The Impact of Complex Loadings on the Structure of the L2-L3 Intervertebral Disc in a Sheep Spine Cadaver Model: A Biomechanical and Histological Evaluation.

Background The human vertebral column generates movements under versatile, dynamic loads. Understanding how the spine reacts to these movements and loads is crucial for developing new spine implants and surgical treatments for intervertebral disc injuries. Mechanically uni-axial compression models have been extensively studied. However, the spine's daily loading is not limited to compression, so it is crucial to measure its behavior in all movements (flexion-extension, rotation, and axial compression). Methods This study utilized L1-L5 segments from 19 healthy adult sheep spines. The L2-L3 disc of the first spine underwent only histological evaluation without biomechanical testing to define basic histological parameters. The remaining 18 were divided into three groups of six and subjected to biomechanical tests. Different mechanisms for three groups of spinal segments were prepared, and tests were performed on Shimadzu AG-IS 10 KN (Universal Drawing Press, Kyoto, Japan). An axial load (800 N) was applied to the first group, an axial load with 15 degrees of flexion to the second group, and an axial load with 10 degrees of rotation plus 15 degrees of flexion to the third group. A biomechanical evaluation of the maximum elongation amounts (MEAs) was performed and compared between the groups. Then, the L2-L3 discs were removed from the sheep spines, and a histological examination of the discs was conducted using Hematoxylin-Eosin (HE), Alcian Blue (AB), and Masson's Trichrome (MT) staining. Results The mean MEA ± Standard Deviation (Range) was 1.39 ± 0.38 (0.91-1.94) for Group 1, 2.02 ± 0.75 (0.91-3.01) for Group 2, and 2.47 ± 1.09 (0.64-3.9) for Group 3. Biomechanically, although MEAs increased from Group 1 to Group 3 (meaning that the mean MEAs increased as the number of types of applied force increased), there was no statistically significant difference between the groups regarding the MEAs (P = 0.092). Histologically, no significant differences were observed between all groups after HE staining. In all groups, hypercellularity, edema in the connective tissue, separation between tissue layers, delamination, and signs of swelling and necrosis in the cells were observed similarly. For the AB staining, there was a decrease in the glycosaminoglycan (GAG) structure in the tissue samples compared to the control tissue, but no significant differences were observed between the groups. However, it was observed that the stratification in Group 3 was slightly more deteriorated than in the other groups. For the MT staining, collagen structure deterioration was observed in all groups. It was observed that the amount of collagen was significantly reduced compared to the control tissue. Conclusion As a result, when the axial load is applied biomechanically, there is more displacement of the vertebral discs in Group 3 with multidimensional movements. Furthermore, histological studies revealed deterioration between tissue layers when exposed to complex movements, and the degradation of stratification in group 3 compared to other loading combinations in groups 2 and 3 may indicate the role of complex loads in the formation of disc herniation.

Mean S1 inlet and outlet view angles are not safe for all individuals according to three-dimensional tomographic measurements.

Although there are many studies evaluating optimal inlet and outlet angles required for the correct placement of S1 iliosacral screws, there is no study evaluating reliability and feasibility of these angles for all individuals on three-dimensional (3D) anatomical models. A total of 100 women and 100 men were selected randomly. A vertical line was created according to long axis of the tomography device on which patient was lying in supine position. The automatized best-fit planes were created on superior and inferior endplates, anterior cortex including notch region and posterior cortex of first sacral vertebrae using 3D imaging software to measure mean inlet and outlet angles. We observed no statistically significant difference between gender groups in terms of inlet and outlet angles. Mean inlet view is obtained for anterior cortex of S1 in 22.5 ± 9.5° and for posterior cortex in 46.5 ± 9.3°. Mean fluoroscopic view angle of S1 for superior outlet is 40.3 ± 7.6 and for inferior outlet is 46.9 ± 8.8. Mean anterior and posterior S1 inlet view angles do not accurately visualize anterior cortex of 74 (37%) and posterior cortex of 66 (33%) individuals. Mean superior and inferior S1 outlet view angles do not accurately visualize superior endplate of 74 (37%) and inferior endplate of 56 (28%) individuals. Due to individual alterations of spatial position of sacrum, mean inlet and outlet view angles of S1 are not sufficient to visualize the iliosacral screws under fluoroscopy in many individuals.

TT-TG distance decreases after open wedge distal femoral varization osteotomy in patients with genu valgum & patellar instability. A pilot 3D computed tomography simulation study.

