Estudio retrospectivo de 544 timpanoplastias con cartílago y pericondrio: resultados anatómicos y funcionales / A retrospective study of 544 tympanoplasty with cartilage and perichondrium: anatomical and functional results

Introducción: el cierre de las perforaciones timpánicas se realiza con diferentes materiales, entre ellos el cartílago y el pericondrio. En este estudio se compararon los resultados anatómicos y funcionales obtenidos con ambos materiales, y se evaluaron posibles factores asociados con los buenos resultados. Material y métodos: estudio retrospectivo en pacientes intervenidos de timpanoplastia sin mastoidectomía entre el 1 de enero de 2001 y el 31 de diciembre de 2018. Resultados: se incluyeron 544 timpanoplastias. En la mayoría se utilizó cartílago (78,5 %) y en el resto pericondrio. El cartílago se utilizó con mayor frecuencia en los menores de 18 años (p=0,001), perforaciones totales y subtotales (p=0,000) y timpanoplastias secundarias y terciarias (p=0,008). No hubo diferencias en el tiempo de seguimiento (15,68 ± 22,18 meses frente al 12,86 ± 14,9 meses, p=0,169). La tasa de éxito anatómico fue mayor en el grupo de cartílago, sin diferencias en los resultados auditivos (82 % con cartílago y 78,3 % con pericondrio). El éxito anatómico se relacionó con la técnica utilizada para la reconstrucción con cartílago, mientras que los resultados auditivos se asociaron significativamente con el estado de la mucosa del oído medio y la cadena de huesecillos en el momento de la cirugía y el éxito anatómico posquirúrgico. Conclusiones: con el cartílago se consiguieron mejores resultados anatómicos que con el pericondrio, sin diferencias a nivel funcional. Sin embargo, los resultados funcionales empeoraron si había patología a nivel del oído medio y en ausencia de restauración anatómica.

Introduction: Different materials are used to close tympanic perforations. This stu-dy aimed to compare anatomical results obtained with cartilage and perichondrium and evaluate factors associated with successful results. Material and method: Re-trospective study of patients who underwent tympanoplasty without mastoidectomy between January 1, 2001, and December 31, 2018. Demographic data, ear pathology, surgical intervention, and anatomical and functional results were collected. Results:544 tympanoplasty were included. Cartilage was the most used (78.5%). Cartilage was used more frequently in children under 18 years (p = 0.001), to reconstruct total and subtotal perforations (p = 0.000) and in secondary and tertiary tympanoplasty (p = 0.008). Follow-up time did not differ between the two groups (15.68 ± 22.18 months vs. 12.86 ± 14.9 months, p = 0.169). The anatomical success rate was higher in the cartilage group, with no significant differences in hearing outcomes (82% with cartilage and 78.3% with perichondrium). Anatomical success was related to the technique used for cartilage reconstruction (monoblock or palisade). Hearing re-sults were significantly associated with the state of middle ear mucosa at the time of surgery, the state and mobility of the ossicle chain, and post-surgical anatomical suc-cess. Conclusions: Cartilage achieved better anatomical results than perichondrium. Both materials were comparable on a functional level. However, the functional re-sults worsen if there is pathology of the middle ear (mucosa or chain of ossicles) and anatomical restoration is not achieved.

Reconstrução nasal com uso de costela em paciente com síndrome de Binder: Um relato de caso e revisão de literatura / Nasal reconstruction using ribs in a patient with Binder syndrome: A case report and literature review

Introdução: A síndrome de Binder também pode ser conhecida como displasia maxilonasal e é uma malformação congênita caracterizada por hipoplasia nasomaxilar devido a um subdesenvolvimento do esqueleto facial médio. A atual incidência ou prevalência ainda é desconhecida, mas afeta aproximadamente um recém-nascido vivo em cada 10.000 nascimentos. O diagnóstico pode ser clínico ou associado a ultrassonografia pré-natal, caracterizada por nariz achatado e convexidade anormal da maxila. O tratamento é cirúrgico para correção das anormalidades estéticas e funcionais. Relato de Caso: Paciente que recebeu diagnóstico de síndrome de Binder aos 14 anos, sem outras malformações associadas, com queixa estética e funcional nasal. A correção cirúrgica foi iniciada pela extração de um bloco da sexta cartilagem costal à esquerda, com abertura nasal na margem columelar, no padrão de uma rinoplastia aberta, e dissecados os tecidos no plano subSMAS. Após preparo da área receptora nasal, foram esculpidos bloco de cartilagem para reconstrução do dorso nasal, enxertos alares e enxerto de cartilagem septal. Houve melhora de projeção da ponta nasal e alongamento nasal. Conclusão: A rinoplastia pode ser uma cirurgia desafiadora nesses pacientes, sendo a reconstrução autóloga com o uso de cartilagem costal indicada pela literatura como a melhor opção. É necessário individualizar cada caso para programação de enxertos e reestruturação nasal, sendo fundamental também a melhora funcional desses casos.

