Epdemiology and Treatment of Pseudarthrosis of Long Bones in the Servce D Orthopedics-Traumatology of the University Hospital of Donka

Introduction: Pseudarthrosis (PSA) of the diaphysis of long bones still remains a current problem, despite improvements in the treatment of these fractures. Our study aims to study the epidemiological and therapeutic aspects of PSA of the diaphysis of long bones. Method: This retrospective work concerns 30 cases of non-union of the diaphysis of long bones treated in the orthopedic and trauma surgery department at Donka National Hospital, during a period of 18 months from January 1, 2019 to June 30, 2020. Results: We recruited 30 patients, 80% of whom were male, with an average age of 39.9 years. Public road accidents (AVP) represented the main cause of fractures of the diaphysis of long bones 87%, they were open in 25 cases or 83%. The fractures were located in the middle 1/3 of the diaphysis of the long bones in 50% of cases. Treatment of initial fractures was traditional in 21 cases, orthopedic in 2 cases and surgical in 7 cases. It was aseptic nonunion in 28 cases (93%) and septic nonunion in 2 cases. They were hypertrophic in 7 cases, slightly hypertrophic in 5 cases, oligotrophic in 11 cases, atrophic in 6 cases and with bone defect in 1 case. The treatment was based on osteosynthesis including 16 cases of screwed “PV” plate: 7 cases of centromedullary “ECM” nailing, 2 cases of external fixator, 1 case of broaching and 4 cases of Plastering. The results according to ASAMI criteria on an anatomical level were excellent in 19 cases, good in 3 cases and poor in 3 cases, with a union rate of 76%. And 5 patients undergoing consolidation. Conclusion: Based on the literature data and the experience of our department, the true treatment of PSA requires correct management of the initial fracture without forgetting the interest in preventing AVP which appears to be an element essential, making it possible to reduce the incidence of fractures of the diaphysis.

Intracortical chondroma of the metacarpal bone:A case report

BACKGROUND Intracortical chondroma of the metacarpal bone which could be painful is an extremely rare condition and previously only one case has been reported.Due to the similar physical features and appearance on clinical imaging,it is difficult to differentiate between intracortical chondroma and osteoid osteoma.Therefore,pathological examination is usually required to establish a definite diagnosis,which is often carried out only after tumor removal.In this study,we describe a case of intracortical chondroma which developed in the metacarpal bone and demonstrate the utility of magnetic resonance imaging(MRI).CASE SUMMARY We present a case of a 40-year-old man with intracortical chondroma of the metacarpal bone who was strongly suspected of having a tumor,and it was confirmed using contrast-enhanced MRI and successfully treated with curettage.MRI performed before tumor removal revealed signal intensity similar to that of the nidus of an osteoid osteoma.However,no abnormal intensity was observed in the bone or soft tissues surrounding the tumor.Such abnormalities on images would indicate the presence of soft-tissue inflammation,which are characteristics of osteoid osteoma.Furthermore,contrast-enhanced imaging revealed no increased enhancement of the areas surrounding the tumor.This is the first report to describe the contrast-enhanced MRI features of intracortical chondroma.This may serve as a guide for clinicians when intracortical chondroma is suspected.CONCLUSION The contrast-enhanced MRI was useful for the differential diagnosis of intracortical chondroma.

Salvage the Bones and The Not Yet: Environmental Crisis Writing of Post-Katrina Literature

After Hurricane Katrina in 2005,literary works related to such a crisis sprouted the southern America,which are known as Post-Katrina Literature.This thesis,taking Salvage the Bones and The Not Yet as examples,scrutinizes how writers respond to the Post-Katrina environmental crisis in different ways.In Salvage the Bones,Jesmyn Ward employs a biographical genre to record the Katrina disaster,thereby,writings serving as a way of healing the psychic trauma of the writer herself;and in The Not Yet,Moira Crone presents a post-natural world by the employment of the Cli-Fi genre.Both writers enrich the tradition of Southern literature as well as American eco-literature.

