Ligament Ruptures in Ankle Fractures-Was Lauge-Hansen Right?

The contribution of Lauge-Hansen to the understanding and treatment of ankle fractures cannot be underestimated, an unquestionable merit being the analysis of the ligamentous component of these injuries that are considered as equivalent to the respective malleolar fractures. In numerous clinical and biomechanical studies, the lateral ankle ligaments are ruptured either together with or instead of the syndesmotic ligaments, as predicted by the Lauge-Hansen stages. A ligament-based view on malleolar fractures may deepen the understanding of the mechanism of injury and lead to a stability-based evaluation and treatment of the 4 osteoligamentous pillars (malleoli) at the ankle.

Torsion of the Falciform Ligament Diagnosed by Imaging Tests - Case Report of an Unusual Disease.

The falciform ligament is a peritoneal double layer that anatomically divides the right and left hepatic lobes. Abnormality of the falciform ligament is rare - less than 20 cases of torsion of the falciform ligament have been reported to date in adults. The pathophysiology of these entities is similar to intra-abdominal focal fat infarction. The clinical of the patient with torsion of the falciform ligament is abdominal pain of sudden onset and focal location. Laboratory tests can lead to diagnostic confusion with cholecystitis. Ultrasonography is usually the initial evaluation test, but the gold standard diagnosis is computed tomography. We report the case of a 30-year-old female patient reporting sudden abdominal pain that radiates to the dorsal region associated with nausea and vomiting diagnosed with torsion of the falciform ligament with ultrasonography and confirmed with computed tomography. She was treated conservatively without the need for surgical treatment, being discharged after one week hospitalization.

Development of Multibundle Virtual Ligaments to Simulate Knee Mechanics After Total Knee Arthroplasty.

Preclinical evaluation of total knee arthroplasty (TKA) components is essential to understanding their mechanical behavior and developing strategies for improving joint stability. While preclinical testing of TKA components has been useful in quantifying their effectiveness, such testing can be criticized for lacking clinical relevance, as the important contributions of surrounding soft tissues are either neglected or greatly simplified. The purpose of our study was to develop and determine if subject-specific virtual ligaments reproduce a similar behavior as native ligaments surrounding TKA joints. Six TKA knees were mounted to a motion simulator. Each was subjected to tests of anterior-posterior (AP), internal-external (IE), and varus-valgus (VV) laxity. The forces transmitted through major ligaments were measured using a sequential resection technique. By tuning the measured ligament forces and elongations to a generic nonlinear elastic ligament model, virtual ligaments were designed and used to simulate the soft tissue envelope around isolated TKA components. The average root-mean-square error (RMSE) between the laxity results of TKA joints with native versus virtual ligaments was 3.5 ± 1.8 mm during AP translation, 7.5 ± 4.2 deg during IE rotations, and 2.0 ± 1.2 deg during VV rotations. Interclass correlation coefficients (ICCs) indicated a good level of reliability for AP and IE laxity (0.85 and 0.84). To conclude, the advancement of virtual ligament envelopes as a more realistic representation of soft tissue constraint around TKA joints is a valuable approach for obtaining clinically relevant kinematics when testing TKA components on joint motion simulators.

The Influence of Fiber Orientation of the Conus Elasticus in Vocal Fold Modeling.

While the conus elasticus is generally considered a part of continuation of the vocal ligament, histological studies have revealed different fiber orientations that fibers are primarily aligned in the superior-inferior direction in the conus elasticus and in the anterior-posterior direction in the vocal ligament. In this work, two continuum vocal fold models are constructed with two different fiber orientations in the conus elasticus: the superior-inferior direction and the anterior-posterior direction. Flow-structure interaction simulations are conducted at different subglottal pressures to investigate the effects of fiber orientation in the conus elasticus on vocal fold vibrations, aerodynamic and acoustic measures of voice production. The results reveal that including the realistic fiber orientation (superior-inferior) in the conus elasticus yields smaller stiffness and larger deflection in the coronal plane at the junction of the conus elasticus and ligament and subsequently leads to a greater vibration amplitude and larger mucosal wave amplitude of the vocal fold. The smaller coronal-plane stiffness also causes a larger peak flow rate and higher skewing quotient. Furthermore, the voice generated by the vocal fold model with a realistic conus elasticus has a lower fundamental frequency, smaller first harmonic amplitude, and smaller spectral slope.

