Displacement Of Fragments Research Articles

Hydropneumothorax in an Isolated Midshaft Clavicle Fracture

Background: Clavicle fractures are the fourth most common fracture. These fractures are either managed conservatively or surgically. Pneumothorax is a rare complication of clavicle fractures and potentially can be missed if this rare complication is not known. Case Report: A 76-year-old female presents with a 2-day history of pain and bruising over the right clavicular prominence following a fall from a standing height. Subsequent radiographs show the development of pneumothorax, despite having no respiratory symptoms. Discussion: Pneumothorax as a complication of isolated clavicle fractures is rare, with no case reports of hydropneumothorax in the literature. We hypothesize that the posterior displacement of the clavicle fragment penetrated the lung pleura resulting in the pneumothorax. We propose routine chest radiographs for patients presenting with clavicle fractures to rule out pneumothorax for the three reasons below. (1) Clinical features of pneumothorax might not be present upon patient’s initial presentation, especially if they are relatively healthy individuals(2) Adequate pre-operative management if the patient is for surgical intervention (3) Assessment of surgical complications if the patient is for surgical intervention as iatrogenic pneumothorax is a potential complication of surgical fixation. Conclusion: Thorough clinical examination and radiological evaluation should be performed with the diagnosis of pneumothorax in mind when a patient presents with a clavicle fracture to ensure early diagnosis and treatment of this life-threatening complication. Keywords: Clavicle fracture, pneumothorax, hydropneumothorax.

Specifics of imaging in traumatic lesions of the shoulder joint

Background. The shoulder joint is one of the most complex and functionally important joints in the human body. Also, the shoulder joint is one of the most traumatic areas of the human body. Each type of injury of the joint requires a special approach to radiological diagnosis, as it has its own characteristic signs on radiographs that must be recognized and correctly interpreted. Purpose of the study: To consider methods and features of interpretation of radiographs in the context of various types of damage. Material and methods: Systematic analysis of existing scientific publications, studies and clinical observations on this topic. To search for relevant information, online databases of scientific articles were used, including PubMed, eLibrary MEDLINE, Google Scholar and others. In addition, data from meta-analyses and literature reviews, clinical guidelines in radiology and osteopathy were used. Results and discussion. Correct classification helps determine diagnostic and treatment strategies, ensuring effective and timely medical care for injured patients. Computed tomography allows to obtain layer-by-layer images of the joint, which provide a more accurate determination of the nature of the injury, the presence of fractures or soft tissue damage. MRI is often used to further diagnose shoulder injuries. MR-arthrography is commonly used to evaluate clinically unstable patients. Conclusion.Early radiation and magnetic resonance diagnostics make it possible to effectively establish treatment tactics and provide the necessary medical care. It should be emphasized that the use of radiography in combination with other imaging methods makes it possible to increase the accuracy of the diagnosis and determine parameters such as displacement of bone fragments or soft tissue damage

Combined osteosynthesis for tibial shaft fracture treatment

Introduction Widespread use of intramedullary and extramedullary implants, as well as external fixation devices, has demonstrated that current surgical methods are not always successful.The study aimed to assess the efficiency of a combination of transosseous osteosynthesis with intramedullary reinforcement using elastic titanium hydroxyapatite-coated rods (HA-rods) in long bone fracture treatment.Material and methods Medical records of 40 patients aged from 18 to 55 years with closed diaphyseal tibia fractures of A1-A3 type (AO/ASIF) treated with the Ilizarov transosseous osteosynthesis method combined with intramedullary elastic HA-coated wires were analysed. Result Ilizarov fixator removal was performed on average 45.3 ± 14.7 days after surgery. Radiological signs of bone union (immature callus, patterns of periosteal and endosteal stratifications overlapping the fracture line) were visible by week 3 to 4.Discussion Соmbination of the external fixator and intramedullary elastic HA-coated wires overcomes shortcomings of both external and internal means of fixation. External osteosynthesis provides advantages of the Ilizarov method: preservation of blood supply, absence of soft tissue injury, joint function and early weightbearing. Elastic intramedullary wires do not injure a. nutricia and mechanically stimulate endosteal and periosteal bone formation.Conclusion The advantages of combined osteosynthesis provide reduction of Ilizarov apparatus fixation time, reduction in the number of wires and half-pins in the frame assembly, stimulation of bone callus formation and prevention of secondary bone fragment displacement.

