Triple-Mechanism Enhanced Flexible SiO2 Nanofiber Composite Hydrogel with High Stiffness and Toughness for Cartilaginous Ligaments.

Hydrogels are widely used in tissue engineering, soft robotics and wearable electronics. However, it is difficult to achieve both the required toughness and stiffness, which severely hampers their application as load-bearing materials. This study presents a strategy to develop a hard and tough composite hydrogel. Herein, flexible SiO2 nanofibers (SNF) are dispersed homogeneously in a polyvinyl alcohol (PVA) matrix using the synergistic effect of freeze-drying and annealing through the phase separation, the modulation of macromolecular chain movement and the promotion of macromolecular crystallization. When the stress is applied, the strong molecular interaction between PVA and SNF effectively disperses the load damage to the substrate. Freeze-dried and annealed-flexible SiO2 nanofibers/polyvinyl alcohol (FDA-SNF/PVA) reaches a preferred balance between enhanced stiffness (13.71 ± 0.28 MPa) and toughness (9.9 ± 0.4 MJ m-3). Besides, FDA-SNF/PVA hydrogel has a high tensile strength of 7.84 ± 0.10 MPa, super elasticity (no plastic deformation under 100 cycles of stretching), fast deformation recovery ability and excellent mechanical properties that are superior to the other tough PVA hydrogels, providing an effective way to optimize the mechanical properties of hydrogels for potential applications in artificial tendons and ligaments.

Primary anterior cruciate ligament repair-morphological and quantitative assessment by 7-T MRI and clinical outcome after 1.5 years.

OBJECTIVES: The purpose of this study was to assess morphological and quantitative changes of the anterior cruciate ligament (ACL) and cartilage after ACL repair. METHODS: 7T MRI of the knee was acquired in 31 patients 1.5 years after ACL repair and in 13 controls. Proton density-weighted images with fat saturation (PD-fs) were acquired to assess ACL width, signal intensity, elongation, and fraying. T2/T2* mapping was performed for assessment of ACL and cartilage. Segmentation of the ACL, femoral, and tibial cartilage was carried out at 12 ROIs. The outcome evaluation consisted of the Lysholm Knee Score and International Knee Documentation Committee (IKDC) subjective score and clinical examination. RESULTS: ACL showed a normal signal intensity in 96.8% and an increased width in 76.5% after repair. Fraying occurred in 22.6% without having an impact on the clinical outcome (Lysholm score: 90.39 ± 9.75, p = 0.76 compared to controls). T2 analysis of the ACL revealed no difference between patients and controls (p = 0.74). Compared to controls, assessment of the femoral and tibial cartilage showed a significant increase of T2* times in all ROIs, except at the posterolateral femur. Patients presented a good outcome in clinical examination with a Lysholm score of 87.19 ± 14.89 and IKDC of 80.23 ± 16.84. CONCLUSION: T2 mapping results suggest that the tissue composition of the ACL after repair is similar to that of a native ACL after surgery, whereas the ACL exhibits an increased width. Fraying of the ACL can occur without having any impact on functional outcomes. T2* analysis revealed early degradation at the cartilage. CLINICAL RELEVANCE STATEMENT: MRI represents a noninvasive diagnostic tool for the morphological and compositional assessment of the anterior cruciate ligament after repair, whereas knowledge about post-surgical alterations is crucial for adequate imaging interpretation. KEY POINTS: • There has been renewed interest in repairing the anterior cruciate ligament with a proximally torn ligament. • T2 times of the anterior cruciate ligament do not differ between anterior cruciate ligament repair patients and controls. • T2 mapping may serve as a surrogate for the evaluation of the anterior cruciate ligament after repair.

ESR essentials: MRI of the knee-practice recommendations by ESSR.

