ObjectiveTo compare the strength difference between the interfacial screw and the interfacial screw combined with bone tunnel crossing technology to fix the tibial end of ligament during anterior cruciate ligament (ACL) reconstruction through the biomechanical test.MethodsTwenty fresh frozen pig tibia were randomly divided into two groups (n=10) to prepare ACL reconstruction models. The graft tendons in the experimental group were fixed with interfacial screw combined with bone tunnel crossing technology, and the graft tendons in the control group were fixed with interfacial screw. The two groups of specimens were fixed in the high-frequency dynamic mechanics test system M-3000, and the length change (displacement), ultimate load, and stiffness of graft tendons were measured through the reciprocating test and load-failure test.ResultsThe results of reciprocating test showed that the displacement of the experimental group was (3.06±0.58) mm, and that of the control group was (2.82±0.46) mm, and there was no significant difference between the two groups (t=0.641, P=0.529). The load-failure test results showed that the stiffness of the experimental group and the control group were (95.39±13.63) and (91.38±14.28) N/mm, respectively, with no significant difference (t=1.021, P=0.321). The ultimate load of the experimental group was (743.15±173.96) N, which was significantly higher than that of the control group (574.70±74.43) N (t=2.648, P=0.016).ConclusionIn ACL reconstruction, the fixation strength of tibial end with interface screw combined with bone tunnel crossing technology is obviously better than that of interface screw alone.
Objective To investigate the effect of Kartogenin (KGN) combined with adipose-derived stem cells (ADSCs) on tendon-bone healing after anterior cruciate ligament (ACL) reconstruction in rabbits. Methods After the primary ADSCs were cultured by passaging, the 3rd generation cells were cultured with 10 μmol/L KGN solution for 72 hours. The supernatant of KGN-ADSCs was harvested and mixed with fibrin glue at a ratio of 1∶1; the 3rd generation ADSCs were mixed with fibrin glue as a control. Eighty adult New Zealand white rabbits were taken and randomly divided into 4 groups: saline group (group A), ADSCs group (group B), KGN-ADSCs group (group C), and sham-operated group (group D). After the ACL reconstruction model was prepared in groups A-C, the saline, the mixture of ADSCs and fibrin glue, and the mixture of supernatant of KGN-ADSCs and fibrin glue were injected into the tendon-bone interface and tendon gap, respectively. ACL was only exposed without other treatment in group D. The general conditions of the animals were observed after operation. At 6 and 12 weeks, the tendon-bone interface tissues and ACL specimens were taken and the tendon-bone healing was observed by HE staining, c-Jun N-terminal kinase (JNK) immunohistochemical staining, and TUNEL apoptosis assay. The fibroblasts were counted, and the positive expression rate of JNK protein and apoptosis index (AI) were measured. At the same time point, the tensile strength test was performed to measure the maximum load and the maximum tensile distance to observe the biomechanical properties. Results Twenty-eight rabbits were excluded from the study due to incision infection or death, and finally 12, 12, 12, and 16 rabbits in groups A-D were included in the study, respectively. After operation, the tendon-bone interface of groups A and B healed poorly, while group C healed well. At 6 and 12 weeks, the number of fibroblasts and positive expression rate of JNK protein in group C were significantly higher than those of groups A, B, and D (P<0.05). Compared with 6 weeks, the number of fibroblasts gradually decreased and the positive expression rate of JNK protein and AI decreased in group C at 12 weeks after operation, with significant differences (P<0.05). Biomechanical tests showed that the maximum loads at 6 and 12 weeks after operation in group C were higher than in groups A and B, but lower than those in group D, while the maximum tensile distance results were opposite, but the differences between groups were significant (P<0.05). Conclusion After ACL reconstruction, local injection of a mixture of KGN-ADSCs and fibrin glue can promote the tendon-bone healing and enhance the mechanical strength and tensile resistance of the tendon-bone interface.
