Augmented versus non-augmented Trochanteric Fixation Nail-Advanced (TFNA) nails for treating trochanteric fractures in patients over sixty-five years of age.

PURPOSE: Intramedullary nailing is a common treatment for pertrochanteric fractures. However, implant-related mechanical failures, such as cut-out and cut-through, lead to higher rates of revision surgery, loss of autonomy, and mortality. Cemented augmentation enhances the bone-implant interface. This study compared the frequency of mechanical failures between augmented and non-augmented Trochanteric Fixation Nail-Advanced (TFNA) nails. METHODS: This descriptive, retrospective study at a level 1 trauma centre included patients aged > 65 years with pertrochanteric fractures treated by a short augmented or non-augmented TFNA nail. The primary outcome was the comparison of cut-out or cut-through rates between groups at three and six months postoperatively. RESULTS: Of the 181 patients analysed, 103 had augmented TFNA nails and 78 had non-augmented TFNA nails. There were no statistically significant differences between groups in terms of demographic characteristics, AO/OTA classification, or quality of reduction. The failure rate was significantly lower in the augmented group than in the non-augmented group: 1 (0.97%) versus 9 (11.54%) (p = 0.005). At six months postoperatively, there was no significant difference between the two groups concerning functional recovery, as measured by the Parker and EuroQoL 5-Dimensions scores. CONCLUSIONS: For patients aged over 65 years, the use of the augmented TFNA nail may reduce the risk of fixation failures such as cut-out.

Mechanical Complications of Proximal Femur Fractures Treated with Intramedullary Nailing: A Retrospective Study.

Background and Objectives: This retrospective cohort study analyzes mechanical complications in hip fracture surgery using the Trochanteric Fixation Nail-Advanced (TFNA) implant. It investigates the correlation of these complications with demographic, intraoperative, and radiological factors, aiming to identify associated risk factors and suggest improvements in clinical surveillance and treatment strategies. Materials and Methods: We enrolled 253 patients diagnosed with pertrochanteric hip fractures treated between 2017 and 2021, with 126 meeting the criteria for a minimum 6-month follow-up. Data on demographics, American Anesthesia Association Classification (ASA), comorbidities, AO/OTA [AO (Arbeitsgemeinschaft für Osteosynthesefragen)/OTA (Orthopedic Trauma Association)] fracture classification, procedural details, and time to failure were collected. Radiographs were evaluated for reduction quality, the tip-apex distance (TAD), progressive varus deviation, and identification of mechanical complications. Statistical analysis was performed using SPSS software. Results: The predominant AO/OTA fracture classification was 31A2 in 67 cases (52.7%). Reduction quality was deemed good or acceptable in 123 cases (97.6%). The mean time to failure was 4.5 months (range: 2.2-6). The average TAD was 18 mm (range: 1.2-36), with a mean progressive varus deviation of 2.44° (range: 1.30-4.14). A good or acceptable reduction quality was observed in 97.6% of cases. Mechanical complications occurred in 21.4% of patients, with significant associations found with the lateral cortex fracture, use of a TFNA implant with a 130° angle, open reduction, and absence of prior osteoporosis treatment. Conclusions: The study provides insights into mechanical complications in proximal femur fractures treated with the TFNA nail, emphasizing the need for enhanced clinical and radiographic surveillance, especially in patients without osteoporosis treatment. Our findings support the necessity for further clinical studies comparing these outcomes with other implant designs and underscore the importance of personalized treatment strategies to reduce complication rates.

Medial migration of the helical blade with penetration into the acetabulum: a rare complication using the TFNA nail.

PURPOSE: To determine the frequency and possible reasons of medial migration with penetration into the acetabulum (MMPA) of the helical blade when using the Trochanteric Fixation Nail Advanced (TFNA) is used for treatment of pertrochanteric fractures. METHODS: All patients with pertrochanteric femoral fracture, treated by intramedullary femoral nailing with the TFNA, were retrospectively reviewed for MMPA of the helical blade. Epidemiological parameters, additional procedures, distance of medial migration, time from primary operation to revision as well as type of revision were assessed. RESULTS: 4 of 153 patients treated with the TFNA developed an MMPA of the helical blade (risk = 2.6%), with a mean medial migration of the blade of 11.6 mm (SD 8.8). The mean time from initial operation to revision surgery was 70 days (SD 30). All patients were revised by conversion to cemented total hip arthroplasty. CONCLUSION: MMPA of the helical blade is a rare but potentially hazardous complication of femoral nailing with the TFNA femoral nail, resulting in the necessity for revision surgery and total hip arthroplasty.

