Failure Of Osteosynthesis Research Articles

Titanium Cable Cerclage Increases the Load to Failure in Plate Osteosynthesis for Distal Femoral Fractures.

Background and Objectives: The reduction of two-part oblique or spiral fractures of the distal femur using steel wire cerclage prior to plate osteosynthesis is a proven procedure. In addition to being useful in fracture reduction, wire cerclage was also shown to increase the stability of osteosynthesis. Nevertheless, metal corrosion and the allergenic potency of steel remain problematic disadvantages of this method. A biomechanical study was carried out to evaluate titanium cable cerclage as an alternative supplement for plate osteosynthesis of a distal femoral two-part fracture. Materials and Methods: An unstable AO/OTA 32-A2.3 fracture was created in eleven pairs of nonosteoporotic human cadaver femora. All the samples were treated with polyaxial angular stable plate osteosynthesis. One femur from each pair was randomly selected for an additional fracture fixation with multifilament titanium cable cerclage. Stepwise cyclic axial loading was applied in a load-to-failure mode using a servohydraulic testing machine. Results: All specimens (mean age: 80 years; range: 57-91 years) withstood a cycling force of at least 1800 N. With a mean load of 2982 N (95% CI: 2629-3335 N), the pressure forces resulting in osteosynthesis failure were significantly higher in specimens with an additional titanium cerclage (Group 1) than in samples that were solely treated with plate osteosynthesis (Group 2) at 2545 N (95% CI: 2257-2834 N) (p = 0.024). In both groups, cutting out the distal screws at the condyle region, resulting in shearing of the distal fragment proximal to the fracture line, was the most frequent cause of construct failure. Among the specimens assigned to Group 1, 36% exhibited a specific fracture pattern, namely, a fracture of the dorsal buttress above the cerclage. Analysis of axial stiffness (p = 0.286) and irreversible deformity of the specimens revealed no differences between the groups (p = 0.374). Conclusion: Titanium cable cerclage application, as a supplement to an angular stable plate, resulted in an increased load to failure. In terms of stability, the use of this adjunct for fracture fixation of supracondylar two-part oblique femoral fractures might, therefore, be an option, especially in patients who are sensitive to nickel.

Enhancing Osteoporosis Management: A Thorough Examination of Surgical Techniques and Their Effects on Patient Outcomes.

Managing osteoporotic fractures in older individuals is a difficult task in orthopedic surgery. It requires a careful approach that combines advanced diagnostic methods, customized surgical treatments, and comprehensive rehabilitation strategies. This article presents the results of an analysis carried out at the University Emergency Hospital, Bucharest. The analysis specifically examines the treatment of osteoporotic fractures using different osteosynthesis techniques. Although diagnostic tools like dual-energy X-ray absorptiometry (DXA) and Fracture Risk Assessment Tool (FRAX) have improved, a considerable number of fractures still happen in people who do not have obvious osteoporosis. This emphasizes the importance of using additional diagnostic measures such as high-resolution peripheral quantitative computed tomography (HR-pQCT) and quantitative computed tomography (QCT) to improve the accuracy of predictions. The study demonstrates the intricate nature of surgical decision-making and the significance of adjusting techniques to meet the specific needs of each patient. An instance of osteosynthesis failure resulting from the inappropriate choice of method highlighted the crucial significance of a thorough preoperative assessment. The discussion highlights the importance of early mobilization and rehabilitation in reducing the risks associated with prolonged immobilization and improving patient recovery. This paper strongly supports the use of evidence-based and patient-centered methods in the management of osteoporotic fractures. It emphasizes the importance of utilizing the most recent advancements in diagnostic and surgical technologies. Promising advancements in orthopedic medicine lie in the future, particularly in the integration of interdisciplinary research and personalized medicine. These advancements have the potential to enhance patient outcomes in this population that is at high risk.

