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1.
Article de Chinois | WPRIM | ID: wpr-1021269

RÉSUMÉ

BACKGROUND:Current osteoarthritis modeling methods include anterior cruciate ligament transection(ACLT)and ACLT combined with medial meniscal anterior horn resection.ACLT requires excessive postoperative exercise,which is time and labor-intensive.Complete removal of anterior horn of the medial meniscus can cause collateral damage and increase variability in modeling outcomes,requiring higher surgical skills from the surgeon. OBJECTIVE:To modify and simplify the traditional method to create animal osteoarthritis model and compare osteoarthritis symptoms of different modeling methods under a low-load exercise environment. METHODS:Forty-eight Sprague-Dawley rats were randomly assigned in four groups(n=12 per group):sham operation(complete exposure of the knee cavity of the left hind limb followed by suturing the joint cavity and skin),ACLT,ACLT+anterior horn resection(removal of the anterior horn of the medial meniscus)and ACLT+anterior horn tear(anterior horn tear of the medial meniscus).At 4 weeks after modeling,the rats were euthanized and their knee specimens were collected for gross observation,X-ray and CT scans,pathological observation,and PCR detection. RESULTS AND CONCLUSION:Gross observation:Mild meniscal wear was observed in the ACLT group.In the ACLT+anterior horn tear group,severe wear of the lateral condyle articular surface,mild wear of the medial condyle articular surface,severe meniscal wear,and full wear of the medial meniscus were observed.The ACLT+resection group showed severe wear of the lateral condyle articular surface,mild wear of the medial condyle articular surface,absence of the anterior horn of the medial meniscus,and meniscus wear area>50%.Imaging examinations showed no significant difference among the four groups.However,the anterior tibial translocation sign was observed in the three operation groups and the anterior horn of the medial meniscus was missing in the ACLT+anterior horn resection group.Histopathological section observation:Hematoxylin-eosin,toluidine blue,and Sirius red staining showed smooth joint surfaces in the sham operation group and ACLT group;cartilage damage and matrix degradation were evident in the ACLT+anterior horn tear and ACLT+anterior horn transection groups,with less cartilage damage and matrix degradation in the ACLT+anterior horn tear group.PCR results showed higher mRNA expressions of interleukin 1β,interleukin 6,interleukin 8,tumor necrosis factor α,matrix metalloproteinase 1 and matrix metalloproteinase 3 and lower mRNA expressions of aggrecan in the ACLT+anterior horn tear group and ACLT+anterior horn resection group than in the sham operation group and ACLT group(P<0.05).The mRNA expressions of interleukin 6,matrix metalloproteinase 1,and matrix metalloproteinase 3 were higher in the ACLT + anterior horn resection group than in the ACLT +anterior horn tear group(P<0.05).To conclude,ACLT alone is less likely to induce osteoarthritis with obvious cartilage wear.ACLT combined with anterior horn resection or tear of the medial meniscus can induce obvious symptoms of osteoarthritis and achieve similar modeling effects.

2.
Article de Chinois | WPRIM | ID: wpr-1021396

RÉSUMÉ

BACKGROUND:Anterior cruciate ligament injury tends to lead to secondary meniscus injury and osteoarthritis.At present,there are few studies on the mechanics of meniscus and articular cartilage injury caused by anterior cruciate ligament injury. OBJECTIVE:To study the effect of partial rupture of the anterior cruciate ligament on the stress of medial and lateral meniscus and articular cartilage of knee joint by finite element analysis. METHODS:The CT and MRI images of the knee joint of a healthy volunteer were selected,and the scan data were imported into Mimics,Geomagic and SolidWorks software.After registration and fusion,four kinds of three-dimensional knee joint models were established:models of intact anterior cruciate ligament,rupture of the posterior external tract of anterior cruciate ligament,rupture of the anterior internal tract of anterior cruciate ligament,and absence of anterior cruciate ligament.Finally,data were imported into Ansys software to apply four different modes of loads to the knee joint:Longitudinal loads of 750 N were applied to the top of the femur;longitudinal load of 750 N to the top of the femur and forward thrust of 134 N behind tibia;a longitudinal load of 750 N and a varus moment of 10 Nm were applied to the top of the femur to simulate genu varus;750 N longitudinal load and 4 Nm internal rotation moment were applied to the proximal end of the femur to simulate knee internal rotation.The finite element analysis of biomechanical stress changes of the meniscus and articular cartilage of the knee joint was carried out. RESULTS AND CONCLUSION:(1)In the straight position of the knee joint,when the anterior medial tract of the anterior cruciate ligament was broken and the anterior cruciate ligament was missing under longitudinal loads of 750 N at the top of the femur,the total stress and peak value of meniscus increased significantly,but the stress distribution of the meniscus and the stress of articular cartilage did not change significantly.In longitudinal load of 750 N to the top of the femur and forward thrust of 134 N behind tibia,the fracture of the anterior internal tract of the anterior cruciate ligament increased the tibia forward,the compressive stress of posterior angle of the meniscus increased,and the stress of the articular cartilage did not change significantly.During simulating genu varus,the posterior angular stress of the lateral meniscus decreased,the stress of the medial meniscus increased,and the stress of articular cartilage slightly decreased when anterior cruciate ligament injuries were complete.When the anterior internal tract of the anterior cruciate ligament was broken or absent under knee internal rotation,the equivalent stress peak value of femoral cartilage and tibia cartilage shifted from medial cartilage to lateral cartilage,and the stress peak value of meniscus increased significantly.At this time,the anterior internal tract of the anterior cruciate ligament played a leading role in the rotational stability of the knee joint.(2)These results indicate that the risk of secondary meniscus injury in patients with anterior and medial anterior cruciate ligament band rupture was much higher than that in patients with posterior and external anterior cruciate ligament band rupture when the knee was in the upright standing position,varus and pronation,and there was no significant difference in the impact on articular cartilage.