Clinical Effectiveness of the Plate Screw Internal Fixation Technique in the Treatment of Patients with Traumatic Fractures of Long Bones in the Lower Extremities

Objective: To investigate the effectiveness of the plate screw internal fixation technique on the clinical outcomes of patients with traumatic fractures of long bones in the lower extremities. Methods: From January 2022 to December 2023, 70 patients with traumatic fractures of long bones in the lower extremities were admitted to the hospital and randomly divided into two groups: the control group and the observation group, each consisting of 35 cases. The control group underwent traditional closed interlocking intramedullary nailing, while the observation group received internal fixation with steel plates and screws. Relevant surgical indicators, treatment effectiveness, and postoperative complication rates were compared between the two groups. Results: The observation group exhibited significantly short surgical duration (80.65 ± 5.01 vs. 88.36 ± 5.26 minutes), fracture healing time (13.27 ± 0.32 vs. 15.52 ± 0.48 weeks), and hospitalization days (10.49 ± 1.13 vs. 16.57 ± 1.15 days) compared to the control group (P = 0.000). The effective treatment rate was significantly higher in the observation group (29/82.86%) than in the control group (21/60.00%), with a significant difference observed (χ2 = 4.480, P = 0.034). Additionally, the complication rate in the observation group (2/5.71%) was significantly lower than that in the control group (8/22.86%), with a correlated difference (χ2 = 4.200, P = 0.040). Conclusion: The plate screw internal fixation technique demonstrates significant clinical efficacy in treating traumatic fractures of long bones in the lower extremities. It improves the healing rate, reduces complications, and represents a safe and effective treatment strategy worthy of widespread use and application.

Hypoxia-preconditioned bone marrow-derived mesenchymal stem cells protect neurons from cardiac arrest-induced pyroptosis

Cardiac arrest can lead to severe neurological impairment as a result of inflammation,mitochondrial dysfunction,and post-cardiopulmonary resuscitation neurological damage.Hypoxic preconditioning has been shown to improve migration and survival of bone marrow–derived mesenchymal stem cells and reduce pyroptosis after cardiac arrest,but the specific mechanisms by which hypoxia-preconditioned bone marrow–derived mesenchymal stem cells protect against brain injury after cardiac arrest are unknown.To this end,we established an in vitro co-culture model of bone marrow–derived mesenchymal stem cells and oxygen–glucose deprived primary neurons and found that hypoxic preconditioning enhanced the protective effect of bone marrow stromal stem cells against neuronal pyroptosis,possibly through inhibition of the MAPK and nuclear factor κB pathways.Subsequently,we transplanted hypoxia-preconditioned bone marrow–derived mesenchymal stem cells into the lateral ventricle after the return of spontaneous circulation in an 8-minute cardiac arrest rat model induced by asphyxia.The results showed that hypoxia-preconditioned bone marrow–derived mesenchymal stem cells significantly reduced cardiac arrest–induced neuronal pyroptosis,oxidative stress,and mitochondrial damage,whereas knockdown of the liver isoform of phosphofructokinase in bone marrow–derived mesenchymal stem cells inhibited these effects.To conclude,hypoxia-preconditioned bone marrow–derived mesenchymal stem cells offer a promising therapeutic approach for neuronal injury following cardiac arrest,and their beneficial effects are potentially associated with increased expression of the liver isoform of phosphofructokinase following hypoxic preconditioning.

AAV-mediated expression of p65shRNA and bone morphogenetic protein 4 synergistically enhances chondrocyte regeneration

BACKGROUND:Adeno-associated virus(AAV)gene therapy has been proven to be reliable and safe for the treatment of osteoarthritis in recent years.However,given the complexity of osteoarthritis pathogenesis,single gene manipulation for the treatment of osteoarthritis may not produce satisfactory results.Previous studies have shown that nuclear factorκB could promote the inflammatory pathway in osteoarthritic chondrocytes,and bone morphogenetic protein 4(BMP4)could promote cartilage regeneration.OBJECTIVE:To test whether combined application of AAV-p65shRNA and AAV-BMP4 will yield the synergistic effect on chondrocytes regeneration and osteoarthritis treatment.METHODS:Viral particles containing AAV-p65-shRNA and AAV-BMP4 were prepared.Their efficacy in inhibiting inflammation in chondrocytes and promoting chondrogenesis was assessed in vitro and in vivo by transfecting AAV-p65-shRNA or AAV-BMP4 into cells.The experiments were divided into five groups:PBS group;osteoarthritis group;AAV-BMP4 group;AAV-p65shRNA group;and BMP4-p65shRNA 1:1 group.Samples were collected at 4,12,and 24 weeks postoperatively.Tissue staining,including safranin O and Alcian blue,was applied after collecting articular tissue.Then,the optimal ratio between the two types of transfected viral particles was further investigated to improve the chondrogenic potential of mixed cells in vivo.RESULTS AND CONCLUSION:The combined application of AAV-p65shRNA and AAV-BMP4 together showed a synergistic effect on cartilage regeneration and osteoarthritis treatment.Mixed cells transfected with AAV-p65shRNA and AAV-BMP4 at a 1:1 ratio produced the most extracellular matrix synthesis(P<0.05).In vivo results also revealed that the combination of the two viruses had the highest regenerative potential for osteoarthritic cartilage(P<0.05).In the present study,we also discovered that the combined therapy had the maximum effect when the two viruses were administered in equal proportions.Decreasing either p65shRNA or BMP4 transfected cells resulted in less collagen II synthesis.This implies that inhibiting inflammation by p65shRNA and promoting regeneration by BMP4 are equally important for osteoarthritis treatment.These findings provide a new strategy for the treatment of early osteoarthritis by simultaneously inhibiting cartilage inflammation and promoting cartilage repair.