Treating pathological metastatic fractures of the humerus by compound osteosynthesis: a retrospective cohort study

BackgroundThe number of malignant tumors is increasing as are bone metastases, such as those in the humerus. Arm function is important for an independent everyday life. In this study, compound osteosynthesis of metastatic fractures of the humerus is examined for its suitability in light of the competing risk of death. Materials and MethodsThis retrospective monocentric study includes a cohort of tumor patients who underwent primary compound osteosynthesis for pathological humeral fractures. The main endpoint was the continued existence of compound osteosynthesis using competing risk analysis (CRA) to contrast failure and death. Failure was defined as mechanical failure of the osteosynthesis construct like re-fracture or plate-and-screw dislocation or loosening, which provides an indication for re-intervention. Other complications are also described. ResultsWe included 36 consecutive patients (64% male, mean age 71.6 yrs.) from September 2007 to October 2020. In 58% of the cases, the left humerus was fractured. Lung carcinoma was the most common cause of bone metastases (27.8%). Compound osteosynthesis was performed with a median delay of five days after diagnosis of the pathologic fracture. Postoperative complications occurred in seven of the 36 patients (19.4%): radial nerve palsy (n = 3), postoperative hematoma (n = 2), re-fracture (n = 2) and screw loosening (n = 1). Few mechanical failures (8.3%) occurred within the first year; only one patient needed revision of the osteosynthesis (2.8%). Median patient survival after compound osteosynthesis was 26.6 weeks. CRA showed that for up to two years, the risk of death is clearly dominant over the risk of osteosynthesis failure from surgery. ConclusionOur study shows that compound osteosynthesis of the humerus is a suitable option for patients with pathologic humerus fractures. Compound osteosynthesis of the humerus usually survives the duration of malignant tumor disease.

Outcome Analysis of Fixed angle Locking Plate in Comminuted Patella Fractures : A Single Centre Prospective study from South India with Early Results.

Comminuted patella fractures pose a challenge to orthopaedic surgeons , since tension band wiring and cerclage is not effective and often lead to loosening of wires, hardware problem, dislocation of fracture and failure of osteosynthesis resulting in post-traumatic osteoarthritis and knee stiffness. The aim of this study is to evaluate the clinical outcome in patients with AO 34C2 and 34C3 highly comminuted patella fractures treated with unidirectional fixed angle titanium patella locking plate. Twelve patients who presented with AO 34C2 and 34C3 comminuted patella fractures, aged between 18-79 years were included in the study. All fractures were reduced and fixed with unidirectional angle fixed stable titanium patella locking plate. Knee range of motion and knee outcome survey activities of daily living scale (KOS-ADL) was used to evaluate the outcome. Union of fracture was achieved in all twelve patients. Mean flexion at final follow-up was 123° (110°-130°). None of the patients had extensor lag. One patient had hardware irritation which resolved at final followup. This technique serves as an effective option in highly comminuted patella fractures by providing excellent mechanical stability resulting in anatomical reduction , excellent functional outcome , lower incidence of hardware irritation or failure of osteosynthesis.

Reverse total shoulder arthroplasty for proximal humerus fractures: Primary or delayed after failed treatment?

BackgroundReverse total shoulder arthroplasty (RTSA) has recently become an option for the treatment of proximal humerus fractures (PHFs) or as a salvage procedure after failure of another treatment. The purpose of this study was to compare primary RTSA with delayed RTSA in the treatment of displaced PHFs. Study design & MethodsA retrospective cohort study was conducted on patients with PHFs who were treated between May 2013 and December 2021 with primary or delayed RTSA after failure of conservative treatment or osteosynthesis. Clinical data were withdrawn from our local computerized database. Complications, active range of motion, as well as the functional outcome were recorded at the end of the follow-up period. Differences between clinical outcomes were analyzed using a logistic regression analysis. ResultsA total of 70 individuals were included in this study (41 primary RTSA and 29 delayed RTSA). The mean of follow-up time was of 112 and 60 months, respectively. There were no differences between groups regarding fracture type according Neer Classification, ASA score or the presence of complications. Q-DASH and Oxford Shoulder scores were significantly better when patients underwent a primary RTSA (49.8 vs 31.4, p = 0.006 and 37.2 vs 27.5, p = 0.004 respectively). In addition, primary RTSA achieved more degrees of flexion and abduction than delayed RTSA (96.8 vs 72.9, p < 0.001 and 94.1 vs 69.3, p < 0.001 respectively). ConclusionPrimary RTSA for PHFs achieved better functional outcomes and a wider range of motion when compared with delayed RTSA. However, primary and delayed RTSA have similar complication and reintervention rates. Level of Clinical Evidence3

On the importance of accurate elasto-plastic material properties in simulating plate osteosynthesis failure.