Many studies and systematic reviews have been published about MRI of the knee and its structures, discussing detailed anatomy, imaging findings, and correlations between imaging and clinical findings. This paper includes evidence-based recommendations for a general radiologist regarding choice of imaging sequences and reporting basic MRI examinations of the knee. We recommend using clinicians' terminology when it is applicable to the imaging findings, for example, when reporting meniscal, ligament and tendon, or cartilage pathology. The intent is to standardise reporting language and to make reports less equivocal. The aim of the paper is to improve the usefulness of the MRI report by understanding the strengths and limitations of the MRI exam with regard to clinical correlation. We hope the implementation of these recommendations into radiological practice will increase diagnostic accuracy and consistency by avoiding pitfalls and reducing overcalling of pathology on MRI of the knee. CLINICAL RELEVANCE STATEMENT: The recommendations presented here are meant to aid general radiologists in planning and assessing studies to evaluate acute and chronic knee findings by advocating the use of unequivocal terminology and discussing the strengths and limitations of MRI examination of the knee. KEY POINTS: • On MRI, the knee should be examined and assessed in three orthogonal imaging planes. • The basic general protocol must yield T2-weighted fluid-sensitive and T1-weighted images. • The radiological assessment should include evaluation of ligamentous structures, cartilage, bony structures and bone marrow, soft tissues, bursae, alignment, and incidental findings.

The female urethral closure mechanism during physical stress.

The closure of the urethra under the condition of stress is the result of a reflex contraction of the urethral rhabdosphincter and pelvic floor muscles. This is likely induced by activity of the abdominal muscles due to a sudden increase in abdominal pressure. This reflex contraction with an increase of urethral pressure occurs a few milliseconds before an increase in intraabdominal pressure. The urethral pressure increase during stress is only possible with fixation of the urethra by the pubourethral ligaments (PUL), facilitating urethral kinking. The highest and most important increase in pressure and resistance occurs in the distal urethra due to this kinking of the urethra.

Prospective diagnostic test accuracy of transvaginal ultrasound posterior approach for uterosacral ligament and torus uterinus deep endometriosis.

OBJECTIVE: To determine the diagnostic test accuracy of transvaginal ultrasound (TVS) using a standardized technique for the diagnosis of deep endometriosis (DE) of the uterosacral ligaments (USLs) and adjacent torus uterinus (TU). METHODS: This was a prospective diagnostic test accuracy study conducted at the McMaster University Medical Center Tertiary Endometriosis Clinic, Hamilton, ON, Canada. Consecutive participants were enrolled if they successfully underwent TVS and surgery by our team from 10 August 2020 to 31 October 2021. The index test was TVS using a standardized posterior approach performed and interpreted by an expert sonologist. The reference standard included direct surgical visualization on laparoscopy by the same person who performed and interpreted the ultrasound scans. Accuracy, sensitivity, specificity, positive and negative predictive values (PPV and NPV) and positive and negative likelihood ratios were calculated for the TVS posterior approach for each location using the reference standard. RESULTS: There were 54 consecutive participants included upon completion of laparoscopy and histological assessment. The prevalence of DE for the left USL, right USL and TU was 42.6%, 22.2% and 14.8%, respectively. Based on surgical visualization as the reference standard, TVS demonstrated an accuracy of 92.6% (95% CI, 82.1-97.9%), sensitivity of 82.6% (95% CI, 61.2-95.1%), specificity of 100% (95% CI, 88.8-100%), PPV of 100% and NPV of 88.6% (95% CI, 76.1-95.0%) for diagnosing DE in the left USL. For DE of the right USL, TVS demonstrated an accuracy of 94.4% (95% CI, 84.6-98.8%), sensitivity of 75.0% (95% CI, 42.8-94.5%), specificity of 100% (95% CI, 91.6-100%), PPV of 100% and NPV of 93.3% (95% CI, 84.0-97.4%). For DE of the TU, TVS demonstrated an accuracy of 100% (95% CI, 93.4-100%), sensitivity of 100% (95% CI, 63.1-100%), specificity of 100% (95% CI, 92.3-100%), PPV of 100% and NPV of 100%. CONCLUSIONS: We observed high diagnostic test accuracy of the evaluated standardized TVS technique for assessing DE of the USLs and TU. Further studies evaluating this technique should be performed, particularly with less experienced observers, before considering this technique as the standard approach. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Asymmetric loading strategies during squats following anterior cruciate ligament reconstruction: A longitudinal investigation with curve analyses throughout and after rehabilitation.