Which head element is more effective for cement augmentation of TFNA? Helical blade versus lag screw.

BACKGROUND: Early fixation and rehabilitation is the gold standard treatment for intertrochanteric femur fractures. Cement augmentation through perforated head elements has been developed to avoid postoperative complications such as cut-out or cut-through. The purpose of this study was to compare two head elements in terms of cement distribution using computed tomography (CT) and to examine their initial fixation and clinical outcomes. METHODS: Elderly patients who had intertrochanteric fractures were treated with a trochanteric fixation nail advanced (TFNA) helical blade (Blade group) or a TFNA lag screw (Screw group). In both groups, 4.2 mL of cement was injected under an image intensifier (1.8 mL of cement was directed cranially and 0.8 mL each caudally, anteriorly, and posteriorly). Patient demographics and clinical outcome were investigated post-operatively. Cement distribution from the center of the head element was evaluated with CT. Maximum penetration depth (MPD) were measured in the coronal and sagittal planes. On each axial plane, the cross-sectional areas in the cranial, caudal, anterior and posterior directions were calculated. The sum of cross-sectional areas (successive 36 slices) was defined as the volume of the head element. RESULTS: The Blade group included 14 patients, and the Screw group included 15 patients. In the Blade group, MPD in the anterior and caudal direction was significantly greater than that in the posterior direction (p < 0.01). In the Screw group, volume in the cranial and posterior direction was significantly greater than that in the Blade group (p = 0.03). Subsequently, the total volume in the Screw group was significantly larger than that in the Blade group (p < 0.01). No significant correlation was detected between bone mineral density, T score, young adult mean, and total cement volume. Change in radiographic parameters and clinical outcome such as Parker score and visual analog scale were similar in both groups. No patients suffered from cut-out / cut through or non-union. CONCLUSIONS: The position of cement distribution through the lag screw is different from that through the helical blade, and the total volume of the head element is significantly larger in the lag screw. Both groups had similarly effective results in terms of mechanical stability after surgery, postoperative pain and early phase of rehabilitation. TRIAL REGISTRATION: Current Controlled Trials ISRCTN45341843, 24/12/2022, Retrospectively registered.

Retrospective evaluation of radiological and clinical outcomes after surgical treatment of proximal femur fractures utilizing TFNA.

INTRODUCTION: The aim of this study was to evaluate the clinical and radiological outcomes of patients treated with the TFN-Advanced™ Proximal Femoral Nailing system (TFNA¸ DePuy Synthes, West Chester, PA) including intra- and postoperative complications. MATERIALS AND METHODS: All patients with an acute proximal femur fracture consequently treated with a TFNA between September 2014 and December 2018 were evaluated. Clinical and radiological data were assessed for intra- and postoperative complications, including treatment failure. In addition, intra- and postoperative X-rays were used to determine the position of the implant, and any migration, via tip-apex-distance (TAD) and the caput-collum-diaphyseal angle (CCD). The accuracy of the fracture reduction was rated by both observers according to Baumgartners criteria. RESULTS: 275 consecutive patients (mean age 77.5 ± 14.1; 70.2% female) were included. The predominant OTA/AO fracture classification was 31A2 (140 cases, 50.7%). The average surgical time was 69 min (± 39.8). The reduction quality was good in 253 cases (92.0%) and acceptable in 22 cases (8.0%). In 18 cases, a pre-defined primary outcome parameter (6.5%) was recorded after a mean of 8.2 ± 8.0 months. During the observational period, 19 patients (6.9%) required a total of 23 additional surgeries. Implant removal was not considered a failure in the absence of pain. Significant group differences were observed with younger age (p = 0.001), lower Charlson Comorbidity Index (CCI)-score (p = 0.041) and lower rate of osteoporosis (p = 0.015) in the failure group. There were no cases of cut-out or cut-through among the patients who underwent augmentation as part of osteosynthesis. CONCLUSIONS: Proximal femur fractures treated with the TFNA show low complication rates and high levels of radiological healing. Implant-related complications might be more common in patients with younger age, a lower CCI-score and lower frequency of osteoporosis. Usage of cement augmentation could potentially be beneficial to reduce postoperative cut-through and cut-out.