OBJECTIVE: To observe the strength of thigh muscles after reconstruction of anterior cruciate ligament by autogenous bone-patellar tendon-bone graft. METHODS: Twenty-three patients, 9 males and 14 females, were followed up one year after reconstruction of the anterior cruciate ligament with autogenous bone-patellar tendon-bone graft. Through arthroscope, no intra-articular derangement was found. The strengths of isometric and isotonic contractions of the quadri ceps and the hamstrings muscles of the affected and contralateral thighs were recorded. RESULTS: The donor side for autogenous bone-patellar tendon-bone graft showed significant decrease (P lt; 0.01), but no effect on that of the hamstrings muscle(P gt; 0.05). CONCLUSION: To reconstruct the anterior cruciate ligament, harvest of the bone-patellar tendon-bone graft as a reparative material may markedly lower the strength of the quadriceps femoris muscle.
ObjectiveTo summarize the prevention and treatment of iatrogenic medial collateral ligament (MCL) injuries in total knee arthroplasty (TKA).MethodsThe relevant literature about iatrogenic MCL injuries in TKA was summarized, and the symptoms, causes, preventions, and treatments were analyzed.ResultsPreventions on the iatrogenic MCL injuries in TKA is significantly promoted. With the occurrence of MCL injuries, the femoral avulsion can be fixed with the screw and washer or the suture anchors; the tibial avulsion can be treated with the suture anchors fixation, bone staples fixation, or conservative treatment; the mid-substance laceration can be repaired directly; the autologous quadriceps tendon, semitendinosus tendon, or artificial ligament can be used for the patients with poor tissue conditions or obvious residual gap between the ligament ends; the use of implant with greater constraint can be the last alternative method.ConclusionNo consensus has been reached to the management of iatrogenic MCL injuries in TKA. Different solutions and strategies can be integrated and adopted flexibly by surgeons according to the specific situation.
Objective To make a comparison for the change of maximum tensile intensity and stiffness of a whole implant that is placed into bone tunnel with various lengths tendon, by using beagle dog’s autogenous flexor tendons to reconstruct anterior cruciate l igament (ACL). Methods Sixty male beagle dogs were included in the experiment (weighting 13-16 kg). Three dogs were used for intact flexor tendon of both knees (normal control group), 3 dogs for the intact ACL andfemur-graft-tibia complex (auto control group) and 54 dogs (108 knees) for models of reconstructed ACL (6 experimentalgroups according to different lengths of tendon: 5, 9, 13, 17, 21 and 25 mm in the bone tunnel). The tensile intensity and stiffness were measured after 45, 90 and 180 days separately after operation. Results In the normal control group, the maximum tensile intensity of the intact flexor tendon was (564.15 ± 36.18) N, the stiffness was (59.89 ± 4.28) N/ mm. In the auto control group, the maximum tensile intensity of the intact ACL was (684.75 ± 48.10) N, the stiffness was (74.34 ± 6.99) N/ mm, all ruptured through the intra-articular portion of the graft. The maximum tensile intensity of femur-graft-tibia complex in the auto control group was (301.92 ± 15.04) N, the stiffness was (31.35 ± 1.97) N/mm. After 45 days of operation, all failure occurred at the tibial or femoral insertion site. After 90 days of operation, 24 of the breakpoints were scattered in tendon-bone junction, 12 (3 in 17 mm group, 5 in 21 mm group, 4 in 25 mm group) ruptured through the intra-articular portion. After 180 days of the operation, all breakpoints were distributed inside joint of the implant. The maximum tensile intensity and the stiffness were ber in 17, 21 and 25 mm groups than in 5, 9 and 13 mm groups after operation (P lt; 0.05). Conclusion Tendon with 17 mm length, which will be implanted into bone tunnel, is an appl icable index, in reconstruction of ACL by autogenous tendons.