3.
Article de Chinois | WPRIM | ID: wpr-1021482

RÉSUMÉ

BACKGROUND:Currently,there have been a variety of conservative and surgical treatment plans for spontaneous osteonecrosis of the knee,achieving excellent results.However,a broad consensus on indication and guide of surgical treatment has not been announced.In clinical practice,there is still a misunderstanding that unicondylar replacement or total knee arthroplasty should be performed upon the discovery of spontaneous osteonecrosis of the knee,while an urgent need for universal access to the concept of stepwise therapy. OBJECTIVE:To summarize and find the factors leading to the poor effect of conservative treatment in spontaneous osteonecrosis of the knee,which occurred on the medial femoral condyle,from the literature and clinical cases,at the same time,combined with the Koshino stage,to propose the strategy of stepwise spontaneous osteonecrosis of the knee treatment on the medial femoral condyle. METHODS:A systematic search of the literature database was conducted to summarize the factors leading to poor outcomes of conservative treatment in spontaneous osteonecrosis of the medial femoral condyle.Meanwhile,according to the Clinical&Health Records for analytics&Sharing system,the cases receiving conservative and surgical treatment in spontaneous osteonecrosis of the medial femoral condyle in the Department of Orthopedics of Guangdong Provincial Hospital of Chinese Medicine from January 2017 to January 2023 were analyzed retrospectively,then the causes of success and failure in typical cases were summarized and analyzed. RESULTS AND CONCLUSION:(1)Early diagnosis and treatment of spontaneous osteonecrosis of the knee were very important for prognosis.For sudden knee pain in some patients,if no obvious abnormality was found in the X-ray examination,and the symptoms persisted and could not be relieved for more than 1 week,an MRI examination was recommended to detect early spontaneous osteonecrosis of the knee.(2)The X-ray images of Koshino stage 1 and stage 2 of spontaneous osteonecrosis of the medial femoral condyle were difficult to be distinguished,which needed to be probed by MRI.MRI images of Koshino stage 1 were mainly characterized by bone marrow edema,and an osteonecrosis area with a clear boundary was not formed,while MR images of Koshino stage 2 showed a necrotic area with a clear boundary.(3)Five factors leading to the poor effect of conservative treatment on spontaneous osteonecrosis of the medial femoral condyle were summarized:a.The necrotic area was>5 cm2;b.The necrotic area accounted for more than 40%of the condyle;c.relative compression percentage of medial meniscus≥33%(with or without medial meniscus injury and subchondral bone marrow edema);d.MRI depth of necrotic area(anterior-posterior diameter of sagittal necrotic area)>20 mm;e.varus deformity of lower limb>6°.(4)Conservative treatment of spontaneous osteonecrosis of the knee in Koshino stage 1 was good.For spontaneous osteonecrosis of the knee in Koshino stage 2,conservative treatment was preferred or combined with drilling decompression.If there was no relief or improvement of symptoms or in MRI after 3 months,while the patient had any of the previous five factors,then knee preservation surgery should be considered.For spontaneous osteonecrosis of the knee in Koshino stage 3 and stage 4,knee preservation surgery should be selected based on the previous five factors,including age,gender and activity level of the patient.Total knee arthroplasty was used for spontaneous osteonecrosis in Koshino stage 4,which was associated with symptomatic patellofemoral arthritis,valgus alignment,or necrotic area,which greatly affected the stability of unicondyle prosthesis.

4.
Article de Chinois | WPRIM | ID: wpr-1021915

RÉSUMÉ

BACKGROUND:The traditional view is that proximal fibular fractures do not require fixation.Others and our research suggest that the proximal fibular structure plays an important role in the stability of the posterolateral structure of the knee joint,and its mechanism of action is worth studying. OBJECTIVE:To investigate the biomechanical effects of proximal fibular fractures on various structures of the knee joint in an extended state. METHODS:Finite element method was used to conduct simulated biomechanical experiments.A healthy young male volunteer was selected to establish a finite element model of the knee joint in an extended state using MRI and CT image data,and four proximal fibular shapes were simulated(Model A:intact,Model B:1 cm fracture below the fibular head,Model C:1 cm tip defect fracture from the proximal end of the fibula to the distal end,and Model D:2 cm bone defect from the proximal end of the fibula).A longitudinal concentrated load of 1 500 N was applied to the femoral shaft to compare and analyze the distribution and changing trend of the maximum equivalent stress and maximum first principal stress of each structure of the knee joint in an extended state under four working conditions. RESULTS AND CONCLUSION:(1)In Model A,the maximum equivalent stress in the tibial cartilage and lateral compartment of the meniscus was greater than that in the medial compartment,while the maximum first principal stress in the tibial plateau and medial compartment of the meniscus was greater than that in the lateral compartment.The maximum equivalent stress of the medial condyle of the femoral cartilage was greater than that of the lateral condyle,and the maximum first principal stress of the medial condyle of the femoral cartilage was greater than that of the medial condyle.(2)Compared to Model A,there was no significant difference in the magnitude and distribution of the maximum equivalent stress and maximum first principal stress in the cartilage and meniscus of Model C.(3)Compared to Model A,the maximum equivalent stress increase amplitude of Model B was in the order of medial tibial cartilage(14.9%),medial condyle of femoral cartilage(13.6%),and medial meniscus(6.6%).The maximum first principal stress increase amplitude was the medial meniscus(11.06%),the medial tibial cartilage(8.65%),and the medial condyle of the femoral cartilage(7.46%).The maximum equivalent stress increase amplitude of the ligament was as follows:popliteal arch ligament(33.2%)>anterior cruciate ligament(21.3%)>fibular collateral ligament(17%)>posterior cruciate ligament(14.3%)>anterior lateral collateral ligament(13.2%)>medial collateral ligament(10.1%).(4)Compared to Model A,the maximum equivalent stress increasing trend of Model D followed the medial tibial cartilage(19.5%),femoral cartilage medial condyle(17.9%),and medial meniscus(9.9%).The maximum first principal stress in sequence was the medial meniscus(14.04%),the medial tibial cartilage(13.03%),and the medial condyle of the femoral cartilage(11.37%).The increasing trend of maximum equivalent stress in ligaments was as follows:anterior cruciate ligament(25.2%)>posterior cruciate ligament(18.9%)>medial collateral ligament(18.5%)>anterior lateral collateral ligament(12.7%).(5)It is suggested that when the knee joint is extended,a 1 cm fracture below the fibular head and a 2 cm fibular tip bone defect have a significant impact on the structure of the medial ventricular cartilage,anterior cruciate ligament,and posterior lateral ligament complex.