Prevention of ankle joint deformities in children on the side of fibular graft intake for microsurgical transposition

BACKGROUND: Reconstructive operations of the musculoskeletal system in children may require the removal of a massive autograft for microsurgical bone grafting. The traditional donor site is the diaphyseal part of the fibula. In the late postoperative period, these patients may develop complications such as a valgus deformity of the ankle joint on the side of the donor fibular defect.
 AIM: To analyze the effectiveness of surgical methods for the prevention of hallux valgus of the ankle joint after free transplantation of a fragment of the fibula to replace limb-bone defects in children.
 MATERIALS AND METHODS: The treatment results of 11 patients aged 11–16 years (6 girls and 5 boys), in whom an autograft from the fibular diaphysis was used to replace defects in long tubular bones were analyzed. Two patients had a femoral defect as a result of previously transferred hematogenous osteomyelitis. A congenital false joint of the femur was found in 2 patients, bones of the lower leg in 6, and the ulna in 1. The distal fragment of the resected fibula was stabilized by an autograft from the iliac bone, in eight and three cases at the level of the diaphysis and metaphysis of the specified fragment, respectively. The size of the resected fragment in % of the total length of the fibula and the level of distal osteotomy were considered. The presence and magnitude of the proximal displacement of the fragment and the position of the ankle joint gap were evaluated at least 5 years after surgery.
 RESULTS: In this study, ≥5 years after the intervention, proximal displacement of the distal fragment of the fibula was absent in only one patient. In the remaining 10, the displacement value did not exceed 3.5 mm. Valgus deformity in the ankle joint of 5° from the initial position developed in two patients. Its progression was prevented by temporary hemiepiphysis of the distal epiphysis of the tibia using a 4.0-mm diameter spongiose screw, whereas in up to 16 months, the valgus deformity progression stopped and decreased to initial values.
 CONCLUSIONS: Fibular resection in the optimal variant should preserve the distal part of the bone as much as possible, and the stability of the ankle joint increases with synostosis of the shin bones in the distal diaphyseal section without bringing the bones closer together. When a clinically significant valgus deformity appears (5° from the initial position) with the preservation of the function of the distal growth zone of the tibia, the use of temporary transphyseal hemiepiphysiodesis of the tibia for correction is optimal.

Do not Miss a Pediatric Lateral Condyle Fracture- A Case Based Description of Neglected Case Managed with Good Outcome

Background: Lateral Condyle Fractures are the second most common fracture amongst the pediatric elbow fractures, which is usually neglected commonly due to parents not seeking timely medical help or clinician missing the diagnosis with lack of knowledge or understanding. Case Presentation: A 3-year-old female was presented in the outpatient department with outward bowing of the right elbow following a history of FOOSH injury more than a month back. Clinical examination showed gross valgus deformity with an increased carrying angle with thickened and irregular lateral condyle on examination. Adiograph of the elbow showed nonunion of the lateral humeral condyle with lateral displacement and malrotation of the fracture fragment. The carrying angle of the affected side was 50º and Baumann’s angle on affected side was 40º. A CT scan also showed displaced fracture of lateral epicondyle of right humerus. Patient was treated successfully with Open Reduction and Internal Fixation (ORIF) with Kirschner (k) wires. On follow up, the patient had significant improvement with the correction of valgus deformity and overall improvement in the elbow range of movements.

Assessment of biomechanical properties of the new two-hole miniplate internal fixation for bony mallet finger treatment by finite element analysis

Surgery is highly recommended for a bony mallet finger when the fracture fragment involves greater than one-third of the articular surface. K-wire based and plated-based internal fixation are widely used for mallet fracture. However, the outcomes of different surgical treatment options make the treatment of the bony mallet finger controversial due to frequent complications. The two-hole miniplate is a new and promising plate-based internal fixation treatment for the bony mallet finger with low complication rates in recent years. The aim of this study was to evaluate the biomechanical parameters (von Mises stress, strain and deformation) of the two-hole miniplate fixation compared to the traditional K-wire-based fixation using finite element analysis (FEA). Further, the biomechanical parameters of each part of the two-hole miniplate internal fixation were also analyzed. The results indicated that the two-hole miniplate model had the minimum von Mises stress value and the displacement of fracture fragment was less than 30 µm. The two-hole miniplate had an apparent compression effect on the avulsion fracture and inhibited the fracture displacement. This study would provide further guidance for clinical application in using the two-hole miniplate internal fixation.