Use of a Trochanteric Fixation Nail-Advanced (TFNA) with cement augmentation for treatment of trochanteric fractures in patients greater than sixty five years of age.

PURPOSE: Intramedullary nailing is the standard treatment of trochanteric fractures. Mechanical failure such as cut-out and cut-through are associated with high rates of revision surgery, functional impairment, and mortality. The aim of the study was to evaluate the rate of mechanical failure of the cement augmented screws of Trochanteric Fixation Nail-Advanced (TFNA) nails. PATIENTS AND METHODS: A descriptive, retrospective, multi-operator, single-centre study was performed at our level 1 trauma centre between June 2019 and June 2020. Patients were included if they were > 65 years of age, presented with a trochanteric fracture treated with an augmented TFNA nail with 6 months of follow-up. The primary outcome was fixation failure rate (cut-out or cut-through) at three and six post-operative months. Secondary endpoints were intra-operative data, clinical scores, and radiographic analysis. RESULTS: Forty-five patients (38 women and 7 men) were analysed. The mean age was 82.84 years (65-102, 9.50). There were no instances of mechanical failure in our series, after either three or six months of follow-up. No patient exhibited cut-out or cut-through. The mean amount of cement injected was 4.72 mL (3-6; 1.05). The mean length of surgery was 37.59 min (25-55; 6.48), and the mean intra-operative radiation exposure was 91.47 cGycm2 (25.04-201.81; 51.40) for a mean duration of 43.11 s (17-86; 16.81). The mean duration of hospitalisation was 6.38 days (2-11; 2.27). CONCLUSIONS: Our clinical results suggest that cement-augmented TFNA screws can be successfully used in the management of trochanteric fractures in patients > 65 years of age.

Impact of Anterior Malposition and Bone Cement Augmentation on the Fixation Strength of Cephalic Intramedullary Nail Head Elements.

Background and Objectives: Intramedullary nailing of trochanteric fractures can be challenging and sometimes the clinical situation does not allow perfect implant positioning. The aim of this study was (1) to compare in human cadaveric femoral heads the biomechanical competence of two recently launched cephalic implants inserted in either an ideal (centre-centre) or less-ideal anterior off-centre position, and (2) to investigate the effect of bone cement augmentation on their fixation strength in the less-ideal position. Materials and Methods: Fourty-two paired human cadaveric femoral heads were assigned for pairwise implantation using either a TFNA helical blade or a TFNA screw as head element, implanted in either centre-centre or 7 mm anterior off-centre position. Next, seven paired specimens implanted in the off-centre position were augmented with bone cement. As a result, six study groups were created as follows: group 1 with a centre-centre positioned helical blade, paired with group 2 featuring a centre-centre screw, group 3 with an off-centre positioned helical blade, paired with group 4 featuring an off-centre screw, and group 5 with an off-centre positioned augmented helical blade, paired with group 6 featuring an off-centre augmented screw. All specimens were tested until failure under progressively increasing cyclic loading. Results: Stiffness was not significantly different among the study groups (p = 0.388). Varus deformation was significantly higher in group 4 versus group 6 (p = 0.026). Femoral head rotation was significantly higher in group 4 versus group 3 (p = 0.034), significantly lower in group 2 versus group 4 (p = 0.005), and significantly higher in group 4 versus group 6 (p = 0.007). Cycles to clinically relevant failure were 14,919 ± 4763 in group 1, 10,824 ± 5396 in group 2, 10,900 ± 3285 in group 3, 1382 ± 2701 in group 4, 25,811 ± 19,107 in group 5 and 17,817 ± 11,924 in group 6. Significantly higher number of cycles to failure were indicated for group 1 versus group 2 (p = 0.021), group 3 versus group 4 (p = 0.007), and in group 6 versus group 4 (p = 0.010). Conclusions: From a biomechanical perspective, proper centre-centre implant positioning in the femoral head is of utmost importance. In cases when this is not achievable in a clinical setting, a helical blade is more forgiving in the less ideal (anterior) malposition when compared to a screw, the latter revealing unacceptable low resistance to femoral head rotation and early failure. Cement augmentation of both off-centre implanted helical blade and screw head elements increases their resistance against failure; however, this effect might be redundant for helical blades and is highly unpredictable for screws.

Bent or broken: analysis of set screw fracture in the TFNa implant.