Background: Plate osteosynthesis is a widely used technique for bone fracture fixation; however, complications such as plate bending remain a significant clinical concern. A better understanding of the failure mechanisms behind plate osteosynthesis is crucial for improving treatment outcomes. This study aimed to develop finite element (FE) models to predict plate bending failure and validate these against in vitro experiments using literature-based and experimentally determined implant material properties. Methods: Plate fixations of seven cadaveric tibia shaft fractures were tested to failure in a biomechanical setup with various implant configurations. FE models of the bone-implant constructs were developed from computed tomography (CT) scans. Elasto-plastic implant material properties were assigned using either literature data or the experimentally derived data. The predictive capability of these two FE modelling approaches was assessed based on the experimental ground truth. Results: The FE simulations provided quantitatively correct prediction of the in vitro cadaveric experiments in terms of construct stiffness [concordance correlation coefficient (CCC) = 0.97, standard error of estimate (SEE) = 23.66, relative standard error (RSE) = 10.3%], yield load (CCC = 0.97, SEE = 41.21N, RSE = 7.7%), and maximum force (CCC = 0.96, SEE = 35.04, RSE = 9.3%), when including the experimentally determined material properties. Literature-based properties led to inferior accuracies for both stiffness (CCC = 0.92, SEE = 27.62, RSE = 19.6%), yield load (CCC = 0.83, SEE = 46.53N, RSE = 21.4%), and maximum force (CCC = 0.86, SEE = 57.71, RSE = 14.4%). Conclusion: The validated FE model allows for accurate prediction of plate osteosynthesis construct behaviour beyond the elastic regime but only when using experimentally determined implant material properties. Literature-based material properties led to inferior predictability. These validated models have the potential to be utilized for assessing the loads leading to plastic deformation in vivo, as well as aiding in preoperative planning and postoperative rehabilitation protocols.

Treatment of intertrochanteric fractures using cephalomedullary nail: One or two cephalic screws?

ObjectivesTo determine the incidence of cut-out, cut-in, cut-through, Z-effect, and reverse Z-effect in two cephalomedullary nail (CMN) systems: one with single cephalic screw fixation and the other with dual-screw fixation using a lag screw and an anti-rotation screw. MethodsA retrospective study from a cohort of patients was conducted between January 2017 and August 2019 in patients with intertrochanteric fractures treated with osteosynthesis using CMN. ResultsOne hundred ninety-six patients with intertrochanteric fractures who met the inclusion criteria were recruited. The median age was 81 years [interquartile range (IQR) 12]. Seventy-six percent had fractures classified as Orthopaedic Trauma Association/Arbeitsgemeinschaft für Osteosynthesefragen (OTA/AO) 31A2. Twenty-one mechanical complications occurred, 8.7% (17) was cut-out with a single cephalic screw CMN and 2% (4) was Z-effect with a dual-screw CMN non-integrated. The median tip-apex distance (TAD) was 19.4 mm (IQR 10.8) in patients who experienced cut-out and 19 mm (IQR 10) in those who experienced Z-effect. The median time to cut-out occurrence was 39,5 days (IQR 47,5), while the median time to Z-effect was 90 days (IQR 86). ConclusionsThe incidence of osteosynthesis failure using CMN is more frequent in patients treated with a single cephalic screw CMN. Level of EvidenceTherapeutic, Level III

Etiologies of Orthopedic Implant Removal Among Patients Who Underwent Orthopedic Fixation Surgeries in King Abdulaziz Medical City.