Comparative study of mechanical performance of various fixation constructs in multifragmentary distal humeral shaft fracture: a finite element analysis.

There has been no scientific mechanical assessment demonstrating the optimal fixation technique in multifragmentary fractures of the distal humeral shaft. The purpose of the present study was to compare the biomechanical performance of 5 fixation constructs as used in minimally invasive plating osteosynthesis (MIPO) for distal humeral shaft fractures. Three-dimensional (3D) humerus model with 20mm distal humeral shaft fracture gap simulating multifragmentary fracture was created from computed tomography data and virtually fixed by 5 fixation techniques as MIPO, i.e., anterior narrow dynamic compression plate (DCP), anterior narrow locking compression plate (LCP), anterior reversed proximal humeral internal locking system (R-PHILOS), extra-articular distal humerus locking compression plate (LCP-EADH), and anteromedial LCP. All constructs were biomechanically tested under 6 loading conditions by means of finite element analysis, i.e., 250-N axial compression, 7.5-Nm internal rotation, 7.5-Nm external rotation, 10-Nm posterior bending, 10-Nm valgus rotation, and 10-Nm varus rotation. In addition, A 3D model of each construct was fabricated as 3D printed models. Fixations were applied to the 3D printing model which were later mechanically tested to validate the FE results. EQV stress exhibited on anterior narrow LCP and anterior R-PHILOS were comparable which were lower than other constructs under axial compression and valgus-varus bending. Anterior R-PHILOS produced lower EQV stress than other constructs under internal-external rotation and posterior bending. On the whole, R-PHILOS demonstrated a comparable fracture displacement to those LCP with anterior or anteromedial approaches, that achieved the lowest displacement values. In addition, the experimental mechanical test values shared a correlation with the FE model results. Overall, the anterior R-PHILOS was considered as a potential candidate for multifragmentary distal humeral shaft fractures. It demonstrated efficacious biomechanical performance in terms of implant stress and distal fragment displacement.

Biomechanics and finite element analysis comparing posterior T-plates with LCP for fixation of posterolateral tibial plate fractures.

Objective: The treatment for posterolateral tibial plateau fractures (PTPF) have been subjects of controversy. We conducted a study to improve the fixation of PTPF through a lateral approach. Methods: We utilized 40 synthetic tibias and categorized the fracture models into five groups based on the locking compression plate (LCP) and T-distal radius plate (TPP) via various forms of fixation with screws through the posterolateral (PL) fracture fragments. I: Two-screw fixation using two locking screws (LPTL). Ⅱ: Two-screw fixation with both variable angle locking screws (LPTV). Ⅲ: One-screw fixation with one locking screw (LPOL). Ⅳ: One-screw fixation with one locking screw and two anteroposterior lag screws (LPOLTL). Ⅴ: a distal radius plate with three locking screws (TPP). Biomechanical tests were conducted to observe the axial compression displacement of the PL fracture fragments at force levels of 250N, 500N, and 750N, as well as to determine the failure load and the axial stiffness for each respective group. Results: Under a 750N load condition, the displacements within the five experimental groups exhibited the following trend: Ⅴ < Ⅱ < Ⅰ< Ⅳ < Ⅲ. However, there were no significant differences between Group V and Group II, Group I and Group IV (p > 0.05), and only Group Ⅲ demonstrated a displacement exceeding 3mm. The failure load and the axial stiffness exhibited the same trend. Conversely, statistical significance was identified among the remaining group compared with Group Ⅲ (p < 0.05). Regarding the finite element analysis, the maximum displacements for the five models under the load of 750N exhibited the following trend: Ⅴ < Ⅱ < Ⅰ< Ⅳ < Ⅲ. The following trends were observed in maximum von Mises stresses for these models under the load of 750N: Ⅴ < Ⅱ < Ⅳ< Ⅰ < Ⅲ. Conclusion: It is crucial to address the inadequate mechanical strength associated with single screw fixation of LCP for fixing PL fractures in a clinical setting. The biomechanical strength of two-screw fixation surpasses that of single-screw fixation. Introducing variable-angle screws can further enhance the fixation range. Furthermore, the addition of two lag screws threaded from anterior to posterior can compensate the mechanical stability, when PL fracture is fixed with single screw in clinic.