A Novel Technique for Lateral Ankle Ligament Reconstruction with Total Ankle Total Talus Replacement: A Case Report.

CASE: A 65-year-old man with severe left talar avascular necrosis, arthritis, and chronic lateral ankle instability underwent total ankle total talus replacement (TATTR) with lateral ligament reconstruction. Tibial component placement was performed using preoperative computed tomography navigation and patient-specific guides. A custom, total talus replacement to mate with the fixed-bearing tibial component was implanted. Last, a modified Brostrom procedure was performed to restore lateral ankle stability. The patient has performed well through 1 year with improved pain-free function. CONCLUSION: This case report details a novel technique for performing a modified Brostrom procedure in conjunction with TATTR to restore lateral ankle stability.

Elastin is responsible for the rigidity of the ligament under shear and rotational stress: a mathematical simulation study.

BACKGROUND: An accurate understanding of the mechanical response of ligaments is important for preventing their damage and rupture. To date, ligament mechanical responses are being primarily evaluated using simulations. However, many mathematical simulations construct models of uniform fibre bundles or sheets using merely collagen fibres and ignore the mechanical properties of other components such as elastin and crosslinkers. Here, we evaluated the effect of elastin-specific mechanical properties and content on the mechanical response of ligaments to stress using a simple mathematical model. METHODS: Based on multiphoton microscopic images of porcine knee collateral ligaments, we constructed a simple mathematical simulation model that individually includes the mechanical properties of collagen fibres and elastin (fibre model) and compared with another model that considers the ligament as a single sheet (sheet model). We also evaluated the mechanical response of the fibre model as a function of the elastin content, from 0 to 33.5%. Both ends of the ligament were fixed to a bone, and tensile, shear, and rotational stresses were applied to one of the bones to evaluate the magnitude and distribution of the stress applied to the collagen and elastin at each load. RESULTS: Uniform stress was applied to the entire ligament in the sheet model, whereas in the fibre model, strong stress was applied at the junction between collagen fibres and elastin. Even in the same fibre model, as the elastin content increased from 0 to 14.4%, the maximum stress and displacement applied to the collagen fibres during shear stress decreased by 65% and 89%, respectively. The slope of the stress-strain relationship at 14.4% elastin was 6.5 times greater under shear stress than that of the model with 0% elastin. A positive correlation was found between the stress required to rotate the bones at both ends of the ligament at the same angle and elastin content. CONCLUSIONS: The fibre model, which includes the mechanical properties of elastin, can provide a more precise evaluation of the stress distribution and mechanical response. Elastin is responsible for ligament rigidity during shear and rotational stress.

Finite element analysis of conductive hearing loss caused by fixation and detachment of ligament and tendon in the middle ear.

BACKGROUND AND OBJECTIVE: The fixation of ligament and tendon of the middle ear often occurs after chronic otitis media surgery. However, there are relatively few studies on the effect of ligament and tendon on sound transmission in the human middle ear. Here, the finite element model and lumped parameter model are used to study the effect of ligament and tendon fixation and detachment on sound transmission in human ear. METHODS: In this paper, the finite element model including the external auditory canal, middle ear and simplified inner ear is used to calculate and compare the middle ear frequency response of the normal and tympanosclerosis under pure tone stimulation. In addition, the lumped parametric model is taken into account to illustrate the effect of ligament and tendon stiffness on the human ear transmission system. RESULTS: The results indicate that the motion of the tympanic membrane and stapes is reduced by ligament and tendon fixation. Although ligament and tendon detachment have a limited effect in the piston-motion direction, the stability of motion in the plane perpendicular to the piston-motion direction is significantly reduced. Most significantly, the ligament and tendon fixation cause a hearing effect of about 18 dB, which is greater in the plane perpendicular to the piston-motion direction after ligament and tendon detachment than in the piston-motion direction. CONCLUSIONS: In this study, the calculation accuracy of the lumped parameter and the finite element model is studied, and the effect of ligament and tendon on hearing loss is further explored through the finite element model with high calculation accuracy, which is helpful to understand the role of ligament and tendon in the sound transmission mechanism of the human middle ear. The study of ligament and tendon on conductive hearing loss provides a reference for clinical treatment of tympanosclerosis.