Investigations of kinetic asymmetries during bilateral squats following anterior cruciate ligament reconstruction (ACLR) are limited to mainly cross-sectional studies and discrete value data extracted at specific knee angles. We assessed loading asymmetries during squats longitudinally throughout rehabilitation using curve analysis and compared patient-reported outcome measures (PROMs) between those with and without asymmetry. Bodyweight squats were performed by 24 individuals (13 females) post-ACLR on three occasions: (1) Early 2.9 (1.1) months; (2) Mid 8.8 (3.1) months; (3) at Return to Sport (RTS) 13.1 (3.6) months; and 29 asymptomatic controls (22 females) once. Time-normalized between-leg asymmetry curves of sagittal plane hip, knee, and ankle moments and vertical ground reaction forces were compared using functional data analysis methods. Individual asymmetrical loading for ACLR was classified when exceeding the 95% confidence interval of controls during ≥50% of the squat. At Early, ACLR had greater asymmetry than controls for knee (15%-100% eccentric phase; 0%-100% concentric) and ankle flexion moments (56%-65% concentric). At Mid, ACLR had greater asymmetry for knee (41%-72% eccentric) and ankle flexion moments (56%-69% concentric). No between-group differences were found at RTS. From Early to RTS, ACLR reduced asymmetry for hip (21%-46% eccentric), knee (27%-58% concentric), and ankle flexion moments (21%-57% eccentric). At Early, 11/24 underloaded their ACLR knee and 1 overloaded compared with controls. At RTS, 4 underloaded and 6 overloaded. No differences in PROMs were found based on loading asymmetry. Beyond the early phase of rehabilitation from ACLR, individual-level analyses are required to reveal differing loading strategies during bilateral squats.

A Histomorphometric and Computational Investigation of the Stabilizing Role of Pectinate Ligaments in the Aqueous Outflow Pathway.

Murine models are commonly used to study glaucoma, the leading cause of irreversible blindness. Glaucoma is associated with elevated intra-ocular pressure (IOP), which is regulated by the tissues of the aqueous outflow pathway. In particular, pectinate ligaments (PLs) connect the iris and trabecular meshwork (TM) at the anterior chamber angle, with an unknown role in maintenance of the biomechanical stability of the aqueous outflow pathway, thus motivating this study. We conducted histomorphometric analysis and optical coherence tomography-based finite element (FE) modeling on three cohorts of C57BL/6 mice: "young" (2-6 months), "middle-aged" (11-16 months), and "elderly" (25-32 months). We evaluated the age-specific morphology of the outflow pathway tissues. Further, because of the known pressure-dependent Schlemm's canal (SC) narrowing, we assessed the dependence of the SC lumen area on varying IOPs in age-specific FE models over a physiological range of TM/PL stiffness values. We found age-dependent changes in morphology of outflow tissues; notably, the PLs were more developed in older mice compared to younger ones. In addition, FE modeling demonstrated that murine SC patency is highly dependent on the presence of PLs and that increased IOP caused SC collapse only with sufficiently low TM/PL stiffness values. Moreover, the elderly model showed more susceptibility to SC collapse compared to the younger models. In conclusion, our study elucidated the previously unexplored role of PLs in the aqueous outflow pathway, indicating their function in supporting TM and SC under elevated IOP.

Comparison of the Kinematics and Laxity of Total Knee Arthroplasty Bearing Designs Stabilized With Specimen-Specific Virtual Ligaments on a Joint Motion Simulator.