Management of frontal sinus fractures requiring surgical intervention: An analysis of a case series.

&lt;b&gt;&lt;br&gt;Introduction:&lt;/b&gt; Isolated frontal bone fractures constitute 5-15% of traumatic facial fractures cases, with frontal sinus fractures categorized into anterior wall, posterior wall, or complex fractures. The approach is tailored to fracture type and bone fragment displacement. This paper presents the summary of surgical management in patients with isolated and complex fractures of the anterior wall of the frontal sinus.&lt;/br&gt; &lt;b&gt;&lt;br&gt;Material and Methods:&lt;/b&gt; Five patients with different frontal sinus fractures were treated surgically. The same management protocol - diagnosis and surgical intervention was implemented in all cases The retrospective analysis included fracture assessment, surgical approach, and long-term outcomes evaluation.&lt;/br&gt; &lt;b&gt;&lt;br&gt;Results:&lt;/b&gt; The most common cause of fractures was falls, while two complex fractures involved the anterior and posterior walls. External approach, bone fragment removal, endoscopy, and external stabilization were employed in all cases. One patent required delayed revision surgery due to retaining metallic foreign body. Follow-up radiological examinations showed proper healing and cosmetic outcomes were satisfactory in all of the cases.&lt;/br&gt; &lt;b&gt;&lt;br&gt;Conclusion:&lt;/b&gt; Surgical management of isolated fractures of the frontal sinus anterior wall, involving bone fragment removal, realignment, and endoscopy, yielded satisfactory functional and cosmetic outcomes without internal or external stabilization. Long-term monitoring and symptom assessment are crucial, especially in cases with penetrating injuries and foreign body risk.&lt;/br&gt.

Injury to the posterior malleolus in Maisonneuve fractures

PurposeThe aim of this study was to describe the incidence and a complex pathoanatomy of posterior malleolus fractures in a Maisonneuve fracture.MethodsThe study included 100 prospectively collected patients with a complete clinical and radiological documentation of an ankle fracture or fracture-dislocation including a fracture of the proximal quarter of the fibula.ResultsA posterior malleolus fracture was identified in 74 patients, and in 27% of these cases it carried more than one quarter of the fibular notch. Displacement of the posterior fragment by more than 2 mm was shown by scans in 72% of cases. Small intercalary fragments were identified in 43% of cases. Fractures of the Tillaux–Chaput tubercle were identified in 20 patients.ConclusionOur study has proved a high rate of posterior malleolus fractures associated with a Maisonneuve fracture, and documented their considerable variability in terms of involvement of the fibular notch, tibiotalar contact area, direction of displacement and frequency of intercalary fragments. Of no less importance is a combination of Tillaux–Chaput fractures with a Maisonneuve fracture.

ROTATOR CUFF TEAR IN FRACTURE SHOULDER DISLOCATION

IntroductionWe aim to assess whether radiographic characteristics of the greater tuberosity fragment can predict rotator cuff tears inpatients with anterior shoulder dislocations combined with an isolated fracture of the greater tuberosity.MethodsA retrospective single-centre case series of 61 consecutive patients that presented with anterior shoulder dislocations combined with an isolated fracture of the greater tuberosity between January 2018 and July 2022. Inclusion criteria: patients with atraumatic anterior shoulder dislocation associated with an isolated fracture of the greater tuberosity with a minimum follow-up of 3-months. Exclusion criteria: patients with other fractures of the proximal humerus or glenoid. Rotator cuff tears were diagnosed using magnetic resonance or ultrasound imaging. Greater tuberosity fragment size and displacement was calculated on plain radiographs using validated methods.ResultsThe case series was composed of 22 men and 39 women with a mean age of 65 years (29 - 91 years). The mean follow-up was 15months and median follow up 8.5 months (3 – 60 months). A rotator cuff tear was diagnosed in 14 patients (16%) and involved the supraspinatus (13), infraspinatus (4) and subscapularis (2). Full-thickness tears occurred in 6 patients and partial-thickness tears in 8patients. The mean time from initial injury to rotator cuff tear diagnosis was 5 months (2 – 22 months).The mean greater tuberosity fragment length was 23.4 mm in rotator cuff tear patients versus 32.6 mm in those without a tear (p = 0.006, CI: -15 - -2). The mean greater tuberosityfragment width was 11.1 mm in rotator cuff tear patients versus 17.8 mm in those without a tear (p = 0.0004, CI: -10 - -2). There was no significant difference in the super inferior and anteroposterior fragment displacement between the two groups.ConclusionIn patients with shoulder dislocations combined with an isolated fracture of the greater tuberosity, rotator cuff tears are associated with a smaller sized greater tuberosity fragment.