Applications of Finite Element Modeling in Biomechanical Analysis of Foot Arch Deformation: A Scoping Review.

Excessive foot arch deformation is associated with plantar tissue overload and ligamentous injury pathologies. Finite element (FE) analysis, as an effective tool for modeling and simulation, has been utilized clinically for providing insights into arch biomechanics. This systematic scoping review aimed to summarize the current state of computational modeling techniques utilized in arch biomechanics from 2000 onwards and outline the main challenges confronting the further development of accurate models in clinical conditions. English-language searches of the electronic databases were conducted in the Web of Science, PubMed, and Scopus until July 2022. Articles that investigated arch deformation mechanisms by FE modeling were included. The methodological quality was assessed utilizing the Methodological Quality Assessment of Subject-Specific Finite Element Analysis Used in Computational Orthopedics (MQSSFE). Seventeen articles were identified in this systematic scoping review, mostly focusing on constructing models for specific pathological conditions, such as progressive collapsing foot deformity, valgus foot, and posterior tibial tendon dysfunction. However, given the complexity of the arch problem, geometrical simplifications regarding the balance between accurate detail and computational cost and assumptions made in defining modeling parameters (material properties and loading and boundary conditions) may bring challenges to the accuracy and generalizability of models applied to clinical settings. Overall, advances in computational modeling techniques have contributed to reliable foot deformation simulation and analysis in modern personalized medicine.

[MCL tear with intra-articular dislocation]. / MCL-Ruptur mit intraartikulärer Dislokation.

A 48-year-old male patient presented with inner skin retraction after a sports accident involving the knee. In a multi-ligament injury it must be assumed that knee dislocation has occurred. Inner skin retraction after knee distortion can result from an intra-articular dislocation of the ruptured medial collateral ligament. Prompt reduction and exclusion of concomitant neurovascular injuries is thus obligatory. After surgical reconstruction of the medial collateral ligament, instability was no longer apparent 3 months postoperatively.

The Role of the Piezo1 Mechanosensitive Channel in the Musculoskeletal System.

Since the recent discovery of the mechanosensitive Piezo1 channels, many studies have addressed the role of the channel in various physiological or even pathological processes of different organs. Although the number of studies on their effects on the musculoskeletal system is constantly increasing, we are still far from a precise understanding. In this review, the knowledge available so far regarding the musculoskeletal system is summarized, reviewing the results achieved in the field of skeletal muscles, bones, joints and cartilage, tendons and ligaments, as well as intervertebral discs.

Histological Structure of the Medial and Lateral Patellofemoral Ligaments and Implications for Reconstructive Surgery and Anterior Knee Pain.

Biomechanically, the patellofemoral joint is one of the most complex human articulations and a common source of pain for active adults and adolescents, particularly females.1-4 Patellofemoral disorders account for 20%-40% of all knee problems seen in family practice, sports medicine, and orthopedic clinics.1, 3-5.

Complete thoracoscopic S9 and/or S10 segmentectomy through a pulmonary ligament approach: a retrospective study.

BACKGROUND: The high resolution of computed tomography has found the pulmonary ligaments that consists of a double serous layer of visceral pleura, forms the intersegmental septum, and enters the lung parenchyma. This study aimed to investigate the clinical feasibility of thoracoscopic segmentectomy (TS) of the lateral basal segment (S9), posterior basal segment (S10), and both through the pulmonary ligament (PL). METHODS: Between February 2009 and November 2021, 542 patients underwent segmentectomy for malignant lung tumors at Tokyo Women's Medical University Hospital (Tokyo, Japan). This study included 51 patients. Among them, 40 underwent a complete TS of the S9, S10, or both by the PL approach (PL group), and the remaining 11 by the interlobar fissure approach (IF group). RESULTS: Patients' characteristics did not significantly differ between the two groups. In the PL group, 34 underwent video-assisted thoracoscopic surgery (VATS), and 6 underwent robot-assisted thoracoscopic surgery. In the IF group, all 11 underwent VATS. Operation duration, estimated blood loss, and postoperative complication frequency were not significantly different between these groups, but the maximum tumor diameter showed a significant difference. CONCLUSIONS: Complete TS of the S9, S10, and both through the PL is a reasonable option for tumors located in such segments. This approach is a feasible option for performing TS.