A variety of total knee arthroplasty (TKA) designs offer increased congruency bearing options, primarily to compensate for a loss of posterior cruciate ligament (PCL) function. However, their efficacy in providing sufficient stability under different circumstances requires further investigation. The preclinical testing of prosthesis components on joint motion simulators is useful for quantifying how design changes affect joint stability. However, this type of testing may not be clinically relevant because surrounding ligaments are either ignored or greatly simplified. This study aimed to assess the kinematics and stability of TKA joints during various motions using condylar-stabilized (CS) bearings without a PCL versus cruciate-retaining (CR) bearings with an intact PCL. TKA prosthetic components were tested on a joint motion simulator while being stabilized with five different sets of specimen-specific virtual ligament envelopes. In comparison to CR knees, CS knees without a PCL exhibited a greater amount of posterior tibial displacement laxity, with a mean increase of 2.7±2.1 mm (p = 0.03). Additionally, significant differences were observed in the anterior-posterior kinematics of the knee joint during activities of daily living (ADL) between the two designs. These results were consistent with previous cadaveric investigations, which indicated that CS knees without a PCL are less resistant to posterior tibial displacement than CR knees with one. This study employing virtual ligaments confirms previous findings that the raised anterior lip of some CS bearings may not completely compensate for the absence of the PCL; however, as both studies used reduced joint contact forces, the contributions of this design feature may be attenuated.

On growth and scoliosis.

PURPOSE: To describe the physiology of spinal growth in patients with adolescent idiopathic scoliosis (AIS). METHODS: Narrative review of the literature with a focus on mechanisms of growth. RESULTS: In his landmark publication On Growth and Form, D'Arcy Thompson wrote that the anatomy of an organism reflects the forces it is subjected to. This means that mechanical forces underlie the shape of tissues, organs and organisms, whether healthy or diseased. AIS is called idiopathic because the underlying cause of the deformation is unknown, although many factors are  associated. Eventually, however, any deformity is due to mechanical forces. It has long been shown that the typical curvature and rotation of the scoliotic spine could result from vertebrae and intervertebral discs growing faster than the ligaments attached to them. This raises the question why in AIS the ligaments do not keep up with the speed of spinal growth. The spine of an AIS patient deviates from healthy spines in various ways. Growth is later but faster, resulting in higher vertebrae and intervertebral discs. Vertebral bone density is lower, which suggests  less spinal compression. This also preserves the notochordal cells and the swelling pressure in the nucleus pulposus. Less spinal compression is due to limited muscular activity, and low muscle mass indeed underlies the lower body mass index (BMI) in AIS patients. Thus, AIS spines grow faster because there is less spinal compression that counteracts the force of growth (Hueter-Volkmann Law). Ligaments consist of collagen fibres that grow by tension, fibrillar sliding and the remodelling of cross-links. Growth and remodelling are enhanced by dynamic loading and by hormones like estrogen. However, they are opposed by static loading. CONCLUSION: Increased spinal elongation and reduced ligamental growth result in differential strain and a vicious circle of scoliotic deformation. Recognising the physical and biological cues that contribute to differential growth  allows earlier diagnosis of AIS and prevention in children at risk.

Presurgical perspective and postsurgical evaluation of acromioclavicular joint instability.

Acromioclavicular joint (ACJ) dislocations are a common cause of pain in patients of any age. Athletes who participate in contact sports, such as hockey, football, rugby, and soccer, are particularly susceptible to such injuries. The ACJ has an important role in the function of the upper limb, and its complexity of movement makes it susceptible to acute injuries and chronic dysfunction with debilitating effects that must be treated appropriately and promptly to preserve function. Recently, ACJ has received increasing attention due to the development of new surgical techniques for the restoration of normal function and stability. There is some agreement about the treatment of ACJ dislocations, but controversy remains about the treatment of Rockwood grade III dislocations, and a new approach to these injuries is suggested by ISAKOS. Overall, the paper summarizes new concepts in the anatomy of the ACJ and reviews the utility of imaging methods in ACJ dislocations as well as their treatment and complications.

