Objective: This study aimed to compare retrograde intramedullary nailing (RIMN) and femoral locked plating (FLP) in the management of periprosthetic supracondylar femur fractures (PSFF) following total knee arthroplasty (TKA), focusing on fracture healing, blood loss, functional outcomes, and complication rates. Methods: Thirty-one patients surgically treated for PSFF between 2015 and 2021 were retrospectively analyzed. According to the fixation method, patients were divided into two groups: FLP (n=19) and RIMN (n=12). Group allocation was based on fracture pattern, distal fragment length, and prosthesis compatibility. Fractures were classified according to the Su system. Operative parameters, intraoperative blood loss, transfusion requirement, union time, complications, and functional outcomes (Knee Society Score, KSS) were evaluated. Statistical analysis was performed using SPSS 23.0, with a significance level of p<0.05. Results: No significant difference was found between groups in terms of demographics, fracture type, or complication rate (p>0.05). The RIMN group showed significantly lower intraoperative blood loss and transfusion requirements (p<0.001 and p=0.016, respectively). KSS and KSS-functional scores were significantly higher in the RIMN group (p=0.022 and p=0.028). There was no significant difference in union time between the two fixation methods. Conclusion: Both fixation methods are effective for PSFF treatment; however, RIMN provides advantages in terms of reduced blood loss, lower transfusion needs, and superior postoperative functional outcomes. Surgical method selection should be individualized according to bone quality, fracture morphology, and prosthesis compatibility.

Nonlinear continuous gradient-regulated porous architectures fabricated by selective laser melting for enhanced biomechanical compatibility

Background:Minimal resection total ankle arthroplasty (TAA) has been linked to an increased incidence of tibial component lucency in large preoperative coronal plane deformity. Lucency has been linked to implant loosening. Because radiographic lucency may reflect implant micromotion, lack of bony ingrowth and/or early component loosening, we analyzed a series of TAA cases with varying degrees of preoperative coronal deformity. Our primary aim was to determine if larger preoperative tibiotalar angles were associated with increased postoperative tibial component lucency in the Cadence TAA system.Methods:A retrospective review of a single surgeon’s TAA procedures using the Cadence prosthesis was conducted. Patients aged ≥18 years who underwent Cadence TAA from January 1, 2018, to December 31, 2023, were included; those with <12 months’ follow-up or poor-quality radiographs were excluded. Lucency was defined as a radiolucent line at the interface between the tibia and the tibial component that was greater than 0.5 mm at any point. The patient’s final follow-up radiograph was used for this analysis. Pre- and postoperative tibiotalar alignment was recorded.Results:Fifty-five ankles were examined. The average follow-up duration was 29.8 months. Sixteen patients (29%) had no deformity. Twenty-seven patients (49%) had less than 15 degrees of angulation and 12 patients (22%) had more than 15 degrees of angulation. Postoperatively, all ankles were corrected to within 3.7 degrees of a coronal tibiotalar angle of 90 degrees. Comparisons among the 3 groups with χ2 tests and analyses of variance revealed no significant differences in tibial interface lucency across any zone (P > .05).Conclusion:Aseptic loosening in TAAs, indicated by peri-implant lucency, is a recognized mode of failure. Recent studies suggest that preoperative coronal tibiotalar angles greater than 15 degrees increase the risk of failure when using minimal resection TAA. In this short-term, single-surgeon cohort, there were no differences in peri-implant lucency between groups. Findings should be interpreted cautiously, given the limited follow-up and statistical power.Level of Evidence:Level IV, retrospective analysis.