Modification of Burton and Pellegrini trapeziectomy technique: Medium-term comparative analysis / Modificación de la técnica de trapeciectomía de Burton-Pellegrini: análisis comparativo a medio término

Introduction: Ligament reconstruction and tendon interposition (LRTI) arthroplasty is the procedure of choice of most hand surgeons in the treatment of basal joint arthritis of the thumb. Progressive and natural collapse after trapeziectomy is a common problem. Description of technique: We performed LRTI with flexor carpi radialis (FCR) hemitendon technique, then proceeded to block the hemitendon plasty with a bone fragment at the base of the metacarpal. This technique allows us to maintain tension and to obtain immediate stability. Patients and methods: We conducted a single-center retrospective longitudinal observational study including 51 patients with diagnosis of symptomatic osteoarthritis of the trapeziometacarpal joint. Group A consisted of 24 thumbs treated with trapeziectomy with LRTI with FCR hemitendon using the Burton-Pellegrini technique. Group B included 27 thumbs treated using the modified technique. The postoperative height of the Scaphometacarpal (SM) space was analyzed. Clinical outcome, opposition, retroversion, patient satisfaction and surgical timing were studied. Results: The difference of the SM space, after applying correction factor, at one and six months postoperative is significantly less in the modified technique group (p=0.033 and p=0.001 respectively). The average height loss of the SM space from one to six months postoperative measurement was smaller in the study group, showing greater stability of the plasty. Conclusions: The use of a bone fragment to block the FCR plasty improves the results at one and six months postoperatively, showing a diminished height loss of the SM space, improved thumb opposition and without prolonging surgical timing in our series.(AU)

Introducción: La artroplastia con reconstrucción ligamentosa e interposición tendinosa (LRTI, en inglés) es el procedimiento de elección para tratar la rizartrosis. El colapso progresivo tras la trapeciectomía es un problema habitual. Descripción de la técnica: Realizamos una LRTI con el hemitendón del flexor carpis radialis (FCR) y, posteriormente, colocamos un fragmento óseo en la base del metacarpo para bloquear la plastia. Esta técnica nos permite obtener estabilidad inmediata y mantener la tensión. Método: Presentamos un estudio observacional longitudinal retrospectivo unicéntrico, que incluye a 51 pacientes con diagnóstico de rizartrosis sintomática. Los pacientes se dividieron en 2 grupos: grupo A, pacientes intervenidos mediante trapeciectomía con LRTI del FCR según la técnica de Burton-Pellegrini y grupo B, pacientes intervenidos mediante la técnica modificada. Se analizó la altura del espacio escafometacarpiano (EM) restante en radiografías postoperatorias. Se valoraron los resultados clínicos, como la oposición o retroversión del pulgar, satisfacción del paciente y tiempo quirúrgico. Resultados: Las diferencias en altura del espacio EM a uno y 6 meses tras la cirugía son significativamente menores con la técnica modificada (p=0,033 y p=0,001, respectivamente). La pérdida de altura media del espacio EM del primer al sexto mes tras la cirugía fue menor en el grupo B, con mayor estabilidad de la plastia. Conclusión: El uso de un fragmento óseo para bloquear la plastia del FCR mejora los resultados clínicos y radiológicos a uno y 6 meses tras la cirugía, con menor pérdida de altura del espacio EM y mejoría de la oposición del pulgar, sin aumentar el tiempo quirúrgico.(AU)

[Artículo traducido] Modificación de la técnica de trapeciectomía de Burton-Pellegrini: análisis comparativo a medio término / Modification of Burton and Pellegrini trapeziectomy technique: Medium-term comparative analysis