3D isotropic MRI of ankle: review of literature with comparison to 2D MRI.

The ankle joint has complex anatomy with different tissue structures and is commonly involved in traumatic injuries. Magnetic resonance imaging (MRI) is the primary imaging modality used to assess the soft tissue structures around the ankle joint including the ligaments, tendons, and articular cartilage. Two-dimensional (2D) fast spin echo/turbo spin echo (FSE/TSE) sequences are routinely used for ankle joint imaging. While the 2D sequences provide a good signal-to-noise ratio (SNR) and contrast-to-noise ratio (CNR) with high spatial resolution, there are some limitations to their use owing to the thick slices, interslice gaps leading to partial volume effects, limited fluid contrast, and the need to acquire separate images in different orthogonal planes. The 3D MR imaging can overcome these limitations and recent advances have led to technical improvements that enable its widespread clinical use in acceptable time periods. The volume imaging renders the advantage of reconstructing into thin continuous slices with isotropic voxels enabling multiplanar reconstructions that helps in visualizing complex anatomy of the structure of interest throughout their course with improved sharpness, definition of anatomic variants, and fluid conspicuity of lesions and injuries. Recent advances have also reduced the acquisition time of the 3D datasets making it more efficient than 2D sequences. This article reviews the recent technical developments in the domain 3D MRI, compares imaging with 3D versus 2D sequences, and demonstrates the use-case scenarios with interesting cases, and benefits of 3D MRI in evaluating various ankle joint components and their lesions.

The deltoid ligament is constantly formed by four fascicles reaching the navicular, spring ligament complex, calcaneus and talus.

PURPOSE: The medial collateral ligament of the ankle, or deltoid ligament, can be injured in up to 40% of patients who sustain an ankle inversion sprain. Reporting injuries of the deltoid ligament is not easy due to confusion in the current anatomical descriptions, with up to 16 fascicles described, with variable frequencies. The purpose of this study was to clarify the anatomy of the deltoid ligament. METHODS: Thirty-two fresh-frozen ankle specimens were used for this study. Careful dissection was undergone until full visualization of the deltoid ligament was achieved and measurements taken. RESULTS: The deltoid ligament was found to have four constant fascicles in two layers. The superficial layer consists of the tibionavicular, tibiospring and tibiocalcaneal fascicles, while the deep layer consists of the tibiotalar fascicle. Measurements of these fascicles are given in detail. The tibiotalar fascicle and the anterior part of the tibionavicular fascicle were found to be intra-articular structures. CONCLUSION: The deltoid ligament has a constant number of fascicles divided into a superficial and a deep layer. This clarification of the anatomy and terminology of the deltoid ligament and its fascicles will help clinical view, diagnosis and (interdoctor)communication and treatment. The ligamentous fibres of the deep layer, as well as the anterior fibres of the superficial layer (tibionavicular fascicle) are intra-articular, which could negatively impact its healing capacity, explaining chronicity of these types of injuries. LEVEL OF EVIDENCE: Not applicable (cadaveric study).

Acute clinical evaluation for the diagnosis of lateral ankle ligament injuries is useful: A comparison between the acute and delayed settings.