基于BONeS设计系统的多媒体互联网通讯仿真

ＢＯＮｅＳ是美国 Ｃａｄｅｎｃｅ公司 Ａｌｔａ Ｇｒｏｕｐ开发出的一套用于网络通讯仿真和计算机结构分析的系统设计自动化工具．介绍利用该工具进行多媒体互联网通讯仿真设计，并根据ＴＣＰ／ＩＰ的确认重发和滑动窗口流量控制机制，分析ＴＣＰ／ＩＰ协议的不同重发延迟和窗口设置方案对多媒通讯ＱｏＳ的影响．

The characterization of acid and pepsin soluble collagen from ovine bones (Ujumuqin sheep)

Ovine bones are the major by-products after slaughtered. The present study was conducted to extract and characterize acid soluble collagens （ASC） and pepsin soluble collagens （PSC） from ovine bones （Ujumuqin sheep）. Ovine bones collagen were identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis （SDS-PAGE） and liquid chromatography-tan- dem mass spectrometry （LC-MS/MS） as type I collagen. The results of Fourier transform infrared （FTIR） spectra analysis testified the existence of triple superhelical structure in both ASC and PSC, showing pepsin did not disrupt the triple helical structure of ovine bones collagen. Glycine, accounting for one-third of total amino acids, was the major amino acid for ovine bones collagen. Higher imino acid content was responsible for higher thermal denaturation temperature of ovine bones collagen compared to fish collagens. The isoelectric point of ASC was lower than PSC due to the higher content of acidic amino acids. Therefore, this study provides the potential reference for collagen extraction and application of ovine bones by-procduct.

Florid reactive periostitis ossificans of the humerus: Case report and differential diagnosis of periosteal lesions of long bones

A case of florid reactive periostitis ossificans(RPO) arising in a long bone is presented. This is a rare bone proliferation with a pronounced periosteal reaction. Less than 100 cases have been described in the literature with far fewer outside the bones of the hand, feet, fingers, and toes. Although the etiology is unknown, a relationship to preceding trauma is suggested. The imaging and histologic features show an overlap with other bone lesions including bizarre parosteal osteochondromatous proliferation, subungual exostosis, and malignant surface tumors of bone and cartilage which include, periosteal and parosteal osteosarcoma. It is important to recognize the clinical presentation and diagnostic features of RPO as a benign entity so that it is not mistaken for a more aggressive neoplasm. We present a case of a right distal humeral lesion that on histopathological review revealed florid RPO. This diagnosis was not suspected on imaging studies, but was made on open biopsy of the mass. The patient remains disease free, years postoperatively. In addition to presenting this unique case report, we review the pertinent literature, and offer a differential diagnosis and treatment strategy for its management.

The value of bone scintigraphy on the determination of the full extent of tumor involvement in jaw bones

Objective： To prospectively investigate the value of bone scintigraphy on determining the full extent of tumor involvement in jaw bones and to assess the presence of metastases. Methods： This study had local ethical committee approval, and all patients gave written informed consent. Thirty seven consecutive patients with primary malignant tumor in jaw bones were recruited for the study. Bone scintigraphy was performed in all patients before surgery to measure the full extent of bony involvement, which was compared with histologic findings. Results： Whole body scan revealed one case with multiple bony metastases. Resection specimens of 36 bone neoplasms were pathologically analyzed to identify type and size of each tumor. The lengths of the tumor involvement in jaw bones defined by bone scintigraphy and pathology were 5.62 ± 1.58 cm, 4.48 ± 1.57 cm, respectively （P 〈 0.05）. The tumor negative margins from removed specimens according to bone scintigraphy were pathologically confirmed. With histologic findings as the standard of reference, the accuracy of bone scintigraphy was 100% （36 of 36 patients） in determining the full extent of tumor involvement in jaw bones. Conclusion： Bone scintigraphy tends to offer specific guidelines in determining the appropriate extent of bone resection while entirely clearing the tumor cells and preserving functions whenever possible and in establishing the bony metastases.

