Objective To study degradation of the antigen-extracted meniscus in PBS solution with no enzyme or with different enzymes. Methods Four types of enzymes (collagenase, hyaluronidase, trypsin, papain) were used to enzymolyze the antigen-extracted meniscus and the fresh meniscus for 3, 7, 15 and 30 days (37℃). The antigenextracted meniscus and the fresh meniscus were immersed in PBS solution (37℃) for 30 days. Weight loss measurement, UV spectrophotometry, and scanning electron microscopy (SEM) were used to characterize the degraded materials. Results The two types of the materials were remarkably digested under the enzymes, especially under trypsin. The degradation curves showed that the antigen-extracted meniscus was enzymolyzed less than the fresh meniscus. The degradation products were grouped as amino, peptide, and polyose by the analysis. Both of the materials could hardly behydrolyzed in PBS solution without the enzymes. The four different enzymes had different surface morphologies under the examination of SEM. Conclusion The antigen-extracted meniscus is enzymolyzed more slowly than the fresh meniscus in vitro, and the result can be used as a guideline to the further research.
Objective To examine the research status and predict trends in ME research findings from 1997-2023 on a global scale. Methods Web of Science Core Collection database was searched for original articles on ME published between 1997 and 2023, and then analyzed using CiteSpace, VOSviewer and the Online Analysis Platform of Literature Metrology to map scientific knowledge. Results A total of 748 articles were eventually included. The number of ME publications increased year by year, with the USA being the most productive country. Osteoarthritis, MRI, medial meniscus posterior root repair, biomechanical evaluation, lateral meniscus allograft transplantation, radiographic joint space narrowing are the high frequency keywords in co-occurrence cluster analysis and cocited reference cluster analysis. Medial meniscus posterior root tear and lateral meniscus allograft transplantation are current and evolving research hotspots in citation burst detection analysis. Conclusions The understanding of ME has been improved significantly during the past decades. Current research focuses on optimizing surgical repair methods and obtaining long-term follow-up outcomes for medial meniscal posterior root repair and developing methods to reduce ME after lateral meniscal allograft, as well as they are the highlights of future research on ME.
OBJECTIVE To investigate the effect of meniscus suture on meniscus healing which included healing time and healing pattern. METHODS Fourty healthy rabbits were adopted in this study. The model of meniscus injury was made by a longitudinal incision at the medial meniscus of the left knee. The rabbits were divided into two groups, the experimental group was treated by meniscus suture and the control group was unsutured. After operation, the meniscus samples were collected periodically and observed by gross, light and electronic microscope to analysis the meniscus healing. RESULTS The injured meniscus was healed gradually and completely at the sixth week in the experimental groups. More fibroblasts and less fibrocartilage cells could be observed in the healed meniscus. Oppositely, there was no meniscus healing in the control group and the edge of injured meniscus was sealed by epithelioid cells. CONCLUSION The meniscus suture can accelerate the healing process of meniscus injury. Besides, early suture make the injured meniscus correctly positioned to ensure the normal healing process.
To design a new suit of instruments for meniscal suture with tondon, and then authenticate their feasibil ity and the therapeutic effect of the new technique. Methods Instruments were developed, including new ones and others which was improved according to the current instruments. From October 2005 to December 2006, 45 patients with meniscal injury were treated by meniscal suture with tendon. There were 29 males and 16 females, aged 17-40 years (mean 28 years). Injury was caused by sports in 33 cases, by traffic accident in 5 cases, by fall ing in 3 case and others in 4 cases. The disease course was 3 days to 6 months (mean 2 months). There were 23 cases accompanying with anterior cruciate l igament injury and 6 cases accompanying with posterior cruciate l igament injury. E-MRI showed 2 cases of degree II and 43 cases of degree III. Arthroscope showed that injury was at medial meniscus in 39 cases and at lateral meniscus in 6 cases. The pre-operationalLysholm score was 53.0 ± 10.3. Autogeneic or xenogenic tendon was made into suture l ine guided by stitch at the two ends. Thetherapeutic effect of the new technique was authenticated by cl inical results, including the change of symptoms and phy sical signs, and by comparing the pre-operational Lysholm score with the post one. Results Nineteen pieces of instruments weredeveloped. All the operation were successful, with no harm to nerves and vessels. The follow-up was 6 months to 24 mo nths (mean15 months). At the last follow-up, all the symptoms disappeared, including pain, swell ing and locking, etc. The Lysholm sc oreafter 6 months of operation was 87.8 ± 9.2, showing statistically significant difference when compared with per-operati on ( P lt; 0.01). Conclusion It is feasible to suture injured menisci with the new instruments and technique. It is an effective way to repair menisci with tendon according to the short-term results.
