Evaluation of treatment processes in childhood fifth metacarpal bone (Boxer) fractures with QuickDASH scoring system.

OBJECTIVE: Metacarpal fractures are one of the most common orthopedic injuries seen in emergency departments. Despite this, only a few data have been published about the epidemiology of metacarpal fractures. Simple radiographs are the standard imaging modality used to diagnose boxer fractures and determine the degree of angulation. Fractures and angulations should be identified by anteroposterior and lateral radiographs. The aim of this study was to follow the healing after closed reduction of fifth metacarpal neck fractures in a pediatric population using the QuickDASH score to determine whether it results in clinically significant improvement. SUBJECTS AND METHODS: Between 2020 and 2022, our clinical record database for all metacarpal fractures treated at our institution was searched retrospectively every month. Children aged 18 years and younger with fifth metacarpal neck fractures treated with closed reduction and immobilization in our tertiary care emergency clinic were retrospectively reviewed. RESULTS: 52 pediatric patients were included in the study. The mean age at the time of injury was 14.04 years (SD=2.10, range=10-18 years). 92.30% (n=48) of the patients were male, and 7.70% (n=4) were female. CONCLUSIONS: Accurate diagnosis and appropriate treatment are crucial in the management of childhood fifth metacarpal fractures to ensure proper healing, prevent long-term complications, and facilitate optimal functional recovery.

IL-17RA Signaling in Prx1+ Mesenchymal Cells Influences Fracture Healing in Mice.

Fracture healing is a complex series of events that requires a local inflammatory reaction to initiate the reparative process. This inflammatory reaction is important for stimulating the migration and proliferation of mesenchymal progenitor cells from the periosteum and surrounding tissues to form the cartilaginous and bony calluses. The proinflammatory cytokine interleukin (IL)-17 family has gained attention for its potential regenerative effects; however, the requirement of IL-17 signaling within mesenchymal progenitor cells for normal secondary fracture healing remains unknown. The conditional knockout of IL-17 receptor a (Il17ra) in mesenchymal progenitor cells was achieved by crossing Il17raF/F mice with Prx1-cre mice to generate Prx1-cre; Il17raF/F mice. At 3 months of age, mice underwent experimental unilateral mid-diaphyseal femoral fractures and healing was assessed by micro-computed tomography (µCT) and histomorphometric analyses. The effects of IL-17RA signaling on the osteogenic differentiation of fracture-activated periosteal cells was investigated in vitro. Examination of the intact skeleton revealed that the conditional knockout of Il17ra decreased the femoral cortical porosity but did not affect any femoral trabecular microarchitectural indices. After unilateral femoral fractures, Il17ra conditional knockout impacted the cartilage and bone composition of the fracture callus that was most evident early in the healing process (day 7 and 14 post-fracture). Furthermore, the in vitro treatment of fracture-activated periosteal cells with IL-17A inhibited osteogenesis. This study suggests that IL-17RA signaling within Prx1+ mesenchymal progenitor cells can influence the early stages of endochondral ossification during fracture healing.

Radiographic outcomes and non-union factor analysis in fragmentary segmental femoral shaft fractures (AO/OTA 32C3) treated with reamed antegrade nailing.

This study retrospectively assessed radiographic outcomes and risk factors associated with non-union in femoral shaft fragmentary segmental fractures (AO/OTA 32C3) treated with reamed antegrade intra-medullary nailing. Radiological outcomes, including union and alignment, were evaluated. The risk factors for non-union were investigated, including demographics and treatment-related characteristics, such as the number of interlocking screws, segmentation length, main third fragment length, distance of the main third fragment, width ratio and exposed nail length in one cortex from immediate post-operative radiographs. Multivariate logistic regression was used for statistical analysis. Among 2295 femoral shaft fracture patients from three level-1 trauma centers, 51 met the inclusion criteria. The radiological union was achieved in 37 patients (73%) with a mean union time of 10.7 ± 4.8 months. The acceptable axial alignment was observed in 30 patients (59%). Multiple logistic regression analysis identified only exposed nail length as a significant risk factor for non-union (odds ratio: 1.599, p = 0.003) and the cut-off value was 19.1 mm (sensitivity, 0.786; specificity, 0.811). The study revealed high rates of non-union (27%) and malalignment (41%). Therefore, patients who underwent intramedullary nailing with an exposed nail length greater than 19.1 mm or about twice the nail diameter should be cautioned of the potential non-union.