Study of the Textural Properties of Bovine Bones Char under Different Conditions

Environmental pollution is today a very important issue and the development of low cost materials and different sources need to be investigated. Our research group for several years she has been the development of adsorbent materials for industrial wastewater treatment and rivers. In this research compares the porosity developed by two different treatments using bovine bones to adsorb metal ions. Using bovine bones as raw material, two carbonized samples were obtained under different conditions. One of the carbonized samples was obtained in an oxidizing atmosphere at up to 600℃ for 2 hours. The other was obtained in an inert atmosphere at up to 800℃, during 2 hours. Different textural characteristics were obtained in each of the carbonized samples according to the conditions of synthesis. The carbonized sample obtained in the oxidizing atmosphere, CHUOX, produces a great pore distribution, with a significant mesopore volume, reflected in the hysteresis loop, while in carbonized bone obtained in an inert atmosphere, CHUN, a formation of micropores and mesopores smaller than that obtained in the other carbonized sample is observed. The surface area obtained is 130 m2 g-1 for CHUOX and 170 m2 g-1 for CHUN. Furthermore, the adsorption capacity of Ni2+ and Cu2+ ions from solution was measured for these two carbonized samples, and a higher retention of both ions in the carbonized sample obtained in the inert atmosphere was found, with values between 28.57 and 67.56 mg g-1. The immersion enthalpies of carbonized samples in ion solutions are determined with an exothermic effect for the solution-solid interaction.

FEATURE EXTRACTION OF BONES AND SKIN BASED ON ULTRASONIC SCANNING

In the prosthetic socket design, aimed at the high cost and radiation deficiency caused by CT scanning which is a routine technique to obtain the cross-sectional image of the residual limb, a new ultrasonic scanning method is developed to acquire the bones and skin contours of the residual limb. Using a pig fore-leg as the scanning object, an overlapping algorithm is designed to reconstruct the 2D cross-sectional image, the contours of the bone and skin are extracted using edge detection algorithm and the 3D model of the pig fore-leg is reconstructed by using reverse engineering technology. The results of checking the accuracy of the image by scanning a cylinder work pieces show that the extracted contours of the cylinder are quite close to the standard circumference. So it is feasible to get the contours of bones and skin by ultrasonic scanning. The ultrasonic scanning system featuring no radiation and low cost is a kind of new means of cross section scanning for medical images.

The Effects of Lactobacillus rhamnosus GG on Mechanical Properties of Long Bones and Body Composition in Immunodeficient Mice

This study aimed to assess whether a daily supplementation with Lactobacillus rhamnosus GG (LGG) can alter the body composition as well as bone turnover and the mechanical properties of the bones in systemic immunodeficiency. For this, we use an in vivo model of severe combined immunodeficient (scid) mice supplemented daily with LGG over 8 weeks period. After 8 weeks of the treatment, the animals were assessed by DEXA and then the blood was collected from the hepatic portal vein for bone turnover biomarkers;post-mortem, the caecum was removed for isolation and enumeration of the gut bacteria, while femurs/tibiae were excised for the assessment of their mechanical properties. LGG treatment affected the composition of the gut microbiota at the order level, and it decreased (P = 0.002) total adipose tissue content. Moreover, LGG treatment decreased the stiffness (N/mm) of both femurs (P = 0.008) and tibiae (P = 0.011). To conclude, this study shows that dietary supplementation with LGG in immunodeficient animals can alter mechanical properties of the long bones and concomitantly it can modify host’s total adiposity level.

