Experimental study on the biomechanical stability of complex acetabular fractures in the quadrilateral area: application of a dynamic anterior titanium-plate screw system.

BACKGROUND AND OBJECTIVE: Complex acetabular fractures involving quadrilateral areas are more challenging to treat during surgery. To date, there has been no ideal internal fixation for these acetabular fractures. The purpose of this study was to evaluate the biomechanical stability of complex acetabular fractures using a dynamic anterior titanium-plate screw system of the quadrilateral area (DAPSQ) by simulating the standing and sitting positions of pelvic specimens. MATERIALS AND METHODS: Eight formal in-preserved cadaveric pelvises aged 30-50 years were selected as the research objects. First, one hip of the normal pelvises was randomly used as the control model (group B) for measurement, and then one hip of the pelvises was randomly selected to make the fracture model in the 8 intact pelvises as the experimental model (group A) for measurement. In group A, acetabular both-column fractures in the quadrilateral area were established, and the fractures were fixed by DAPSQ. The biomechanical testing machine was used to load (simulated physiological load) from 400 N to 700 N at a 1 mm/min speed for 30 s in the vertical direction when the specimens were measured at random in simulated standing or sitting positions in groups. The horizontal displacement and longitudinal displacement of the acetabular fractures in the quadrilateral area were measured in both the standing and sitting simulations. RESULTS: As the load increased, no dislocation or internal fixation breakage occurred during the measurements. In the standing position, the horizontal displacement of the quadrilateral area fractures in group A and group B appeared to be less than 1 mm with loads ranging from 400 N to 700 N, and there was no significant difference between group A and group B (p > 0.05). The longitudinal displacement appeared to be greater than 1 mm with a load of 700 mm in group A (700 N, 2 cases), and the difference was significant between group A and group B (p < 0.05). In the sitting position, the horizontal and longitudinal displacements of the quadrilateral areas were within 0.5 mm in group A and group B, and there was no significant difference between group A and group B (p > 0.05). CONCLUSION: For complex acetabular fractures in the quadrilateral area, DAPSQ fixation may provide early sitting stability, but it is inappropriate for patients to stand too early.

Operative treatment of isolated epiphyseal fracture of the distal fibula: 1 case report and literature review.

Pediatric ankle injuries are common; ankle epiphyseal fractures are also common in children. But isolated distal epiphyseal fibular fractures of the distal fibula are clinically rare. We describe one unusual case of an adolescent with a completely displaced Salter-Harris type II distal fibular epiphyseal fracture. The attempt of closed reduction failed, and the patient required open reduction and internal fixation. The localized periosteum and the superior peroneal retinaculum were avulsed from the distal fibular metaphysis, with the peroneal tendons underneath exposed but no obvious subluxation. To the best of our knowledge, this combination of injuries has not been previously reported.

Distal Clavicle Fracture Repair Utilizing Plate and Suture-Button Fixation: Optimizing Intraoperative Fluoroscopy.

VIDEO AVAILABLE AT: https://ota.org/education/ota-online-resources/video-library-procedures-techniques/distal-clavicle-fracture-repair.

Increasing the Threshold to Perform Preperitoneal Pelvic Packing Decreases Morbidity Without Affecting Mortality.