5.
Article de Chinois | WPRIM | ID: wpr-1021996

RÉSUMÉ

BACKGROUND:The incidence of medial collateral ligament injuries in the knee joint is easy to lead to secondary meniscus and cartilage damage,and long-term chronic damage can lead to the occurrence of osteoarthritis.At present,there are few studies on the mechanics of meniscus and articular cartilage injury caused by medial collateral ligament rupture. OBJECTIVE:To investigate the effect of different degrees of medial collateral ligament injury on the biomechanics of meniscus and cartilage of knee joint. METHODS:The CT and MRI examinations of the knee joint of a healthy volunteer were performed to obtain the image data.The scanning data were imported into Mimics,Geomagic,and Solidworks software in turn.After registration and fusion,a 3D model of normal knee joint was established.On this basis,models of medial collateral ligament injury in different degrees of knee joint were simulated,which were divided into four groups,including:(1)medial collateral ligament was intact;(2)deep medial collateral ligament fracture;(3)superficial medial collateral ligament fracture;(4)complete rupture of medial collateral ligament.Finally,Ansys software was introduced to apply three modes of loads to the knee joint:(1)10 N·m valvaration torque was applied to the top of the femur.(2)A 4 N·m internal torque was applied to the top of the femur.(3)A 4 N·m external torque was applied to the top of the femur.The effects of four groups of models on knee biomechanics under different loads were analyzed. RESULTS AND CONCLUSION:(1)In the extension position of the knee joint,when a 10 N·m valgus torque was applied to the knee joint,the overall stress of the posterolateral meniscus increased with different degrees of medial collateral ligament injuries,while the stress of the articular cartilage did not change significantly.The peak stress of the posterolateral meniscus increased significantly with superficial medial collateral ligament rupture.(2)In the knee extension position,when a 4 N·m internal rotation torque was applied to the knee joint,the overall stress of the medial and lateral meniscus increased after different degrees of medial collateral ligament injury.When superficial medial collateral ligament rupture occurred,the peak stress of the meniscus shifted from the anterior horn of the medial meniscus to the anterior horn of the lateral meniscus.(3)In the knee extension position,applying a 4 N·m external rotation torque to the knee joint,the peak stress of the posterolateral meniscus increased more significantly than that of the medial meniscus,and the stress of the articular cartilage changed less.(4)These results show that the risk of meniscus injury secondary to superficial medial collateral ligament rupture is much higher than that of deep medial collateral ligament rupture when the knee is in extension,and the lateral meniscus is more vulnerable to injury than the medial meniscus.Both superficial medial collateral ligament and deep medial collateral ligament play an important role in the rotational stability of the knee joint.

6.
Modern Hospital ; (6): 153-155,161, 2024.
Article de Chinois | WPRIM | ID: wpr-1022223

RÉSUMÉ

Objective To analyze the effects of arthroscopic meniscus treatment on knee osteoarthritis on the effective rate,VAS score,HSS score and TNF-α level.Methods We selected 86 patients with knee osteoarthritis caused by meniscus injury who were treated in our hospital from June 2019 to May 2020 as the research subjects.The treatment method was selected according to the patient's wishes,with 43 patients who chose conventional conservative treatment included in the control group and 43 patients who chose arthroscopic meniscus therapy included in the study group.The treatment effectiveness,visual ana-logue scale(VAS)score,HSS knee joint score and tumor necrosis factor-α(TNF-α)index levels were compared between the two groups of patients.Results The effective rate of treatment in the study group was significantly higher than that in the control group(P<0.05);there was no significant difference between the study group and the control group in the VAS score,HSS score,and TNF-α level before treatment(P>0.05).After treatment,the VAS score,HSS score and TNF-α level of the group were improved.The VAS score and TNF-α level of the study group after treatment were lower than those of the control group(P<0.05),and the HSS score was higher than the control group.Group(P<0.05).Conclusion The arthroscopic meniscus treatment for patients with knee osteoarthritis has a significant effect,which can effectively reduce the pain and inflammation of the patients and improve the function of the knee joint.

7.
Journal of Medical Biomechanics ; (6): 111-117, 2024.
Article de Chinois | WPRIM | ID: wpr-1023780

RÉSUMÉ

Objective The biomechanical model for the musculoskeletal system of a human knee joint was established using a numerical simulation method.The kinematic and dynamic information captured during jumping motion simulated by the human dynamic model was used as driven data of the knee biomechanical model,followed by further analysis of the stress field distribution characteristics of the meniscus under different thermal-force coupling knee brace conditions.Methods Based on computed tomography and magnetic resonance imaging of the subject,a realistic human knee model,including bone,articular cartilage,meniscus,ligaments and peripheral soft tissues of the knee joint,was constructed.Furthermore,two gaits,namely taking-off and landing-on,of jumping motion with an increased risk of meniscus injuries were selected according to mechanical features in full-cycle jumping motion.Subsequently,the stress field characteristics of the knee meniscus under four different thermal-force coupling knee braces were analyzed,the changes of the peak stress of the meniscus and its stress concentration area were discussed,and the protective efficacy and mechanical basis of meniscal injuries and wearing knee braces were explored.Results The anterior part of the medial knee meniscus was a vulnerable area under concentrated stress.Under the knee brace thermal-force coupling condition,the stress concentration area of the medial meniscus was transferred from its narrow and weak anterior part to its wide and thick middle part,and the peak stress was also significantly reduced.The peak stress on the medial meniscus and that on the lateral meniscus were similar,indicating that the two parts of the meniscus bore the external load evenly,and the meniscus stress concentration area decreased.Conclusions Thermal-force coupling knee braces have good protective effects against knee meniscus injury.The numerical simulation provides theoretical support and technical guidance for the design of multifunctional thermal knee braces.