Hardware removal surgeries are considerably common. However, the justifications for these surgeries are debatable. The indications may vary from pain, surgical site infection, or failure of osteosynthesis. Additionally, the surgery can be performed withoutmedical indication. Following these surgeries, many complications can occur. Therefore, surgeons and patients should be aware of the appropriate indications and have realistic expectations of the risks and benefits of implant removal. This was a retrospective chart review study. We included all patients aged 17-86 years who underwent hardware removal surgery in the orthopedic surgery department of King Abdulaziz Medical City, Riyadh, Saudi Arabia, from 2010 to 2019. All relevant data, such as demographic characteristics, location and type of hardware, indication for hardware removal, duration between insertion and removal, and complications after removal were recorded and analyzed. A total of 244 medical records were reviewed with a mean patient age of 34years. Out of the total, 190 patients (77.9%) were male. The femur was the most common location of hardware removal, in 50 cases (20.58%). Plates and screws were the most common type of implants (40.2%). Most patients underwent hardware implantation because of fractures (89.3%). In total, 119 patients (48.8%) had the hardware removed electively. Only 29 patients (12%) reported postoperative complications; 190 patients (77.9%) were advised by their surgeon against hardware removal. Hardware removal procedures are commonly performed worldwide for various reasons, including infection, pain, and loosening. In this study, we have outlined the reasons for implant removal, the locations, complications, and the rationale behind this surgery. We have provided a new decision-making assessment, aimed at the general population and surgeons alike, that will help patients better comprehend the complications and risks associated with this elective surgery.

Trochanteric fractures: Tip-Apex distance, Calcar Tip-Apex distance, and Chang criteria-a multiple variable analysis.

Failure of osteosynthesis is a common complication of the nailing of trochanteric fractures which typically occurs through form of cut-out. Tip-Apex distance (TAD), Calcar Tip-Apex distance (CalTAD), and Chang criteria are validated variables to predict failure of cephalomedullary nailing. This is a retrospective study which analyzes treatment of trochanteric fractures from 2018 to 2020 (n = 296) evaluating postoperative radiographs and factors of mechanical failure. Our objective was to assess correlation among these variables and their influence on mechanical failure, either individually or creating a new score. Our results support the CalTAD and Chang's criteria as valid predictors of mechanical failure. Furthermore, they empathize the importance of fracture reduction and proper placement of cervical screw. To our knowledge, this is the first study performing multivariate analysis including these 3 variables.

Hip Fracture Due to Osteomalacia Secondary to Celiac Disease

Background: Hip fracture is uncommon among younger patients but can have devastating consequences. Therefore, hip fracture caused by minimal trauma requires examinations on calcium metabolism to identify the primary cause. Methods: We present a clinical case of an 18-year-old male patient who suffered a subcapital fracture of the left hip due to minimal trauma while playing soccer. The patient immediately underwent surgery, which is closed reduction and internal fixation with two cancellous screws installed. Subsequently, metabolic tests showed severe vitamin D deficiency (27.1 nmol/L - normal above 75 nmol/L) and high levels of IgA anti-transglutaminase antibodies (2502.40 U/mL). Digestive biopsy confirmed the diagnosis of celiac disease, and he was treated with a gluten-free diet and calcium and vitamin D supplements. Results: After two years of follow-up, the patient is pain-free, with full hip mobility. There were no complications (osteosynthesis failure, avascular necrosis or pseudarthrosis) and serum levels of vitamin D, and IgA anti-transglutaminase antibodies had normalized. Conclusion: In young patients presenting with low energy trauma fractures, vitamin D deficiency should be considered as a possible etiology, and the reason for such osteomalacia, such as celiac disease, should be identified.