Objective To compare biological characteristics between articular chondrocyte and meniscal fibrochondrocyte cultured in vitro andto investigate the possibility of using cultured cartilage as a substitute for meniscus.Methods Chondrocytes isolated from articular cartilage and meniscus of rabbits aged 3 weeks were respectively passaged in monolayer and cultured in centrifuge tube. Cartilages cultured in centrifuge tube and meniscus of rabbit aged 6 weeks were detected by histological examination and transmission electron microscopy. Growth curves of articular chondrocytes and meniscalfibrochondrocytes were compared; meanwhile, cell cycles of articular chondrocytes and meniscal fibrochondrocytes in passage 2and 4 were separately measured by flow cytometry.Results Articular chondrocytes in passage 4 were dedifferentiated. Articular chondrocytes formed cartilage 2 weeks after cultivation in centrifuge tube, but meniscal fibrochondrocytes could not generate cartilage. The differences in ultrastructure and histology obviously existed between cultured cartilage and meniscus; moreover, apoptosis of chondrocytes appeared in cultured cartilage. Proportion of subdiploid cells in articular chondrocytes passage 2 and 4 was markedly higher than that in passage 2 and 4 fibrochondrocytes(Plt;0.05). Conclusion Meniscal fibrochondrocytes can not form cartilage after cultivationin centrifuge tube, while cartilage cultured in centrifuge tube from articular chondrocytes can not be used as graft material for meniscus. Articular cartilage ismarkedly different from meniscus.
ObjectiveTo explore the application value and operation skills of arthroscopic automatic reverse guide wire passer (hereinafter referred to as wire passer) in the posterior meniscus root reconstruction. Methods Between August 2015 and December 2020, 36 patients with posterior meniscus root tears were admitted. There were 16 males and 20 females, with an average age of 46 years (range, 26-66 years). There were 15 cases of sports injury and 21 cases of degenerative injury. The disease duration was 3-180 days, with a median of 28 days. The posterior root of the medial meniscus was injured in 29 cases, and the posterior root of the lateral meniscus was injured in 7 cases. The preoperative Lysholm score of the knee joint was 47.6±3.9, and the International Knee Score Committee (IKDC) score was 39.3±3.0. The meniscus was sutured by using wire passer under arthroscopy. During operation, the suture operation was evaluated according to the self-defined evaluation standard. Lysholm score and IKDC score were used to evaluate knee joint function. Results All meniscuses were sutured successfully by using wire passer. The operation time of suture was 5-15 minutes, with an average of 10 minutes. According to the self-defined evaluation standard, the suture operation was scored as 0-10, with an average of 5. After operation, except for 2 cases of incision fat liquefaction, the incisions of the other patients healed by first intention. All patients were followed up 1-3 years, with an average of 1.5 years. The Lysholm score was 88.2±2.1 and the IKDC score was 51.7±2.3 at 1 year after operation, showing significant difference when compared with preoperative ones (P<0.001). Fifteen cases underwent MRI re-examination, the results showed that the continuity and integrity of the posterior root had been restored. Conclusion Under arthroscopy, the wire passer for the posterior meniscus root reconstruction has the advantages of simple operation, reliable suture quality, and shorter operation time.
ObjectiveTo summarize the mid-term effectiveness of arthroscopic anterior cruciate ligament (ACL) reconstruction combined with meniscus allograft transplantation.MethodsA clinical data of 21 patients treated with arthroscopic ACL reconstruction and meniscus allograft transplantation and followed up more than 5 years between February 2007 and December 2014 was retrospectively analyzed. There were 12 males and 9 females, aged from 18 to 45 years, with an average age of 23.5 years. The cause of injury was sport sprain in 15 cases, falling in 4 cases, and traffic accident in 2 cases. The time from injury to operation ranged from 2 to 36 months, with an average of 12 months. Among them, 15 patients underwent previous meniscectomy, with an average interval of 1.6 years (range, 3 months to 6.5 years). All patients were primary ACL reconstruction. Preoperative anterior drawer test, Lachman test, and pivot shift test were positive. Lysholm score was 43.6±10.2. International Knee Documentation Committee (IKDC) score was 60.50±14.06. Of the 21 patients, 10 were gradeⅠ-Ⅱcartilage injuries and 11 were grade Ⅲ cartilage injuries according to MRI. ResultsAll patients were followed up 5.1-7.8 years, with an average of 5.5 years. There were 2 cases of numbness of lower extremity, 3 cases of slight exudation of incision, 2 cases of articular movement bounce, 5 cases of mild joint swelling and pain after exercise. At last follow-up, Lachman tests were negative in 18 cases and positive in 3 cases; anterior drawer tests were negative in 19 cases and positive in 2 cases; pivot shift tests were negative in all cases. Lysholm score was 84.5±16.5 and IKDC score was 85.25±4.60, which were significantly higher than those before operation (P<0.01). The flexion and extension of the affected knee joint were (128±13) and (3±7)°, respectively, which were smaller than those of the healthy knee joint [(133±15), (0±5)°] (P<0.01). The results of KT-1000 test showed that when knee flexion was 30 and 90°, tibial anterior displacement of affected side [(2.35±1.20), (1.60±1.15) mm] were not significantly different from those of healthy side [(1.20±1.10), (1.10±1.03) mm] (P>0.01). MRI showed that the ACL graft was in normal position and meniscus survived well. Cartilage injuries were gradeⅠ-Ⅱ in 18 cases and grade Ⅲ in 3 cases. ConclusionFor patients with severe meniscus injury and ACL rupture, ACL reconstruction combined with meniscus allograft transplantation can restore the stability of the joint, recover the meniscus function which is conducive to the protection of articular cartilage and obtain satisfactory mid-term effectiveness.