Introduction: Binder's syndrome can also be known as maxillonasal dysplasia and it is a congenital malformation characterized by nasomaxillary hypoplasia resulting from an underdevelopment of the middle facial skeleton. The current incidence or prevalence is still unknown, but it affects approximately one child in every 10,000 births. The diagnosis can be clinical or associated with prenatal ultrasonography, characterized by a flattened nose and abnormal maxillary convexity. The treatment is surgical to correct aesthetic and functional abnormalities. Case Report: Patient diagnosed with Binder's syndrome at the age of 14, without other associated malformations, with aesthetic and functional nasal complaints. Surgical correction began with the extraction of a block of the sixth costal cartilage on the left, with a nasal opening on the columellar margin, in the pattern of an open rhinoplasty, and tissue dissection in the sub-SMAS plane. After preparing the nasal receptor area, a block of cartilage was sculpted for reconstruction of the nasal dorsum, alar grafts and septal cartilage grafts. There was an improvement in the projection of the nasal tip and nasal dorsum. Conclusion: Rhinoplasty can be a challenging surgery in these patients, and the literature indicates that the best option is autologous reconstruction with costal cartilage. It is necessary to individualize each case to schedule nasal grafts and restructuring, and functional improvement in these cases is also essential

Refixation of the Excised Acetabular Labrum can Affect the Structural Changes of Cartilage Surface in the Hip Joint / La Refijación del Labrum Acetabular Extirpado Puede Afectar los Cambios Estructurales de la Superficie del Cartílago en la Articulación Coxal

SUMMARY: Refixation of the damaged acetabular labrum is a method of surgical treatment of the hip joint that can promote the repair of joint function after injury and prevent premature osteoarthritis. We sought to determine the condition of the hip joint in rabbits 4 months after excision of the acetabular labrum and the condition of the joint after labral refixation. The articular cartilage of the femoral head and acetabulum was examined by histological methods, multipoint measurement of cartilage thickness, and the ratio between cartilage matrix and chondrocytes lacunae, and the condition of cartilage according to the OARSI grading scale was carried out. On this model, a correlation analysis was performed between the results of the OARSI grading scale and the data of linear morphometry. All these parameters made it possible to better assess changes in articular cartilage. The ratio between matrix and chondrocyte lacunae turned out to be a method that allows establishing early cartilage damage when erosion, fibrosis or deformation did not occur. We found significant differences between the condition of the cartilage after exicion of acetabular labrum and after labral refixation, which give hope to confirm that this surgical technique can delay or prevent progressive changes in the cartilage of the damaged hip joint.

La refijación del labrum acetabular dañado es un método de tratamiento quirúrgico de la articulación coxal, que puede promover la reparación de la función articular después de una lesión y prevenir la osteoartritis prematura. Intentamos determinar el estado de la articulación coxal en conejos de 4 meses después de la escisión del labrum acetabular y observar el estado de la articulación después de la refijación del labrum. El cartílago articular de la cabeza femoral y el acetábulo se examinó por métodos histológicos, se midió a través de multipunto el grosor del cartílago y se realizó la relación entre la matriz del cartílago y las lagunas de condrocitos, y se llevó a cabo la condición del cartílago según la escala de clasificación OARSI. Sobre este modelo se realizó un análisis de correlación entre los resultados de la escala de calificación OARSI y los datos de la morfometría lineal. Todos estos parámetros permitieron evaluar mejor los cambios en el cartílago articular. La relación entre la matriz y las lagunas de condrocitos resultó ser un método que permite establecer temprano el daño del cartílago cuando no se presentó erosión, fibrosis o deformación. Encontramos diferencias significativas entre la condición del cartílago después de la extirpación del labrum acetabular y después de la refijación del labrum, lo que da la esperanza de confirmar que esta técnica quirúrgica puede retrasar o prevenir cambios progresivos en el cartílago de la articulación coxal dañada.

Treatment of Chondral Lesions in the Knee / Tratamento das lesões condrais no joelho

Abstract Articular cartilage injuries are common and lead to early joint deterioration and osteoarthritis. Articular cartilage repair techniques aim at forming a cartilaginous neo-tissue to support the articular load and prevent progressive degeneration. Several techniques are available for this purpose, such as microfracture and chondrocyte transplantation. However, the procedural outcome is often fibrocartilage, which does not have the same mechanical resistance as cartilaginous tissue. Procedures with autologous osteochondral graft have a morbidity risk, and tissue availability limits their use. As such, larger lesions undergo osteochondral transplantation using fresh or frozen grafts. New techniques using minced or particulate cartilage fragments or mesenchymal stem cells are promising. This paper aims to update the procedures for treating chondral lesions of the knee.

Resumo As lesões da cartilagem articular são comuns e levam à deterioração precoce da articulação e ao desenvolvimento da osteoartrite. As técnicas de reparo da cartilagem articular visam a formação de um neo-tecido cartilaginoso capaz de suportar carga articular e evitar a progressão da degeneração. Há várias técnicas disponíveis para esse fim, como a microfratura e o transplante de condrócitos. Entretanto muitas vezes o desfecho do procedimento é a formação de fibrocartilagem, que não possui a mesma resistência mecânica do tecido cartilaginoso. Em outros procedimentos, nos quais é realizado enxerto osteocondral autólogo, há risco de morbidade associada ao procedimento, além da disponibilidade limitada de tecido. Por esse motivo, o transplante osteocondral, utilizando enxertos a fresco ou congelados tem sido utilizado para lesões de maior volume. Por fim, novas técnicas utilizando fragmentos de cartilagem picada ou particulada, assim como o uso de células tronco mesenquimais se apresentam como promissores. O objetivo desse artigo é realizar uma atualização dos procedimentos para tratamento das lesões condrais do joelho.