OBJECTIVES: To evaluate set screw fracture in the Trochanteric Femoral Nail Advanced implant (TFNa, Synthes, West Chester, PA) and to identify additional mechanisms of set screw failure in the TFNa. MATERIALS AND METHODS: Patients who had experienced failure after open reduction and internal fixation (ORIF) with the TFNa were identified. TFNa implants were explanted and inspected following revision surgery. Medical device reports (MDRs) and manufacturer's inspection reports describing similar failures for the TFNa in the United States Food and Drug Administration (FDA) Manufacturer and User Facility Device Experience (MAUDE) database were also reviewed. RESULTS: Four set screw fractures that occurred at a level II trauma center were observed. Sixty-seven reported failures were identified in the MAUDE database for review. Twenty-eight failed implants were returned to the manufacturer for inspection with a published inspection report available for analysis. Set screw fractures can occur in the TFNa when the set screw is deployed prematurely into the proximal screw aperture prior to blade/screw insertion. The set screw can also bend and deform if it is advanced against a helical blade/lag screw that is not fully seated into position, thereby potentially compromising its function. CONCLUSION: The TFNa set screw allows for potential fracture during implant insertion leading to uncontrolled collapse, early excessive proximal femoral shortening, and rotational instability of the helical blade/lag screw. Similar failures in the TFNa can be prevented by having the surgeon inspect the proximal screw aperture after attachment of the proximal aiming aim to ensure the set screw has not been deployed prematurely. LEVEL OF EVIDENCE: Therapeutic Level III.

Cementation: for better or worse? Interim results of a multi-centre cohort study using a fenestrated spiral blade cephalomedullary device for pertrochanteric fractures in the elderly.

INTRODUCTION: Cephallomedullary nail fixation is currently the most popular treatment for pertrochanteric fractures. Despite continuous improvement in implant design, fixation failures still occur in a concerning number of cases. This study aims to evaluate the effect of cement augmentation of the new-generation Trochanteric Femoral Nail Advanced (TFNA) perforated spiral blade on complications including fixation failure in the elderly population. MATERIALS AND METHODS: We retrospectively evaluated 107 patients aged 65 + treated for pertrochanteric fractures via TFNA between 2015 and 2019 based on whether cementation was used. Baseline demographics, fracture classifications, and reduction quality were compared. Patients with a follow-up of at least 6 months were analyzed for the primary outcome of fixation failure. All patients, regardless of loss to follow-up within 6 months, were analyzed for other complications including mortality. RESULTS: Seventy-six patients (47 cemented, 29 non-cemented) had a minimum follow-up of 6 months (mean 13 months). There were no statistically significant differences between the two treatment groups in terms of patient demographics, ASA or AO/OTA fracture classification, reduction quality, or length of follow-up. There was a lower rate of fixation failure in the cement-augmented (CA) group versus the non-cement-augmented (NCA) group (2.1% vs 13.8%; p = 0.047). No cut-out or cut-through was observed in the CA group. Seven patients had adverse intraoperative events, with a significantly higher rate of fixation failure in these patients (40% vs 2.8%; p = 0.00). There were no statistically significant differences in 30-day mortality (6.3% CA vs 4.3% NCA; p = 0.632) or 3-month mortality (9.5% CA vs 12.8% NCA; p = 0.589). CONCLUSIONS: Cementation of TFNA blades may decrease risk of fixation failure, however, the surgeon must be aware of potential complications such as cement leakage into the hip joint and be able to manage them as they arise.

Targeted and effective glioblastoma therapy via aptamer-modified tetrahedral framework nucleic acid-paclitaxel nanoconjugates that can pass the blood brain barrier.

Targeted DNA nanoparticles have been identified as one of the most promising nanocarriers in anti-glioma drug delivery. We established a multifunctional nanosystem for targeted glioma therapy. Tetrahedral framework nucleic acid (tFNA), entering U87MG cells and bEnd.3 cells, was chosen to deliver two aptamers, GMT8 and Gint4.T, and paclitaxel. GMT8 and Gint4.T, which specifically bind with U87MG cells and with PDGFRß, were linked with tFNA, to form Gint4.T-tFNA-GMT8 (GTG). GTG was efficiently internalized by U87MG and bEnd.3 cells and penetrated an in-vitro blood-brain-barrier model. GTG loaded with paclitaxel (GPC) had potentiated anti-glioma efficacy. It inhibited the proliferation, migration, and invasion of U87MG cells, and enhanced apoptosis induction in these cells. The expression of apoptosis-related proteins was significantly changed after treatment with GPC, confirming apoptosis induction. Our study demonstrated that the combination of GTG and paclitaxel has great potential for glioma treatment and tFNA shows great promise for use in drug delivery.

