Ligament augmentation reconstruction system artificial ligaments in patellar tendon reconstruction-a chronic patellar tendon rupture after multiple operations: A case report

BACKGROUND Patellar tendon rupture is a rare disease,and reports regarding patellar tendon reconstruction with ligament augmentation reconstruction system(LARS)ligaments are limited,with only three reports available in the literature.LARS ligaments are made of polyethylene terephthalate and have been certified as a more favorable option than other tendon transplants.To our knowledge,this is the first report of patellar tendon reconstruction with LARS for suture fixation due to poor quality of the tendon after multiple operations to enable early mobilization and quick rehabilitation.CASE SUMMARY A 65-year-old woman had limited ability in extending her leg and an inability to perform a straight leg raise after multiple operations due to patella fracture.The patient underwent patellar tendon reconstruction with LARS artificial ligaments.After 12 mo of follow-up,the patient was able to perform a straight leg raise,and the incision healed well without complications.The Lysholmscore was 95 and the range of motion of the knee was 0-130°.CONCLUSION This study revealed that patellar tendon reconstruction with LARS artificial ligaments is possible in a patient with a patellar tendon rupture who required rapid postoperative recovery.

A new method of anterior talofibular ligament reconstruction:Arthroscopically artificial ligament reconstruction with tensional remnant-repair

Purpose:To investigate the clinical effects of arthroscopically artificial ligament reconstruction with tensional remnant-repair in patients who are obese,and/or with demand for highly intensive sports,and/or with poor-quality ligament remnants.Methods:A retrospective case series study was performed on patients treated by arthroscopically anterior talofibular ligament(ATFL)reconstruction with tensional remnant repair technique from January 2019 to August 2021.General data,including demographics,surgical time,and postoperative adverse events,were recorded.The American Orthopaedic Foot and Ankle Society score(AOFAS),foot and ankle ability measure(FAAM),visual analog scale(VAS),and anterior talar translation were measured preoperatively and at 6 weeks,3 months,and 2 years postoperatively.Ultrasonography examination was performed preoperatively and 2 years postoperatively to evaluate the ATFL.Data were analyzed using SPSS 19.0.F test was used to analyze the pre-and postoperative VAS,FAAM,and AOFAS scores.The significance was set at p<0.05.Results:There were 20 males and 10 females among the patients with a mean age of(30.71±5.81)years.The average surgical time was(40.21±8.59)min.No adverse events were observed after surgery.At 2 years postoperatively,the anterior talar translation test showed grade 0 laxity in all patients.VAS score significantly decreased from preoperatively to 6 weeks,3 months,and 2 years postoperatively(p<0.001).Improvement of FAAM score and the AOFAS score from preoperatively to 6 weeks,3 months,and 2 years postoperatively was statistically significant(p<0.001).At 3 months postoperatively,most patients(23/30)could return to their pre-injured activities of daily living status.At 2 years postoperatively,all patients were able to return to their pre-injured activities of daily living status,and almost every patient(18/19)who expected highly intensive sports returned to sports with only 1 obese patient failing to achieve the goal.The ultrasonography examination at 2 years postoperatively showed that there was a linear band structure of soft tissue on the tension-rich fiber tape image from the fibular to the talar attachment sits of ATFL.Conclusion:The novel arthroscopically artificial ligament reconstruction with tensional remnant-repair technique for ATFL achieved satisfactory clinical outcomes in the short and medium term after operation,and allowed early return to pre-injured activities,which could be a reliable option for patients with chronic lateral ankle instability.

A Hierarchical Helical Carbon Nanotube Fiber Artificial Ligament

For the optimal functional recovery of force-transmitting connective tissues,obtaining grafts that are mechanically robust and integrating them with host bone effectively to tolerate high loads during violent joint motions is both crucial and challenging.Recent research proposes that a hierarchical helical carbon nanotube fiber,which has the considerably high mechanical strength,and can integrate with the host bone and restore movement in animals,is a very promising artificial ligament.The above research marks a significant development in artificial ligament via the innovative utilization of hierarchical helical carbon nanotube fiber.