Child Fractures: Are We Getting More Surgical? / Fraturas na criança: Estamos ficando mais cirúrgicos?

Abstract Historically, surgeries on the immature skeleton were reserved for open or articular fractures. In recent years, the improvement in the quality and safety of anesthesia, new imaging equipment, implants designed especially for pediatric fractures, associated with the possibility of shorter hospitalization time and rapid return to social life has demonstrated a new tendency to evaluate and treat fractures in children. The purpose of this update article is to answer the following questions: (1) Are we really turning more surgical in addressing fractures in children? (2) If this is true, is this surgical conduct based on scientific evidence? In fact, in recent decades, the medical literature demonstrates articles that support better evolution of fractures in children with surgical treatment. In the upper limbs, this is very evident in the systematization of the reduction and percutaneous fixation of supracondylar fractures of the humerus and fractures of the forearm bones. In the lower limbs, the same occurs with diaphyseal fractures of the femur and tibia. However, there are gaps in the literature. The available published studies show low scientific evidence. Thus, it can be inferred that, even though the surgical approach is more present, the treatment of pediatric fractures should always be individualized and conducted according to the knowledge and experience of the professional physician, taking into account the presence of technological resources available for the care of the small patient. All possibilities, non-surgical and/or surgical, should be included, always instituting actions based on science and in agreement with the family's wishes.

Resumo Historicamente, as cirurgias no esqueleto imaturo eram reservadas às fraturas expostas ou articulares. Nos últimos anos, a melhora na qualidade e segurança das anestesias, novos equipamentos de imagem, implantes desenhados especialmente para fraturas pediátricas, associados à possibilidade de menor tempo de hospitalização e rápido retorno ao convívio social vêm demonstrando uma nova tendência de avaliar e tratar fraturas na criança. O objetivo deste artigo de atualização é responder às seguintes questões: (1) estamos realmente ficando mais cirúrgicos na abordagem das fraturas em crianças? (2) Caso isto seja verdadeiro, esta conduta cirúrgica está baseada em evidências científicas? De fato, nas últimas décadas, a literatura médica demonstra artigos que suportam melhor evolução das fraturas na criança com o tratamento cirúrgico. Nos membros superiores, isto fica muito evidente na sistematização da redução e fixação percutânea das fraturas supracondilianas do úmero e das fraturas de ossos do antebraço. Nos membros inferiores, o mesmo ocorre com fraturas diafisárias do fêmur e tíbia. No entanto, há lacunas na literatura. Os estudos publicados são geralmente com baixa evidência científica. Assim, pode-se deduzir que, mesmo sendo a abordagem cirúrgica mais presente, o tratamento de fraturas pediátricas deve ser sempre individualizado e conduzido de acordo com o conhecimento e experiência do médico profissional, levando em conta a presença de recursos tecnológicos disponíveis para o atendimento do pequeno paciente. Deve-se incluir todas as possibilidades, não cirúrgicas e/ou cirúrgicas, sempre instituindo ações baseadas na ciência e em concordância com os anseios da família.

Study of developing tracheal cartilage under light microscope

Background: Airway formation is one of the earliest events in development of respiratory system. However, maturation of airway continues well in post-natal life. The trachea has framework of incomplete ring of hyaline cartilage united by fibrous tissue and smooth muscle through which air conduction takes place. The trachea-bronchial mucosa is target for host of airborne toxic agents; bacterial and viral agents, allergens, reactive gases, aerosols, and irritant particles. This fascinates many workers for detailed study of epithelium or lining air passage. Aims and Objectives: The present study was undertaken to document normal developmental microscopic structure of tracheal cartilage in fetuses of different age group (gestational ages between 12th and 40th weeks) and to compare the difference between different age groups. Materials and Methods: Tissues from trachea of various age group fetuses were collected, processed, and stained with H and E and Masson’s trichrome. Results: Development of tracheal cartilage was observed into three trimesters. The 2nd and 3rd trimesters were further divided in the early 2nd (13th–16th weeks), mid-2nd (17th–20th weeks), late 2nd (21st–24th weeks), early 3rd (25th–28th weeks), mid-3rd (29th–32nd weeks), and late 3rd (33rd–40th weeks) phases. Conclusion: Perichondrium of cartilage had shown well-marked outer fibrous layer with increased vascularity by late 2nd to early 3rd trimester. Well-marked inner cellular layer of perichondrium was noticed by 3rd trimester, while cartilage had shown active chondrocytes by late 2nd to early 3rd trimester. At the late 3rd trimester, typical hyaline cartilage had shown chondrocytes in cell nest surrounded by territorial matrix.

Study on improvement effect mechanism of Xibining prescription on knee osteoarthritis model rats based on AMPK/mTOR signaling pathway / 中国药房