Heterogeneous DNA hydrogel loaded with Apt02 modified tetrahedral framework nucleic acid accelerated critical-size bone defect repair.

Segmental bone defects, stemming from trauma, infection, and tumors, pose formidable clinical challenges. Traditional bone repair materials, such as autologous and allogeneic bone grafts, grapple with limitations including source scarcity and immune rejection risks. The advent of nucleic acid nanotechnology, particularly the use of DNA hydrogels in tissue engineering, presents a promising solution, attributed to their biocompatibility, biodegradability, and programmability. However, these hydrogels, typically hindered by high gelation temperatures (∼46 °C) and high construction costs, limit cell encapsulation and broader application. Our research introduces a novel polymer-modified DNA hydrogel, developed using nucleic acid nanotechnology, which gels at a more biocompatible temperature of 37 °C and is cost-effective. This hydrogel then incorporates tetrahedral Framework Nucleic Acid (tFNA) to enhance osteogenic mineralization. Furthermore, considering the modifiability of tFNA, we modified its chains with Aptamer02 (Apt02), an aptamer known to foster angiogenesis. This dual approach significantly accelerates osteogenic differentiation in bone marrow stromal cells (BMSCs) and angiogenesis in human umbilical vein endothelial cells (HUVECs), with cell sequencing confirming their targeting efficacy, respectively. In vivo experiments in rats with critical-size cranial bone defects demonstrate their effectiveness in enhancing new bone formation. This innovation not only offers a viable solution for repairing segmental bone defects but also opens avenues for future advancements in bone organoids construction, marking a significant advancement in tissue engineering and regenerative medicine.

Mechanical outcomes of the TFNA, InterTAN and IMHS intramedullary nailing systems for the fixation of proximal femur fractures.

INTRODUCTION: Hip fractures have become a major public health priority due to their increasing incidence. Intramedullary (IM) nailing has gained popularity as a surgical technique for managing these fractures. However, comparative studies with extramedullary devices indicate potentially increased mechanical complications associated with IM nailing. Specifically, there have been recent reports of early implant fracture associated with the TFNA system. This study compares the rate of mechanical complications between 3 implants. Secondarily, we analysed the factors associated with implant fracture and all other mechanical complications. METHODS: This retrospective study included 803 IM nails performed between 2008-2021 for the fixation of proximal femur fractures at a level 1 trauma centre. We recorded patient demographics, AO fracture classification, implant specification and intra-operative parameters such as tip-apex distance, Cleveland index, reduction quality, presence of medial calcar integrity, neck-shaft angle. The outcomes analysed included implant fracture, lag screw cut-out, >10 mm backing out, autodynamisation, periprosthetic fracture, non-union at 6 months and time to revision surgery. RESULTS: The overall implant fracture rate was 3.1 % (25/803), with no statistically significant difference between the three devices (p = 0.51). The TFNA group included 183 patients with a median follow-up of 1.6 years. The TFNA fracture rate was 2.2 % (4/183) which occurred at 207 +/- 16.66 days post-operatively. The rate of all mechanical complications was 4.9 % in the TFNA group, 12.9 % in the InterTAN group and 17 % in the IMHS group. Non-union (p < 0.001) and increasing lag screw length (p < 0.02) were identified as risk factors for implant fracture and other mechanical complications. The reverse oblique fracture pattern (AO 31 A3.1) was associated with mechanical complications only (p < 0.01). The cumulative survival rates without revision for the TFNA, InterTAN, IMHS groups were 97.8 %, 95.5 % and 87.9 % respectively at 2.5 years. DISCUSSION: The rates of implant fracture were comparable between the three nailing systems. The TFNA provides effective fixation for proximal femur fractures using a traditional screw without cement augmentation. The TFNA was associated with an overall reduction in mechanical complications compared to the InterTAN and IMHS. Previously reported mechanical complications associated with IM Nails may relate to older device designs.

Predictive Value of Prognostic Nutritional Index for Early Postoperative Mobility in Elderly Patients with Pertrochanteric Fracture Treated with Intramedullary Nail Osteosynthesis.