8.
Chinese Journal of Orthopaedics ; (12): 287-293, 2024.
Article de Chinois | WPRIM | ID: wpr-1027719

RÉSUMÉ

Objective:To analyze the effect of mucosal ligament preservation on the outcome of arthroscopic repair of meniscus injury.Methods:A total of 77 patients with knee meniscus tears caused by sports injuries who underwent arthroscopic meniscus repair or suture in Zhengzhou Orthopaedic Hospital from June 2022 to June 2023, were retrospectively analyzed. Including 45 males and 32 females, aged 38.57±13.54 years (range, 52-87 years), body mass index 24.72±4.01 kg/m 2 (range, 34.14-13.61 kg/m 2). All patients complained of knee pain, limited activity and walking weakness. The symptoms were not relieved after 1 month of conservative treatment, which seriously affected daily work and life. According to the intraoperative treatment of mucosal ligament, the patients were divided into mucosal ligament preservation group and mucosal ligament removal group. The visual analogue score (VAS), Lysholm score, and total blood loss were compared between the two groups. Results:All patients successfully completed the operation and were followed up for an average of 5.23±2.16 months (range, 3-9 months). The operation time was 47.59±16.81 min in mucosal ligament preservation group and 45.25±15.93 min in mucosal ligament removal group, and there was no significant difference between the two groups ( t=0.628, P=0.532). The total blood loss in the mucosal ligament preservation group was 246±193 ml, which was less than 343±211 ml in the mucosal ligament removal group, and the difference was statistically significant ( t=2.095, P=0.040). None of the patients received allogeneic blood transfusion. The hematocrit of the mucosal ligament preservation group was 42.48%±4.57% before operation and 39.42%±4.65% on the third day after operation, while that of the mucosal ligament removal group was 41.24%±4.16% and 38.95%±3.80%. The difference between the two groups was statistically significant ( t=0.016, P=0.004; t=0.004, P=0.016). There was no significant difference between the two groups before operation and on the third day after operation ( t=0.217, P=0.545; t=0.629, P=0.159). The preoperative VAS score of mucosal ligament preservation group was 7.25±1.10, which was higher than that of 3 months after operation (0.83±1.06), and the difference was statistically significant ( t=0.062, P<0.001). The preoperative VAS score of mucosal ligament removal group was 7.16±1.21, which was higher than that of 3 months after operation (1.05±1.13), and the difference was statistically significant ( t=0.017, P<0.001). There was no significant difference in VAS scores between the two groups before operation and at 3 months after operation ( t=0.144, P=0.740; t= 0.273, P=0.603). The preoperative Lysholm score of mucosal ligament preservation group was 31.76±7.54, which was significantly lower than that of 3 months after operation 87.30±4.12 ( t=-39.329, P<0.001); The Lysholm score of the mucosal ligament removal group was 34.13±7.32 before operation, which was lower than 89.05±4.45 at 3 months after operation, and the difference was statistically significant ( t=-40.172, P<0.001); There was no significant difference in Lysholm score between the two groups before operation and 3 months after operation ( t=1.395, P=0.167; t=1.766, P=0.081). Conclusion:The preservation of mucosal ligament in arthroscopic surgery for meniscus injury does not prolong the operation time. It can reduce the total intraoperative blood loss, and the postoperative knee function recovery is similar to that of mucosal ligament removal.

9.
Article de Chinois | WPRIM | ID: wpr-1017298

RÉSUMÉ

Objective:The pain-relieving effect and safety of compound aminopyrine phenacetin tab-lets,tramcontin(tramadol hydrochloride sustained-release tablets)and dolantin in the early stage of au-tologous tendon reconstruction of the anterior cruciate ligament(ACL)of the knee joint were compared.Methods:Retrospective analysis of postoperative pain and drug analgesia in 45 patients performed by the same group from November 2018 to February 2019.The random area group design was divided into two groups according to whether ACL rupture was combined with meniscal injury,group A was 24 patients with ACL reconstruction of knee joint and group B was 21 patients with ACL fracture combined with me-niscus injury.The two groups were divided into three subgroups respectively according to the actual treat-ment of postoperative analgesic drugs received by the patients,including 4 cases of compound aminopy-rine phenacetin tablets,11 cases of oral tramcontin,9 cases of intramuscular dolantin combined with phenergan in group A;3 cases of compound aminopyrine phenacetin tablets,10 cases of oral tramcontin,and 8 cases of intramuscular dolantin combined with phenergan in group B.When the early postoperative patients complain about pain and actively ask for analgesia.When the patients complained about pain af-ter the operation and actively asked for analgesia,they were randomly given painkillers,tramcontin or do-lantin combined with phenergan to relieve pain.Pain visual analogue scale(VAS)was used to evaluate pain relief and observe the occurrence of adverse reactions.Results:There were no significant dif-ferences in gender,age,body mass index,and time of hospital stay between the two groups of patients(P>0.05).In the patients who used tramcontin and dolantin combined with phenergan to relieve pain judging by VAS score before and 1 h after taking the drug,it was found that the pain situation of the pa-tient was significantly relieved,and the difference before and after taking the drug had statistical signifi-cance(P<0.05).Pairwise comparisons of the three drugs applied in the two groups showed significantly greater pain relief in the dolantin combined with phenergan group than in the remaining two drugs.There was no significant difference(P>0.05).Dolantin was prone to nausea and vomiting,but the application of phenergan was also used to reduce side effects.In terms of adverse reactions,only 1 case of nausea oc-curred in the tramcontin group for simple ACL reconstruction,and none of the patients in the other groups showed serious complications and allergic reactions.Conclusion:Whether in cruciate ligament recon-struction alone or combined with meniscus molding or suture,compound aminopyrine phenacetin tablets,tramcontin,dolantin combined with phenergan can effectively relieve pain.Among the three drugs,do-lantin caused the largest pain relief.At the same time,the combination of phenergan effectively reduced the adverse reactions,such as vomiting and nausea,and increased the drug safety.

10.
Journal of Army Medical University ; (semimonthly): 283-287, 2024.
Article de Chinois | WPRIM | ID: wpr-1017559

RÉSUMÉ

Objective To compare the differences in lower limb force line between degenerative medial meniscus injuries and lateral meniscus injuries and investigate their correlation.Methods A total of 90 patients who underwent arthroscopic treatment for meniscal injuries between March 2019 and March 2022 were enrolled in the study.They were 45 males and 45 females,at a median age of 52 years(ranging from 40 to 59 years).Of these patients,47 had medial meniscus injuries,while 43 had lateral meniscus injuries.The hip-knee-ankle(HKA)angle was measured on full-length films,and the differences were compared between the 2 groups.Results There were no significant differences in terms of gender,age,lower limb laterality,body mass index,site of injury,and type of injury between the medial meniscus injury group and the lateral meniscus injury group.Statistical difference was observed in the mean HKA angle,with a value of(177.20±2.46)° in the medial meniscus injury group and of(181.05±3.13)° in the lateral meniscus injury group(P<0.01).Conclusion There is a significant difference in HKA angle between medial meniscus injury group and the lateral meniscus injury group.A correlation is found between lower limb alignment and degenerative meniscus injury.