Biomechanics and finite element analysis of a novel plate designed for posterolateral tibial plateau fractures via the anterolateral approach

Surgical management of posterolateral tibial plateau (PLTP) fractures is challenging. One reason for this challenge is the lack of suitable internal fixation devices. Our aim was to introduce a novel plate via the anterolateral approach for managing PLTP fractures. The biomechanical testing and finite element analysis (FEA) were performed. PLTP fracture models were created using synthetic tibias (n = 10 within each group). These models were randomly assigned to three groups (groups A-C) and fixed with the lateral locking plate, the posterior buttress plate, and the novel plate, respectively. The vertical displacement of the posterolateral fragments was evaluated using biomechanical testing and FEA under axial loads of 250 N, 500 N, and 750 N. We also evaluated the stress distribution and maximum stress of each fracture model using FEA. Biomechanically, under the same loads of 250 N, 500 N, or 750 N, the vertical displacement was significantly different among the three fixation groups (p ≤ 0.001). FEA data indicated that the maximum displacement from group A to C was 3.58 mm, 3.23 mm, and 2.78 mm at 750 N, respectively. The maximum stress from group A to C was 220.88 MPa, 194.63 MPa, and 156.77 MPa in implants, and 62.02 MPa, 77.71 MPa, and 54.15 MPa in bones at 750 N, respectively. The general trends at 250 N and 500 N were consistent with those at 750 N. Based on our biomechanical and FEA results, the novel plate could be a good option for treating PLTP fractures. The novel plate showed stable and reliable features, indicating its suitability for further clinical application.

CLINICAL OUTCOMES FOLLOWING GLENOHUMERAL DISLOCATION WITH GREATER TUBEROSITY FRACTURE

A fracture of the tuberosity is associated with 16% of anterior glenohumeral dislocations. Manipulation of these injuries in the emergency department is safe with less than 1% risk of fracture propagation. However, there is a risk of associated neurological injury, recurrent instability and displacement of the greater tuberosity fragment. The risks and outcomes of these complications have not previously been reported. The purpose of this study was to establish the incidence and outcome of complications associated with this pattern of injury.We reviewed 339 consecutive glenohumeral dislocations with associated greater tuberosity fractures from a prospective trauma database. Documentation and radiographs were studied and the incidence of neurovascular compromise, greater tuberosity fragment migration and intervention and recurrent instability recorded.The mean age was 61 years (range, 18–96) with a female preponderance (140:199 male:female). At presentation 24% (n=78) patients had a nerve injury, with axillary nerve being most common (n=43, 55%). Of those patients with nerve injuries 15 (19%) did not resolve. Greater tuberosity displacement &gt;5mm was observed in 36% (n=123) of patients with 40 undergoing acute surgery, the remainder did not due to comorbidities or patient choice. Persistent displacement after reduction accounted for 60 cases, later displacement within 6 weeks occurred in 63 patients. Recurrent instability occurred in 4 (1%) patients. Patient reported outcomes were poor with average EQ5D being 0.73, QDASH score of 16 and Oxford Shoulder Score of 41.Anterior glenohumeral dislocation with associated greater tuberosity fracture is common with poor long term patient reported outcomes. Our results demonstrate there is a high rate of neurological deficits at presentation with the majority resolving spontaneously. Recurrent instability is rare. Late tuberosity fragment displacement occurs in 18% of patients and regular follow-up for 6 weeks is recommended to detect this.

Management of Lingual Cortex Fracture of Mandible Using Lingual Arch Bar: A Finite Element Analysis of Reduction with a Pilot Clinical Trial.