PURPOSE: To determine the diagnostic value of seven injury history variables, nine clinical tests (including the combination thereof) and overall clinical suspicion for complete discontinuity of the lateral ankle ligaments in the acute (0-2 days post-injury) and delayed setting (5-8 days post-injury). METHODS: All acute ankle injuries in adult athletes (≥18 years) presenting up to 2 days post-injury were assessed for eligibility. Athletes were excluded if imaging studies demonstrated a frank fracture or 3 T MRI could not be acquired within 10 days post-injury. Using standardized history variables and clinical tests, acute clinical evaluation was performed within 2 days post-injury. Delayed clinical evaluation was performed 5-8 days post-injury. Overall, clinical suspicion was recorded after clinical evaluation. MRI was used as the reference standard. RESULTS: Between February 2018 and February 2020, a total of 117 acute ankle injuries were screened for eligibility, of which 43 were included in this study. Complete discontinuity of lateral ankle ligaments was observed in 23 (53%) acute ankle injuries. In the acute setting, lateral swelling had 100% (95% confidence interval [CI]: 82-100) sensitivity, haematoma had 85% (95% CI: 61-96) specificity and the anterior drawer test had 100% (95% CI: 77-100) specificity. In the delayed setting, sensitivity for the presence of haematoma improved from 43% (95% CI: 24-65) to 91% (95% CI: 70-98; p < 0.01) and the sensitivity of the anterior drawer test improved from 21% (95% CI: 7-46) to 61% (95% CI: 39-80; p = 0.02). Clinical suspicion had a positive likelihood ratio (LR) of 4.35 (95% CI: 0.55-34.17) in the acute setting and a positive LR of 6.09 (95% CI: 1.57-23.60) in the delayed setting. CONCLUSIONS: In the acute setting, clinical evaluation can exclude complete discontinuity (e.g., absent lateral swelling) and identify athletes with a high probability of complete discontinuity (e.g., positive anterior drawer test) of the lateral ankle ligaments. In the delayed setting, the sensitivity of common clinical findings increases resulting in an improved diagnostic accuracy. In clinical practice, this study underlines the importance of meticulous clinical evaluation in the acute setting. LEVEL OF EVIDENCE: Level III.

Comparative clinical outcomes and radiological images of clavicle hook plate versus Scorpion Plate® for unstable distal clavicle fractures.

BACKGROUND: Although various surgical methods are available for unstable distal clavicle fractures, consensus remains lacking on the optimal technique. Therefore, the present retrospective study aimed to compare the clavicle hook plate and Scorpion Plate® in terms of clinical outcomes and radiological findings for unstable distal clavicle fractures. METHODS: Fifty-seven patients with unstable distal clavicle fractures who underwent treatment using a clavicle hook plate (Group H; 28 patients) or Scorpion Plate® (Group S; 29 patients) were included in the present study. No patients received additional augmentation and all were followed-up for >1 year (mean follow-up, 28 months). Clinical outcomes were operation time, bleeding volume, complications, range of motion (ROM) at 6 months after surgery and final follow-up, and clinical scores (Constant-Murley score and University of California, Los Angeles (UCLA) shoulder score). Radiological outcomes assessed were coracoclavicular distance (CCD), difference in CCD between affected and non-affected sides (ΔCCD), and acromioclavicular subluxation ratio (%ACS) from plain X-rays. The χ2 test and Mann-Whitney U test were used to compare each outcome. RESULTS: Complications were seen in 3 shoulders (10.7%) in Group H. ROM was significantly worse in Group H at 6 months postoperatively, but no significant differences between groups were evident at final follow-up. Moreover, no significant differences in clinical outcomes were seen between groups. In terms of radiological results, Group H showed greater improvement in CCD and ΔCCD than Group S. Further, %ACS was significantly worse in Group S. CONCLUSIONS: The clavicle hook plate allows reconstruction of a more anatomical position than the Scorpion Plate®, but carries a greater risk of complications. Conversely, the Scorpion Plate® has a low risk of complications, but acromioclavicular subluxation remains. However, no significant differences in ROM or clinical outcomes were apparent at final follow-up.

Anatomical study of the sacrotuberous ligament and the hamstring muscles: A histomorphological analysis.