11.
Article de Chinois | WPRIM | ID: wpr-1009231

RÉSUMÉ

The discoid meniscus is a common congenital meniscal malformation that is prevalent mainly in Asians and often occurs in the lateral discoid meniscus. Patients with asymptomatic discoid meniscus are usually treated by conservative methods such as observation and injury avoidance, while patients with symptoms and tears need to be treated surgically. Arthroscopic saucerization combined with partial meniscectomy and meniscus repair is the most common surgical approach., and early to mid-term reports are good. The prognostic factors are the patient's age at surgery、follow-up time and type of surgery. Some patients experience complications such as prolonged postoperative knee pain, early osteoarthritis, retears and Osteochondritis dissecans. The incidence of prolonged postoperative knee pain was higher and the incidence of Osteochondritis dissecans was the lowest. Retears of the lateral meniscus is the main reason for reoperation.


Sujet(s)
Enfant , Humains , Ostéochondrite disséquante , Résultat thérapeutique , Études de suivi , Articulation du genou/chirurgie , Ménisques de l'articulation du genou/chirurgie , Maladies articulaires/chirurgie , Pronostic , Maladies du cartilage/chirurgie , Ménisque , Douleur postopératoire , Arthroscopie/méthodes
12.
Rev. bras. entomol ; Rev. bras. entomol;68(3): e20240036, 2024. graf
Article de Anglais | LILACS-Express | LILACS | ID: biblio-1569697

RÉSUMÉ

ABSTRACT This study provides a description of the female and a redescription of the male terminalia of Dixella woodi Chaverri & Borkent, 2007, which is recorded in Peru for the first time. Diagnoses for the other two Peruvian Dixidae species, Dixella andeana (Lane, 1942) and Dixella peruviana (Edwards, 1931), and remarks on their types are presented along with a key to distinguish the three species. Dixella woodi differs significantly from other Neotropical Dixella Dyar & Shannon, 1924 species, such as the presence of elongated setae on the medial portion of the katepisternum and unique characteristics in both male and female terminalia. The findings underscore the importance of systematic collection sampling and taxonomic revision in the Neotropical region to advance our understanding of Dixidae diversity and distribution.

13.
Rev. Bras. Ortop. (Online) ; 59(2): 199-205, 2024. tab
Article de Anglais | LILACS | ID: biblio-1565373

RÉSUMÉ

Abstract Objective This study aimed to identify the main knee complaints and injuries associated with baseball and their prevalence in the state of São Paulo, Brazil. Methods This epidemiological study analyzed data from an online questionnaire sent to baseball athletes from the state of São Paulo, Brazil, from 2019 to 2022. Results Ninety-eight athletes participated in the study. Their average age was 24.3 years, and 85.72% of the subjects were men. The most prevalent ethnicities were yellow (50%) and white (42.86%). Most athletes had incomplete or complete higher education (75.5%). Most (88.77%) have been training for over 1 year, and 40.82% played in more than 1 position. More than half also practiced another sport. Most (66.32%) athletes present knee complaints or symptoms, and 37.75% had suffered a knee injury playing baseball, with several mechanisms (contact with the ground, contact with another player, or no contact). More than half (59.45%) of the athletes required time away from baseball due to complaints, symptoms, or injuries. Conclusion Among the athletes interviewed, 66.32% had a knee complaint, and 37.75% had already had a knee injury, especially meniscal and ligament injuries. The injury rate was highest in the first year of practice.


Resumo Objetivo Identificar as principais queixas e lesões de joelho associadas ao beisebol, e sua prevalência em atletas de beisebol no estado de São Paulo. Métodos Estudo epidemiológico desenvolvido por meio da análise de dados obtidos por um questionário online, entre os anos de 2019 e 2022, distribuído entre atletas de beisebol do estado de São Paulo. Resultados Noventa e oito atletas participaram do estudo, com média de 24,3 anos de idade, sendo que 85,72% eram homens. As etnias mais prevalentes foram os amarelos (50%) e brancos (42,86%), e a maioria dos atletas possuía ensino superior incompleto ou completo (75,5%). Um total de 88,77% treinava há mais de 1 ano e 40,82% atuavam em mais de uma posição. Mais da metade praticava simultaneamente outro esporte. Um total de 66,32% dos atletas apresentava queixas ou sintomas no joelho e 37,75% já haviam sofrido alguma lesão no joelho associada à prática do beisebol através de diversos mecanismos (contato com solo, contato com outro jogador, sem contato). Um total de 59,45% dos atletas precisou ser afastado da prática devido às queixas, sintomas ou lesões apresentadas. Conclusão Dos atletas entrevistados, 66,32% apresentaram alguma queixa no joelho e 37,75% já tiveram alguma lesão diagnosticada nessa articulação, sendo as mais prevalentes as lesões meniscais e as ligamentares. A taxa de lesões foi maior no primeiro ano de prática.


Sujet(s)
Humains , Mâle , Femelle , Baseball , Tendinopathie , Athlètes , Lésions du ménisque externe , Traumatismes du genou/épidémiologie
14.
Acta ortop. mex ; 37(6): 356-360, nov.-dic. 2023. tab, graf
Article de Espagnol | LILACS-Express | LILACS | ID: biblio-1573760

RÉSUMÉ

Resumen: Introducción: existe escasa información de la reparación meniscal en la población pediátrica en cuanto a resultados de esta técnica. Los objetivos de este estudio fueron evaluar los resultados clínicos y las complicaciones de la reparación meniscal en población pediátrica con lesiones aisladas, asociadas a ruptura del LCA y menisco discoide con lesiones inestables. Material y métodos: los datos de 78 pacientes ≤ 18 años de edad, con diagnóstico artroscópico de lesión meniscal aislada, asociada a rotura del ligamento cruzado anterior (LCA) o menisco discoide, en los que se realizó reparación artroscópica, se analizaron retrospectivamente. Los resultados funcionales fueron valorados con las escalas de Lysholm y Pedi-IKDC. El tiempo hasta la falla de la reparación se definió como el intervalo entre la reparación meniscal hasta la revisión artroscópica. Resultados: la edad media fue de 14 años (DE 3.1, rango 3-19). Los pacientes del grupo C eran significativamente más jóvenes (15.4 años en el grupo A frente a 1.9 en el grupo B frente a 12.1 en el grupo C, p = 0.001). El seguimiento medio fue de 33.8 meses. La puntuación media de Lysholm y Pedi-IKDC fueron 96.1 puntos (rango, 76-100) y 93.8 puntos (rango, 59.8-100), respectivamente. La tasa de fallas global fue de 14.1% (11/78). Hubo 4 (13%) fallas en el grupo A, 3 fallas (12%) en grupo B, y 5 fallas (17%) en el grupo C (p = 0.429). Encontramos una tendencia a un mayor número de fallas en las lesiones por mango de cubo (p = 0.08) y una asociación significativa cuando se utilizaron ≥ 4 suturas (p = 0.041). Conclusiones: la reparación meniscal demostró una tasa de éxito clínico de 85.9%. Los pacientes con menisco discoide, lesiones asa de balde y aquellos que requirieron mayor número de suturas presentaron un mayor riesgo de falla. La reparación debe considerarse como la primera opción de tratamiento quirúrgico para la mayoría de las lesiones meniscales en niños y adolescentes.