IntroductionEwing′s sarcoma of the ulna is rare, and its wide resection poses challenges for preserving upper limb function. Elbow reconstruction must ensure joint stability and forearm mobility. Conventional alternatives, such as bone grafts and prostheses, have limitations, including a high risk of complications.ObjectiveThis study was aimed at reporting a case of elbow reconstruction using radial neck transposition to the humeral trochlea after ulnar resection for Ewing′s sarcoma, evaluating the functional outcomes of this technique.MethodsA 17‐year‐old male patient with Ewing′s sarcoma in the ulnar diaphysis underwent complete ulnar resection. Radial neck transposition to the humeral trochlea was performed. Follow‐up included functional assessment using the Musculoskeletal Tumor Society (MSTS) scale and postoperative imaging.ResultsAfter 2 years, the patient had an MSTS score of 28/30, with preserved wrist and hand mobility, full pronation, and supination reduced to half. Radiographic follow‐up demonstrated proper alignment of the reconstruction, with no instability or bone resorption.ConclusionRadial neck transposition proved to be a viable alternative for elbow reconstruction after ulnar resection, providing stability and functional preservation. Further studies are needed to validate its application on a larger scale.

Objective: To evaluate the feasibility of intraoperative hearing monitoring using Auditory Steady-State Responses (ASSR) during one-stage tympanoplasty in patients with chronic otitis media.Materials and Methods: 5 patients with chronic otitis media underwent ossiculoplasty with autologous bone prostheses. Intraoperative hearing monitoring was performed using ASSR. Results were compared with pure-tone audiometry obtained before surgery and 6 and 12 weeks postoperatively.Results: In all cases, improvement in hearing function was confirmed by postoperative audiometry and intraoperative ASSR recordings. A reduction in the air–bone gap and a positive trend in auditory thresholds were observed.Conclusions: Intraoperative hearing monitoring with ASSR during one-stage tympanoplasty is a promising method for improving surgical outcomes in chronic otitis media. Further studies are needed to standardize the methodology and validate its clinical significance.

Background The concept of overdentures developed as a simple, time saving and cost-effective alternative to prolong the retention, stability and function of the last few remaining teeth in a compromised dentition. Tooth supported overdentures are more stable, retentive and patients can chew greater than conventional complete dentures.CaseA 70-year-old female patient reported to the Department of Prosthodontics and Crown-Bridge, BPKIHS, Dharan for prosthetic rehabilitation of maxillary and mandibular edentulous ridges. Intra oral examination revealed, completely edentulous lower arch and 11, 21 and 22 teeth were present in upper arch. Treatment plan was made to rehabilitate tooth supported maxillary overdenture prosthesis and conventional mandibular denture. ConclusionTooth supported overdenture has many advantages over implant supported prosthesis such as, simple, economical, time saving, preserve tooth structure and alveolar bone, provide retentive and stable prosthesis, preserve proprioception, patient psychological benefits. So, now a day this treatment modality overshadowed but still not omitted.

Selective laser melting is one of the most common additive manufacturing technologies, appreciated for its precision and accuracy in the fabrication of complex tridimensional parts from metallic powders, by tridimensional computer-assisted design (CAD-3D). The parts fabricated by this method have a remarkable wear and corrosion resistance, high hardness and good fiability. This manufacturing technology has been applied in various fields, such as automotive industry, aerospace sector and medical field (for bone prostheses and dental applications). The process involves the total melting of the metallic powder by means of a laser beam, the energy and power of which can be controlled. Subsequently, the material solidifies from the liquid phase and the physical-chemical and mechanical characteristics of the finished products are influenced by the technological parameters used in the process. The heat treatments applied to the processed parts, especially those for medical applications, are meant to reduce internal stresses, to improve the microstructure with favorable effects on the material’s corrosion resistance and biocompatibility. In this way, the exploitation sustainability of the implants and medical devices, processed through selective laser melting, from Co-Cr-W alloy powders, can be improved

Zygomatic implants provide a viable solution for the rehabilitation of patients with severe maxillary atrophy, offering improved function and aesthetics in cases where conventional implant placement is not feasible due to insufficient bone quantity and quality. Severe maxillary atrophy, often resulting from tooth loss and sinus expansion, presents significant challenges for implant supported prostheses. Zygomatic implants eliminate the need for extensive bone grafting by anchoring into the zygomatic bone, enabling fixed or removable prostheses. This case report presents two patients with atrophic maxilla rehabilitated using zygomatic implants: one with a history of failed implants and grafts and another with cleft lip and palate. Both patients achieved satisfactory outcomes with minimal complications. Zygomatic implants offer a reliable, long-term solution for severe maxillary atrophy, provided that detailed pre-surgical planning and experienced surgical teams are involved to minimize risks and optimize outcomes.