Introduction: Ligament reconstruction and tendon interposition (LRTI) arthroplasty is the procedure of choice of most hand surgeons in the treatment of basal joint arthritis of the thumb. Progressive and natural collapse after trapeziectomy is a common problem. Description of technique: We performed LRTI with flexor carpi radialis (FCR) hemitendon technique, then proceeded to block the hemitendon plasty with a bone fragment at the base of the metacarpal. This technique allows us to maintain tension and to obtain immediate stability. Patients and methods: We conducted a single-center retrospective longitudinal observational study including 51 patients with diagnosis of symptomatic osteoarthritis of the trapeziometacarpal joint. Group A consisted of 24 thumbs treated with trapeziectomy with LRTI with FCR hemitendon using the Burton-Pellegrini technique. Group B included 27 thumbs treated using the modified technique. The postoperative height of the Scaphometacarpal (SM) space was analyzed. Clinical outcome, opposition, retroversion, patient satisfaction and surgical timing were studied. Results: The difference of the SM space, after applying correction factor, at one and six months postoperative is significantly less in the modified technique group (p=0.033 and p=0.001 respectively). The average height loss of the SM space from one to six months postoperative measurement was smaller in the study group, showing greater stability of the plasty. Conclusions: The use of a bone fragment to block the FCR plasty improves the results at one and six months postoperatively, showing a diminished height loss of the SM space, improved thumb opposition and without prolonging surgical timing in our series.(AU)

Introducción: La artroplastia con reconstrucción ligamentosa e interposición tendinosa (LRTI, en inglés) es el procedimiento de elección para tratar la rizartrosis. El colapso progresivo tras la trapeciectomía es un problema habitual. Descripción de la técnica: Realizamos una LRTI con el hemitendón del flexor carpis radialis (FCR) y, posteriormente, colocamos un fragmento óseo en la base del metacarpo para bloquear la plastia. Esta técnica nos permite obtener estabilidad inmediata y mantener la tensión. Método: Presentamos un estudio observacional longitudinal retrospectivo unicéntrico, que incluye a 51 pacientes con diagnóstico de rizartrosis sintomática. Los pacientes se dividieron en 2 grupos: grupo A, pacientes intervenidos mediante trapeciectomía con LRTI del FCR según la técnica de Burton-Pellegrini y grupo B, pacientes intervenidos mediante la técnica modificada. Se analizó la altura del espacio escafometacarpiano (EM) restante en radiografías postoperatorias. Se valoraron los resultados clínicos, como la oposición o retroversión del pulgar, satisfacción del paciente y tiempo quirúrgico. Resultados: Las diferencias en altura del espacio EM a uno y 6 meses tras la cirugía son significativamente menores con la técnica modificada (p=0,033 y p=0,001, respectivamente). La pérdida de altura media del espacio EM del primer al sexto mes tras la cirugía fue menor en el grupo B, con mayor estabilidad de la plastia. Conclusión: El uso de un fragmento óseo para bloquear la plastia del FCR mejora los resultados clínicos y radiológicos a uno y 6 meses tras la cirugía, con menor pérdida de altura del espacio EM y mejoría de la oposición del pulgar, sin aumentar el tiempo quirúrgico.(AU)

Imaging of Anatomical Variants Around the Knee.

Several anatomical variants have been described in the knee. These variants may involve intra- and extra-articular structures, such as menisci, ligaments, plicae, bony structures, muscles, and tendons. They have a variable prevalence, are generally asymptomatic, and are usually discovered incidentally in knee magnetic resonance imaging examinations. A thorough knowledge of these findings is essential to avoid overestimating and overinvestigating normal findings. This article reviews most anatomical variants around the knee, describing how to avoid misinterpretation.

Use of LARS for soft tissue function reconstruction during tumor-type hemi-shoulder replacement achieves a good prognosis: a retrospective cohort study.