Fracture healing on non-union fracture model promoted by non-thermal atmospheric-pressure plasma.

Non-thermal atmospheric-pressure plasma (NTAPP) is attracting widespread interest for use in medical applications. The tissue repair capacity of NTAPP has been reported in various fields; however, little is known about its effect on fracture healing. Non-union or delayed union after a fracture is a clinical challenge. In this study, we aimed to investigate how NTAPP irradiation promotes fracture healing in a non-union fracture model and its underlying mechanism, in vitro and in vivo. For the in vivo study, we created normal and non-union fracture models in LEW/SsNSlc rats to investigate the effects of NTAPP. To create a fracture, a transverse osteotomy was performed in the middle of the femoral shaft. To induce the non-union fracture model, the periosteum surrounding the fracture site was cauterized after a normal fracture model was created. The normal fracture model showed no significant difference in bone healing between the control and NTAPP-treated groups. The non-union fracture model demonstrated that the NTAPP-treated group showed consistent improvement in fracture healing. Histological and biomechanical assessments confirmed the fracture healing. The in vitro study using pre-osteoblastic MC3T3-E1 cells demonstrated that NTAPP irradiation under specific conditions did not reduce cell proliferation but did enhance osteoblastic differentiation. Overall, these results suggest that NTAPP is a novel approach to the treatment of bone fractures.

Human nonunion tissues display differential gene expression in comparison to physiological fracture callus.

The healing of bone fractures can become aberrant and lead to nonunions which in turn have a negative impact on patient health. Understanding why a bone fails to normally heal will enable us to make a positive impact in a patient's life. While we have a wealth of molecular data on rodent models of fracture repair, it is not the same with humans. As such, there is still a lack of information regarding the molecular differences between normal physiological repair and nonunions. This study was designed to address this gap in our molecular knowledge of the human repair process by comparing differentially expressed genes (DEGs) between physiological fracture callus and two different nonunion types, hypertrophic (HNU) and oligotrophic (ONU). RNA sequencing data revealed over ∼18,000 genes in each sample. Using the physiological callus as the control and the nonunion samples as the experimental groups, bioinformatic analyses identified 67 and 81 statistically significant DEGs for HNU and ONU, respectively. Out of the 67 DEGs for the HNU, 34 and 33 were up and down-regulated, respectively. Similarly, out of the 81 DEGs for the ONU, 48 and 33 were up and down-regulated, respectively. Additionally, we also identified common genes between the two nonunion samples; 8 (10.8 %) upregulated and 12 (22.2 %) downregulated. We further identified many biological processes, with several statistically significant ones. Some of these were related to muscle and were common between the two nonunion samples. This study represents the first comprehensive attempt to understand the global molecular events occurring in human nonunion biology. With further research, we can perhaps decipher new molecular pathways involved in aberrant healing of human bone fractures that can be therapeutically targeted.

Increased ß2-adrenergic signaling promotes fracture healing through callus neovascularization in mice.

Traumatic brain injury (TBI) leads to skeletal changes, including bone loss in the unfractured skeleton, and paradoxically accelerates healing of bone fractures; however, the mechanisms remain unclear. TBI is associated with a hyperadrenergic state characterized by increased norepinephrine release. Here, we identified the ß2-adrenergic receptor (ADRB2) as a mediator of skeletal changes in response to increased norepinephrine. In a murine model of femoral osteotomy combined with cortical impact brain injury, TBI was associated with ADRB2-dependent enhanced fracture healing compared with osteotomy alone. In the unfractured 12-week-old mouse skeleton, ADRB2 was required for TBI-induced decrease in bone formation and increased bone resorption. Adult 30-week-old mice had higher bone concentrations of norepinephrine, and ADRB2 expression was associated with decreased bone volume in the unfractured skeleton and better fracture healing in the injured skeleton. Norepinephrine stimulated expression of vascular endothelial growth factor A and calcitonin gene-related peptide-α (αCGRP) in periosteal cells through ADRB2, promoting formation of osteogenic type-H vessels in the fracture callus. Both ADRB2 and αCGRP were required for the beneficial effect of TBI on bone repair. Adult mice deficient in ADRB2 without TBI developed fracture nonunion despite high bone formation in uninjured bone. Blocking ADRB2 with propranolol impaired fracture healing in mice, whereas the ADRB2 agonist formoterol promoted fracture healing by regulating callus neovascularization. A retrospective cohort analysis of 72 patients with long bone fractures indicated improved callus formation in 36 patients treated with intravenous norepinephrine. These findings suggest that ADRB2 is a potential therapeutic target for promoting bone healing.