ABSTRACTImplant‐supported overdenture is a lifesaver treatment plan for edentulous patients. Implant numbers and positions in the maxilla and mandible are controversial, but in more studies on a minimum number of implants, which is at least four implants in the maxilla and two implants in the mandible, there is a consensus. Also, the attachment system (splinted vs. unsplinted) does not have a significant effect on bone loss, implant and prosthesis survival rate, and clinical complications. Palateless maxillary overdentures supported on four implants may improve taste sensation and reduce gag reflex without negatively affecting retention, resistance, and chewing ability. The aim of this study was to present three maxillary implant‐supported overdenture cases with four implants without palatal coverage.

The article is devoted to topical issues of improving the durability and functional reliability of orthopaedic structures based on dental implants. The authors justify the significance of the research topic, which is determined by the need for accurate prediction of the biomechanical behaviour of implant systems, including the influence of the type of implant and abutment connection, the fixation method, and the angle of the implant. The relevance of this research is confirmed by the active introduction of mathematical modelling methods, in particular the finite element method (FEM), which allows analysing the distribution of loads and stresses in bone tissue and prosthesis components. However, the aspects of the influence of various connection configurations (external, internal, conical) and fixation methods (cemented, screw) on the long-term stability of orthopaedic structures remain insufficiently studied. The study conducted a systematic analysis of domestic and foreign scientific publications from the PubMed, Medline, Cochrane, eLIBRARY, and CyberLeninka databases devoted to mathematical modelling in orthopaedic dentistry. A set of methods was used, including comparative analysis, data summarisation, assessment of result reliability, and critical analysis of clinical studies. The results of the study showed that internal and conical connections are more resistant to micromobility and stress concentration than external ones; screw fixation provides better stability under high loads, while cemented fixation requires further study in the long-term; the angle of the implant significantly affects the distribution of stresses in bone tissue. Conclusion. Despite advances in mathematical modelling, there is still a need to standardise analysis methods and conduct additional studies to optimise the parameters of implant systems. The data obtained can be used to improve the accuracy of orthopaedic treatment planning and reduce the risk of complications.

The clinical presentation of infection complicating fracture fixation is extremely varied, ranging from obvious purulence and exposed implants to subclinical infection with subtle signs and symptoms. Diagnosis of these silent subtle infections is difficult, and a combination of clinical features, radiology, biomarkers and histology is used for making an accurate diagnosis. We looked at the diagnostic utility of F-18 FDG PET CT scans in the diagnosis of late fracture related infection (12 weeks after the index surgery).Patients with metallic trauma implant in situ and ‘suspected’ fracture related infection (AO/ EBJIS criteria) were included in the study. All patients underwent F-18 FDG PET scans prior to surgery necessitated by the suspected infection. PET CT scans were considered positive if increased diffuse 18F-FDG uptake was detected around the implant (especially at the bone–prosthesis interface), or in the surrounding tissue and negative if there was no uptake in the region. Post surgery patients were diagnosed positive for fracture related infection if at least two deep cultures grew the same organism or histopathological analysis showed more than 5 PMN/high power field. The diagnostic utility of the 18F-FDG PET/CT scan in diagnosing FRI was assessed using culture and histopathology as a reference.17 patients, inclusive of 4 diabetics with metallic trauma implants suspected of fracture related infection underwent a F-18 FDG PET CT scan prior to surgery. 9 patients presented more than a year after the index surgery and 8 patients had an associated fracture non-union along with the suspected infection. 14 patients had FDG tracer uptake suggestive of infection (PET positive), while the remaining 3 patients were PET negative. All 14 PET positive patients were also diagnosed as fracture related infection positive by histopathological criteria. However, only 11 PET positive patients were culture positive with Staph aureus being the most commonly isolated microorganism (n=5). 18 FDG PET CT demonstrated 100 % sensitivity (95% CI : 26.24 −100 %) and 100 % specificity (95 % CI :76.84 −100 %), negative predictive value and positive predictive value of 100 % in detecting fracture related infection in this study18F-FDG PET/CT scan is useful tool for the diagnosis of fracture related infection associated with a trauma implant especially when clinical presentation is not obvious.