BACKGROUND: Early postoperative mobilization is essential for orthogeriatric patients. The prognostic nutritional index (PNI) is widely used to evaluate nutritional status. This study sought to investigate the predictive value of PNI for early postoperative mobility in patients with pertrochanteric femur fractures. MATERIALS AND METHODS: This study included 156 geriatric patients with pertrochanteric femur fractures treated with TFN-Advance™ (DePuy Synthes, Raynham, MA, USA). Mobility was evaluated on the third postoperative day and by discharge. Stepwise logistic regression analyses were performed to evaluate the association significance of PNI with postoperative mobility together with comorbidities. The optimal PNI cut-off value for mobility was analyzed using the receiver operating characteristic (ROC) curve. RESULTS: Three days postoperatively, PNI was an independent predictor of mobility (OR: 1.14, 95% CI: 1.07-1.23, p < 0.01). By discharge, it was found that PNI (OR: 1.18, 95% CI: 1.08-1.30, p < 0.01) and dementia (OR: 0.17, 95% CI: 0.07-0.40, p < 0.001) were significant predictors. PNI correlated weakly with age (r = -0.27, p < 0.001). The PNI cut-off value for mobility on the third postoperative day was 38.1 (specificity = 78.5%, sensitivity = 63.6%). CONCLUSIONS: Our findings indicate that PNI is an independent predictor of early postoperative mobility in geriatric patients with pertrochanteric femur fractures treated with TFNA™.

Reduced cutout for reverse oblique intertrochanteric hip fractures treated with trochanteric fixation advanced (TFN-A) nail compared to the short gamma-3 nail.

BACKGROUND: Reverse oblique fractures (AO/OTA 31-A3) account for 5-23% of all intertrochanteric fractures and are challenging to manage. The Gamma 3-Proximal Femoral Nail (GPFN) and the Trochanteric Fixation Nail Advanced (TFNA) are two common cephalomedullary systems used to treat this fracture. No study has reported on outcomes with the TFN-A for reverse oblique fractures. This study aimed to compare outcomes and complication rates in patients with reverse oblique fractures, treated with either TFNA or GPFN. PATIENTS AND METHODS: A total of 203 patients with reverse oblique fractures (137 in the GPFN group and 66 in the TFNA group), were treated in our institution between June 2010 and May 2019. Data was collected on postoperative radiological variables including screw or blade location, and tip-apex distance (TAD). Data were also collected for non-orthopaedic complication rates and orthopaedic complications. A sub-group analysis was additionally performed for different nail lengths. RESULTS: We found no significant difference in the overall rate of complications and revisions between the two groups. Patients treated with the 235 mm TFN-A nail sustained lower rates of cutout, compared to 180 mm GPFN (GPFN: 6% TFN-A: 0%, p = 0.043). The frequency of revision surgeries and malunions/non-unions did not differ significantly between the two groups and additionally showed no difference in the subgroup analysis. CONCLUSION: The 235 mm TFN-A was associated with lower rates of cut-out compared to the short GPFN for reverse oblique intertrochanteric fractures. Future well-designed prospective studies are warranted to investigate the role of the TFN-A in improving outcomes for such fractures.

Experimental magnesium phosphate cement paste increases torque of trochanteric fixation nail advanced™ blades in human femoral heads.

BACKGROUND: The use of polymethylmethacrylate cement for in-situ implant augmentation has considerable disadvantages: it is potentially cytotoxic, exothermic and non-degradable. Therefore, the primary aim of this study was to develop a magnesium phosphate cement which meets the requirements for in-situ implant augmentation as an alternative. Secondly, this experimental cement was compared to commercial bone cements in a biomechanical test set-up using augmented femoral head blades. METHODS: A total of 40 human femoral heads were obtained from patients who underwent total hip arthroplasty. After bone mineral density was quantified, specimens were assigned to four treatment groups. A blade of the Trochanteric Fixation Nail Advanced™ was inserted into each specimen and augmented with either Traumacem™ V+, Paste-CPC, the experimental magnesium phosphate cement or no cement. A rotational load-to-failure-test (0° to 90°) was performed. FINDINGS: A conventional two-component magnesium phosphate cement failed in-situ implant augmentation consistently due to filter pressing. Only a glycerol-based magnesium phosphate paste was suitable for the augmentation of femoral head blades. While the blades augmented with Traumacem™ V+ yielded the highest maximum torque overall (22.1 Nm), the blades augmented with Paste-CPC and the magnesium phosphate paste also showed higher maximum torque values (15.8 and 12.8 Nm) than the control group (10.8 Nm). INTERPRETATION: This study shows for the first time the development of a degradable magnesium phosphate cement paste which fulfills the requirements for in-situ implant augmentation. Simultaneously, a 48% increase in stability is demonstrated for a scenario where implant anchorage is difficult in osteoporotic bone.