The sacrotuberous ligament (STL) and the hamstrings are important structures that are mutually connected and influenced by the pelvis. However, the anatomical connectivity and histological characteristics of these structures remain unclear. The present study aimed to comprehensively investigate the relationship between the STL and the proximal hamstrings through histological analysis. Sixteen specimens were obtained from eight fresh cadavers (mean age at death, 73.4 years). Verhoeff Van Gieson, Masson's trichrome, and immunohistochemical staining were used to analyze the connectivity between the STL and the hamstrings and to verify the ratios of collagen and elastic fibers. Dense connective tissue that overlapped tightly between the STL and hamstrings was observed. The relative ratios of collagen and elastic fibers between the STL and hamstrings characteristically identified regional differences. The ratio of elastic fibers to collagen in the biceps femoris (BF) was ~38.6 ± 4.7%, and the lowest ratio was 5.9 ± 2.6% observed in the semimembranosus (SM). In the case of the BF, contractibility is well-regulated due to a high content of elastic fibers; however, the muscular structure of the BF is relatively fragile due to the low content of collagen. In the SM, collagen content is higher than that in the STL. This ratio of elastic fibers in the collagen analysis could provide crucial information for understanding the differences in hamstring contractility and maintaining the morphology of these structures.

A histology guide for performing human cadaveric studies: SQIP 2024 what to look for with light microscopy.

Histological observation under light microscopy has long been used in human cadaveric studies. However, it can distort the interpretations of findings if not used appropriately; there is no guide for its proper use. The aim of this article is to revisit and discuss the correct use of histology in human cadaveric studies, following discussions with experts in multiple fields of medicine, and to create the first guide for such usage. We reached a consensus with the experts, agreeing that when this principle (structure, quantification, interaction, position: SQIP) is applied to histological observations, the findings will be interpreted correctly. Appropriate use of this recommendation can make human cadaveric studies more accurate and informative. This is the first histology guide for human cadaveric studies.

Allografts use in orthopedic surgery: trend change over the past 11 years from a regional tissue bank.

Allografts are the second most transplanted tissue in medicine after blood and are now increasingly used for both primary and revision surgery. Allografts have the advantages of lower donor site morbidity, availability of multiple grafts, and shorter operative time. The Banks represents the bridge between Donor and Recipient and guarantees the quality and safety of the distributed allografts Given the increasing interest in these tissues, a retrospective analysis of data collected from the Regional Musculoskeletal Tissue Bank registry over an 11-year period (2009-2019) was conducted. The statistical analyses used were the Shapiro-Wilk normality test and a Poisson regression model. From January 2009 to December 2019, a total of 14,199 musculoskeletal tissues stored in the Regional Musculoskeletal Tissue Bank were provided for surgical allograft procedures. In 2009, the number of allografts performed was 925; this figure has steadily increased to 1599 in 2019. Epiphyses were taken as the reference tissue with an almost constant trend over the period, while a significant increase was denoted for extensor mechanism allograft, ligaments, tendons and long bone corticals (p < 0.001), processed bone tissues had no change in trend (p = 0.841). There was also a gradual decrease in the rate of microbiological positivity, as determined by bacteriological and serological tests performed on the collected tissues. This phenomenon is due to improved sampling techniques and the training of a dedicated team. Thus, we have seen how the use of allografts in orthopedic surgery has increased over the past 11 years, uniformly in terms of tissue type, except for the noticeable increase in ligamentous tissue.

Ex vivo evaluation of the soft tissue components of the equine stifle using 3 Tesla magnetic resonance imaging under flexion, extension, and loading.