Abstract: Introduction: there is scarce information on meniscal repair in the paediatric population in terms of outcomes of this technique. The aim of this study was to evaluate the clinical outcomes and complications of meniscal repair in paediatric population with isolated lesions, associated with ACL rupture and discoid meniscus with unstable lesions. Material and methods: data from 78 patients ≤ 18 years of age, with arthroscopic diagnosis of isolated meniscal lesion, associated with ACL tear or discoid meniscus, in whom arthroscopic repair was performed, were retrospectively analyzed for demographic characteristics, surgical technique, and perioperative complications. Functional results were assessed with the Lysholm and Pedi-IKDC scales. Time to repair failure was defined as the interval between meniscal repair and revision (re-repair or subtotal meniscectomy). Results: mean age was 14 years (SD 3.1, range 3-19). The patients in group C were significantly younger (15.4 years in group A vs 14.9 in group B vs 12.1 in group C, p = 0.001). The average follow-up was 33.8 months. The mean Lysholm score and Pedi-IKDC were 96.1 points (range, 76-100) and 93.8 points (range, 59.8-100), respectively. The overall failure rate was 14.1% (11/78). There were 4 (13%) failures in group A, 3 failures (12%) in group B, and 5 failures (17%) in group C (p = 0.429). We found a tendency towards a greater number of failures in bucket handle injuries (p = 0.08) and a significant association when ≥ 4 sutures were used (p = 0.041). Conclusion: in this series, meniscal repair demonstrated a clinical success rate of 85.9%. Patients with discoid meniscus, bucket handle injuries, and those who required a greater number of sutures had a higher risk of failure. Repair should be considered the first surgical treatment option for most meniscal injuries in children and adolescents.

15.
Radiol. bras ; Radiol. bras;56(6): 336-342, Nov.-Dec. 2023. tab, graf
Article de Anglais | LILACS-Express | LILACS | ID: biblio-1535044

RÉSUMÉ

Abstract Objective: To determine whether being a smoker and the years of smoking correlate with the presence and degree of meniscal injury. Materials and Methods: Individuals who underwent magnetic resonance imaging of the knee were divided into two groups: smokers and nonsmokers. For each smoker, the total smoking history was calculated by multiplying the daily consumption (packs/day) by the years of smoking, and the result is expressed as pack-years. In the evaluation of meniscal injury, the grade of injury was recorded. The thickness of the subcutaneous adipose tissue, as an indicator of obesity, was measured at the medial knee on axial plane images. The relationships that smoking and obesity had with meniscal injury were analyzed statistically. Results: A total of 156 individuals were included in the study. The smoker group consisted of 48 individuals (30.8%), and the nonsmoker group consisted of 108 (69.2%). The meniscus was normal in one (2.1%) of the smokers and in 32 (29.6%) of the nonsmokers (p < 0.0001). The median subcutaneous adipose tissue thickness was 23 mm and 24 mm in the smokers and nonsmokers, respectively (p = 0.900). A moderate but statistically significant correlation was observed between packs/day and injury grade, as well as between pack-years and injury grade (r = 0.462, p = 0.001 and r = 0.523, p = 0.001, respectively). Smoking and age significantly increased the risk of meniscal injury, by 31.221 times (p = 0.001) and 1.076 times (p < 0.001), respectively. Conclusion: Our findings indicate that current smoking and smoking history correlate significantly with meniscal injury grade.


Resumo Objetivo: Determinar a correlação do tabagismo e do tempo de tabagismo com a presença e o grau de lesão do menisco. Materiais e Métodos: Foram incluídos pacientes submetidos a ressonância magnética do joelho e divididos em dois grupos: fumantes e não fumantes. O consumo total de cigarros dos pacientes foi calculado multiplicando-se a quantidade diária de cigarros (maços/dia) pelo tempo de tabagismo (anos). O grau mais alto de lesão foi registrado na avaliação da lesão meniscal. A espessura do tecido adiposo subcutâneo foi medida com base em imagem do joelho em plano axial, como indicador de obesidade. A relação entre tabagismo, obesidade e lesão meniscal foi analisada estatisticamente. Resultados: Foram incluídos no estudo 156 indivíduos. O grupo de fumantes consistiu de 48 (30,8%) indivíduos e o grupo de não fumantes, de 108 (69,2%) indivíduos. O menisco estava normal em um (2,1%) fumante e em 32 (29,6%) não fumantes (p < 0,0001). A espessura média do tecido adiposo subcutâneo em fumantes foi 23 mm e nos não fumantes foi 24 mm, com valor de p = 0,900. Foi observada correlação moderada e estatisticamente significante entre o grau de lesão por pacote/dia (r = 0,462, p = 0,001) e o grau de lesão por pacote × ano (r = 0,523, p = 0,001). O tabagismo e a idade afetaram significativamente o risco de lesão do menisco (31,221 vezes, p = 0,001 e 1,076 vez, p < 0,001, respectivamente). Conclusão: Foi encontrada correlação significativa entre tabagismo/dia e grau de lesão do menisco e pacote de tabagismo × ano e grau de lesão do menisco.