OBJECTIVES: To determine the effectiveness of an updated protocol that increased the transfusion threshold to perform preperitoneal pelvic packing in patients with pelvic ring injuries and hemodynamic instability (HDI). DESIGN: Retrospective review. SETTING: Urban level 1 trauma center. PATIENTS SELECTION CRITERIA: Severely injured (injury severity score > 15) patients with pelvic ring injuries treated before and after increasing the threshold to perform preperitoneal pelvic packing from 2 to 4 units of red blood cells (RBCs). HDI was defined as a systolic blood pressure <90 mm Hg. OUTCOME MEASURES AND COMPARISONS: Mortality from hemorrhage, anterior pelvic space infections, and venous thromboembolisms before and after increasing preperitoneal pelvic packing threshold. RESULTS: One hundred sixty-six patients were included: 93 treated under the historical protocol and 73 treated under the updated protocol. HDI was present in 46.2% (n = 43) of the historical protocol group and 49.3% (n = 36) of the updated protocol group (P = 0.69). The median age of patients with HDI was 35.0 years (interquartile range 26.0-52.0), 74.7% (n = 59) were men, and the median injury severity score was 41.0 (interquartile range 29.0-50.0). Patients with HDI in the updated protocol group had a lower heart rate on presentation (105.0 vs. 120.0; P = 0.004), required less units of RBCs over the first 24 hours (6.0 vs. 8.0, P = 0.03), and did not differ in age, injury severity score, systolic blood pressure on arrival, base deficit or lactate on arrival, resuscitative endovascular balloon occlusion of the aorta, resuscitative thoracotomy, angioembolization, or anterior pelvis open reduction internal fixation (P > 0.05). The number of PPPs performed decreased under the new protocol (8.3% vs. 65.1%, P < 0.0001), and there were fewer anterior pelvic infections (0.0% vs. 13.9%, P = 0.02), fewer VTEs (8.3% vs. 30.2%; P = 0.02), and no difference in deaths from acute hemorrhagic shock (5.6% vs. 7.0%, P = 1.00). CONCLUSIONS: Increasing the transfusion threshold from 2 to 4 units of red blood cells to perform pelvic packing in severely injured patients with pelvic ring injuries decreased anterior pelvic space infections and venous thromboembolisms without affecting deaths from acute hemorrhage. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Primary Closure of External Fixator Pin Sites Is Safe After Orthopaedic Trauma Surgery.

OBJECTIVES: To determine if rates of pin site infection and surgical site infection among patients managed with primary closure after external fixator removal were similar to those allowed to heal secondarily. DESIGN: Retrospective cohort. SETTING: Urban/Suburban Academic Level I Trauma Center. PATIENT SELECTION CRITERIA: Patients who had received a lower extremity external fixator for provisional management before definitive fixation of lower extremity fractures were included with pin site wounds closed primarily or allowed to heal by secondary intention. OUTCOME MEASURES AND COMPARISONS: The rate of pin tract infection and surgical site infection following primary closure of external fixator pin sites relative to patients whose pin sites were allowed to heal through secondary intention. RESULTS: In total, 256 patients were evaluated: 143 patients (406 pin sites) in the primary closure group and 113 patients (340 in sites) in the secondary closure group. The average age was 49 ± 16 years. Sixty-five percent of included patients were male. There was no difference in pin tract infections between cohorts (primary = 0.5%, secondary = 1.5%, P = 0.26). External fixator duration in the primary closure group was 11.5 ± 8.4 days and 13.0 ± 8.1 days in the secondary closure group (P = 0.15). There was a greater rate of surgical site infections in the secondary intention cohort (15.9% vs. 7.7%, P = 0.047). CONCLUSIONS: There was no difference in pin site infection rate after primary pin site closure relative to patients who were allowed to heal through secondary intention. Furthermore, there was a lower rate of surgical site infection after primary closure. These results challenge the dogma of secondary closure for ex fix pin sites, suggesting that debridement and primary closure is a safe option for management of external fixator pin sites and may impart benefit in decreasing infection risk. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Plate fixation of inferior ramus in pubis-ischium ramus improves mechanical stability in Tile B pelvic injures: a cadaveric biomechanical analysis and early clinical experience.