OBJECTIVE To investigate the improvement effect mechanism of Xibining prescription （XBN） on knee osteoarthritis （KOA） model rats based on AMP-activated protein kinase（AMPK）/mammalian target of rapamycin （mTOR） signaling pathway. METHODS Totally 36 rats were randomly divided into blank group， model group， XBN group （12.56 g/kg）， XBN+metformin （AMPK agonist） group （12.56 g/kg XBN+100 mg/kg metformin）， with 9 rats in each group. Except for blank group， KOA model was induced by anterior cruciate ligament transection in other groups. After modeling， each group was given relevant medicine/normal saline， XBN and normal saline intragastrically， once a day， and metformin intraperitoneally， every other day， for 4 consecutive weeks. The pathomorphological changes of cartilage tissue in rats were observed and Mankin scoring was conducted. The expression level of Aggrecan in rat cartilage， mRNA and protein expressions of platelet reactive protein disintegrin and metalloproteinase with thrombospondin motifs 4 （ADAMTS-4）， ADAMTS-5， matrix metalloproteinase 3 （MMP-3） and MMP- 13， and the phosphorylation level of AMPK and mTOR proteins were detected. RESULTS Compared with blank group， the structure of cartilage tissue in the model group was disordered， the matrix of cartilage layer was lightly stained，the tide line was distorted or interrupted， and Mankin score was significantly increased （P＜0.05）. The protein expression of Aggrecan in cartilage tissue and the phosphorylation level of AMPK protein were all decreased significantly （P＜0.05）； mRNA and protein expressions of ADAMTS-4， ADAMTS-5， MMP-3 and MMP-13 and the phosphorylation levels of mTOR protein were significantly increased in cartilage tissues （P＜0.05）. Compared with model group， the pathological morphology of cartilage was improved significantly in each administration group， and above score or indexes were reversed significantly （P＜0.05）. Compared with XBN group， the degree of cartilage lesions in rats was further alleviated in XBN+ metformin group， and the levels of above score or indicators were further improved （P＜0.05）. CONCLUSIONS XBN can ameliorate cartilage injury in KOA model rats， promote cartilage synthesis and reduce cartilage degradation， the mechanism of which may be associated with activating AMPK/mTOR signaling pathway.

Efficacy of osteochondral fragment fixation using bioabsorbable pins for Hepple Ⅱ osteochondral lesions of the talus in adolescents / 国际外科学杂志

Objective:To investigate the efficacy of osteochondral fragment fixation using bioabsorbable pins for Hepple Ⅱ osteochondral lesions of the talus (OLT) in adolescents.Methods:Retrospective case analysis was used. The clinical data and follow-up results of 13 adolescent patients (13 feet) with Hepple Ⅱ OLT were all treated with osteochondral fragment fixation using bioabsorbable pins admitted to Shanghai Sixth People′s Hospital Affiliated to Shanghai Jiao Tong University School of Medicine from January 2017 to December 2021 were retrospectively analyzed. There were 7 males and 6 females, with 13 right feet. The age was (14.85±2.23) years old, ranged from 12 to 18 years old. According to the American orthopedic foot and ankle society (AOFAS) ankle-hindfoot score, visual analogue scale (VAS) and SF-36 score before operation and at the last follow-up were used to evaluate the efficacy and function of the patients. Measurement data with normal distribution were represented as mean ± standard deviation( ± s), and the comparison between groups was conducted using the t-test; The mearsurement data with skewness distribution were expressed by M( Q1, Q3), and rank-sum test was used for inter-group comparison. Results:Thirteen adolescent patients (13 feet) with Hepple Ⅱ OLT underwent surgery successfully and were followed up for (25.54±9.95) months. All wounds healed by first intention, and no complications such as wound infection and delayed healing occurred. Preoperative AOFAS ankle-posterior foot score, VAS and SF-36 score were 58.62±3.55, 7.00 (6.50, 8.00) and 68.38±4.81, respectively. At the last follow-up, the scores were 97.38±2.73, 1.00 (0.00, 1.00), 91.15±4.28, respectively, and the results were significantly improved at the last follow-up, with the difference between the two groups statistically significant( P<0.05). Conclusion:Osteochondral fragment fixation using bioabsorbable pins which can promote cartilage repair, significantly improve symptoms, and achieve better clinical satisfaction with fewer complications, is a safe and effective surgical treatment option for Hepple Ⅱ OLT in adolescents with satisfactory short-term clinical outcomes.

Stress Relaxation Behavior of Collagen Type II- Silk Fibroin Composite Cartilage Scaffold under Different Degradation Cycles / 医用生物力学

Objective To study stress relaxation behaviors of cartilage scaffolds under different degradation cycles by using finite element analysis combined with theoretical models. Methods Based on the established degradation theoretical model, the elastic modulus of the scaffold was calculated under different degradation cycles. The finite element model of cartilage scaffolds was established and stress relaxation simulation was performed to analyze the variation of scaffold relaxation stress with time. The stress relaxation constitutive model was established to predict mechanical properties of the scaffold. Results The elastic modulus of cartilage scaffolds at 14 th, 28th, 42nd, 56th day after degradation was 32. 35, 31. 12, 29. 91, 28. 74 kPa, respectively. The upper layer for cartilage scaffolds was the largest. The overall relaxation stress of the scaffold decreased rapidly with time and then tended to be stable. At 8th week after degradation, the stress which the scaffold couldwithstand was still within the physiological load range of the cartilage. The predicted results of the stress relaxation constitutive model were in good agreement with the finite element simulation results. Conclusions The elastic modulus of the scaffold gradually decreases with the increase of degradation time. The longer the degradation period is, the less stress the scaffold can withstand. At the same degradation period, the larger the applied compressive strain, the larger the stress on the scaffold. Both the finite element simulation and stress relaxation constitutive model can effectively predict stress variations of cartilage scaffolds under degradation

Analysis of Knee Joint Stress During Drop Jump Landing in Females with Generalised Joint Hypermobility / 医用生物力学