Black tantalic oxide submicro-particles coating on PEEK fibers woven into fabrics as artificial ligaments with photothermal antibacterial effect and osteogenic activity for promoting ligament-bone healing

Design of artificial ligaments possessing both osteogenic activity and antibacterial effect that promotes ligament-bone healing and prevents bacterial infection in bone tunnels for anterior cruciate ligament(ACL)reconstruction remains a significant challenge.In this study,black tantalic oxide(BTO)submicro-particles with oxygen vacancies and structure defects were fabricated by using traditional white tan-talic oxide(WTO)through magnesium thermal reduction(MTR)method,and BTO was coated on polyetheretherketone(PEEK)fibers(PKF),which were woven into fabrics(PBT)as artificial ligaments.PBT with BTO coating exhibited excellent photothermal performance,which possessed not only antibac-terial effects in vitro but also anti-infective ability in vivo.PBT with optimized surface properties(e.g.,submicro-topography and hydrophilicity)not only significantly facilitated rat bone mesenchymal stem cells(BMSC)responses(e.g.,proliferation and osteogenic differentiation)in vitro but also stimulated new bone formation for ligament-bone healing in vivo.The presence of oxygen vacancies and structure de-fects in BTO did not change the surface properties and osteogenic activity of BPT while displaying an outstanding photothermal antibacterial effect.In summary,BPT with osteogenic activity and photother-mal antibacterial effect promoted bone regeneration and prevented bacterial infection,thereby promoting ligament-bone healing.Therefore,PBT would have tremendous potential as a novel artificial ligament for ACL reconstruction.

Cruciate ligament reconstruction using LARS artificial ligament under arthroscopy： 81 cases report

Background There are many different materials used for ligament reconstruction. Currently, autograft, allograft, and artificial ligaments are used in the reconstruction. The objective of this study was to explore the clinical result of cruciate ligament reconstruction under arthroscopy. Methods Eighty-one cases were reconstructed with the LARS ligament under arthroscopy, including 43 cases of anterior cruciate ligament （ACL） injury, 20 cases of posterior cruciate ligament （PCL） injury, and 18 cases of ACL combined with PCL injuries of the knee. The follow up period was 10 to 49 months. The International Knee Documentation Committee （IKDC） and Lysholm knee score scales were used for functional evaluation. We examined the anterior and posterior stability of the knee with KT-1000. Results According to the Lysholm knee function score scale, the average preoperative score of （44.6±1.4） increased to a postoperative score of （82.8±2.5） in the ACL group and from （46.6±2.3） to （80.8±2.0） in the PCL group. In the ACL combined with PCL injury group, the preoperative score increased from （45.2±1.2） to （85.5±2.3）. According to IKDC score standards, in ACL group we evaluated 19 cases as C and 24 cases as D, preoperatively, and postoperatively 27 cases as A, 14 cases as B and two cases as C. In the preoperative PCL group, we had 11 cases defined as C and nine cases as D that resolved to 12 cases as A, seven as B and one case of C in postoperative evaluation. In the ACL combined with PCL injury group we defined four cases as C and 14 as D during preoperative scoring. These patients had postoperative grades of six cases as A, 10 as B, and two cases as C. All of the results have statistical significance. Conclusions ACL, PCL, or combined ACL and PCL reconstruction using the LARS ligament under arthroscopy is a minimally invasive, safe and effective method to treat cruciate ligament injuries of the knee. Clinical results are satisfactory in the short term.

Characteristics of bone tunnel changes after anterior cruciate ligament reconstruction using Ligament Advanced Reinforcement System artificial ligament

Background There are different materials used for anterior cruciate ligament （ACL） reconstruction. It has been reported that both autologous grafts and allografts used in ACL reconstruction can cause bone tunnel enlargement. This study aimed to observe the characteristics of bone tunnel changes and possible causative factors following ACL reconstruction using Ligament Advanced Reinforcement System （LARS） artificial ligament. Methods Forty-three patients underwent ACL reconstruction using LARS artificial ligament and were followed up for 3 years. X-ray and CT examinations were performed at 1,3, 6, 12, 24, and 36 months after surgery, to measure the width of tibial and femoral tunnels. Knee function was evaluated according to the Lysholm scoring system. The anterior and posterior stability of the knee was measured using the KT-1000 arthrometer. Results According to the Peyrache grading method, grade 1 femoral bone tunnel enlargement was observed in three cases six months after surgery. No grade 2 or grade 3 bone tunnel enlargement was found. The bone tunnel enlargement in the three cases was close to the articular surface with an average tunnel enlargement of （2.5＋0.3） mm. Forty cases were evaluated as grade 0. The average tibial and femoral tunnel enlargements at the last follow-up were （0.8＋0.3） and （1.1＋0.3） mm, respectively. There was no statistically significant difference in bone tunnel width changes at different time points （P 〉0.05）. X-ray and CT measurements were consistent. Conclusions There was no marked bone tunnel enlargement immediately following ACL reconstruction using LARS artificial ligament. Such enlargement may, however, result from varying grafting factors involving the LARS artificial ligament or from different fixation methods.