BACKGROUND: Management of inferior ramus of the pubis-ischium ramus remains controversial, and related research is sparse. The main intention of this study is to describe the biomechanical and clinical outcomes of pubis-ischium ramus fractures in Tile B pelvic injuries and to identify the feasibility and necessity of fixation of the inferior ramus of the pubis-ischium ramus. METHODS: This study comprised two parts: a biomechanical test and a retrospective clinical study. For the biomechanical tests, Tile B-type pelvic injuries were modeled in six cadaver specimens by performing pubis-ischium osteotomies and disruption of the anterior and interosseous sacroiliac ligaments. The superior and/or inferior rami of the pubis-ischium ramus were repaired with reconstruction plates and separated into three groups (A, B, and C). Specimens were placed in the standing position and were loaded axially with two-leg support for three cycles at 500 N. The displacements of sacroiliac joints at osteotomy were measured with Vernier calipers and compared using statistical software. To investigate the clinical outcomes of this technique, 26 patients were retrospectively analyzed and divided into a superior ramus fixation group (Group D) and a combined superior and inferior ramus of the pubis-ischium ramus fixation group (Group E). The main outcome measures were time of operation, blood loss, postoperative radiographic reduction grading, and functional outcomes. RESULTS: In the vertical loading test, Group E showed better pelvic ring stability than Group D (P < 0.05). However, the shift of the sacroiliac joints was almost identical among the three groups. In our clinical case series, all fractures in Group E achieved bony union. Group E demonstrated earlier weight-bearing functional exercise (2.54 ± 1.45 vs 4.77 ± 2.09; P = 0.004), earlier bony union (13.23 ± 2.89 vs 16.55 ± 3.11; P = 0.013), and better functional outcomes (89.77 ± 7.27 vs 82.38 ± 8.81; P = 0.028) than Group D. The incidence of sexual dysfunction was significantly lower in Group E than that in Group D (2/13 vs 7/13; P = 0.039). Bone nonunion occurred in two patients in Group D, and two patients in Group E had heterotopic ossification. None of the patients exhibited wound complications, infections, implant failures, or bone-implant interface failures. CONCLUSIONS: Fixation of the inferior ramus of a pubis-ischium ramus fracture based on conventional fixation of the anterior pelvic ring is mechanically superior in cadaveric Tile B pelvic injury and shows rapid recovery, good functional outcomes, and low incidence of complications.

Pediatric-Specific Lesions in Unstable Pelvic Ring Fractures of Skeletally Immature Children: Impact on Diagnosis and Management Decisions.

Surgical fixation of pediatric pelvic ring injuries is gaining popularity to avoid the poor long-term outcomes of pelvic asymmetry. The surgical techniques and fixation choices depend on the individual injuries affecting the anterior and posterior pelvic ring areas. The immature bony pelvis of young children has anatomic differences including soft bones, elastic ligaments, and the presence of growth centers. Understanding the unique pediatric lesions with unstable pelvic fractures is essential for treatment decisions. Anterior lesions include pubic symphysis disruption through the pubic apophysis, single ramus fractures, pubic rami fractures through the triradiate cartilage, and/or the ischiopubic synchondrosis; ischiopubic ramus infolding injury; or the unstable superior and inferior quadrant lesions. Posterior pelvic lesions include iliac wing infolding and sacroiliac joint dislocation or transiliac (crescent) fracture/dislocations through the iliac apophysis growth plate. Pubic symphysis and sacroiliac disruptions are physeal injuries in children, and they have excellent healing potential. External fixation is an ideal choice for anterior ring fixation including bony and pubic symphysis injuries. Posterior lesions are mostly sacroiliac joint disruptions with iliac apophysis separation that can serve as a landmark for vertical displacement correction. Posterior lesions can be treated by percutaneous iliosacral screw fixation or open reduction techniques.

A Cost-Affordable Methodology of 3D Printing of Bone Fractures Using DICOM Files in Traumatology.

Three-dimensional (3D) printing has gained popularity across various domains but remains less integrated into medical surgery due to its complexity. Existing literature primarily discusses specific applications, with limited detailed guidance on the entire process. The methodological details of converting Computed Tomography (CT) images into 3D models are often found in amateur 3D printing forums rather than scientific literature. To address this gap, we present a comprehensive methodology for converting CT images of bone fractures into 3D-printed models. This involves transferring files in Digital Imaging and Communications in Medicine (DICOM) format to stereolithography format, processing the 3D model, and preparing it for printing. Our methodology outlines step-by-step guidelines, time estimates, and software recommendations, prioritizing free open-source tools. We also share our practical experience and outcomes, including the successful creation of 72 models for surgical planning, patient education, and teaching. Although there are challenges associated with utilizing 3D printing in surgery, such as the requirement for specialized expertise and equipment, the advantages in surgical planning, patient education, and improved outcomes are evident. Further studies are warranted to refine and standardize these methodologies for broader adoption in medical practice.