[Treatment of irreducible intertrochanteric femoral fracture in elderly by folding top technique combined with right-angle pliers prying and pulling under G-arm X-ray fluoroscopy].

Objective: To explore the effectiveness of irreducible intertrochanteric femoral fracture in the elderly by treating with folding top technique and right-angle pliers prying and pulling under G-arm X-ray fluoroscopy. Methods: The clinical data of 74 elderly patients with irreducible intertrochanteric femoral fracture admitted between February 2016 and December 2022 and met the selection criteria were retrospectively analyzed. Among them, 38 cases were treated with folding top technique combined with right-angle pliers prying and pulling under G-arm X-ray fluoroscopy and intramedullary nailing fixation (study group), and 36 cases were treated with limited open reduction combined with other reduction methods and intramedullary nailing fixation (control group). There was no significant difference in baseline data between the two groups, such as age, gender, cause of injury, affected side and classification of fractures, complicated medical diseases, and time from injury to operation ( P>0.05). The operation time, intraoperative blood loss, hospital stay, fracture reduction time, fracture healing time, and complications of the two groups were recorded and compared. The quality of fracture reduction was evaluated by Baumgaertner et al. and Chang et al. fracture reduction standards. Results: Patients in both groups were followed up 10-14 months, with an average of 12 months. The operation time and intraoperative blood loss in the study group were significantly less than those in the control group ( P<0.05), there was no significant difference in hospital stay between the two groups ( P>0.05). At 2 days after operation, according to the fracture reduction standards of Baumgaertner et al. and CHANG Shimin et al., the quality of fracture reduction in the study group was better than that in the control group, and the fracture reduction time in the study group was shorter than that in the control group, with significant differences ( P<0.05). After operation, the fractures of the two groups all healed, and there was no significant difference in healing time between the two groups ( P>0.05). During the follow-up, there was no complication such as incision infection, internal fixation failure, deep venous thrombosis of lower limbs, intramedullary nail breakage, spiral blade cutting, or hip varus in the two groups, except for 2 cases of coxa vara in the control group. Conclusion: For the irreducible intertrochanteric femoral fracture, using folding top technique combined with right-angle pliers prying and pulling under G-arm X-ray fluoroscopy can obviously shorten the operation time, reduce the intraoperative blood loss, and improve the quality of fracture reduction.

Mechanosensitive protein polycystin-1 promotes periosteal stem/progenitor cells osteochondral differentiation in fracture healing.

Background: Mechanical forces are indispensable for bone healing, disruption of which is recognized as a contributing cause to nonunion or delayed union. However, the underlying mechanism of mechanical regulation of fracture healing is elusive. Methods: We used the lineage-tracing mouse model, conditional knockout depletion mouse model, hindlimb unloading model and single-cell RNA sequencing to analyze the crucial roles of mechanosensitive protein polycystin-1 (PC1, Pkd1) promotes periosteal stem/progenitor cells (PSPCs) osteochondral differentiation in fracture healing. Results: Our results showed that cathepsin (Ctsk)-positive PSPCs are fracture-responsive and mechanosensitive and can differentiate into osteoblasts and chondrocytes during fracture repair. We found that polycystin-1 declines markedly in PSPCs with mechanical unloading while increasing in response to mechanical stimulus. Mice with conditional depletion of Pkd1 in Ctsk+ PSPCs show impaired osteochondrogenesis, reduced cortical bone formation, delayed fracture healing, and diminished responsiveness to mechanical unloading. Mechanistically, PC1 facilitates nuclear translocation of transcriptional coactivator TAZ via PC1 C-terminal tail cleavage, enhancing osteochondral differentiation potential of PSPCs. Pharmacological intervention of the PC1-TAZ axis and promotion of TAZ nuclear translocation using Zinc01442821 enhances fracture healing and alleviates delayed union or nonunion induced by mechanical unloading. Conclusion: Our study reveals that Ctsk+ PSPCs within the callus can sense mechanical forces through the PC1-TAZ axis, targeting which represents great therapeutic potential for delayed fracture union or nonunion.