Fractures of lingual cortex are frequently left untreated leading to poor resolution of patient's symptoms and function. Positioning an implant on same side of fracture would provide better reduction. The study aims at improving stability offered by Erich arch bar placed on lingual surface, by Finite element analysis (FEA) along with a pilot clinical trial. Two FEA models were generated from CT scan of an individual having lingual cortex fracture: control model with labial arch bar and study model with lingual arch bar. Parameters assessed: Stress distribution (Mpa) along lines of osteosynthesis; Separation of fracture fragments (mm) across fracture line. Associated, was a clinical trial of 5 patients, managed by placing lingual arch bar. Feasibility of arch bar, post-operative pain, radiographic inter-fragmentary gap and complications were assessed clinically. Lingual positioning of arch bar demonstrated less displacement (mm) of fracture fragments compared to labial placement (0.123 vs. 0.677) upon application of masticatory load. Insignificant lingual splay and lesser degree of stress distribution (Mpa) was observed (83.1 vs. 99.3) favoring placement of arch bar on lingual side. Clinical trial correlated with outcomes of FEA, resulting in improvement of patient's symptoms. FEA and supporting clinical trial provided an effective method of reduction for lingual cortical fracture.

Outcomes and complications after treatment for anteromedial facet fracture of the coronoid process: A systematic review

BackgroundFracture of the anteromedial facet (AMF) of the coronoid process is associated with varus posteromedial rotatory instability (VPMRI). However, there is still controversy regarding the optimal treatment for AMF fracture. The purpose of this study is to report on a systematic review of the outcomes and complications after treatment for AMF fracture. MethodsThis study was conducted using electronic databases, PubMed, EMBASE and Scopus. Studies reporting outcome scores and complications were included. Studies that did not utilize O'Driscoll classification for AMF fractures were excluded. Through conduct of a thorough review of included studies, definite VPMRI were identified and cases involving other injury mechanisms were excluded. ResultsFifteen articles reporting on 246 patients were included. According to O'Driscoll classification, 6.2% of cases were anteromedial subtype I, 73.7% were subtype II, and 20.1% were subtype III. Two-hundred sixteen patients (87.8%) were treated surgically and 30 patients (12.2%) were treated conservatively. Lateral collateral ligament (LCL) injuries were 76.2% (157/206) and medial collateral ligament injuries were 16.9% (33/195). Among 216 cases who underwent surgical treatment, depending on the fragment size, displacement, and instability, coronoid fixation was performed in 189 cases and LCL repair alone was performed in 27 cases. The mean final Mayo Elbow Performance Score was 92.1 and the Broberg & Morrey score was 89.5. The overall complication and reoperation rates were 17.7% (41/232) and 12.9% (26/202). ConclusionsBoth surgical and conservative treatment for AMF fractures resulted in satisfactory final clinical outcomes. However, high complication and reoperation rates were observed.

Novel screw-cable integrated system(SCIS) for minimally invasive treatment of patella transverse fractures: a finite element analysis

BackgroundThe most recommended method for treating transverse patella fractures is modified tension band wiring (MTBW). However, the optimal instrument for use with MTBW is still undetermined. Hence, we aimed to design a novel screw-cable integrated system (SCIS) and compare its biomechanical characteristics with Kirschner-wire, SCIS, and Cable-Pin systems in treating transverse patellar fracture.MethodsA finite-element (FE) model of transverse patella fracture was created. The fracture model was fixed with either K-wire, SCIS, or Cable-pin. Different tension force loading (400 N and 800 N), direction(0° and 45°), and screw or K-wire depth(5 mm and 10 mm) were set. The maximum displacement of the fragment and maximum gap opening were measured by using FE analysis.ResultsCompared with the K-wire and Cable-pin system, SCIS increased the stability of the fractured patella by reducing fragment displacement and gap opening. Under 400 N loading in the direction 45°, SCIS with screw placing at 5-mm depth reduced the maximum fragment displacement (0.43 mm) by 49.62% and 26%, respectively, compared with the K-wire (0.22 mm) and Cable-pin (0. 22 mm) group. Meanwhile, the gap opening in SCIS (0.05 mm) was reduced by 83% and 59.8% (0.05 to 0.18) compared with the K-wire (0.30 mm) and Cable-pin (0.18 mm) group.ConclusionSCIS demonstrated improved biomechanical stability for treating transverse patellar fractures compared to MTBW with Kirschner wire and the Cable-Pin system. Finite element analysis showed SCIS substantially reduced fracture fragment displacement and gap opening under various loading conditions.