Fluoroscopy guided teardrop technique for open trans-muscular iliac screw placement and open reduction maneuvers during modified triangular spinopelvic fixation for unstable U-shaped sacral and tile C pelvic traumas: technical note.

Unstable traumas of the spinopelvic junction, which include displaced U-shaped sacral fractures (Roy-Camille type 2 and type 3) and Tile C vertical shear pelvic ring disruptions, occur in severe traumas patients following high speed traffic accident or fall from a height. These unstable traumas of the spinopelvic junction jeopardize one's ability to stand and to walk by disrupting the biomechanical arches of the pelvis, and may also cause cauda equina syndrome. Historically, such patients were treated with bed rest and could suffer a life-long burden of orthopedic and neurological disability. Since Schildhauer pioneer work back in 2003, triangular spinopelvic fixation, whether it is performed in a percutaneous fashion or by open reduction and internal fixation, allows to realign bone fragments of the spinopelvic junction and to resume walking within three weeks. Nevertheless, such procedure remains highly technical and it not encountered very often, even for spine surgeons working in high-volume level 1 trauma centers. Hence, this visual technical note aims to provide a few tips to guide less experience surgeons to complete this procedure safely.

Perioperative impact of ultrasound-guided ilioinguinal and iliohypogastric nerve blocks in patients undergoing pelvic fracture surgery.

Pelvic fractures present a severe and complex clinical challenge. This study aimed to compare ultrasound-guided ilioinguinal (IIN) and iliohypogastric nerve (IHN) blocks with conventional general anesthesia (GA) in patients undergoing internal fixation surgery for pelvic fractures. A retrospective analysis was conducted on 100 patients equally divided into ultrasound-guided and control groups. The study monitored hemodynamics, intraoperative anesthesia drug usage, postoperative pain levels, and the incidence of adverse reactions between the 2 groups. The ultrasound-guided group underwent ultrasound-guided IHN and IIN blocks combined with GA. The ultrasound-guided group exhibited significant advantages for hemodynamic measurements at specific time points, lower consumption of Propofol and Remifentanil, and reduced pain intensity across all evaluated time intervals (P < .05). The incidence rate of adverse reactions was significantly lower in the ultrasound group (P = .016). Ultrasound-guided anesthesia is a superior alternative to conventional GA for managing pelvic fractures through internal fixation surgery. It offers advantages in terms of hemodynamic stability, drug consumption, postoperative pain management, and adverse reaction reduction.

Biomechanical Comparison of Fixation Methods for Posterior Wall Fractures of the Acetabulum: Conventional Reconstruction Plate vs. Spring Plate vs. Variable Angle Locking Compression Plate.

Background and Objectives: Acetabular fractures, though infrequent, present considerable challenges in treatment due to their association with high-energy trauma and poor prognoses. Posterior wall fractures, the most common type among them, typically have a more favorable prognosis compared to other types. Anatomical reduction and stable fixation of the posterior wall are crucial for optimal treatment outcomes. This study aimed to biomechanically compare three commonly used fixation methods for posterior wall fractures of the acetabulum-a conventional reconstruction plate, a spring plate, and a 2.7 mm variable angle locking compression plate (VA-LCP). Materials and Methods: The study utilized 6 fresh-frozen cadavers, yielding 12 hemipelvises free from prior trauma or surgery. Three fixation methods were compared using a simple acetabulum posterior wall fracture model. Fixation was performed by an orthopedic specialist, with prebending of plates to minimize errors. Hemipelvises were subjected to quasi-static and cyclic loading tests, measuring fracture gap, stiffness, and displacement under load. Results: It showed no significant differences in fracture gap among the three fixation methods under cyclic loading conditions simulating walking. However, the conventional reconstruction plate exhibited a greater stiffness compared to the spring and variable angle plates. Fatigue analysis revealed no significant differences among the plates, indicating a similar stability throughout cyclic loading. Despite differences in stiffness, all three fixation methods demonstrated adequate stability under loading conditions. Conclusions: While the conventional reconstruction plate demonstrated a superior stiffness, all three fixation methods provided sufficient stability under cyclic loading conditions similar to walking. This suggests that postoperative limitations are unlikely with any of the three methods, provided excessive activities are avoided. Furthermore, the variable angle plate-like the spring plate-offers an appropriate stability for fragment-specific fixation, supporting its use in surgical applications. These findings contribute to understanding the biomechanical performance of different fixation methods for acetabular fractures, facilitating improved surgical outcomes in challenging cases.