Purpose This study aims to propose and validate a pixel-based method for direct printing of customized bone implants and prostheses from two-dimensional medical imaging data, eliminating the need for intermediate standard tessellation language (STL) files. The method reduces processing time and human intervention while preserving natural bone structures. Design/methodology/approach The proposed method uses pixel-based additive manufacturing (AM) technologies, such as digital light processing and binder jetting technology to print the 3D part directly from bitmap data. The process is validated by comparing its accuracy and efficiency with conventional STL-based workflows in replicating the trabecular structure of bone tissues. Findings A pixel-based direct printing approach successfully preserves the intricate trabecular structure of bones while significantly reducing processing time and eliminating the requirement of intermediate 3D reconstruction of bones. The results demonstrate comparable accuracy and efficiency to conventional STL-based workflows, highlighting its potential for patient-specific medical applications and surgical planning. Social implications The proposed direct bitmap-to-print approach can potentially improve accessibility to patient-specific implants and prostheses, particularly in resource-constrained societies, by simplifying the workflow and reducing costs. Originality/value This study introduces a novel direct bitmap-to-print method for medical AM, bypassing the traditional STL-based workflow. By using pixel-based AM technologies, the proposed method provides a faster and more efficient solution for producing patient-specific bone models, addressing key challenges in traditional workflows.

Novel bispherical augments developed for acetabular defect reconstruction, which combined with acetabular components, have shown excellent results in clinical follow-up. This study aims to evaluate the primary stability of them in severe acetabular defect reconstruction and biomechanical effect using different combine methods in the component-augment interface, and to further explain their value in clinical applications. Nine composite hemipelvis specimens were prepared with a Paprosky II defect. A porous titanium acetabular shell and bispherical augment were combined and implanted for acetabular defect reconstruction. The augment was fixed to the hemipelvis using screws, while three specimens per groups of three groups were varied by different fixation techniques between the augments and acetabular components: (1) screw fixation only, (2) cement fixation only, and (3) screw and cement fixation. The combined components and hemi pelvic specimens were cyclically loaded (500 cycles) with three different levels of loads (maximum 0.5 kN, 0.9 kN, and 1.8 kN). All constructs had micromotions of less than 99μm, and bony ingrowth could be achieved between the prostheses and the bone in 3-30% and 5-50% loads. The cement groups showed the maximum relative movement in the interface between the bone and combined prosthesis, especially when the load was increased to 1.8 kN (100%), while in which the hybrid groups had the minimum value. The study indicates that acetabular defect reconstruction utilizing the bispherical augments can achieve excellent primary stability, which provides the mechanical condition of bone ingrowth for prostheses and augments. The hybrid fixation is the most reliable of them, even under full loads.

Photo-curable layered double hydroxide-hyaluronic acid-composite hydrogels with multifunctional properties for growth factor-free bone regeneration.