Comparative Outcomes of Elastic Stable Intramedullary Nailing vs. Plate Fixation in Pediatric Femoral Shaft Fractures. A Prospective Study.

BACKGROUND: Pediatric femoral fractures are common in emergency rooms, with treatment options varying by age. This study compares elastic stable intramedullary nailing (ESIN) and plate fixation for diaphyseal femoral fractures in children aged 5-10. MATERIAL AND METHODS: Conducted at Al-Kindi Teaching Hospital, Baghdad, from December 2017 to December 2019, this prospective study included 32 children with closed transverse diaphyseal femoral fractures. Patients were divided into two groups: 16 treated with ESIN (Group 1) and 16 with plate fixation (Group 2). Criteria excluded comminuted, open, or pathological fractures. RESULTS: Group 1 had a mean age of 7.1 years and weight of 23.7 kg; Group 2 had a mean age of 7.8 years and weight of 30.9 kg. ESIN resulted in shorter operative times (58.4 minutes), earlier weight-bearing, and quicker fracture union (8.8 weeks) compared to plate fixation (76.3 minutes, 11.9 weeks). Blood loss was significantly less in Group 1 (32.8 ml) versus Group 2 (205.0 ml). No significant differences in wound healing or leg length discrepancies were observed. CONCLUSIONS: 1. Our study indicates a preference for Elastic Stable Intramedullary Nailing (ESIN) over plate fixation for pediatric femoral shaft fractures in children aged 5-10 years. 2. ESIN is associated with shorter operative times and faster commencement of weight-bearing, critical in pediatric recovery. 3. While ESIN is generally preferable, plate fixation may be better suited in certain clinical scenarios, emphasizing the importance of personalized treatment. 4. Based on our findings, ESIN is recommended for treating transverse diaphyseal femur fractures in the specified pediatric age group. 5. Recommends further studies, including randomized controlled trials, for a more comprehensive understanding of these treatments' long-term outcomes.

SVF Therapy of Delayed Fracture Union in Patients with Multiple Combat Injury. Case Report.

Delayed union of fractures is one of the most frequent complications in orthopedic practice, especially in polytrauma patients. With the development of new methods of regenerative medicine, including the use of adipose derived stromal cells as a component of the stromal-vascular fraction (SVF), new possibilities for conservative treatment of this problem have emerged. This article presents a clinical case of conservative treatment of delayed union of a radial bone fracture using local SVF injections. In the fracture space, SVF with PRP creates a pool of cells that could differentiate towards surrounding tissue, releases various inducers of tissue growth and, via an indirect chemotactic effect on receptors, mobilizes the body's own resources and creates conditions for angiogenesis and trophism in the injured segment. In the patient with delayed consolidation after SFV-therapy, progress in clinical and radiological dynamics was noted with complete healing within 7 months. The positive clinical result provides a basis for further study and implementation in practice.

Is Elastic Stable Intramedullary Nailing a Viable Treatment Option for Diaphyseal Fractures of the Humerus in Adults? A 29-case Series Prospective Study.