Effect of different lumbar-iliac fixation and sacral slope for Tile C1.3 pelvic fractures: a biomechanical study.

BACKGROUND: Lumbar-iliac fixation (LIF) is a common treatment for Tile C1.3 pelvic fractures, but different techniques, including L4-L5/L5 unilateral LIF (L4-L5/L5 ULIF), bilateral LIF (BLIF), and L4-L5/L5 triangular osteosynthesis (L4-L5/L5 TOS), still lack biomechanical evaluation. The sacral slope (SS) is key to the vertical shear of the sacrum but has not been investigated for its biomechanical role in lumbar-iliac fixation. The aim of this study is to evaluate the biomechanical effects of different LIF and SS on Tile C1.3 pelvic fracture under two-legged standing load in human cadavers. METHODS: Eight male fresh-frozen human lumbar-pelvic specimens were used in this study. Compressive force of 500 N was applied to the L4 vertebrae in the two-legged standing position of the pelvis. The Tile C1.3 pelvic fracture was prepared, and the posterior pelvic ring was fixed with L5 ULIF, L4-L5 ULIF, L5 TOS, L4-L5 TOS, and L4-L5 BLIF, respectively. Displacement and rotation of the anterior S1 foramen at 30° and 40° sacral slope (SS) were analyzed. RESULTS: The displacement of L4-L5/L5 TOS in the left-right and vertical direction, total displacement, and rotation in lateral bending decreased significantly, which is more pronounced at 40° SS. The difference in stability between L4-L5 and L5 ULIF was not significant. BLIF significantly limited left-right displacement. The ULIF vertical displacement at 40° SS was significantly higher than that at 30° SS. CONCLUSIONS: This study developed an in vitro two-legged standing pelvic model and demonstrated that TOS enhanced pelvic stability in the coronal plane and cephalad-caudal direction, and BLIF enhanced stability in the left-right direction. L4-L5 ULIF did not further improve the immediate stability, whereas TOS is required to increase the vertical stability at greater SS.

Efficacy of intramedullary bridge fixation for midshaft clavicle fractures: a retrospective analysis of a novel technique.

BACKGROUND: The aim of this study was to explore the efficacy of a novel intramedullary fixation technique using the ortho-bridge system (OBS) for midshaft clavicle fractures. METHODS: A total of 63 patients were included in this study: 35 underwent plate internal fixation (LP group) and 28 underwent OBS intramedullary fixation (OBS group). Surgical time, intraoperative blood loss, incision length, fracture healing time, removal of the internal fixation agent, visual analog scale (VAS) score for shoulder pain, Constant-Murley shoulder score and complication occurrence were compared between the two groups. RESULTS: Preoperative general data, such as sex, age and fracture type, were not significantly different between the two groups (P > 0.05). However, the OBS group exhibited better outcomes than the LP group exhibited in terms of surgical time, intraoperative blood loss and total incision length (P < 0.05). Additionally, the OBS group exhibited a significantly shorter fracture healing time and internal-fixation removal time than the LP group exhibited (P < 0.05). The VAS scores on postoperative day 1, week 1, month 1 and month 3 were lower in the OBS group than in the LP group (P < 0.05). Furthermore, the Constant-Murley shoulder scores at 1, 3, and 6 months postoperatively were higher in the OBS group than in the LP group (P < 0.05), with no significant difference at 1 year after surgery (P > 0.05). None of the patients in the OBS group experienced scarring of the surgical incision, and 6 patients in the LP group experienced scarring of the surgical incision. Finally, the complication incidence in the OBS group was lower than that in the LP group. CONCLUSION: For midshaft clavicle fractures, OBS intramedullary fixation is better than locking-plate internal fixation because it led to less trauma, a faster recovery, better efficacy, and better esthetic outcomes and comfort. Therefore, this technique may have potential as a novel treatment for midshaft clavicle fractures. LEVEL OF EVIDENCE: III, retrospective observational study.