Comparative study of patients with midshaft clavicle fracture fixed with a locked plate via an open versus percutaneous approach

ObjectiveTo compare the results of surgical treatment of midshaft clavicle fractures, treated with the technique of minimally invasive plate osteosynthesis (MIPO) with locking compression plate versus open reduction and internal fixation (ORIF) with locked plate. MethodsQuasi-randomized comparative study, evaluating displaced midshaft clavicle fractures treated with MIPO versus ORIF, with procedures performed by a single surgeon. We evaluated patients at 12 months using the University of California at Los Angeles (UCLA) scale and radiographically at 8, 12, 26 and 52 weeks, in addition to describing complications. ResultsWe evaluated 44 patients; 22 submitted to MIPO and 22 to ORIF. The median UCLA scores at 12 months were 35 in the ORIF group and 35 in the MIPO group (p = 0.712). All patients had fracture healing at 3 months (p > 0.999). The mean surgery time was 87.5 min in the ORIF group and 47.5 in the MIPO (p < 0.001) group. As complications, 1 suture dehiscence (4.5%), 2 protruding plates (9.1%) and 1 change in sensitivity around the surgical wound (4.5%) were observed in the MIPO group, while in the ORIF group, 15 changes in sensitivity (68.2%) and 3 hypertrophic scars (13.6%) were observed. The only complication that showed a difference between the groups was the change in sensitivity (p < 0.001). No cases of pseudarthrosis or failure of osteosynthesis were identified in either technique. ConclusionThis study demonstrated that the two treatments, ORIF and MIPO, are equally effective in the treatment of displaced middle third clavicle fractures. However, MIPO is superior to ORIF in regard to reduced surgical time and preservation of supraclavicular nerve sensitivity.

Analysis of Three-Dimensional Bone Microarchitecture of the Axis Exposes Pronounced Regional Heterogeneity Associated with Clinical Fracture Patterns

The odontoid process (dens) of the second cervical vertebra (axis) is prone to fracture. While the importance of its skeletal integrity has been previously noted, representative three-dimensional microarchitecture analyses in humans are not available. This study aimed to determine the bone microarchitecture of the axis using high-resolution quantitative computed tomography (HR-pQCT) and to derive clinical implications for the occurrence and treatment of axis fractures. For initial clinical reference, the apparent density of the axis was determined based on clinical computed tomography (CT) images in patients without and with fractures of the axis. Subsequently, 28 human axes (female 50%) obtained at autopsy were analyzed by HR-pQCT. Analyses were performed in three different regions corresponding to zones I (tip of dens), II (base of dens), and III (corpus axis) of the Anderson and D’Alonzo classification. Lower apparent densities based on clinical CT data were detected in zone II and III compared to zone I in both the group without and with fracture. In the autopsy specimens, cortical thickness and bone volume fraction decreased continuously from zone I to zone III. Trabecular and cortical tissue mineral density was lowest in zone III, with no differences between zones I and II. In conclusion, our clinical and high-resolution ex vivo imaging data highlight a marked regional heterogeneity of bone microarchitecture, with poor cortical and trabecular properties near the dens base. These results may partly explain why zones II and III are at high risk of fracture and osteosynthesis failure.

Plate osteosynthesis combined with bone cement provides the highest stability for tibial head depression fractures under high loading conditions