Objective To analyze the differences of von Mises stress distribution in knee cartilage and meniscus in female with generalised joint hypermobility (GJH) and healthy female during drop jump landing. Methods The kinematic and ground reaction force (GRF) characteristics of knee joint in female with GJH and healthy female at the moment of peak vertical GRF (VGRF) during loading phase of drop jump landing were collected. The knee joint reaction force was calculated via inverse dynamics, and the combined force of knee joint along long axis of the femur was applied as the load. Based on three-dimensional (3D) finite element model of a female knee joint, numerical simulations were performed separately during drop jump landing of subjects in two groups, and von Mises stresses and stress distribution of knee cartilage and meniscus were calculated. Results At the moment of peak VGRF during drop jump landing, knee flexion and valgus angles in GJH group and control group showed a statistical significance (P<0. 05). Compared with control group, knee flexion angle decreased and valgus angle increased in GJH group. During drop jump landing, GJH group bore larger stress inside the knee joint, and stress distribution in weight-bearing areas of the medial and lateral tibiofemoral compartments was uneven, while the lateral femoral cartilage lateral condyle, the anterior and middle lateral of lateral tibial cartilage, the anterior angle and body lateral margin of lateral meniscus were stress concentration sites. Conclusions For females with GJH, the stability of knee joint decreases and force lines change in jumping events, due to the increased range of motion of knee joint and relaxation of joint capsule, which increases the risk of cartilage and meniscal injury in lateral knee joint. During jumping sports, females with GJH should especially prevent knee joint injury caused by altered force lines in frontal plane of knee joint.

Research Progress on Biomechanics and Mechanobiology of Articular Cartilage in 2022 / 医用生物力学

As a kind of elastic load-bearing connective tissues on bone surface in dynamic joints, articular cartilage can provide low wear lubrication, shock absorption, load transfer and other supporting functions, and has hierarchical fiber composite structures and excellent mechanical properties. As an avascular and aneural tissue,the degenerated articular cartilage lacks the capability of self-healing after damage. The high incidence of arthritisis still a hot spot in basic and clinical researches. Articular cartilage is a mechanical sensitive tissue, andmechanical environment will affect the development of tissues in different directions. Extensive researches onbiomechanics and mechanobiology of articular cartilage were conducted in 2022. Many studies on morphology, function and mechanical state of cartilage,as well as mechanical state of cartilage under different conditions were reported. Some cartilage-related loading devices were designed at animal, tissue and cell levels. Researches onthe repair of cartilage degeneration and injury under mechanical loads were carried out in vitro and in vivo, andsome important repair method and means were obtained. The biomechanical and mechanobiology research on articular cartilage is the basis of arthritis, cartilage defect and repair. The influence of quantitative mechanical under 4 conditions on the repair of articular cartilage injury needs further study in vivo and in vitro

Electroacupuncture improves motor function of rats with osteoarthritis by alleviating joint inflammation through the Wnt-7B/β-catenin signaling pathway / 南方医科大学学报

OBJECTIVE@#To investigate the effect of electroacupuncture on osteoarthritis in rats and explore the possible mechanism.@*METHODS@#Thirty SD rats were randomly divided into osteoarthritis model group, electro-acupuncture group and control group (n=10), and in the former two groups, early osteoarthritis was induced using a modified DMM surgical modeling method. After successful modeling, the rats in the electro-acupuncture group were treated with electro-acupuncture at bilateral "Housanli" and "Anterior knee point". Behavioral tests of the rats were performed and scored using the LequesneMG scale. Subchondral bone degeneration was observed in each group, and serum levels of IL-1β, ADAMTS-7, MMP-3 and COMP were measured using ELISA. The mRNA and protein expressions of IL-1β, Wnt-7B, β-catenin, ADAMTS-7, and MMP-3 in the cartilage tissue of the knee joints were detected using RT-PCR and Western blotting.@*RESULTS@#In behavioral tests, the rats in the model and electroacupuncture groups had significantly higher LequesneMG scores after modeling than those in the control group (P < 0.05). After 20 days of treatment, LequesneMG scores were significantly lowered in rats in the electroacupuncture as compared with the model rats (P < 0.05). Imaging examination revealed obvious subchondral bone damage in both the electroacupuncture group and the model group, but the damages were significantly milder with former group. Compared with the model rats, the rats receiving electroacupuncture had significantly lower serum levels of IL-1β, ADAMTS-7, MMP-3 and COMP (P < 0.05) with also lower expressions of IL-1β, Wnt-7B, β-catenin, ADAMTS-7 and MMP-3 in the cartilage tissues at both the mRNA and protein levels (P < 0.05).@*CONCLUSION@#Electroacupuncture can alleviate joint pain and improve subchondral bone damage in rats with osteoarthritis by reducing IL-1β levels in the joint cartilage tissue and serum to alleviate joint inflammation and by reducing such cytokines as ADAMTS-7 and MMP-3 via regulating the Wnt-7B/β-catenin signaling pathway.