16.
Acta ortop. mex ; 37(5): 302-308, sep.-oct. 2023. graf
Article de Espagnol | LILACS-Express | LILACS | ID: biblio-1573750

RÉSUMÉ

Resumen: La ruptura de ligamento cruzado anterior (LCA) es una patología epidemiológicamente muy importante en nuestro medio. Tiene un pico de incidencia entre los 16 a 39 años de edad. Se calcula que entre 70-84% de las lesiones de LCA son sin contacto. La posición de «no retorno¼ describe a la rodilla en valgo, rotación externa femoral, rotación interna tibial y semiflexión, promoviendo la lesión de este ligamento. Las medidas geométricas de la rodilla se han asociado con un aumento en la probabilidad de lesión del LCA sin contacto. La ruptura crónica del LCA conlleva al desarrollo de artrosis en pacientes jóvenes. El manejo de la ruptura del LCA se divide en dos: tratamiento conservador y manejo quirúrgico. La osteoartrosis temprana es la consecuencia más común de la ruptura del LCA. Presentamos el caso de un paciente de 35 años con ruptura inveterada del LCA de 10 años de evolución. Con manejo conservador inicialmente que progresa a inestabilidad de rodilla y dolor en línea articular medial y lateral, así como aumento de volumen y limitación funcional. Tras estudios diagnósticos, se decide realizar artroscopía diagnóstica-terapéutica y se continúa con seguimiento estrecho por patología asociada.


Abstract: Anterior cruciate ligament (ACL) rupture is a very important epidemiological pathology in our environment. It has a peak incidence between 16 to 39 years of age. It is estimated that between 70-84% of ACL injuries are non-contact. The «no return¼ position describes the knee in valgus, femoral external rotation, tibial internal rotation and semiflexion, promoting injury to this ligament. Geometric measurements of the knee have been associated with an increased probability of non-contact ACL injury. The management of ACL tears is divided into two: conservative treatment and surgical management. Early OA (osteoarthritis) is the most common consequence of an ACL tear. We present the case of a 35-year-old patient with an inveterate ACL rupture of 10 years of evolution. With conservative management initially that progresses to knee instability and pain in the medial and lateral joint line as well as increased volume and functional limitation. After diagnostic studies, it was decided to perform diagnostic-therapeutic arthroscopy and continued close follow-up for associated pathology.

17.
Indian J Ophthalmol ; 2023 Jul; 71(7): 2704-2710
Article | IMSEAR | ID: sea-225134

RÉSUMÉ

Purpose: To compare the tear meniscus height (TMH) and tear meniscus depth (TMD) between medically controlled glaucoma subjects and age?matched controls. Methods: This prospective, cross?sectional, observational study included 50 patients with medically controlled glaucoma and 50 age?matched controls. Glaucoma subjects using topical medications for the duration of more than 1 year were included. The age?matched controls were participants with no history of glaucoma, dry eye, or any other diseases affecting the ocular surface. All the participants underwent TMH and TMD scan using spectral domain?optical coherence tomography (SD?OCT), which was followed by ocular surface disease index (OSDI) questionnaire administration. Results: The mean ages of glaucoma subjects and age?matched controls were 40 ± 22 and 39 ± 21 years, respectively (P > 0.05). Of them, 40% (n = 22) were on single drug therapy or monotherapy and 60% (n = 28) were on multidrug therapy. TMH and TMD of glaucoma subjects and age?matched controls were 101.27 ± 31.86 versus 230.63 ± 49.82 ?m and 70.60 ± 27.41 versus 167.37 ± 57.06 ?m, respectively. Subjects on multidrug therapy showed a statistically significant reduction in TMH and TMD when compared to age?matched controls. Conclusion: Preservative containing topical glaucoma medications affects the ocular surface, including the tear film. The prolonged duration and multiple combination of this drug usage serve as potential factors for causing reduction in the tear meniscus levels leading to drug?induced dryness

18.
Acta ortop. mex ; 37(3): 152-158, may.-jun. 2023. tab, graf
Article de Espagnol | LILACS-Express | LILACS | ID: biblio-1556750

RÉSUMÉ

Resumen: Introducción: los dispositivos de suturas meniscal todo adentro han evolucionado y simplificado la reparación meniscal. En este estudio formulamos las siguientes preguntas de investigación: ¿cuál es la tasa de supervivencia y falla?, ¿cuáles son los factores de riesgo asociado a falla? y ¿cuáles son los resultados funcionales posterior a la cirugía de reparación meniscal? Material y métodos: estudio ambispectivo desde el 2001 al 2021 de pacientes con lesión meniscal reparable con dispositivos meniscales de sutura todo adentro. La razón de supervivencia y falla se obtuvo con el test de Kaplan-Meier, los factores de riesgo asociado con falla de la sutura meniscal se valoraron con el test de regresión logística y los resultados funcionales pre y postquirúrgicos fueron estimados con la prueba t-Student. Resultados: en 20 años de seguimiento de 316 menisco reparados con suturas meniscal todo adentro se obtuvo que la razón de supervivencia de 95.9%. La ausencia de lesión del cuerno anterior del menisco se mostró como un factor protector [OR = 0.12], junto a la no práctica de deportes de impacto [OR = 0.2]. Se mostraron resultados del IKDC y Tegner-Lysholm posterior a la cirugía de muy buenos a excelentes (p < 0.0001). Conclusión: los dispositivos de sutura de meniscal todo adentro son y seguirán siendo armas de primera línea en la reparación de las roturas meniscales. En 20 años de seguimiento se evidenció una menor tasa de falla, asociados con excelentes resultados funcionales.


Abstract: Introduction: all-in meniscal suture devices have evolved and simplified meniscal repair. In this study we will formulate the following research questions: what is the rate of survival and failure? What are the risk factors associated with failure? And what are the functional results after meniscal repair surgery? Material and methods: ambispective study from 2001 to 2021 of patients with repairable meniscal injury with all-in meniscal suture devices. The survival and failure ratio were obtained with the Kaplan-Meier test, the risk factors associated with meniscal suture failure were assessed with the logistic regression test, and the pre- and post-surgical functional results were estimated with the test. t-Student. Results: in 20 years of follow-up of 316 menisci repaired with all-in meniscal sutures, a survival rate of 95.9% was obtained. The absence of injury to the anterior horn of the meniscus was shown to be a protective factor [OR = 0.12], together with not practicing impact sports [OR = 0.2]. Post-surgery IKDC and Tegner-Lysholm results were shown to be very good to excellent (p < 0.0001). Conclusion: all-in meniscal suture devices are and will continue to be front-line weapons in the repair of meniscal tears. In 20 years of follow-up, a lower failure rate was evidenced, associated with excellent functional results.