Older patients sustaining tibial head depression fractures often cannot follow the post-operative rehabilitation protocols with partial weight-bearing of the affected limb, leading to osteosynthesis failure, cartilage step-off and arthritis development. Therefore, the aim of this study was to analyse the biomechanical performance of different types of osteosyntheses alone and in combination with bone cement simulating cyclically high loading conditions of tibial head depression fractures. Lateral tibial head depression fractures (AO: 41-B2.2; Schatzker type III) were created in synthetic bones and stabilized using three different osteosyntheses alone and in combination with a commonly used bone cement (chronOS™): 2 screws, 4 screws in the jail technique and a lateral angle-stable buttress plate. After fixation, the lateral tibial plateau was axially loaded in two, from each other independent testing series: In the first test protocol, 5000 cycles with 500 N and in the end load-to-failure tests were performed. In the second test protocol, the cyclic loading was increased to 1000 N. Parameters of interest were the displacement of the articular fracture fragment, the stiffness and the maximum load. The osteosyntheses revealed a higher stiffness in combination with bone cement compared to the same type of osteosynthesis alone (e.g., 500 N level: 2 screws 383 ± 43 N/mm vs. 2 screws + chronOs 520 ± 108 N/mm, increase by 36%, p < 0.01; 4 screws 368 ± 97 N/mm vs. 4 screws + chronOS 516 ± 109 N/mm, increase by 40%, p < 0.01; plate: 509 ± 73 N/mm vs. plate + chronOs 792 ± 150 N/mm, increase by 56%, p < 0.01). Bone cement reduced the displacement of the plate significantly (500 N level: plate: 8.9 ± 2.8 mm vs. plate + chronOs: 3.1 ± 1.4 mm, reduction by 65%, p < 0.01; 1000 N level: 16.9 ± 3.6 mm vs 5.6 ± 1.3 mm, reduction by 67%, p < 0.01). Thus, the highest stiffness and lowest displacement values were found when using the plate with bone cement in both loading conditions (500 N level: 2 screws + chronOs 3.7 ± 1.3 mm, 4 screws + chronOs 6.2 ± 2.4 mm; 1000 N level: 2 screws + chronOs 6.5 ± 1.2 mm, 4 screws + chronOs 5.7 ± 0.8 mm). From a biomechanical perspective, plate osteosynthesis of tibial head depression fractures should always be combined with bone cement, provides higher stability than 2-screw and 4-screw fixation and is a valid treatment option in cases where extraordinary stability is required.

Biomechanical Comparison of Cannulated Screw Osteosynthesis With Tension-Band Wiring for Proximal Fractures of the Fifth Metatarsal (Jones Fracture)

Jones fractures, which lie at the junction of the diaphysis to the metaphysis of the fifth metatarsal, are a well-described clinical issue. There are various surgical approaches, including the commonly performed cannulated screw osteosyntheses, and the less frequently used tension-band approach. The aim is to compare the biomechanical stability of these osteosyntheses. We performed an osteotomy on 16 fresh frozen fifth metatarsal bones from body donors representing a Jones fracture. The fractures were treated pairwise with screw osteosynthesis or tension-band wiring. This was followed by cyclic axial bending until osteosynthesis failure. Stability under axial bending force was higher in the screw osteosynthesis (mean: 70.0 ± 66.5 N) compared to the tension-band wiring (mean: 35.7 ± 23.3 N) group although not reaching statistical significance (p = .116). The study shows no statistically significant difference in biomechanical stability under axial loading between screw osteosynthesis and tension band wiring. Based on the data obtained, no differences can be observed from a biomechanical point of view. The study supports the established method of treating Jones fractures primarily with screw osteosynthesis. In addition, the data suggest that tension band wiring may be a good alternative osteosynthesis, for example, after failed casting treatment or failure of primary osteosynthesis.

Fracture analysis, indication for endoprosthesis and implant selection in proximal humeral fractures

Proximal humeral fractures (PHF) are the third most common fracture in humans and the incidence is increasing. There are basically three treatment strategies: conservative, joint-preserving reconstructive or joint-replacing procedures. In addition to fracture morphology, patient-specific and surgeon-specific factors are particularly important when deciding on treatment. The experience and training of the surgeon also play adecisive role. In the case of joint-preserving treatment, the risk of osteosynthesis failure and of sequelae of the fracture must always be assessed. If conservative or reconstructive treatment methods are not promising, the joint-replacing procedure is the treatment of choice. The anatomical fracture prosthesis is only indicated, if at all, for young patients with adestroyed humeral head with apreserved rotator cuff and large fragments of the tuberosities. In advanced age, the implantation of areverse endoprosthesis is increasingly used for dislocated, multifragmentary PHF. In both procedures, the anatomical healing of the tuberosities has asignificant impact on the functional outcome.

Revision Surgery Using Retrograde Nail versus Replating in Nonunion Distal Femur Fracture Treated with Plate.