BACKGROUND: Genu valgum is considered to be a risk factor for patellar instability. Correction of valgus alone or combined with a tibial tuberosity medialization has been described. However, changes occurring in the tibial tuberosity-trochlear groove (TT-TG) distance after a lateral distal femoral opening wedge osteotomy (LDF-OWO) are not known. PURPOSE: This study aimed to define changes in TT-TG distance with increasing amounts of valgus correction after LDF-OWO. METHODS: Three-Dimensional Computed Tomography (3D-CT) scans of six patients (two females and four males) aged between 19 and 35 years with genu valgum and patellar instability were analyzed. 3D models of femoral, tibial, and patellar bones were created with the advanced segment option of Mimics 21® software. An oblique lateral opening wedge osteotomy of the distal femur was simulated in 2-degree increments up to 12 degrees of varus opening. Change in TT-TG distance was measured in mm on 3D models of the knee. RESULTS: Compared to baseline without osteotomy, the TT-TG distance decreased significantly (p < 0.05) for all corrections from 2 to 12 degrees in 2° steps. The TT-TG distance decreased by an average of 1.7 mm for every 2 degrees of varus opening. CONCLUSION: Lateral opening wedge distal femoral osteotomy causes a decrease in TT-TG distance. The surgeon should be aware of the magnitude of this change (1.7 mm decrease for every 2° increment of valgus opening).

Incidence and Factors Associated With Pulmonary Embolism After Upper Extremity Trauma: A Tertiary Hospital Experience in Turkey.

Introduction Venous thromboembolism (VTE), particularly pulmonary embolism (PE), is the third highest cause of death in trauma patients who survive beyond the first day. Musculoskeletal surgery is associated with several complications, some of which may be life-threatening, including deep vein thrombosis (DVT) and PE. Objective This research aims to describe risk variables for VTE after upper extremity (UE) fracture at a single institution and estimate the incidence of PE following UE fracture. Methods The writers accessed the database via their respective universities using the International Standard Classification (ICD) codes. The medical files of patients aged 18 and older who sought treatment at our emergency department for an injury to their UE and also sought treatment at the orthopedics and traumatology clinic between the years 2013 and 2021 were manually scanned. The patients who applied to the Chest Diseases Clinic within 30 days after the trauma and were diagnosed with PE in the ICD code scan were included in the study. Results UE trauma was the cause of admission to the emergency department for 3,265 patients, and 21 of those patients (0.64%) were found to have PE. Fifteen of the patients were male, and six were female. The median age was 59 years (IQR 17). There were no deaths associated with PE. One of the patients had a scaphoid fracture, seven patients had a humerus fracture, five patients had a distal radius fracture, two patients had an acromioclavicular joint injury, one patient had a shoulder dislocation, one patient had a finger fracture, four patients had wrist crush injury. Three patients had diabetes mellitus. Five patients were active smokers. JAK-2 gene V617F mutation was detected in one patient. One patient was diagnosed with prostate cancer, and one had gastric cancer. One patient had a central venous catheter. Two patients were being treated for hypothyroidism. Two patients had hypertension. Conclusion According to the findings of our research, the probability of developing PE in the days following of an injury to the UE was found to be 0.64%. Patients with UE injuries who are active smokers and who also have diabetes, hypertension, hypothyroidism, cancer, coagulation disorder (JAK2 gene V617F mutation), or a central venous catheter may benefit from anticoagulant prophylaxis. This is because these patients are at a higher risk of developing dangerous blood clots.

Patients with Achilles Tendon Rupture Are Prone to Develop Ventricular Arrhythmia.

BACKGROUND AND OBJECTIVES: This study aimed to examine the ventricular repolarization (VR) disturbances of patients operated on for acute spontaneous Achilles tendon ruptures (ATRs), by comparing them with a healthy individual control group. MATERIALS AND METHODS: Between June 2014 and July 2020, a total of 29 patients (28 males, 1 female; mean age: 40 ± 9.78 years; range, 21-66 years) who presented to the emergency department within the first three weeks of injury, and were diagnosed with acute spontaneous ATRs and treated with an open Krackow suture technique, were retrospectively analyzed. Fifty-two healthy individuals (47 males, 5 females; mean age: 39 ± 11.45 years; range, 21-66 years) were recruited as a control group from the cardiology outpatient clinic. Clinical data (demographic features and laboratory parameters (serum glucose, creatinine, hemoglobin, white blood cell count, and lipid profile)) and electrocardiograms (ECGs) were collected from medical records. ECGs were evaluated for heart rate and VR parameters of QRS width, QTc interval, cQTd interval, Tp-e interval, and Tp-e/QT ratio. The clinical data and these ECG parameters were compared between groups. RESULTS: There was no statistically significant difference between groups, regarding clinical data (all p < 0.05). Among ECG parameters, heart rate, QRS width, QTc interval, and cQTd interval were similar between groups (all p < 0.05). There were two important statistically significant findings of this research: The mean Tp-e interval was longer (ATR group: 72.4 ± 24.7, control group: 58.8 ± 14.5, p: 0.01), and the Tp-e/QT ratio was higher (ATR group: 0.2 ± 0.1, control group: 0.16 ± 0.4, p: 0.027) in the ATR group. CONCLUSIONS: According to the ventricular repolarization disturbances found in this study, patients with ATR may be at a higher risk of ventricular arrhythmia than healthy people. As a result, ATR patients should be assessed for ventricular arrhythmia risk by an expert cardiologist.