High-field MRI of the equine stifle provides high-resolution information about soft tissues that is useful in the diagnosis of stifle lameness. The aim of this prospective anatomic study was to describe the appearance, position, size, and shape of the equine femorotibial ligaments, meniscal ligaments, and menisci using 3 Tesla MRI under extended, extended-loaded, and flexed conditions. Additionally, histologic examination of the collateral and cruciate ligaments (CLs) of a single stifle was performed to compare with MRI images. In extension, mild variations in MRI signal intensity were apparent in the CLs, and the cranial had two distinct longitudinal regions indicating two ligament bundles. Flexion had minor effects on CL signal intensity and altered the tibial angles of attachment. Histology indicated that both CLs were comprised of two fiber bundles. The collateral ligaments were the same low-signal intensity. The medial collateral ligament had a smaller cross-sectional area than the lateral, and flexion increased the length of the medial collateral ligament and the cross-sectional area of the lateral. Low loads in extension did not affect the MRI appearance of stifle soft tissues. Flexion of the stifle impacted cruciate ligament insertion angles and the size and shape of collateral ligaments. This study provides support for the use of MRI to understand the anatomy and function of stifle ligaments.

Description of the lateral fibulotalocalcaneal ligament in fetal specimens and its potential clinical implications.

PURPOSE: The increase in ankle sprains in children is a reflection of the greater inclusion of this population in sports. This places the calcaneofibular (CFL) and the anterior talofibular (ATFL) ligaments in focus for study. In adults, the presence of arcuate fibers extending between these two ligaments suggests the existence of a new anatomical and functional complex called the lateral fibulotalocalcaneal ligament of the ankle (LFTCL), which can be associated with the persistence of instability of the talocrural joint in ankle sprains. This study aimed to verify the presence of arciform fibers between the CFL and ATFL in human fetuses and to study the topography of the lateral ankle region. METHODS: Forty matched fetal ankles aged between 28 and 38 weeks, fixed in 4% formalin, were macroscopically, chemically and mesoscopically dissected and analyzed in stereoscope. RESULTS: The ATFL was characterized as a capsular ligament consisting of two fascicles (proximal and distal). The CFL was characterized as an extracapsular ligament. The LFTCL complex was verified in all specimens, characterized by the arcuate fibers between the ATFL and the CFL. CONCLUSION: Such results suggest that this functional unit is congenital and that it should be taken into consideration in the treatment of persistent ankle instabilities in the pediatric population.

Correlation of sex hormone levels with orthodontic tooth movement in the maxilla: a prospective cohort study.

BACKGROUND: Sex hormones secreted during the menstrual cycle and the application of orthodontic forces to teeth can affect the metabolism of periodontal ligaments. This study aimed to determine whether there are any differences in orthodontic tooth displacement during the menstrual cycle and when using hormonal contraceptives and whether the amount of female sex hormones influences the efficiency of tooth displacement. METHODS: A total of 120 women aged between 20 and 30 years with Angle Class II requiring transpalatal arch (TPA) to derotate teeth 16 and 26 were included in this study. The participants were divided into two groups: group A, which included women with regular menstruation, and control group B, which included women taking monophasic combined oral contraceptives. Group A was divided into subgroups according to the moment of TPA activation: menstruation (A1), ovulation phase (A2), and luteal phase (A3) (examination I). On intraoral scans, measurement points were marked on the proximal mesial cusps of teeth 16 and 26, and the intermolar distance (M1) was determined. The change in the position of the measurement points 6 weeks after activation (examination II) made it possible to determine the derotating extent of teeth 16 (O16) and 26 (O26) and the widening of the intermolar distance (M2-M1). In examinations I and II, tooth mobility in the alveoli was assessed using Periotest based on the periotest values (PTV) PTV1 and PTV2, respectively. RESULTS: A significant difference in all parameters was observed among groups A1, A2, and A3 (P < 0.001). Group A3 showed the highest values of parameters O16, O26, and M2-M1, and group A2 showed the lowest values, which did not differ from the control group (P = 0.64). PTV2 and PTV1 were the highest in group A3 and the lowest in groups A1 and B. Intergroup differences were statistically significant (P < 0.001). CONCLUSIONS: With the quantification of changes in tooth mobility in the alveoli during the menstrual cycle in women undergoing orthodontic treatment, it was possible to determine that female sex hormones affect the effectiveness of orthodontic treatment, and the optimal moment for TPA activation is the luteal phase of the menstrual cycle.