Outcomes of Odontoid Process Fracture Surgery

Background. Odontoid fractures are found in two age groups. In younger patients, they occur following traffic accidents, falls from a height and during sports. In older patients with poor bone quality, they are usually caused by falls from one’s own height. Most fractures are stable and do not require surgical treatment. Unstable, severely displaced fractures with neurological deficits require surgical treatment. The aim of the study was to evaluate the surgical and functional outcomes of treatment of odontoid fractures with a cannulated screw. Materials and methods. The study enrolled 20 patients that underwent surgery in the years 2020-2022. The patients were divided into two groups: below 60 (group A) and over 60 years of age (group B). Patients were assessed at one day pre-op, one day post-op, 6 weeks following surgery and 3 months following surgery. Imaging studies were performed to assess the angulation and degree of displacement of bone fragments. After the fracture was surgically fixed with a cannulated screw, bone union and the stability of fracture fixation were assessed. Preoperative and postoperative pain intensity as per a VAS, functional status assessed with the NDI questionnaire, quality of life (EQ-VAS) and neurological status (ASIA scale) were compared. Results. Good functional and surgical results were obtained in both groups of patients. Performance and quality of life improved, while pain intensity decreased in all patients. In 3 patients with post-traumatic paresis, the dysfunctions gradually subsided. No general medical or perioperative complications were observed. Bone union of the fracture was achieved in 40% of patients in group B and in 80% in group A. Achieving union did not determine the functional status of patients. On functional radiographs, all places of fixation were stable. Conclusions. 1. Odontoid fracture fixation with a single cannulated screw is a safe method of treatment. It provided a high union rate and good stability of the fracture. 2. Fracture non-union was noted more often in the group of older patients, but it did not negatively impact quality of life and performance.

Comparison between Novel Anatomical Locking Guide Plate and Conventional Locking Plate for Acetabular Fractures: A Finite Element Analysis.

The treatment of complex acetabular fractures remains a complicated clinical challenge. Our self-designed novel anatomical locking guide plate (NALGP) has previously shown promising potential in T-shaped acetabular fractures (TAF), but a direct comparison with conventional fixations is yet to be made. The TAF model was established based on a volunteer's computer tomography data and then fixed with double column locking plates (DLP), a posterior column locking plate with anterior column screws (LPACS), and our NALGP. Forces of 200 N, 400 N, and 600 N were then loaded on the model vertically downward, respectively. The stress distribution and peaks and maximum displacements at three sites were assessed. We found that the stress area of all three plates was mainly concentrated around the fracture line, while only the matching screws of the NALGP showed no obvious stress concentration points. In addition, the NALGP and DLP showed significantly less fracture fragment displacement than the LPACS at the three main fracture sites. The NALGP was found to have less displacement than DLP at the posterior column and ischiopubic branch sites, especially under the higher loading forces of 400 N and 600 N. The fixation stability of the NALGP for TAF was similar to that of DLP but better than that of LPACS. Moreover, the NALGP and its matching screws have a more reasonable stress distribution under different loads of force and the same strength as the LPACS.

Finite element analysis of five internal fixation modes in treatment of Day type Ⅱcrescent fracture dislocation of pelvis