Articular distal femur fractures represent 4% to 6% of femur fractures. Locking compression plates (LCPs) are the main treatment option. Nevertheless, a reoperation rate of 12.9% has been reported; nonunion is reported at 4.8%, delayed union at 1.6%, and malunion at 0.6%. Treatment of nonunions can be challenging as no unanimous consensus regarding the best surgical technique has been reached. The aim of this study was to evaluate and compare two types of revision surgery as treatment of LCP-treated articular distal femoral fracture nonunion: retrograde nail or replating. A retrospective cohort study of patients admitted from January 2015 to February 2017 for nonunion of AO/OTA 33C2 fractures previously treated with a lateral LCP was conducted. Patients were treated either with intramedullary nailing (Group A) or with replating (Group B). One independent observer performed clinically and radiographically followed up at 1, 3, 6, 9, 12, 24, and 36 months after surgery. The nonunion scoring system (NUSS) was used. Nine patients were included in our study. The mean follow-up was 2 years. Five patients were treated with intramedullary nailing and four with replating. The NUSS score was 24.2 ± 6.8 in the nailing group and 37.3 ± 3 in the replating group (P=0.03). In the nailing group, radiographic consolidation was obtained in all cases. In the replating group, nonunion was found in 3 patients and failure of osteosynthesis in one patient. Therefore, four patients (Group B) underwent implant removal and retrograde femoral nailing, obtaining radiological healing. The union time was 7.6 months in the nailing group. Retrograde intramedullary nailing can be used as an effective treatment of aseptic AO-33C distal femoral nonunion following primary locking plating.

Comparative evaluation of methods for osteosynthesis of diaphyseal radial fractures by the method of mathematical modeling

RELEVANCE. The surgical treatment of patients with diaphyseal forearm fractures has a variety of methods and requires a precision technique. The need for postoperative immobilization after osteosynthesis of diaphyseal fractures remains a controversial issue, since osteosynthesis failure and the formation of a pseudoarthrosis are sometimes observed.In addition, very little information about the role of the interosseous membrane in the rotational function of the forearm during osteosynthesis is available in the literature.The OBJECTIVE was to determine the forces occurring during rotational movements of the forearm that lead to the above complications.METHODS AND MATERIALS. The clinical part included the results of surgical treatment of 330 patients with diaphyseal fractures of the forearm; it consisted of the main group (170 - interlocking osteosynthesis) and the comparison group (138 - plate osteosynthesis). The third group consisted of 22 patients with complications of surgical treatment of diaphyseal fractures of the forearm. We performed a comparative assessment of plate and interlocking osteosynthesis of radial bone fractures by mathematical modelling to determine the forces occurring during forearm rotation that lead to nonunion, instability and plate fractures.RESULTS. In the main group, healing was achieved in all (170 patients), in the comparison group, healing was achieved in 128 (92.8 %), consolidation was achieved in all 22 patients with fracture complications who underwent reconstruction. A comparative assessment revealed that during plate osteosynthesis, zones of high stress concentration were located around the plate opening above the area of fracture and the nearest to it holes from both sides. In interlocking osteosynthesis of the radius, the stresses are evenly distributed around the nail. Pronation-supination movements with an amplitude of (±90)°, according to the experimental results, should lead to the destruction of the cortical plate fairly soon after implantation, while the nail made of ultra-fine Ti-6Al-7Nb alloy will maintain its integrity.CONCLUSION. Based on these findings, external immobilization is advisable to avoid complications such as osteosynthesis instability or plate fracture.

Patient safety in distal femoral resection knee arthroplasty for non-tumor indications: a single-center consecutive cohort study of 45 patients