Determination of the Optimal Syndesmosis Fixation Angle Using the Mortise View of the Ankle Joint.

BACKGROUND: Syndesmosis is an important soft-tissue component supporting ankle stability. It is commonly injured along with ankle fractures. Accurate reduction and fixation of syndesmosis is essential to obtain better functional results. Therefore, we aimed to find a practical method using the mortise view of the ankle to determine the optimal syndesmosis fixation angle intraoperatively. METHODS: We randomly selected 200 adults (100 women and 100 men) aged 18 to 60 years. Three-dimensional anatomical models of the tibia and fibula were created. We created a best-fit plane on the articular surface of the medial malleolus and a 90° vertical plane to the medial malleolus plane. We determined two splines on the cortical borders of the tibia and fibula distant from the most superior point of the ankle joint in horizontal view. We created two spheres that fit to the predefined splines. The optimal syndesmosis fixation angle was determined measuring the angle between the line connecting the center points of the spheres and the 90° vertical plane to the medial malleolus plane. RESULTS: We observed no statistically significant difference in optimal syndesmosis fixation angles between sex groups. The participant mean ± SD age was 47.1 ± 10.5 years. The optimal syndesmosis fixation angle in the mortise view was found to be 21° ± 4.3°. CONCLUSIONS: We determined the optimal syndesmosis fixation angle to be 21° ± 4.3° using the mortise view of the ankle. The surgeon could evaluate the whole articular surface of the ankle joint with the medial and lateral syndesmotic spaces in mortise view accurately, and at the same position syndesmosis fixation could be performed at a mean ± SD angle of 21° ± 4.3°.

Is three-point index reliable in the follow-up of the distal radius metaphys fractures in the pediatric age group?

Three-point index (TPI), which can be used in the follow-up of conservative treatment, is an important indicator and reveals objective results about the fracture redisplacement. The hypothesis of the current study was that an initial TPI value of 0.6-0.8 may also be dangerous as it has the potential to exceed over 0.8 before a sufficient consolidation occurs and a prompt revision of the cast may prevent an upcoming displacement. This prospective controlled study 84 patients between 4 and 16 years of age, with radius distal metaphyseal fractures with more than 30% displacement or more than 15° initial angulation, were included. All of the patients in the groups had no redisplacement at 5-7 days and had TPI between 0.6 and 0.8. The patients who had cast replacement and adjusted TPI below 0.6 were included Group 1. The patients who had no cast replacement were included in Group 2. Redisplacement was observed in 8 of 38 (21%) patients in the Group 1 and in 27 of 46 (58%) patients in the Group 2 ( P value 0.001). Redisplacement with cast revision was 2.8 times less ( P < 0.005). The first reduction quality, fracture obliquity, renewed TPI values were found to be statistically significant for the prediction of redisplacement ( P < 0.005). We recommend that the follow-up of the TPI is an important predictive factor in the conservative treatment of pediatric metaphyseal radius fractures. TPI may be renewed for protection of the fracture reduction when calculated in the gray zone which is 0.6-0.08.

The Effect of Lateralization of a Pelvic Brim Plate on the Fixation of an Anterior Column Fracture: A Biomechanical Analysis.