Prospective randomized multicenter noninferiority clinical trial evaluating the use of TFN-advancedTM proximal femoral nailing system (TFNA) for the treatment of proximal femur fracture in a Chinese population.

PURPOSE: To evaluate whether the 24-weeks postoperative fracture union rate for the investigational TFNA intramedullary nail was non-inferior compared to the control product PFNA-II. METHODS: The study was a prospective, randomized, single-blind, noninferiority dual-arm study drawing from 9 trauma centers across China, between November 2018 and September 2020, with follow-up measurements at 24 weeks after internal fixation. The full analysis data set (FAS [Intent-to-Treat]) was analyzed and is summarized here. The primary outcome was fracture union rate, a composite score combining clinical and radiographic assessment. Secondary endpoints comprised (a) clinical outcomes including (1) SF-12, (2) Harris Hip, and (3) EQ-5D Scores, (b) radiographic incidence of complications such as loosening or cut-out requiring revision, (c) revision rates, (d) reoperation rates, and (e) adverse events, including 24-weeks revision and reoperation rates. RESULTS: Both TFNA and PFNA-II group fracture healing rates were 100% at 24 weeks; TFNA was therefore shown to be non-inferior to PFNA-II. With baseline data matched in all parameters except age in both the TFNA and PFNA-II groups, comparisons of union rates, SF-12, Harris Hip, and EQ-5D Scores yielded p values > 0.05 indicating no significant difference between the two groups, further supporting the noninferiority of TFNA. In both groups, revision and re-operation rates were 0, and the incidences of serious adverse events were 19.4% and 17.4%, respectively. CONCLUSION: In terms of fracture union rate at 24 weeks, the DePuy Synthes Trochanteric Fixation Nail Advanced (TFNA) was not inferior to the marketed Proximal Femoral Nail Antirotation (PFNA-II) device produced by the same manufacturer. Secondary and safety outcomes showed no significant differences between the two groups. REGISTRATION: Registration was completed at ClinicalTrials.gov NCT03635320.

Use of Virtual Reality in the Education of Orthopaedic Procedures: A Randomised Control Study in Early Validation of a Novel Virtual Reality Simulator.

Background Virtual reality (VR) simulation is a potential solution to the barriers surgical trainees are facing. There needs to be validation for its implementation within current training. We aimed to compare VR simulation to traditional methods in acquiring surgical skills for a TFN-ADVANCED™ Proximal Femoral Nailing System (TFNA; DePuy Synthes, Auckland, New Zealand) femoral nailing system. Methods Thirty-one surgical trainees were randomised to two groups: traditional-training group (control group) and a VR-training group (intervention group) for insertion of a short cephalomedullary TFNA nail. Both groups then inserted the same TFNA system into saw-bone femurs. Surveys evaluated validity of the relevant activities, perception of simulation, confidence, stress and anxiety. The primary outcomes were tip-apex distance (TAD) and user anxiety/confidence levels. Secondary outcomes included number of screw- and nail-guidewire insertion attempts, the time taken to complete and user validity of the VR system. Results There was no statistical difference in TAD between the intervention and control groups (9mm vs 15mm, p=0.0734). The only TAD at risk of cut-out was in the control group (25mm). There was no statistical difference in time taken (2547.5ss vs 2395ss, p=0.668), nail guide-wire attempts (two for both groups, p=0.355) and screw guide-wire attempts (one for both groups, p=0.702). The control group versus intervention had higher anxiety levels (50% vs 33%) and had lower confidence (61% vs 84%). Interpretation There was no objective difference in performance on a saw-bone model between groups. However, this VR simulator resulted in more confidence and lower anxiety levels whilst performing a simulated TFNA. Whilst further studies with larger sample sizes and exploration of transfer validity to the operating theatre are required, this study does indicate potential benefits of VR within surgical training.