19.
Radiol. bras ; Radiol. bras;56(3): 131-136, May-June 2023. tab, graf
Article de Anglais | LILACS-Express | LILACS | ID: biblio-1449040

RÉSUMÉ

Abstract Objective: To characterize the location of tibial edema related to meniscal degeneration with a flap displaced into the meniscotibial recess (osteomeniscal impingement) on magnetic resonance imaging (MRI). Materials and Methods: We evaluated 40 MRI examinations of patients submitted to surgery due to inferior displacement of a meniscal flap tear into the meniscotibial recess and peripheral bone edema. Tibial edema was quantified in the coronal and axial planes. Results: On coronal MRI sequences, edema started in the tibial periphery and extended for a mean of 5.6 ± 1.4 mm, or 7.4 ± 2.1% of the tibial plateau. In the craniocaudal direction, the mean extension was 8.8 ± 2.9 mm. The mean ratio between the extent of craniocaudal and mediolateral edema was 1.6 ± 0.6. In the axial plane, the edema started in the medial periphery and extended for a mean of 6.2 ± 2.0 mm, or 8.2 ± 2.9% of the tibial plateau. In the anteroposterior measurement, the mean start and end of the edema was 21.4 ± 5.4 mm and 35.7 ± 5.7 mm, respectively, or 43.4 ± 10.2% and 72.8 ± 11.1% of the tibial plateau. Conclusion: Apparently, tibial edema resulting from osteomeniscal impingement always starts in the periphery of the meniscus. In the coronal plane, it appears to be more extensive in the craniocaudal direction than in the mediolateral direction. In the axial plane, we found it to extend, on average, approximately 6.2 mm in the mediolateral direction and to be most commonly located from the center to the posterior region of the medial tibial plateau.


Resumo Objetivo: Caracterizar a localização do edema ósseo tibial relacionado a lesão meniscal degenerativa com fragmento deslocado no recesso meniscotibial (impacto osteomeniscal) por meio de ressonância magnética (RM). Materiais e Métodos: Quarenta RMs de pacientes submetidos a cirurgia por fragmento deslocado do menisco medial no recesso meniscotibial e edema ósseo periférico foram avaliadas. Edema ósseo tibial foi quantificado nos planos coronal e axial. Resultados: No plano coronal, o edema iniciou-se na periferia tibial e estendeu-se por 5,6 ± 1,4 mm, ou 7,4 ± 2,1% do platô. Na direção craniocaudal, o edema estendeu-se em média 8,8 ± 2,9 mm. A média entre a extensão do edema craniocaudal e mediolateral foi 1,6 ± 0,6. No plano axial, o edema iniciou-se na periferia medial e estendeu-se por 6,2 ± 2,0 mm, ou 8,2 ± 2,9% da medida da tíbia. Na medida anteroposterior, o edema iniciou-se em 21,4 ± 5,4 mm e terminou em 35,7 ± 5,7 mm ou iniciou-se em 43,4 ± 10,2% e terminou em 72,8 ± 11,1% do platô tibial. Conclusão: O edema ósseo tibial relacionado aos casos de impacto osteomeniscal sempre se inicia na periferia do menisco. Ele é mais extenso na direção craniocaudal do que mediolateral no plano coronal. No plano axial, ele estende-se por 6,2 mm de medial a lateral e é mais frequentemente localizado no centro da região posterior do platô medial.

20.
Rev. Bras. Ortop. (Online) ; 58(2): 206-210, Mar.-Apr. 2023. tab, graf
Article de Anglais | LILACS | ID: biblio-1449791

RÉSUMÉ

Abstract Objectives To perform a systematic review of the literature on the anatomy of the medial meniscotibial ligaments (MTLs), and to present the most accepted findings, as well as the evolution of the anatomical knowledge on this structure. Materials and Methods An electronic search was conducted in the MEDLINE/PubMed, Google Scholar, EMBASE and Cochrane library databases with no date restrictions. The following index terms were used in the search: anatomy AND meniscotibial AND ligament AND medial. The review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. We included anatomical studies of the knee were included, such as cadaver dissections, histological and/or biological investigations, and/or imaging of the medial MTL anatomy. Results Eight articles that met the inclusion criteria were selected. The first article was published in 1984 and the last, in 2020. The total sample in the 8 articles was of 96 patients. Most studies are purely descriptive in terms of the macroscopic morphological and microscopic histological findings. Two studies evaluated the biomechanical aspects of the MTL, and one, the anatomical correlation with the magnetic resonance imaging examination. Conclusion The main function of the medial MTL, a ligament that originates in the tibia and is inserted in the lower meniscus, is to stabilize and maintain the meniscus in its position on the tibial plateau. However, there is a limited amount of information regarding medial MTLs, primarily in terms of anatomy, especially vascularization and innervation.


Resumo Objetivos Fazer uma revisão sistemática da literatura sobre a anatomia dos ligamentos meniscotibiais (LMTs) mediais, e apresentar os achados mais aceitos e a evolução das informações anatômicas sobre essa estrutura. Materiais e Métodos A busca eletrônica foi realizada nos bancos de dados MEDLINE/PubMed, Google Scholar, EMBASE e Cochrane, sem restrições de data. Os seguintes termos de indexação foram utilizados: anatomy AND meniscotibial AND ligament AND medial. A revisão seguiu as recomendações da declaração de Principais Itens para Relatar Revisões Sistemáticas e Metanálises (Preferred Reporting Items for Systematic Reviews and Meta-Analyses, PRISMA, em inglês). Foram incluídos estudos anatômicos do joelho, como dissecções de cadáveres, investigações histológicas e/ou biológicas, e/ou imagens da anatomia do LMT medial. Resultados Oito artigos atenderam aos critérios de inclusão e foram selecionados. O primeiro foi publicado em 1984, e o último, em 2020. A amostra total nos 8 artigos foi de 96 pacientes. A maioria dos estudos é puramente descritiva em relação aos achados morfológicos macroscópicos e histológicos microscópicos. Dois estudos avaliaram os aspectos biomecânicos do LMT, e um analisou a correlação anatômica com o exame de ressonância magnética. Conclusão A principal função do LMT medial, ligamento que se origina na tíbia e se insere no menisco inferior, é estabilizar e manter a posição do menisco no platô tibial.


Sujet(s)
Humains , Tibia/anatomie et histologie , Ménisque/anatomie et histologie , Genou/anatomie et histologie , Ligaments
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