BACKGROUND: Humerus shaft fractures are common in orthopaedic practice. The emphasis in treatment has shifted from prolonged immobilisation to early mobilisation and internal fixation when needed for a quicker return to normal function. Internal fixation methods include plate osteosynthesis and intramedullary nailing. This study specifically evaluated the effectiveness of flexible intramedullary nails in treating diaphyseal humeral fractures. MATERIAL AND METHODS: Between April 2007 and January 2010, Alexandria University Hospital treated 29 patients (21 males, 8 females) with diaphyseal humeral fractures. Treatment involved closed reduction and percutaneous fixation using two flexible nails. Patients, aged 17 to 65 with a mean age of 32, were included if they did not have pathological fractures, were above 16 years old, and were medically suitable. Causes included pedestrian vehicle accidents (17 cases) and falls or sports-related activities (12 cases). Surgical intervention occurred 1 to 8 days after the injury. RESULTS: Between April 2007 and January 2010, Alexandria University Hospital treated 29 patients (21 males, 8 females) for diaphyseal humeral fractures using closed reduction and percutaneous fixation with two flexible nails. Patients, aged 17 to 65, were monitored for an average of 18 months. Radiographic assessments showed complete union in nineteen fractures within 13 to 21 weeks. One patient experienced non-union but was successfully treated with bone grafting and plating. There were no significant intraoperative complications. Notably, four patients with preoperative radial nerve injuries recovered within 6 to 8 weeks. Evaluation using the Stewart and Hundley Scoring technique showed excellent outcomes for 60% of patients, good outcomes for 30%, fair outcomes for 5%, and poor outcomes for 5%. CONCLUSIONS: 1.The Elastic Stable Intramedullary Nailing (ESIN) technique shows promise in the treatment of humeral shaft fractures. 2. However, the success of treatment may depend on various factors, including patient age, fracture characteristics, and the presence of complications such as open fractures and radial nerve palsy. 3. Careful consideration of these factors is necessary when selecting a treatment approach for humeral shaft fractures.

Polytherapy versus monotherapy in the treatment of tibial non-unions: a retrospective study.

BACKGROUND: Treating tibial non-unions efficiently presents a challenge for orthopaedic trauma surgeons. The established gold standard involves implanting autologous bone graft with adequate fixation, but the addition of biologicals according to the so-called diamond concept has become increasingly popular in the treatment of non-unions. Previous studies have indicated that polytherapy, which involves implanting mesenchymal stem cells, bioactive factors and osteoconductive scaffolds, can improve bone healing. This study aims to evaluate the efficacy of polytherapy compared with monotherapy in treating tibial non-unions of varying severity. MATERIALS AND METHODS: Data from consecutive tibial non-unions treated between November 2014 and July 2023 were retrospectively analysed. The Non Union Scoring System (NUSS) score before non-union surgery, and the Radiographic Union Score for Tibial fractures (RUST), scored at 1, 3, 6, 9, 12 and 18 months post-surgery, were recorded. Initially, a comparison was made between the polytherapy and monotherapy groups. Subsequently, patients receiving additional surgical non-union treatment were documented, and the frequency of these treatments was tallied for a subsequent per-treatment analysis. RESULTS: A total of 34 patients were included and divided into a polytherapy group (n = 15) and a monotherapy group (n = 19). The polytherapy group demonstrated a higher NUSS score (44 (39, 52) versus 32 (29, 43), P = 0.019, z = -2.347) and a tendency towards a higher success rate (93% versus 68%, P = 0.104) compared with the monotherapy group. For the per-treatment analysis, 44 treatments were divided into the polytherapy per-treatment group (n = 20) and the monotherapy per-treatment group (n = 24). The polytherapy per-treatment group exhibited a higher NUSS score (48 (43, 60) versus 38 (30, 50), P = 0.030, z = -2.173) and a higher success rate (95% versus 58%, P = 0.006) than the monotherapy per-treatment group. Within the monotherapy per-treatment group, the NUSS score displayed excellent predictive performance (AUC = 0.9143). Setting the threshold value at 48, the sensitivity and specificity were 100.0% and 70.0%, respectively. CONCLUSIONS: Polytherapy is more effective than monotherapy for severe tibial non-unions, offering a higher success ratio. The NUSS score supports decision-making in treating tibial non-unions. LEVEL OF EVIDENCE: Level III.

Effects of Focal Cerebellar Injury on Fracture Healing and Oxidative Stress in Rat Model: An Experimental Animal Study.