Electrodeposition of calcium phosphate onto polyethylene terephthalate artificial ligament enhances graft-bone integration after anterior cruciate ligament reconstruction

It is a big challenge to develop a polyethylene terephthalate(PET)artificial ligament with excellent osteogenetic activity to enhance graft-bone integration for ligament reconstruction.Herein,we evaluated the effect of biomineralization(BM)and electrodeposition(ED)method for depositing calcium-phosphate(CaP)on the PET artificial ligament in vitro and in vivo.Scanning electron microscopy and energy-dispersive X-Ray spectrometer mapping analysis revealed that the ED-CaP had more uniform particles and element distribution(Ca,P and O),and thermogravimetric analysis showed there were more CaP on the PET/ED-CaP than the PET/BM-CaP scaffold.Moreover,the hydrophilicity of PET scaffolds was significantly improved after CaP deposition.In vitro study showed that CaP coating via BM or ED method could improve the attachment and proliferation of MC3T3-E1 cells,and ED-CaP coating significantly increased osteogenic differentiation of the cells,in which the Wnt/β-catenin signaling pathway might be involved.In addition,radiological,histological and immunohistochemical results of in vivo study in a rabbit anterior cruciate ligament(ACL)reconstruction model demonstrated that the PET/BM-CaP and PET/ED-CaP scaffolds significantly improved graft-bone integration process compared to the PET scaffold.More importantly,larger areas of new bone ingrowth and the formation of fibrocartilage tissue were observed at 12 weeks in the PET/ED-CaP group,and the biomechanical tests showed increased ultimate failure load and stiffness in PET/ED-CaP group compared to PET/BM-CaP and PET group.Therefore,ED of CaP is an effective strategy for the modification of PET artificial ligament and can enhance graft-bone integration both in vitro and in vivo.

Biocompatibility Evaluation of Polyethylene Terephthalate Artificial Ligament Coating Hydroxyapatite by Fibroblasts Cells in Vitro

Hydroxyapatite(HA) based materials have been widely used in the field of ligament tissue engineering in the past decades.It has been previously reported that HA can increase the penetration of marrow-derived mesenchymal stem cells(MSCs) and MSCs cells into scaffolds due to increased cell differentiation in biological media.Additionally,it was found that there are much difference between MSCs and anterior cruciate ligament (ACL) cells.For that reason,we mainly evaluate the biocompatibility of polyethylene terephthalate(PET) silk scaffold with fibroblasts cells in vitro.We cultured mouse fibroblasts cells on the substrate of PET fiber and PET-HA scaffold,respectively,and then observed the morphology by using scanning electron microscopy.Our data indicate that PET-HA scaffold has good biocompatibility with fibroblasts cells and can potentially be useful in enhancing the fibroblasts cell differentiation and proliferation.

The Effect of 58S Bioactive Glass Coating on Polyethylene Terephthalates in Graft-Bone Healing

In this study the effects of surface modification of Polyethylene Terephthalates （PET） fibers with 58S bioactive glasses on osteoblasts proliferation and osseointegration in the tibia-articular tendon-bone healing model were investigated. PET sheets were coated with 58S bioactive glass and uncoated PET sheets were used as a control. Scanning Electron Microscope （SEM） and X-ray photoelectron spectrometer were adopted to analyze the surface characteristics of the fibers. MT3T3-E 1 cells were cultured with the PET fibers and the MTT and ALP were tested at 1, 3, 5 days. Twenty-four skeletally mature male New Zealand white rabbits were randomly divided into two groups, the 58S-PET group and the PET group. Both groups underwent a surgical procedure to establish a tibia-articular tendon-bone healing model. Mechanical examinations and histological assays were taken to verify the coating effects in vivo. Results of both MTT and ALP tests show significant differences （P 〈 0.01） between the 58S-PET group and the PET group. At 6 weeks and 12 weeks, the max load-to-failure was significantly higher in the 58S-PET group. In the histological assays, distinct new bone formation was observed only in the 58S-PET group and stronger osseoin- tegration was seen in the 58S-PET group than that in the control group. The 58S-coating on PET could enhance the proliferation and activity of the osteoblasts and therefore promote the new bone formation and tendon-bone healing.