outstanding biocompatibility and mechanical qualities. However, because Ti6Al4V has a high strength, it is substantially stiffer than natural bone, resulting in stress shielding. To resolve this issue, an effective way is to construct porous titanium alloy scaffolds with adjustable pore size and porosity, and 3D printing technology may be utilized to build complex bespoke forms that fit our specifications. In this work, 3D-printed porous Ti6Al4V scaffolds with imitation of trabecular structure (ITS) and the corresponding regular structure scaffolds (RS), which have three different average pore size (300/400/500 μm), were prepared by selective laser melting technology. A series of in vitro and in vivo experiments were used to assess the scaffolds' physiochemical characteristics, as well as their osseointegration capabilities. The findings revealed that the ITS scaffolds were conducive to cell proliferation and osteogenic differentiation. And the in vivo performance was examined through rabbit tibia bone defect model, the results demonstrated that the ITS scaffolds with average pore size of 400 μm showed the ideal osseointegration potential. Therefore 3D-printed titanium scaffolds with imitation of trabecular structure provides a viable bio-inspired structural and functional design method of titanium alloy orthopedic implants.