AIM: To examine the effect of cerebellar damage on the process of fracture healing. MATERIAL AND METHODS: A total of forty-two male rats were selected at random and subsequently allocated into three distinct groups. The experimentals were divided into two subgroups within each group, with the intention of sacrificing them during the third and sixth weeks. Group 1 had isolated femoral fracture, Group 2 had femoral fracture after craniotomy, and Group 3 had femoral fracture accompanying cerebellar injury after craniotomy. Left femoral fractures in rats in all groups were treated using an intramedullary Kirschner wire. Radiological, histological, and biochemical evaluations were conducted at 3 and 6 weeks to assess the processes of fracture healing. To determine the effects of fracture healing and cerebellar injury on oxidant-antioxidant systems, catalase (CAT), malondialdehyde, superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities were measured. RESULTS: Between the time frame of 3 to 6 weeks, Group 3 had higher radiography scores, alkaline phosphatase levels, callus/ diaphyse ratio, callus improvement, and bone mineral density in comparison to the other groups. The activity of SOD was found to be statistically negligible in all groups, suggesting that SOD does not have a substantial impact on fracture healing in cerebellar injury. However, notable increases in the activity of GPx and CAT enzymes were observed, showing their considerable involvement in the process of fracture healing. CONCLUSION: Cerebellar injury reduces the oxidative stress in the fracture area and contributes positively to fracture healing by means of radiologically, biochemically and histopathologically.

Plate augmentation and hybrid bone grafting are effective treatments for atrophic nonunion of the femur with the original intramedullary nail retained in situ.

The purpose of this study is to evaluate the efficacy of plate augmentation and hybrid bone grafting for treating atrophic nonunion of the femur with original intramedullary nail retained in situ.In this study, 36 patients with atrophic nonunion of the femur who underwent surgery using the technique of plate augmentation and a hybrid bone grafting while retaining the original intramedullary nail in situ in Xi'an Honghui Hospital from January 2019 to December 2021 were enrolled. 28 patients who met the inclusion and exclusion criteria were ultimately included in the study. These 28 patients, consisting of 20 males and 8 females with a mean age of 38 years, were evaluated based on factors such as operation time, intraoperative blood loss, the average hospitalization days. Additionally, the results and function of these patients were evaluated by union time, Wu's scores of limb function and incidence of serious complications.All 28 patients achieved bone union at the 12 month follow-up, with an average follow-up time of 14.6 ± 4.2 months.The average operation time was 68.3 ± 11.2 min, and the average intraoperative blood loss was 140 ± 22.6 ml. Patients were hospitalized for an average of 5.8 ± 1.1 days. Full clinical and radiological bone union was achieved on average at 5.1 ± 1.9 months. The mean value of Wu's scores at the 12 month follow-up was significantly higher than before the operation. Limb function was excellent in 27 patients and good in one patient at the 12 month follow-up. However, five patients experienced the lower limb vein thrombosis, including one deep vein thrombosis and four lower limb intermuscular vein thromboses. One patient had a superficial infections of the surgical incision site, while three patients reported pain and numbness where their iliac bone graft was extracted at the 12 month follow-up. The technique of plate augmentation and hybrid bone grafting, combined with retaining the original intramedullary nail in situ has been shown to be a safe, effective, simply and standardizable practice for treating atrophic femoral nonunion with an intact original IMN fixation.

Wound infection and healing in minimally invasive plate osteosynthesis compared with intramedullary nail for distal tibial fractures: A meta-analysis.