[Clinical and functional evaluation of pediatric patients with pelvic fracture treated in a third level Hospital]. / Evaluación clínica y funcional de pacientes pediátricos con fractura de pelvis tratados en un Hospital de Tercer Nivel.

INTRODUCTION: pelvic fracture in children is considered one of the most important injuries due to its high mortality. They are rare, but have a major impact on patients' functional outcomes. OBJECTIVE: to evaluate the clinical evolution and functional grade in pediatric patients with pelvic fractures who have already been treated, either conservatively or surgically. MATERIAL AND METHODS: descriptive-cross-sectional-retrospective study. Sample of 24 patients, aged five to 16 years with pelvic fracture, treated from 2016 to 2021. Clinical and functional outcome was assessed using the Barthel index and hip range of motion, as well as surgical or conservative treatment, accompanying lesions and injury mechanism. RESULTS: to find out if there is an association between the Torode and Zieg classifications with the Barthel index and hip range of motion, an association analysis was performed with the 2 statistic, obtaining a 2 value = 19.213. with p = 0.004 for the Barthel index and a 2= 14.253 with p = 0.0026 for hip ranges of motion; these results indicate that there is statistically significant association. CONCLUSION: the most frequent type of pelvic fracture in pediatric patients treated is type III on the Torode and Zieg scale, which according to the Barthel index is associated with a degree of independence and complete hip mobility arches, so the clinical and functional outcome in these patients is high in severe injuries.

INTRODUCCIÓN: la fractura de pelvis en edad pediátrica es considerada de las lesiones más importantes debido a su alta mortalidad; son poco frecuentes, pero tienen gran impacto en el resultado funcional de los pacientes. OBJETIVO: evaluar la evolución clínica y grado funcional en niños con fracturas de pelvis tratados de forma conservadora o quirúrgica. MATERIAL Y MÉTODOS: estudio descriptivo-transversal-retrospectivo. Muestra de 24 pacientes, de cinco a 16 años de edad, con fractura de pelvis, tratados del 2016 al 2021. Se valoró el resultado clínico y funcional mediante el índice de Barthel y arcos de movilidad de cadera, tratamiento quirúrgico o conservador, lesiones acompañantes y mecanismo de lesión. El análisis estadístico se realizó con el software IBM SPSS Statistics®. RESULTADOS: se realizó un análisis de asociación mediante 2 entre las clasificaciones de Torode y Zieg con el índice de Barthel y arcos de movilidad de cadera, obteniendo un valor de 2 = 19.213 con p = 0.004 para índice de Barthel y un valor de 2= 14.253 con p = 0.0026 para arcos de movilidad de cadera; estos resultados indican que hay una asociación estadísticamente significativa. CONCLUSIÓN: el tipo de fractura de pelvis más frecuente en pacientes tratados es el tipo III en la escala de Torode y Zieg, la cual, según el índice de Barthel, se asocia con un grado de independencia y arcos de movilidad de cadera completos, por lo que el resultado clínico y funcional en estos pacientes es alto en lesiones severas.

[Trans-scapho-perilunar fracture-dislocation: a case report]. / Fractura-luxación transescafo-perilunar: reporte de un caso clínico.

Trans-scaphoid perilunate fractures-dislocations are rare injuries caused by high-energy trauma of the wrist. Diagnosis is based on medical history, physical examination, and tools such as radiographs, computed tomography scan, and magnetic resonance imaging. Early treatment consists of closed reduction and casting to stabilize the limb. Definitive treatment is surgical and includes bone and soft tissue repair. A case of trans-scaphoid perilunate fracture-dislocation is presented, along with diagnosis, management and outcome.

Las fracturas-luxaciones transescafo-perilunares son lesiones infrecuentes causadas por impactos de alta energía hacia la muñeca. El diagnóstico se basa en la historia clínica, exploración física y herramientas como la radiografía, la tomografía computarizada y la resonancia magnética. El manejo inmediato consiste en una reducción cerrada e inmovilización para estabilizar la extremidad. El tratamiento definitivo es de carácter quirúrgico e incluye la reparación ósea y de tejidos blandos. Se presenta un caso de fractura-luxación transescafo-perilunar, su diagnóstico, manejo y evolución.