BackgroundDistal femoral resection knee arthroplasty may be a viable option for several indications other than bone tumors. Resection knee arthroplasty appears to be becoming more common, but patients requiring this type of surgery are often elderly and with high comorbidity. The aim of this study was to report in-hospital complications, readmissions, reoperations, and mortality after distal femoral resection knee arthroplasty for non-tumor indications.MethodsWe retrospectively identified a consecutive cohort of 45 knees (45 patients) treated with distal femoral resection knee arthroplasty in a single institution between 2012 and 2021. Indications for surgery were failure of osteosynthesis (8), primary fracture treatment (2), periprosthetic fracture (22), and revision arthroplasty with severe bone loss (13). A major reoperation was defined as a major component exchange procedure or amputation. Mean follow-up was 3.9 years.ResultsThe mean age was 71.3 years (SD 12.3), and 64.4% were female; 8.9% were ASA I, 40% ASA II, and 51% ASA III. Median length of stay was 7 days (range 3–19) with no major in-hospital complications, but 55.6% (n = 25) required blood transfusion. The 90-day readmission rate was 17.8% (n = 8), of which 50% was prosthesis-related. Four patients (8.9%) underwent major reoperation due to infection (n = 2), mechanical failure (n = 1), or periprosthetic fracture (n = 1). The mortality rate was 0% ≤ 90 days and 2.2% ≤1 year.ConclusionsDistal femoral resection knee arthroplasty in this fragile patient population appears to be a viable and safe option considering that it is a limp salvage procedure most cases.

USO DAS UNIDADES HOUNSFIELD NO PLANEJAMENTO DA CIRURGIA ESPINHAL: REVISÃO SISTEMÁTICA E META-ANÁLISE

ABSTRACT Bone mineral density is a crucial factor in the success or failure of osteosynthesis in spine surgery; it shows the onset of osteoporosis and related complications. Its evaluation is verified by dual-energy X-ray absorptiometry (DEXA) and Hounsfield Unit (HU) measurement by CT scan. Objective: Determine the use of HU in surgical planning; compare utility in diagnosing osteoporosis by DEXA; and evaluate sensitivity in predicting complications. Method: A systemic literature review was conducted on PubMed, in line with PRISMA methodology. Including those who justified the use of pre-surgical planning, compared HU/DEXA, and assessed complications. For the statistical analysis, the χ2 was used. Results: 57 articles were identified by selecting nine that met the inclusion criteria. In patients undergoing spinal surgery for fixation and fusion for degenerative pathology, HU measurement showed a prevalence of osteoporosis of 58.5% (sensitivity 93.26%; specificity 90.22%), osteoporosis-associated complications of 24.5%, proper diagnosis of 71.98%, and screw release rate of 82.31%. Conclusions: UH measurement for the diagnosis of osteoporosis turns out to be more sensitive, specific, and predictive compared to DEXA, especially in elderly patients; it represents a useful tool in planning spinal surgery, minimizing the risk of complications such as screw release, fractures, pseudoarthrosis, subsidence of intersomatic devices, and kyphosis of the proximal junction. Level of evidence II; Study Design: Systematic Review and meta-analysis.

Patient-related factors predicting the failure of mandibular osteosynthesis

<b>Introduction</b>: Patients that do not comply with post- operative instructions are at higher risk of failure following mandibular fixation. However, anticipating those patients who will not comply is challenging and may lead to the incorrect choice of mandibular fixation type. Our aim was to identify those patient-related factors, that if known pre- operatively, may either potentially be modified or can be used to assist in the determination of which method of osteosynthesis is employed. <b>Methods</b>: All adult patients who underwent plate fixation of their mandible fractures in the symphysis to angle regions between 01 October 2018 and 01 June 2021 were retrospectively identified. The odds of developing post- operative complications and requiring a return to theatre were determined for different patient-related factors and methods of plate fixation. <b>Results</b>: Of 337 fractures treated using load sharing principles, 27/337 (8.01%) developed complications and 20/337 (5.93%) required a return to theatre (RTT) for repeat osteosynthesis. Of 74 fractures treated using load-bearing principles, 7/74 (9.46%) developed complications and 2/74 (2.70%) required a return to theatre for repeat osteosynthesis. In patients with known substance misuse, the odds of the patient needing to return to theatre was significantly higher for those that underwent load sharing osteosynthesis than load bearing osteosynthesis (p = 0.048, OR=0.152, CI: 0.024–0.953). <b>Conclusions</b>: This analysis found that of those patient-related factors, known substance misuse has a higher risk of return to theatre and would suggest that fractures in such patients should be primarily treated by load-bearing fixation.