Objective To investigate the result of the arthroscopicrepair of the meniscus tears with the absorbable sutures. Methods From June 1998 to May2003，the meniscus tears in 110 patients (78 males, 32 females; aged 1466 years, averaged 27.5 years) were repaired with absorbable sutures under an arthroscope. In the patients, there were 93 vertical split injuries, 12 transverse split injuries, and 5 hidden split injuries. There were 78 tears in the lateral margin of the meniscus, 23 tears in the anterior angle of the meniscus, and 9 tears in the posterior angle of the meniscus. Ninetyone patients had 2 sutures, 13 patients had 4 sutures, 4 patients had 6 sutures, and 2 patients had 8 sutures. The rehabilitation program was performed in all the patients postoperatively, and the clinical outcome was observed. The Lysholm score was 57±12 preoperatively. Results Thefollow-up for an average of 26 months (range,12-67 months) showed that 3 patients had a light pain on exertion in the surgically-treated knee;1 patientunderwent an operation again for recurrence of the symptoms due to a failure in the healing of the meniscus tear, so a second arthroscopic operation was performed; and the other patients had a satisfactory result with an excellent knee function. The Lysholm score was 92±7 after operation. Conclusion The arthroscopic repair of the meniscustears has advantages of safety and reliability in the suturing and easier to perform. The repaired meniscus can play much better physiological and biomechanical functions, and will not limit the normal movement of the meniscus during the knee flexion after the sutures are absorbed.
Objective To elucidate the latest research progress and application of tissue engineered meniscus. Methods The literature concerning the advance in tissue engineered meniscus was extensively reviewed, then closely-related issues including seed cells, scaffolds, and bioreactors were analyzed. Results With more and more attention being paid to meniscus tissue engineering, different approaches and strategies for seed cells, scaffolds, and bioreactors have contributed to the generation of meniscal constructs, which are capable of restoring meniscal lesions to some extent, but translating successes in basic science research to clinical application is still limited. Conclusion More research for the optimal combination of the appropriate cell source, the scaffold type, and the proper physical and chemical factors for the stimulation of cells differentiation into tissue with optimal phenotypes in tissue engineered meniscus is still in needed, but the overall future looks promising.
Objective To investigate the injury mechanism, clinical characteristics, and treatments of Segond fracture and complications. Methods Fifteen patients suffering from Segond fracture were treated between January 2007 and December 2011. There were 10 males and 5 females, aged 16-50 years (mean, 31.8 years). Fracture was caused by traffic accident in 8 cases, by sports in 6 cases, and by bruise in 1 case. Before operation, the knee range of motion (ROM) was (36.60 ± 8.94)°; the Lysholm score was 32.27 ± 3.73; and the International Knee Documentation Committee (IKDC) score was 42.34 ± 4.97. The duration from injury to operation was 1-3 weeks with an average of 1.2 weeks. In 12 patients having associated anterior cruciate ligament (ACL) injury, arthroscopic reconstruction of ACL was performed with allogeneic anterior tibial tendon; in 2 patients having associated avulsion fracture of the intercondylar eminence of the tibia, arthroscopic fracture reduction and fixation with Orthocord wire were performed. In 8 patients having associated meniscus injury, meniscus suture and meniscectomy were performed in 3 and 5 patients, respectively. In 7 patients having associated collateral ligament injury, conservative treatment was given in 5 patients, and medial collateral ligament was repair in 2 patients. Results All incisions healed primarily without complications of infection and nerve or blood vessel injury. All the patient were followed up 12-16 months (mean, 14.3 months). At 12 months after operation, the results of anterior drawer test, Lachman test, and lateral stress test were all negative. The knee ROM was (129.27 ± 5.89)°, the IKDC score and Lysholm score were significantly increased to 89.45 ± 3.05 and 87.87 ± 4.12 at 12 months after operation; all showing significant differences when compared with preoperative values (P lt; 0.05). Conclusion Segond fracture is often combined with ACL, collateral ligament, and meniscus injuries, and the evidence of Segond fracture can bly suggests the knee injury. Personalized treatment should be chosen according to complications.