Molecular mechanisms of tooth, maxilla and mandible development / 口腔医学

@#Understanding the pattern and molecular mechanisms of tooth, maxilla and mandible development is the prerequisite for studying their regeneration. Tooth development can be divided into three stages: bud-bell stage, tooth crown development stage and tooth root development stage. During these processes, key genes show spatial and temporal expression pattern. Tooth development is a complex process involving interactions between dental epithelium and mesenchyme, precise regulations of enamel knots in cusp patterning, as well as successful eruption into the oral cavity under proper biomechanical stress and signaling transductions. The development of tooth, maxilla and mandible, all of which originate from the first branchial arch, is independent and regulates each other to form a whole during development. Any developmental defects of them will ultimately cause defects to the others. In this paper, we briefly reviewed the development of tooth, maxilla and mandible, proposed that the homeostasis of microenvironment is critical for their development. Moreover, we reviewed the role of Meckel’s cartilage, a special structure and signaling mechanism during mandible development. At last, we proposed an integrated development model of tooth, maxilla and mandible. We also hope that the regeneration of fully functional tooth, maxilla and mandible in human can be achieved based on fundamental knowledge we have gained so far.

Natural reversal of mandibular condylar cartilage histological damage caused by chronic unpredictable moderate stress in rats / 口腔疾病防治

Objective @#To investigate the histological damage recovery of temporomandibular joint condylar cartilage caused by chronic unpredictable moderate stress, aiming to provide an experimental basis for the prevention and treatment of temporomandibular disorder.@*Methods @#This animal experiment was approved by the Laboratory Animal Ethical Inspection, School of Stomatology, The Fourth Military Medical University (No. 2020081). 60 male SD rats were randomly divided into control group, stress group, and 2-, 4- and 8-week post-stress recovery groups. Rats were subjected to chronic unpredictable moderate stress (CUMS) for 8 weeks including damp sawdust for 24 hours, tilted cage for 12 hours, noise for 4 hours, light/dark cycle reversal, water immersion, tail clamp, and restraint stress. The serum assessment, behavioral tests, histological and ultrastructural observation were performed 2-, 4- and 8-weeks after stress factors were removed. Serum levels of adrenocorticotropic hormone (ACTH) and corticosterone (CORT) were determined with ELISA. The sucrose preference test (SPT) and the forced swim test (FST) were used to assess the depressive-like behavior. The expression level of interleukin-1α (IL-1α) and matrix metalloproteinases-3 (MMP-3) were determined by Immunohistochemistry and Western blot.@*Results @#At the end of 8 weeks of CUMS, the serum levels of CORT and ACTH were significantly higher in stress group compared with control group (P<0.01). The sucrose preference decreased significantly and the immobility time increased significantly in the stressed rats compared with those in the control group, indicating a successful establishment of CUMS. The condylar cartilage showed significant degenerative changes, with disorganized collagen fibers and reduced proteoglycan synthesis on the cartilage surface. IL-1α and MMP-3 were expressed in the intracellular and extracellular matrix of the condylar cartilage, and their expression levels were increased (P<0.01). After 2 weeks of stress removal, the serum levels of CORT and ACTH were decreased but higher than control group (P<0.01), and behavioral changes were still different from the control group (P<0.01); the loosened collagen fibers could still be seen on the surface of condylar cartilage, and some free cell areas were visible within the proliferative layer; additionally, IL-1α and MMP-3 expression in the condyle was reduced in all layers of cartilage when compared with the stress group, but was still higher than in the control group (P<0.01). After 4 weeks of stress removal, the serum levels of CORT and ACTH changes returned to normal levels and behavioral changes were still different from control group (P<0.05); a few collagen fibers could be seen on the surface of the condylar cartilage and the expressions of IL-1α and MMP-3 decreased significantly compared with the stress group (P<0.01), with the similar level of IL-1α (P>0.05) and higher expression of MMP-3 comparing with the control group (P<0.01). After 8 weeks of stress removal, behavioral changes returned to normal levels, with no statistically significant differences compared with the control group (P>0.05). The condylar collagen fibers increased and showed a corrugated pattern, and no serious subchondral bone damage as well as irreversible damage occurred. Both of the expression levels of IL-1α and MMP-3 approached those of the control group after 8 weeks of stress removal (P>0.05). @*Conclusion@# The behavioral changes and condylar cartilage damage caused by CUMS could be self-repaired. The decline in IL-1α and MMP-3 expression may be one of the intrinsic mechanisms of this self-repair process.

A study on the biological effects of electromagnetic pulse with different high⁃intensity on condylar cartilage in rats / 口腔疾病防治

Objective@#To explore the biological effects of electromagnetic pulse (EMP) with different high intensities on condylar cartilage in rats. @*Methods@#SD rats were randomly divided into a sham group (Sham) and an irradiation group (EMP1: 500 kV/m, 10 Hz; EMP2: 270 kV/m, 10 Hz). Then, they were sacrificed at 1 h, 3 h, 12 h, 24 h and 3 d after irradiation. The degree of cartilage degeneration was evaluated by HE, safranine O-fast green, type Ⅱ collagen immunohistochemistry and TUNEL staining. Immunohistochemistry and western blot were performed to detect the expression of the matrix degradation factors: matrix metalloproteinase-13 (MMP-13), a disintegrin and metalloproteinase with thrombospondin motifs (ADAMTS-5) and the apoptosis key factor cleaved-cysteinyl aspartate specific proteinase (cleaved-Caspase3) in condylar cartilage. @*Results @#HE staining showed that, compared with the Sham group, a small amount of exfoliation was found on the fibrous surface layer of the cartilage after irradiation in the EMP1 and EMP2 groups. Compared with the Sham group, the percentage of safranine O-fast green-positive area decreased significantly at 12 h and 24 h (both P<0.01) in the EMP1 group and 12 h and 24 h in the EMP2 group (both P<0.05); the percentage of type Ⅱ collagen-positive area decreased significantly at 3 h and 12 h (P<0.05, P<0.001) in the EMP1 group. In addition, the number of TUNEL-positive apoptotic cells increased significantly at 1 h, 3 h, 12 h, and 24 h in the EMP1 group and 1 h, 3 h, and 12 h in the EMP2 group (P<0.05). Moreover, at different timepoints (except at 3 d) in the EMP1 group and EMP2 group, the percentage of MMP-13, ADAMTS-5- and cleaved Caspase3-positive chondrocytes and their protein levels in condylar cartilage increased significantly after irradiation (P<0.05). @* Conclusion@# EMP with a certain degree of high-intensity can induce early transient damage to condylar cartilage. This effect is dose-and time-dependent.