Bennett's fracture associated with fracture of Trapezium——A rare injury of first carpo-metacarpal joint

Association of fracture of trapezium with Bennett'sfracture is very rare and makes reduction and stabilisation more difficult. We are reporting a rare case of Bennett's fracture with fracture of the trapezium and subluxation of the carpo-metacarpal joint(CMC) joint. The patient was a 47-year-old school teacher who fell from his motorbike on his outstretched right dominant hand. Radiographs and computed tomography showed fracture of the trapezium with subluxation of the CMC joint, associated with Bennett's fracture. Open reduction and internal fixation was carried out. Trapezium was reduced first and secured with a 2 mm diameter screw. Bennett's fracture was then reduced and fixed with two per-cutaneously placed Kirchner's wires. CMC was stabilised with percutaneous Kirchner's wires. Latest follow up at 12 mo showed a healed fracture with good reduction of the CMC joint. Clinically patient had no pain and normal extension, abduction and opposition of the thumb. QuickD ASH score was 3.9/100. Thus, fracture of trapezium associated with a Bennett's fracture is a rare injury and if ignored it may lead to poor results. This injury is more challenging to manage than an isolated Bennett's fracture as anatomical reduction of the trapezium with reduction of the first CMC is needed. Fracture of the trapezium should be fixed first as this will provide a stable base for reduction of the Bennett's fracture.

Dorsal approach for isolated volar fracture-dislocation of the base of the second metacarpal:A case report

BACKGROUND We report a case with the displacement of an articular fracture fragment of the base of the second metacarpal from the ulnar to the volar side,treated via the dorsal approach.The dorsal approach can be a good option not only because it allows direct observation of ligament damage and fixation of bone fragments but also because the thin subcutaneous tissue makes the approach easier.CASE SUMMARY A 45-year-old man with a right hand injury visited the hospital.A small bone fragment was identified using plain radiography.Lateral radiography revealed the fragment as lying over the volar aspect of the carpometacarpal(CMC)joint.Computed tomography revealed that approximately one-third of the CMC joint surface of the second metacarpal was damaged.We provisionally diagnosed an intra-articular fracture with significant CMC joint instability and performed open reduction and internal fixation.We made a dorsal longitudinal incision over the CMC joint between the second and third metacarpals.The dorsal ligament of the third CMC joint was torn.We thought it had been dislocated to the volar side and spontaneously reduced to that position.There are only few reports of volar dislocation of CMC joint fractures,particularly of the second and third metacarpals;our report is unique as our patient had an intact interosseous ligament between the second and third metacarpals.CONCLUSION Although past reports have used a palmar approach,the dorsal approach is a good option for these cases.

Crosstalk between Wnt and bone morphogenetic protein signaling during osteogenic differentiati

Mesenchymal stem cells(MSCs)originate from many sources,including the bone marrow and adipose tissue,and differentiate into various cell types,such as osteoblasts and adipocytes.Recent studies on MSCs have revealed that many transcription factors and signaling pathways control osteogenic development.Osteogenesis is the process by which new bones are formed;it also aids in bone remodeling.Wnt/β-catenin and bone morphogenetic protein(BMP)signaling pathways are involved in many cellular processes and considered to be essential for life.Wnt/β-catenin and BMPs are important for bone formation in mammalian development and various regulatory activities in the body.Recent studies have indicated that these two signaling pathways contribute to osteogenic differen-tiation.Active Wnt signaling pathway promotes osteogenesis by activating the downstream targets of the BMP signaling pathway.Here,we briefly review the molecular processes underlying the crosstalk between these two pathways and explain their participation in osteogenic differentiation,emphasizing the canonical pathways.This review also discusses the crosstalk mechanisms of Wnt/BMP signaling with Notch-and extracellular-regulated kinases in osteogenic differentiation and bone development.

First-Person Retrospective Narrative in The Lovely Bones

The Lovely Bones written by Alice Sebold is about a 14-year-old girl Susie who,as a ghost,tells her story as well as her family's after her death.Tiffs paper focuses on the characteristics of the first-person retrospective narrative in The Lovely Bones.Firstly,this paper introduces the story,the double focalizations of the first--person retrospective narrative and the purpose of the paper.It then discusses the three functions of the first-person retrospective narrative:enhancing authenticity,intensifying intimacy and contributing to the love theme of the story.Besides,the thesis points out the limitation of the first-person retrospective narrative:monotonous.Therefore,a shift of the narrative perspective is put forwards as the solution to the problem.