To systematically explore the effects of minimally invasive plate osteosynthesis (MIPO) versus intramedullary nail (IMN) on wound infection and wound healing in patients with distal tibia fractures. A computerised search of PubMed, Web of Science, Cochrane Library, Embase, Wanfang, China Biomedical Literature Database (CBM) and China National Knowledge Infrastructure databases was performed, from their inception to October 2023, to identify relevant studies on the application of MIPO and IMN in patients with distal tibial fractures. The quality of the included literature was evaluated by two researchers based on inclusion and exclusion criteria, and basic information of the literature was collected, with wound infection, postoperative complications and wound healing time as the main indicators for analysis. Stata 17.0 software was applied for analysis. Overall, 23 papers and 2099 patients were included, including 1026 patients in the MIPO group and 1073 patients in the IMN group. The results revealed, when compared with IMN treatment, patients with distal tibia fractures who underwent MIPO treatment had a lower incidence of postoperative complications (OR = 0.33, 95% CI: 0.25-0.42, p < 0.001) and a shorter wound healing time (SMD = -1.00, 95% CI: -1.51 to -0.49, p < 0.001), but the incidence of postoperative wound infection was higher (OR = 2.01, 95% CI: 1.35-3.01, p = 0.001). Both MIPO and IMN are excellent treatments for distal tibia fractures. MIPO is effective in reducing the incidence of complications as well as shortening the time of wound healing time but increases the risk of wound infection. In clinical practice, surgeons can make individual choices based on the patient's wishes and proficiency in both techniques.

Femoral Shaft Fracture Developed Late-Onset Infection in 27 Years after Intramedullary Nailing: A Case Report.

Postoperative late-onset infections more than 1 year after intramedullary nail surgery for femoral shaft fractures are very rare. We show an extremely rare case of developed late-onset infection 27 years after surgery, report on risk factors for late-onset infection, and infer why the infection occurred.

Unique Spatial Transcriptomic Profiling of the Murine Femoral Fracture Callus: A Preliminary Report.

Fracture callus formation is a dynamic stage of bone activity and repair with precise, spatially localized gene expression. Metastatic breast cancer impairs fracture healing by disrupting bone homeostasis and imparting an altered genomic profile. Previous sequencing techniques such as single-cell RNA and in situ hybridization are limited by missing spatial context and low throughput, respectively. We present a preliminary approach using the Visium CytAssist spatial transcriptomics platform to provide the first spatially intact characterization of genetic expression changes within an orthopedic model of impaired fracture healing. Tissue slides prepared from BALB/c mice with or without MDA-MB-231 metastatic breast cancer cells were used. Both unsupervised clustering and histology-based annotations were performed to identify the hard callus, soft callus, and interzone for differential gene expression between the wild-type and pathological fracture model. The spatial transcriptomics platform successfully localized validated genes of the hard (Dmp1, Sost) and soft callus (Acan, Col2a1). The fibrous interzone was identified as a region of extensive genomic heterogeneity. MDA-MB-231 samples demonstrated downregulation of the critical bone matrix and structural regulators that may explain the weakened bone structure of pathological fractures. Spatial transcriptomics may represent a valuable tool in orthopedic research by providing temporal and spatial context.

[A prospective study on treatment of Sanders type â ¡ and â ¢ calcaneal fractures with interlocking intramedullary nail fixation system].

Objective: To explore the effectiveness of interlocking intramedullary nail fixation system for Sanders type Ⅱ and Ⅲ calcaneal fractures by comparing with open surgery. Methods: Forty patients (40 feet) with Sanders type Ⅱ and Ⅲ calcaneal fractures, who were admitted between May 2020 and December 2022 and met the selection criteria, were included in the study. They were randomly allocated into control group and minimally invasive group using a random number table method, with 20 cases in each group. The patients were treated with the interlocking intramedullary nail fixation system in the minimally invasive group and with steel plate internal fixation via a lateral L-shaped incision in the control group. There was no significant difference between the two groups ( P>0.05) in terms of gender, age, fracture classification and side, cause of injury, time from injury to admission, and preoperative width, length, height, Böhler angle, and Gissane angle of the calcaneus. The operation time, intraoperative blood loss, incision length, hospital stay, fracture healing time, incidence of complications, as well as pre- and post-operative imaging indicators (Böhler angle, Gissane angle, width, height, and length of the calcaneus) and American Orthopaedic Foot and Ankle Society (AOFAS) score of foot were recorded and compared between the two groups. Results: The incision length, operation time, and hospital stay of the minimally invasive group were significantly shorter than those of the control group, and the intraoperative blood loss significantly reduced ( P<0.05). All patients of the two groups were followed up, with the follow-up time of 8-12 months (mean, 10.2 months) in the minimally invasive group and 8-12 months (mean, 10.4 months) in the control group. No complication occurred in the minimally invasive group after operation. One case of incision epidermal necrosis and 1 case of traumatic arthritis occurred in the control group after operation. However, there was no significant difference in the incidence of complications between the two groups ( P>0.05). At last follow-up, the AOFAS score was significantly higher in the minimally invasive group than in the control group ( P<0.05). Imaging examination showed that the calcaneal fractures of the two groups healed, and there was no significant difference in healing time between the two groups ( P>0.05). Compared with preoperative conditions, the Böhler angle and Gissane angle of the calcaneus in the two groups significantly increased, the width narrowed, and the height and length increased at 3 days after operation and the last follow-up, with significant differences ( P<0.05). There was no significant difference between 3 days after operation and last follow-up ( P>0.05). There was no significant difference between the two groups at each time point ( P>0.05). Conclusion: The interlocking intramedullary nail fixation system in treatment of Sanders type Ⅱ and Ⅲ calcaneal fractures has the advantages of minimal trauma, shortened hospital stay, reliable fracture reduction and fixation, and satisfactory foot function recovery.