GPRC5B protects osteoarthritis by regulation of autophagy signaling

Osteoarthritis (OA) is one of the most common chronic diseases in the world. However, current treatment modalities mainly relieve pain and inhibit cartilage degradation, but do not promote cartilage regeneration. In this study, we show that G protein-coupled receptor class C group 5 member B (GPRC5B), an orphan G-protein-couple receptor, not only inhibits cartilage degradation, but also increases cartilage regeneration and thereby is protective against OA. We observed that Gprc5b deficient chondrocytes had an upregulation of cartilage catabolic gene expression, along with downregulation of anabolic genes in vitro. Furthermore, mice deficient in Gprc5b displayed a more severe OA phenotype in the destabilization of the medial meniscus (DMM) induced OA mouse model, with upregulation of cartilage catabolic factors and downregulation of anabolic factors, consistent with our in vitro findings. Overexpression of Gprc5b by lentiviral vectors alleviated the cartilage degeneration in DMM-induced OA mouse model by inhibiting cartilage degradation and promoting regeneration. We also assessed the molecular mechanisms downstream of Gprc5b that may mediate these observed effects and identify the role of protein kinase B (AKT)-mammalian target of rapamycin (mTOR)-autophagy signaling pathway. Thus, we demonstrate an integral role of GPRC5B in OA pathogenesis, and activation of GPRC5B has the potential in preventing the progression of OA.

Systematic evaluation of the incidence of the knee donor area after autobone cartilage mosaic xentoplasty / 中国骨伤

OBJECTIVE@#To provide an overview of the incidence of knee donor -site morbidity after autologous osteochondral mosaicplasty.@*METHODS@#A comprehensive search was conducted in PubMed, EMbase, Wanfang Medical Network, and CNKI databases from January 2010 to April 20, 2021. Relevant literature was selected based on predefined inclusion and exclusion criteria, and data were evaluated and extracted. The correlation between the number and size of transplanted osteochondral columns and donor-site morbidity was analyzed.@*RESULTS@#A total of 13 literatures were included, comprising a total of 661 patients. Statistical analysis revealed an incidence of knee donor-site morbidity at 8.6% (57/661), with knee pain being the most common complaint, accounting for 4.2%(28/661). There was no significant correlation between the number of osteochondral columns and postoperative donor-site incidence (P=0.424, N=10), nor between the diameter size of osteochondral columns and postoperative donor-site incidence(P=0.699, N=7).@*CONCLUSION@#Autologous osteochondral mosaicplasty is associated with a considerable incidence of knee donor-site morbidity, with knee pain being the most frequent complaint. There is no apparent correlation between donor-site incidence and the number and size of transplanted osteochondral columns. Donors should be informed about the potential risks.

Effectiveness of anterior cruciate ligament reconstruction with personalized femoral locator based on apex of deep cartilage / 中国修复重建外科杂志

OBJECTIVE@#To investigate the effectiveness of anterior cruciate ligament (ACL) reconstruction assisted by personalized femoral locator based on the apex of deep cartilage (ADC) combined with patient imaging data.@*METHODS@#Between January 2021 and January 2022, a total of 40 patients with primary ACL rupture were selected and randomly divided into study group (ACL reconstruction assisted by personalized femoral locator based on ADC) and control group (ACL reconstruction assisted by intraoperative fluoroscopy and traditional femoral locator), with 20 cases in each group. There was no significant difference in gender, age, body mass index, affected side, cause of injury, and preoperative International Knee Documentation Committee (IKDC) score, Lyshlom score, and Tegner score between the two groups ( P>0.05). IKDC score, Lyshlom score, and Tegner score were used to evaluate the functional recovery of the affected knee before operation and at 3, 6, and 12 months after operation. CT scan and three-dimensional reconstruction were performed before and after operation to measure the horizontal distance from ADC to the anterior cartilage margin (L) and the horizontal distance from ADC to the center of the femoral canal (I), and the anteroposterior position of the bone canal (R) was calculated by I/L; the distance from the center to the distal cartilage margin (D) was measured on the two-dimensional cross section; the R value and D value were compared between the two groups.@*RESULTS@#The operation time of the study group was significantly less than that of the control group [ MD=-6.90 (-8.78, -5.03), P<0.001]. The incisions of the two groups healed by first intention, and no complication such as intra-articular infection, nerve injury, and deep vein thrombosis of lower limbs occurred. There was no significant difference in the R value and D value between the preoperative simulated positioning and the actual intraoperative positioning in the study group [ MD=0.52 (-2.85, 3.88), P=0.758; MD=0.36 (-0.39, 1.11), P=0.351]. There was no significant difference in the actual intraoperative positioning R value and D value between the study group and the control group [ MD=1.01 (-2.57, 4.58), P=0.573; MD=0.24 (-0.34, 0.82), P=0.411]. The patients in both groups were followed up 12-13 months (mean, 12.4 months). The IKDC score, Lysholm score, and Tegner score of the two groups increased gradually with time, and there were significant differences between pre- and post-operation ( P<0.05). There was no significant difference in the scores between the two groups at each time point after operation ( P>0.05).@*CONCLUSION@#The personalized femoral locator based on ADC can accurately assist the femoral tunnel positioning in ACL reconstruction, which can shorten the operation time when compared with traditional surgical methods, and achieve satisfactory early effectiveness.