Icariin accelerates bone regeneration by inducing osteogenesisangiogenesis coupling in rats with type 1 diabetes mellitus

BACKGROUND Icariin(ICA),a natural flavonoid compound monomer,has multiple pharmacological activities.However,its effect on bone defect in the context of type 1 diabetes mellitus(T1DM)has not yet been examined.AIM To explore the role and potential mechanism of ICA on bone defect in the context of T1DM.METHODS The effects of ICA on osteogenesis and angiogenesis were evaluated by alkaline phosphatase staining,alizarin red S staining,quantitative real-time polymerase chain reaction,Western blot,and immunofluorescence.Angiogenesis-related assays were conducted to investigate the relationship between osteogenesis and angiogenesis.A bone defect model was established in T1DM rats.The model rats were then treated with ICA or placebo and micron-scale computed tomography,histomorphometry,histology,and sequential fluorescent labeling were used to evaluate the effect of ICA on bone formation in the defect area.RESULTS ICA promoted bone marrow mesenchymal stem cell(BMSC)proliferation and osteogenic differentiation.The ICA treated-BMSCs showed higher expression levels of osteogenesis-related markers(alkaline phosphatase and osteocalcin)and angiogenesis-related markers(vascular endothelial growth factor A and platelet endothelial cell adhesion molecule 1)compared to the untreated group.ICA was also found to induce osteogenesis-angiogenesis coupling of BMSCs.In the bone defect model T1DM rats,ICA facilitated bone formation and CD31hiEMCNhi type H-positive capillary formation.Lastly,ICA effectively accelerated the rate of bone formation in the defect area.CONCLUSION ICA was able to accelerate bone regeneration in a T1DM rat model by inducing osteogenesis-angiogenesis coupling of BMSCs.

Study on Production of Rubber Sealing Strips with Steel Bones

Rubber sealing strips with steel bones are used in car manufacturing that produced in large quantities. Cutting processes, such as milling and punching, are needed when the strips are produced. Accuracy, smoothness and flatness of the machined surface have to be guaranteed in the cutting process; moreover, deformation of the steel bone and peeling-off of the rubber must be avoided. Therefore cutting action of rubber/steel strips differs from that of rubber or metal workpiece separately. In this paper, milling and punching of rubber/steel strips were studied with the aim to increase the part quality of a production line for sealing strips of cars. Suitable cutting tools and fixtures are both necessary for cutting of the strips. The teeth of the milling saw should be made knife-edged and the cutting edge of the punching tool be inclined. Fixtures should be used to sustain the workpiece and resist deformation. By using of suitable tools and fixtures, high quality of rubber/steel sealing strips is achieved in the production line.

Comminuted olecranon fracture fixation with pre-contoured plate:Comparison of composite and cadaver bones

AIM: To determine whether use of a precontoured olecranon plate provides adequate fixation to withstand supraphysiologic force in a comminuted olecranon fracture model.METHODS: Five samples of fourth generation composite bones and five samples of fresh frozen human cadaveric left ulnae were utilized for this study. The cadaveric specimens underwent dual-energy X-ray absorptiometry(DEXA) scanning to quantify the bone quality. The composite and cadaveric bones were prepared by creating a comminuted olecranon fracture and fixed with a pre-contoured olecranon plate with locking screws. Construct stiffness and failure load were measured by subjecting specimens to cantilever bending moments until failure. Fracture site motion was measured with differential variable resistance transducer spanning the fracture. Statistical analysis was performed with two-tailed Mann-Whitney-U test with Monte Carlo Exact test.RESULTS: There was a significant difference in fixation stiffness and strength between the composite bones and human cadaver bones. Failure modes differed in cadaveric and composite specimens. The load to failure for the composite bones(n = 5) and human cadaver bones(n = 5) specimens were 10.67 nm(range 9.40-11.91 nm) and 13.05 nm(range 12.59-15.38 nm) respectively. This difference was statistically significant(P ? 0.007, 97% power). Median stiffness for composite bones and human cadaver bones specimens were 5.69 nm/mm(range 4.69-6.80 nm/mm) and 7.55 nm/mm(range 6.31-7.72 nm/mm). There was a significant difference for stiffness(P ? 0.033, 79% power) between composite bones and cadaveric bones. No correlation was found between the DEXA results and stiffness. All cadaveric specimens withstood the physiologic load anticipated postoperatively. Catastrophic failure occurred in all composite specimens. All failures resulted from composite bone failure at the distal screw site and not hardware failure. There were no catastrophic fracture failures in the cadaveric specimens. Failure of 4/5 cadaveric specimens was defined when a fracture gap of 2 mm was observed, but 1/5 cadaveric specimens failed due to a failure of the triceps mechanism. All failures occurred at forces greater than that expected in postoperative period prior to healing.CONCLUSION: The pre-contoured olecranon plate provides adequate fixation to withstand physiologic force in a composite bone and cadaveric comminuted olecranon fracture model.