The reconstruction of large osteoarticular defects caused by tumor resection or severe trauma remains a clinical challenge. Current metal prostheses exhibit a lack of osteo-chondrogenic functionality and demonstrate poor integration with host tissues. This often results in complications such as abnormal bone absorption and prosthetic loosening, which may necessitate secondary revisions. Here, we propose a paradigm-shifting "living prosthesis" strategy that combines a customized 3D-printed hollow titanium humeral prosthesis with engineered bone marrow condensations presenting bone morphogenetic protein-2 (BMP-2) and transforming growth factor-β3 (TGF-β3) from encapsulated silk fibroin hydrogels. This innovative approach promotes in situ endochondral defect regeneration of the entire humeral head while simultaneously providing immediate mechanical support. In a rabbit model of total humerus resection, the designed "living prosthesis" achieved weight, macroscopic and microscopic morphologies that were comparable to those of undamaged native joints at 2 months post-implantation, with organized osteochondral tissues were regenerated both around and within the prosthesis. Notably, the "living prosthesis" displayed significantly higher osteo-integration than the blank metal prosthesis did, as evidenced by a 3-fold increase in bone ingrowth and a 2-fold increase in mechanical pull-out strength. Furthermore, the "living prosthesis" restored joint cartilage function, with rabbits exhibiting normal gait and weight-bearing capacity. The successful regeneration of fully functional humeral head tissue from a single implanted prosthesis represents technical advance in designing bioactive bone prosthesis, with promising implications for treating extreme-large osteochondral defects.

IntroductionCranioplasty involves repairing the skull defect using an autologous bone flap or synthetic molds. The temporalis muscle, detached during decompressive craniectomy (DC), may be reattached to the bone flap for better cosmetic reconstruction. Along with the masseter and pterygoid muscles, the temporalis muscle significantly contributes to the human bite force. In this study, we analyze patients' bite force in which the temporalis muscle was either dissected and reattached or left undisturbed during cranioplasty.Materials and MethodsAll patients who previously underwent DC for traumatic brain injury or stroke were grouped into two, depending on the method of cranioplasty. In group 1, patients underwent temporalis muscle dissection and reattachment to the bone flap or prosthesis. In group 2, the temporalis muscle was left undisturbed. The bite force of the subjects was measured bilaterally in both groups by a gnathodynamometer before cranioplasty and 3 months after the surgery. We compared the difference in bite force of the subjects individually on both sides, preoperatively and postoperatively, as well as between the groups.ResultsThis study included 36 patients over 18 years of age, with 18 patients in each group. Preoperatively, the bite force of all the subjects was decreased on the side of the DC compared with the normal side. After cranioplasty, the bite force significantly improved compared with preoperative values in both groups.ConclusionTemporalis dissection can be safely done during cranioplasty. There is improvement in bite force after cranioplasty with or without temporalis dissection.

Aseptic loosening is the primary cause of bone prosthesis failure, commonly attributed to inadequate osseointegration due to coatings misaligned with bone regeneration. Here, we modify the titanium surface with a mussel-inspired peptide to form a 3,4-dihydroxyphenylalanine (DOPA)-rich coating, then graft N3-K15-PVGLIG-K23 (P1) and N3-Y5-PVGLIG-K23 (P2), which are composed of anti-inflammatory (K23), angiogenic (K15), osteogenic (Y5), and inflammation-responsive (PVGLIG) sequences, onto the surface via click chemistry, forming the DOPA-P1@P2 coating. DOPA-P1@P2 promotes bone regeneration through sequential regulation. In the initial stage, the outermost K23 induces M2 macrophage polarization, establishing a pro-regenerative immune microenvironment. Subsequently, K15 and Y5, exposed by the release of K23, enhance angiogenesis and osteogenesis. In the final stage, DOPA-P1@P2 outperforms the TiO₂ control, showing a 161% increase in maximal push-out force, a 207% increase in bone volume fraction, and a 1409% increase in bone-to-implant contact. These findings show that DOPA-P1@P2 efficiently enhances interfacial osseointegration by sequentially regulating bone regeneration, providing viable insights into coating design.