Fracture related infection and sepsis in orthopedic trauma: A review.

Trauma is a leading cause of death in the United States for people under 45. Amongst trauma-related injuries, orthopedic injuries represent a significant component of trauma-related morbidity. In addition to the potential morbidity and mortality secondary to the specific traumatic injury or injuries sustained, sepsis is a significant cause of morbidity and mortality in trauma patients as well, and infection related to orthopedic trauma can be especially devastating. Therefore, infection prevention and early recognition of infections is crucial to lowering morbidity and mortality in trauma. Risk factors for fracture-related infection include obesity, tobacco use, open fracture, and need for flap coverage, as well as fracture of the tibia and the degree of contamination. Timely administration of prophylactic antibiotics for patients presenting with open fractures has been shown to decrease the risk of fracture-related infection, and in patients that do experience sepsis from an orthopedic injury, prompt source control is critical, which may include the removal of implanted hardware in infections that occur more than 6 weeks from operative fixation. Given that orthopedic injury constitutes a significant proportion of traumatic injuries, and will likely continue to increase in number in the future, surgeons caring for patients with orthopedic trauma must be able to promptly recognize and manage sepsis secondary to orthopedic injury.

Force/position tracking control of fracture reduction robot based on nonlinear disturbance observer and neural network.

BACKGROUND: For the fracture reduction robot, the position tracking accuracy and compliance are affected by dynamic loads from muscle stretching, uncertainties in robot dynamics models, and various internal and external disturbances. METHODS: A control method that integrates a Radial Basis Function Neural Network (RBFNN) with Nonlinear Disturbance Observer is proposed to enhance position tracking accuracy. Additionally, an admittance control is employed for force tracking to enhance the robot's compliance, thereby improving the safety. RESULTS: Experiments are conducted on a long bone fracture model with simulated muscle forces and the results demonstrate that the position tracking error is less than ±0.2 mm, the angular displacement error is less than ±0.3°, and the maximum force tracking error is 26.28 N. This result can meet surgery requirements. CONCLUSIONS: The control method shows promising outcomes in enhancing the safety and accuracy of long bone fracture reduction with robotic assistance.

Antegrade anterior column acetabulum fracture fixation with cannulated compression headless screws-A biomechanical study on standardized osteoporotic artificial bone.

PURPOSE: Due to the increase in life expectancy and high-energy traumas, anterior column acetabular fractures (ACFs) are also increasing. While open reduction and internal fixation (ORIF) is still the standard surgical procedure, minimally invasive, percutaneous fixation of osteoporotic acetabulum fractures (AF) are growing in popularity. The aim of this biomechanical study was to evaluate the biomechanical competence following antegrade fixation with a standard screw versus a cannulated compression headless screw. METHODS: Eight anatomical osteoporotic composite pelvises were given an anterior column fracture. Two groups of eight specimens each (n = 8) for fixation with either a 6.5 mm cannulated compression headless screw in group Anterior Acetabulum Canulated Compression Headless Screw (AACCH), or with a 6.5 mm partially threaded cannulated screw in group Anterior Acetabulum Standard Screw (AASS) where compared. Each specimen was biomechanically loaded cyclically at a rate of 2 Hz with monotonically increasing compressive load until failure. Motions were assessed by means of optical motion tracking. RESULTS: Initial construct stiffness trended higher in group AACCH at 152.4 ± 23.1 N/mm compared to group AASS at 118.5 ± 34.3 N/mm, p = 0.051. Numbers of cycles and corresponding peak load at failure, were significantly higher in group AACCH at 6734 ± 1669 cycles and 873.4 ± 166.9 N versus group AASS at 4440 ± 2063 cycles and 644.0 ± 206.3 N, p = 0.041. Failure modes were breakout of the screws around the proximal entry point. CONCLUSION: From a biomechanical perspective, group AACCH was associated with superior biomechanical competence compared to standard partially threaded cannulated screws and could therefore be considered as valid alternative for fixation of anterior acetabulum fractures.