Topology optimization of embracing fixator considering bone remodeling to mitigate stress shielding effect.

The embracing fixator is one of the widely used internal fixation implants for bone fracture treatment. However, the stress shielding effect, a stress imbalance between the implant and bone caused by the mismatch in mechanical properties between them, is a significant and critical issue that may lead to treatment failure. Thus, it is of great importance to design the implant with an appropriate stiffness which can mitigate the stress shielding effect and provide the most favorable mechanical environment for bone healing and remodeling. To this end, a time-dependent topology optimization algorithm considering bone remodeling is proposed to optimize an embracing fixator used in the tibia fracture treatment. The change of callus density over time is simulated based on a bone remodeling model, and the callus density after a period of bone remodeling is selected to be the design objective to maximize. The design constraints include volume and the compliance of the whole fixation system. Meanwhile, the influence of the constraints on the regularity of material distribution of the optimized result is also studied. Besides, to test the effectiveness of the consideration of the bone remodeling in the embracing fixator design, a topology optimization concerning the minimization of the compliance of the entire system is also performed to make a comparison. Finally, the safety performance of optimized results considering bone remodeling is also verified by static analysis.

Advances in Hand Therapy: Best Practice in Conservative Management of Proximal Phalangeal Fractures in Children.

BACKGROUND: Proximal phalangeal fractures are one of the most commonly treated hand injuries in children. Conservative management of these fractures is often to splint for 5 weeks post injury, despite children presenting as clinically healed at 3 weeks post injury. Therefore, we investigated the effect of splinting for only 3 weeks in children who present with clinically healed proximal phalangeal fractures at 3 weeks compared with usual care. METHODS: Participants (n=80, aged 10.3 ±2.5 years) presenting to the Hand Clinic of a tertiary Children's Hospital in Sydney, Australia, were randomly allocated into a Current Protocol and a New Protocol group. Following were the inclusion criteria: aged between 5 and 16 years; present with an non-displaced or minimally displaced and stable fracture; no surgical intervention; assessed as clinically healed at 3-week visit. The primary outcome measure was total active motion (TAM) of the injured digit compared with the contralateral digit (deg), at 5 weeks post injury. Secondary outcome measures were grip strength, and a parent-reported questionnaire. Statistical analysis used χ 2 test and the absolute difference described by a 90% CI. The New Protocol was considered noninferior if the 90% CI overlap was > 20% of the Current Protocol. Analysis was by intention to treat. RESULTS: There was a 10% loss to follow up at 5 weeks (Current Protocol =4, New Protocol =4). All CIs between groups overlapped by >10%. TAM 90% CI for Current Protocol was 17.7 to 5.4 degrees and for the New Protocol was 4.7 to 1.6 degrees. CONCLUSIONS: A change in practice is warranted to cease immobilization for children with conservatively managed proximal phalangeal fractures who present as clinically healed at 3 weeks. Therapist assessment of fracture healing is an appropriate indicator for intervention and can be utilized in a therapist-led model of care. LEVEL OF EVIDENCE: Level 1-noninferiority randomized control trial with 2 parallel arms.