Applicatoin of chitosan-based hydrogel in oral tissue engineering / 中南大学学报(医学版)

Pulpitis, periodontitis, jaw bone defect, and temporomandibular joint damage are common oral and maxillofacial diseases in clinic, but traditional treatments are unable to restore the structure and function of the injured tissues. Due to their good biocompatibility, biodegradability, antioxidant effect, anti-inflammatory activity, and broad-spectrum antimicrobial property, chitosan-based hydrogels have shown broad applicable prospects in the field of oral tissue engineering. Quaternization, carboxymethylation, and sulfonation are common chemical modification strategies to improve the physicochemical properties and biological functions of chitosan-based hydrogels, while the construction of hydrogel composite systems via carrying porous microspheres or nanoparticles can achieve local sequential delivery of diverse drugs or bioactive factors, laying a solid foundation for the well-organized regeneration of defective tissues. Chemical cross-linking is commonly employed to fabricate irreversible permanent chitosan gels, and physical cross-linking enables the formation of reversible gel networks. Representing suitable scaffold biomaterials, several chitosan-based hydrogels transplanted with stem cells, growth factors or exosomes have been used in an attempt to regenerate oral soft and hard tissues. Currently, remarkable advances have been made in promoting the regeneration of pulp-dentin complex, cementum-periodontium-alveolar bone complex, jaw bone, and cartilage. However, the clinical translation of chitosan-based hydrogels still encounters multiple challenges. In future, more in vivo clinical exploration under the conditions of oral complex microenvironments should be performed, and the combined application of chitosan-based hydrogels and a variety of bioactive factors, biomaterials, and state-of-the-art biotechnologies can be pursued in order to realize multifaceted complete regeneration of oral tissue.

Parafoveal chondral lesion of the femoral head in patients with femoroacetabular impingement / Lesão condral parafoveal da cabeça femoral em pacientes com impacto femoroacetabular

Abstract Objective: To describe cases of parafoveal chondral lesion of the femoral head in patients with femoroacetabular impingement, correlating the clinical and imaging data. Materials and Methods: This was a retrospective descriptive case series of parafoveal chondral lesion of the femoral head in 21 patients who underwent computed tomography and magnetic resonance arthrography scans of the hip, having then received an imaging-based diagnosis of femoroacetabular impingement. Results: Of the 21 patients evaluated, 15 (71%) had cam-type femoroacetabular impingement, whereas five (24%) had mixed-type impingement, and one (5%) had pincer-type impingement. Twelve patients (57%) had a low frequency of physical activity, which was significantly associated with the presence of cam-type impingement (p = 0.015). Although the extent of the lesion correlated significantly with the acetabular coverage angle (p = 0.04), it did not correlate significantly with the alpha angle or femoral head-neck offset value (p = 0.08 and p = 0.06, respectively). We also found no correlation between the extent of the lesion and the other main parameters that define the femoroacetabular impingement types. Conclusion: This was one of the largest case series of parafoveal chondral lesion of the femoral head in patients with imaging findings of femoroacetabular impingement. The extent of such lesions does not appear to correlate with the parameters of femoroacetabular impingement, with the exception of the acetabular coverage angle.

Resumo Objetivo: Descrever casos de lesão condral parafoveal da cabeça femoral em pacientes com impacto femoroacetabular, correlacionando dados clínicos e de imagem. Materiais e Métodos: Esta foi uma série de casos descritiva retrospectiva de lesão condral parafoveal da cabeça femoral em 21 pacientes submetidos a tomografia computadorizada e artrorressonância magnética do quadril e que receberam diagnóstico por imagem de impacto femoroacetabular. Resultados: Dos 21 pacientes avaliados, 15 (71%) tiveram impacto femoroacetabular do tipo cam, enquanto cinco (24%) tiveram impacto do tipo misto e um (5%) teve impacto do tipo pincer. Doze pacientes (57%) apresentaram baixa frequência de atividade física, sendo esta significativamente associada a impacto do tipo cam (p = 0,015). Houve correlação significativa entre a extensão da lesão e o ângulo de cobertura acetabular (p = 0,04), porém, não se correlacionou significativamente com o ângulo alfa ou com o valor do deslocamento cabeça-colo femoral (p = 0,08 e p = 0,06, respectivamente). Também não encontramos correlação entre a extensão da lesão e os outros principais parâmetros que definem os tipos de impacto femoroacetabular. Conclusão: Esta foi uma das maiores casuísticas de lesão condral parafoveal da cabeça femoral em pacientes com achados de imagem de impacto femoroacetabular. A extensão dessas lesões não parece se correlacionar com os parâmetros do impacto femoroacetabular, com exceção do ângulo de cobertura acetabular.