To compare the biomechanical differences among the five internal fixation modes in treatment of Day type Ⅱ crescent fracture dislocation of pelvis (CFDP), and find an internal fixation mode which was the most consistent with mechanical principles. Based on the pelvic CT data of a healthy adult male volunteer, a Day type Ⅱ CFDP finite element model was established by using Mimics 17.0, ANSYS 12.0-ICEM, Abaqus 2020, and SolidWorks 2012 softwares. After verifying the validity of the finite element model by comparing the anatomical parameters with the three-dimensional reconstruction model and the mechanical validity verification, the fracture and dislocated joint of models were fixed with S 1 sacroiliac screw combined with 1 LC-Ⅱ screw (S 1+LC-Ⅱ group), S 1 sacroiliac screw combined with 2 LC-Ⅱ screws (S 1+2LC-Ⅱ group), S 1 sacroiliac screw combined with 2 posterior iliac screws (S 1+2PIS group), S 1 and S 2 sacroiliac screws combined with 1 LC-Ⅱ screw (S 1+S 2+LC-Ⅱ group), S 2-alar-iliac (S 2AI) screw combined with 1 LC-Ⅱ screw (S 2AI+LC-Ⅱ group), respectively. After each internal fixation model was loaded with a force of 600 N in the standing position, the maximum displacement of the crescent fracture fragments, the maximum stress of the internal fixation (the maximum stress of the screw at the ilium fracture and the maximum stress of the screw at the sacroiliac joint), sacroiliac joint displacement, and bone stress distribution around internal fixation were observed in 5 groups. The finite element model in this study has been verified to be effective. After loading 600 N stress, there was a certain displacement of the crescent fracture of pelvis in each internal fixation model, among which the S 1+LC-Ⅱ group was the largest, the S 1+2LC-Ⅱ group and the S 1+2PIS group were the smallest. The maximum stress of the internal fixation mainly concentrated at the sacroiliac joint and the fracture line of crescent fracture. The maximum stress of the screw at the sacroiliac joint was the largest in the S 1+LC-Ⅱ group and the smallest in the S 2AI+LC-Ⅱ group. The maximum stress of the screw at the ilium fracture was the largest in the S 1+2PIS group and the smallest in the S 1+2LC-Ⅱ group. The displacement of the sacroiliac joint was the largest in the S 1+LC-Ⅱ group and the smallest in the S 1+S 2+LC-Ⅱ group. In each internal fixation model, the maximum stress around the sacroiliac screws concentrated on the contact surface between the screw and the cortical bone, the maximum stress around the screws at the iliac bone concentrated on the cancellous bone of the fracture line, and the maximum stress around the S 2AI screw concentrated on the cancellous bone on the iliac side. The maximum bone stress around the screws at the sacroiliac joint was the largest in the S 1+LC-Ⅱ group and the smallest in the S 2AI+LC-Ⅱ group. The maximum bone stress around the screws at the ilium was the largest in the S 1+2PIS group and the smallest in the S 1+LC-Ⅱ group. For the treatment of Day type Ⅱ CFDP, it is recommended to choose S 1 sacroiliac screw combined with 1 LC-Ⅱ screw for internal fixation, which can achieve a firm fixation effect without increasing the number of screws.

Anterior column acetabulum fracture fixation with a screw-augmented acetabular cup—a biomechanical feasibility study

BackroundThe beneficial effects of unrestricted postoperative full weight bearing for elderly patients suffering hip fractures have been demonstrated. However, there is still existing disagreement regarding acetabular fractures.The aim of this biomechanical study was to evaluate the initial load bearing capabilities of different fixation constructs of anterior column fractures (ACFs) in osteoporotic bone. MethodsArtificial pelvises with ACFs were assigned to three groups (n = 8) and fixed with either a 7.3 mm partially threaded antegrade cannulated screw (group AASS), an anteriorly placed 3.5 mm plate (group AAPF), or a press-fit acetabular cup with screw augmentation (group AACF). All specimens underwent ramped loading from 20 N preload to 200 N at a rate of 18 N/s, followed by progressively increasing cyclic testing at 2 Hz until failure performed at a rate of 0.05 N/cycle. Relative displacements of the bone fragments were monitored by motion tracking. FindingsInitial stiffness (N/mm) was 118.5 ± 34.3 in group AASS, 100.4 ± 57.5 in group AAPF, and 92.9 ± 44.0 in group AACF, with no significant differences between the groups, p = 0.544. Cycles to failure were significantly higher in groups AACF (8364 ± 2243) and AAPF (7827 ± 2881) compared to group AASS (4440 ± 2063), p ≤ 0.041. InterpretationFrom a biomechanical perspective, the minimally invasive cup fixation with screw augmentation demonstrated comparable stability to plate osteosynthesis of ACFs in osteoporotic bone. The results of the present study do not allow to conclusively answer whether immediate full weight bearing following cup fixation shall be allowed. Given its similar performance to plate osteosynthesis, this remains rather an utopic wish and a more conservative approach deems more reasonable.