Case report: unique failure of a Synthes TFNA fenestrated lag screw in a peritrochanteric nonunion.

Background: Intertrochanteric femur fractures are a common orthopaedic injury that are often treated surgically. Cephalomedullary nails (CMN) are frequently the implant of choice for intertrochanteric femur fractures, resulting in low complication rates. Implant failure is a rare but reported complication. Common locations of failure include the proximal nail aperture, distal screw holes, and implant shaft. In this case report, we describe a CMN failure pattern through fenestrated cephalic screw holes. Case: A 70-year-old female sustained an OTA 31A-2.2 peritrochanteric fracture during a motor vehicle collision. She was treated the following day with a Synthes Trochanteric Fixation Nail-Advanced CMN utilizing a fenestrated cephalic screw. There were no intraoperative complications. She was made non-weight bearing for 8 weeks after the procedure due to ipsilateral foot fractures. At 6 months follow-up she was noted to have a delayed union. 11 months postoperatively she suffered a ground level fall and the cephalic lag screw failed through its fenestrations, resulting in varus collapse of her fracture at the femoral neck. The patient then underwent nail extraction and salvage total hip arthroplasty. Conclusion: Cephalomedullary nail implant failure is presented with implant fracture propagation through a fenestrated cephalic screw. Cephalomedullary lag screw failure is rare and can be difficult to manage. It is important to monitor new implants for unique failure mechanisms.

Effect of Tetrahedral Framework Nucleic Acids on Neurological Recovery via Ameliorating Apoptosis and Regulating the Activation and Polarization of Astrocytes in Ischemic Stroke.

Astrocytes, as the most plentiful subtypes of glial cells, play an essential biphasic function in ischemic stroke (IS). However, although having beneficial effects on stroke via promoting nerve restoration and limiting lesion extension, astrocytes can unavoidably cause exacerbated brain damage due to their participation in the inflammatory response. Therefore, seeking an effective and safe drug/strategy for protecting and regulating astrocytes in stroke is urgent. Here, we employ tetrahedral framework nucleic acid (tFNA) nanomaterials for astrocytes in stroke, considering their excellent biological properties and outstanding biosafety. In vitro, tFNA can inhibit calcium overload and ROS regeneration triggered by oxygen-glucose deprivation/reoxygenation (OGD/R), which provides a protective effect against astrocytic apoptosis. Furthermore, morphological changes such as hyperplasia and hypertrophy of reactive astrocytes are restrained, and the astrocytic polarization from the proinflammatory A1 phenotype to the neuroprotective A2 phenotype is facilitated by tFNA, which further alleviates cerebral infarct volume and facilitates the recovery of neurological function in transient middle cerebral artery occlusion (tMCAo) rat models. Moreover, the TLRs/NF-κB signaling pathway is downregulated by tFNA, which may be the potential mechanism of tFNA for protecting astrocytes in stroke. Collectively, we demonstrate that tFNA can effectively mediate astrocytic apoptosis, activation, and polarization to alleviate brain injury, which represents a potential intervention strategy for IS.

Self-assembled tetrahedral framework nucleic acid mediates tumor-associated macrophage reprogramming and restores antitumor immunity.

There is increasing interest in depleting or repolarizing tumor-associated macrophages (TAMs) to generate a proinflammatory effect. However, TAMs usually display an immunosuppressive M2-like phenotype in the tumor microenvironment. Apparently, developing a macrophage-targeting delivery system with immunomodulatory agents is urgent. In this study, an efficient siRNA and CpG ODNs delivery system (CpG-siRNA-tFNA) was prepared with nucleic acid stepwise self-assembled. The tFNA composed of CpG ODNs and siRNA showed a higher stability and an enhanced cellular uptake efficiency. Moreover, the CpG-siRNA-tFNA effectively reprogrammed TAMs toward M1 phenotype polarization with increased proinflammatory cytokine secretion and NF-κB signal pathway activation, which triggers dramatic antitumor immune responses. Additionally, the CpG-siRNA-tFNA exhibited superior antitumor efficacy in a breast cancer xenograft mouse model without obvious systemic side effects. Taken together, CpG-siRNA-tFNA displayed greatly antitumor effect by facilitating TAM polarization toward M1 phenotypes in favor of immunotherapy. Hence, we have developed an efficient therapeutic strategy with immunomodulatory agents for clinical applications.