Objectives Anterior column fractures can be seen as either isolated or accompanied by many types of complex acetabulum fractures. The aim of this study was to biomechanically compare the stability of a standard pelvic brim plate with a more laterally located suprapectineal plate, which is more commonly used in minimally invasive application, on an intermediate height anterior column fracture model under dynamic and static loading. Materials and methods Right side, adult, foam cortical shell artificial hemipelvis models were used (Sawbones, Pacific Research Laboratories, Vashon, WA, USA). Twenty-four (24) pieces of foam cortical shell artificial hemipelvis models were separated into three groups (M, L, and control). In group "M," a suprapectineal plate was placed medially just adjacent to the pelvic brim. In group "L," a laterally located suprapectineal plate was placed 2 cm lateral of the pelvic brim at its most proximal point. Then, dynamic load testing of 1000 cycles between 50 N and 500 N force and a static load test of 1.2 kN at 2 mm/minute were applied. Dynamic and static tests were conducted on an axial compression device. Displacements were measured after dynamic and static loading conditions. Results In the dynamic loading test at the AL point (superior intersection of the fracture line with the acetabular roof), the median displacement was significantly higher in group L than in group M (0.12 (IQR: 0.058-0.8125) mm and 0.04 (IQR: 0.03-0.065) mm (p = 0.02)). There was no other statistically significant difference in the displacement amounts in both dynamic and static loading conditions at other measurement points. The comparison of the stiffness of the M and L groups showed no statistically significant results, while the control group was significantly more rigid than both the M and L groups (p = 0.04 for both). None of the artificial hemipelvis models was found to be fractured at the end of the test. Conclusion Suprapectineal plates, placed on either the medial or lateral aspect of the pelvic brim, may be used for the fixation of anterior column-type fractures to provide rigid fixation and stability. As plate location did not impact stiffness and stability, the results suggest that surgeons have flexibility in determining the fixation based on accessibility, fracture pattern, and surgeon experience.

Is Proximal Tibia Sufficient for Accurate Measurement of Tibial Slope Angles on Three-dimensional Tomography-based Anatomical Models?

BACKGROUND: Tibial slope measurements performed using only the proximal part of tibia ignore the native tibial anatomical axis. Our first aim is to measure the native medial, lateral and total tibial slope angles of gender groups using the whole tibial anatomical axis on computerized tomography-based three-dimensional anatomical models. The second aim is to determine the correlation between proximal and whole tibial anatomical axis for measurement of medial, lateral, and total tibial slope angles. METHODS: We randomly selected 100 females and 100 males between 18-60 years of age. Three-dimensional anatomical models of right and left tibia were created. The gender-specific differences of medial, lateral, and total tibial slope angles according to proximal and whole tibial anatomical axis were measured. Correlation coefficients (r) of medial, lateral, and total tibial slope angles measured with proximal and whole tibial anatomical axis were calculated. RESULTS: The mean age was 47.1 years. A statistically significant difference was observed between female (7.1 ± 3) and male (8.2 ± 2.5) groups in terms of mean lateral tibial slope angles according to the whole tibial anatomical axis (p=0.008). A strong correlation between proximal and whole tibial anatomical axis for all tibial slope angle measurements was detected. CONCLUSION: The method we determined for 3D measurement of medial, lateral and total tibial slope angles using proximal tibial anatomical axis has a strong correlation with slope angles measured in accordance with the whole tibial anatomical axis. Our 3D tibial slope angle measurement method on the proximal tibia has high reliability and could be used in the daily practice.

Two-Stage Surgery for the Malleolar Fracture-Dislocation With Severe Soft Tissue Injuries Does Not Affect the Functional Results.

Soft tissue injuries associated with malleolar fracture-dislocations may increase postoperative rates of wound complication. Ankle-spanning frame plays a fundamental role in the local damage control orthopedics while gaining time for definitive surgery. The objective of this study was to evaluate the effect of a 2-stage surgery for the unstable malleolar fracture-dislocations with severe soft tissue injuries compared to a 1-stage surgery in terms of the American Orthopaedic Foot and Ankle Society (AOFAS) hindfoot-ankle and Olerud-Molander ankle scores (OMAS). We analyzed 45 patients who met our study criteria. The patients were divided into 2 groups according to staged surgeries. Demographic data of patients, comorbidities, alcohol and tobacco use, Tscherne soft tissue injury scores, the AOFAS hindfoot-ankle and OMAS, postoperative complications, total hospitalization times, waiting time between stages, and waiting time from admission to surgery times were investigated. There was a statistically significant difference between the groups in terms of the mean total hospitalization times (p = .007), waiting time from admission to surgery (p < .001), gender (p = .005), and Tscherne soft tissue injury scores (p < .001). The mean AOFAS hindfoot-ankle and OMAS of the groups did not differ statistically at a minimum of 12 months of the follow-up period (p = .094 and p = .126, respectively). A 2-stage surgery can be performed safely in the carefully selected patients with the unstable malleolar fracture-dislocations with Tscherne grades 2 and 3 soft tissue injuries, and this surgery does not affect the postoperative AOFAS hindfoot-ankle and OMAS statistically compared to a 1-stage surgery at a minimum of 12 months of the follow-up period.