BACKGROUND: Shoulder soft tissue function reconstruction during tumor-type hemishoulder replacement is an important step to restore shoulder function. This study evaluates the functional prognosis and postoperative complications of ligament advanced reinforcement system (LARS)-assisted soft tissue functional reconstruction in tumor-type hemi-shoulder replacement. MATERIALS AND METHODS: Twenty-two patients with an average age of 37.5 ± 17.8 years diagnosed with benign invasive tumors, primary malignant bone tumors, or bone metastases were enrolled in this study. The patient's medical records (history and surgical details), histological sections, imaging files, oncological prognosis, functional prognosis, and postoperative complications were collected. The upper limb function and shoulder joint function were evaluated using the Musculoskeletal Tumor Society (MSTS) system and American Shoulder and Elbow Surgeons (ASES) scoring criteria, respectively. RESULTS: Twenty-two patients comprising 12 males and 10 females were enrolled. Overall, 9 patients had preoperative pathological fractures. The mean lesion length was 8.6 ± 3.0 cm. The local recurrence was observed in 3 cases, including 2 cases of osteosarcoma and 1 case of MGCT. A further 4 cases had pulmonary metastasis, including 2 cases with local tumor recurrence. The average postoperative MSTS score was 25.8 ± 1.7, and the score of postoperative ASES was 85.7 ± 6.0, both of which showed satisfactory functional recovery. Two cases experienced postoperative complications requiring surgical intervention, including one periprosthetic fracture and one giant cell granuloma. Prosthesis dislocation occurred in 1 case. None of the cases of periprosthetic infection or postoperative complications resulted in implant failure. CONCLUSIONS: LARS-assisted soft tissue function reconstruction in benign and malignant proximal humerus tumors after a tumor-type hemi-shoulder replacement is an effective technical improvement, which can effectively repair the integrity of the joint capsule to restore joint stability, provide a medium for soft tissue attachment to rebuild the muscular dynamic system, and eliminate residual dead space around the prosthesis, effectively improving limb function and reduce postoperative infection complications.

MR evaluation of the posteromedial corner of the knee: association of posterior horn medial meniscus tear with posterior oblique ligament and distal semi-membranosus tendon tear.

OBJECTIVE: To assess if posterior oblique ligament and distal semi-membranosus tendon tears are associated with posterior horn medial meniscus tears on MRI. METHODS: From January 1, 2018 to December 31, 2019, 56 patients who met the inclusion criteria were enrolled in this study. Of the 56 patients, 43 patients who had a posterior horn of medial meniscus tear were included in the study group. A control group of 13 individuals was formed for comparison. Two radiologists reviewed the MR images and recorded the presence and grades of posterior oblique ligament and distal semi-membranosus tendon tears. We used the independent t-test and one-way ANOVA to compare the tear grades. Interobserver agreement was analyzed using a Cohen's κ coefficient (κ value) for categorical variables. RESULTS: The mean grades for the posterior oblique ligament and distal semi-membranosus tendon tears were significantly higher in the study group (all, p < 0.001). Interobserver agreement between the two readers was substantial in assessing the grade of posterior oblique ligament tear (κ = 0.653±0.087) and almost perfect in assessing the grade of distal semi-membranosus tendon tear (κ = 0.876±0.060). CONCLUSION: Posterior oblique ligament and distal semi-membranosus tendon tears are significantly associated with posterior horn of medial meniscus tear and medial meniscus posterior root tears, and the peel-back mechanism could be related to this association. ADVANCES IN KNOWLEDGE: Presenting this paper could adjust radiologist search patterns and potentially help orthopedists with management and pre-surgical planning for the posteromedial corner injury of the knee.

Synthesis of lysinonorleucine and mass spectrometric analysis of lysinonorleucine and merodesmosine in bovine ligament and eggshell membrane.

Elastin is an important extracellular matrix protein that contributes to the elasticity of cells, tissues, and organs. Although crosslinking amino acids such as desmosine and isodesmosine have been identified in elastin, details regarding the structure remain unclear. In this study, an elastin crosslinker, lysinonorleucine, was chemically synthesized and detected in hydrolyzed bovine ligament and eggshell membrane samples utilizing tandem mass spectrometry. Merodesmosine, another crosslinker of elastin, was also measured in the same samples using the same analytical method. The resulting data should aid in the elucidating the crosslinking structure of elastin and eggshell membranes.