Prosthesis loosening is the leading cause of postoperative revision in unicompartmental knee arthroplasty (UKA). The deviation of medial and lateral translational installation of the prosthesis during surgery is a common clinical phenomenon and an important factor in increasing the risk of prosthesis loosening. This study established a UKA finite element model and a bone-prosthesis fixation interface micromotion prediction model. The predicted medial contact force and joint motion of the knee joint from a patient-specific lower extremity musculoskeletal multibody dynamics model of UKA were used as boundary conditions. The effects of 9 femoral component medial and lateral translational installation deviations on the Von Mises stress of the proximal tibia, the contact stress, and the micro-motion of the bone prosthesis fixation interface were quantitatively studied. It was found that compared with the neutral position (a/A of 0.492), the lateral translational deviation of the femoral component significantly increased the tibial Von Mises stress and the bone-prosthesis fixation interface contact stress. The maximum Von Mises stress and the maximum contact stress of the fixation interface increased by 14.08% and 143.15%, respectively, when a/A was 0.361. The medial translational deviation of the femoral component significantly increased the bone-prosthesis fixation interface micro-motion. The maximum value of micromotion under the conditions of femoral neutral and medial translation deviation was in the range of 20-50 μm, which is suitable for osseointegration. Therefore, based on considerations such as the micromotion range suitable for osseointegration reported in the literature, the risk of reducing prosthesis loosening, and factors that may induce pain, it is recommended that clinicians control the mounting position of the femoral component during surgery within the safe range of 0-4 mm medial translation deviation.

Up to now, how to implement the optimal regenerative repair of large load-bearing bone defects using artificial bone prosthesis remains to be an enormous challenge in clinical practice. Titanium-based alloys, especially Ti6Al4V, are applied as artificial bone grafts due to their favorable mechanical property and biocompatibility, assisted by personalized customization of 3D-printing to completely match with the bone defect. However, their bioinert peculiarity restricts osteointegration at the interface between bone and titanium-based implants and bone growth into porous titanium-based scaffolds, for lack of bone regeneration with the aid of blood vessels and neural networks. Of note, ample blood delivery and integral innervation are pivotal to the survival of artificially tissue-engineered bones. Herein, the functionalized surface of 3D printed titanium alloy scaffolds driven immunoregulatory neuro-vascularized osseointegration is delved. Bone-like micro/nano morphology and chemical composition of calcium-rich formula are scrutinized to accelerate the process of bone defect repair, including inflammatory response, angiogenesis, neurogenesis, and osseointegration. Micro/nano-topographic calcium titanate (CaTiO3) coating, especially 10%H2O2-Ca, driven immunoregulatory neuro-vascularized osseointegration is validated and its underlying mechanism is attributed to the signaling pathway of TNF-α /oxidative phosphorylation, providing an effective tactic of the bone tissue-engineered scaffold with surface functionalization-driven immunoregulatory neuro-vascularized osseointegration for clinical large segmental bone defects.

Periprosthetic distal femoral fractures present significant challenges in management due to high morbidity and mortality rates. We discuss the treatment options based on fracture pattern, location and status of the prosthesis. Surgical treatment is favored over nonoperative management to enable early mobilization and prevent complications. The Rorabeck and Taylor classification system for periprosthetic fractures was used to identify the prosthesis status. For stable prosthesis, fixation method was decided based on the location of the fracture from the flange, level of comminution and bone quality. Well-fixed prosthetic components require internal fixation with locking plates either single or double or retrograde intramedullary interlocking nail. A revision knee replacement could be done in patients with loose prosthesis and good bone stock. Distal femoral replacement was required in patients with loose components and poor bone stock along with fracture. Treatment of osteoporosis is an integral part of the management. We have described a surgical algorithm to be followed based on the above protocol. Treatment of periprosthetic fractures after TKA needs a tailored treatment approach based on factors such as bone quality, prosthesis stability, fracture location, and patient-specific considerations. A personalized strategy ensures optimal outcomes by addressing the unique challenges of each case and balancing the need for stability, mobility, and long-term implant survival.The surgical algorithm we have described helps in managing periprosthetic fractures effectively.