Objective To review research progress on femoral attachment positioning during medial patellofemoral ligament (MPFL) reconstruction, so as to provide a reference for accurate positioning in clinic. Methods The literature at home and abroad on femoral attachment positioning during MPFL reconstruction was extensively reviewed and summarized. Results MPFL is the main ligament that restricts patellar outward migration, so MPFL reconstruction is the main treatment for patellar dislocation, but the accuracy of intraoperative femoral attachment positioning will significantly affect the effectiveness. At present, there are three main methods for femoral attachment positioning in MPFL reconstruction, including imaging positioning, bony landmark positioning, and new technology. Among them, the main imaging positioning method is the “Schöttle point” method, but it has high requirements for fluoroscopic positioning, and can only be accurately positioned under standard lateral fluoroscopy of the femur. The bony landmark positioning method mainly locates the femoral attachment by touching or dissecting the bony landmarks such as adductor tubercles and medial epicondyle of femur, but its disadvantages are that the positioning is not accurate enough, the intraoperative visual field exposure requirements are high, and a large incision is required. In order to avoid the problem that the simple bony landmark positioning method, in recent years, the combination of bony landmarks combined with arthroscopy, three-dimensional (3D) printing technology, and robot-assisted positioning methods have begun to be used in clinical practice. New technology localization methods have shown good results by preparing guides before operation, planning positioning paths in advance, or directly using robots to assist positioning during operation. Conclusion The accurate positioning of the femoral attachment in MPFL reconstruction is crucial, and the method of accurate and rapid intraoperative determination needs to be further improved and optimized. In the future, it is expected that the combination of computer image recognition correction technology and intraoperative position assistance will solve this problem.
Objective To investigate whether anterior cruciate l igament (ACL) reconstruction with the remnants and the remaining bundle preservation is beneficial for the revascularization of the graft or not. Methods Animal models of the ACL reconstruction in 18 healthy New Zealand White rabbits (2-3 months old) were made using about 2.5 cm long extensordigitorum longus tendon and randomly divided into three groups (n=6): remnants debridement group (group A), remnantspreservation group (group B) and remaining bundle preservation group (group C). The histological examination was made after 2, 4 and 8 weeks of operation. The intravascular injection of ink was used to observe the revascularization of the graft. The specimens were stained with HE method to observe the histological changes of the graft. Results All the animals were in good condition and had good knee functions in the observation period. There was no new vessel in groups A and B at 2 and 4 weeks postoperatively. And new vessels were observed in the synovium of the graft in group C. The areas of the vessels in group C were (505 ± 27) pixels at 2 weeks and (624 ± 23) pixels at 4 weeks. At 8 weeks postoperatively new vessels were observed in all the three groups. The new vessel areas of groups A, B and C were (674 ± 65), (836 ± 76) and (1 219 ± 146) pixels, respectively. The vessel areas of group C were significantly bigger than those of groups A and B (P lt; 0.05). The vessel area of group B was significantly bigger than that of group A (P lt; 0.05). The fibroblast amount in group B was significantly more than that in group A at 2 and 4 weeks postoperatively (P lt; 0.05). But there was no significant difference between them at 8 weeks postoperatively (P gt; 0.05). The fibroblast amount of group C was significantly more than that of group A (P lt; 0.05) at each observation time postoperatively. At 2 and 4 weeks postoperatively, the fibroblast amount of group C was significantly more than that of group B (P lt; 0.05), but there was no significant difference between them at 8 weeks postoperatively (P gt; 0.05). Conclusion ACL reconstruction with remnants and remaining bundle preservation is beneficial for the early revascularization and fibroblasts growing of the graft. So the course of necrosis, regeneration and remodel ing of the graft is shortened.
Objective To review the studies about the tibial-graft fixation methods on anterior cruciate ligament (ACL) reconstruction, in order to provide clinical reference. MethodsThe literature about the tibial-graft fixation methods on ACL reconstruction at home and abroad was extensively reviewed, and the factors that affect the selection of fixation methods were summarized. Results The knee flexion angle, graft tension, and graft fixation device are mainly considered when the tibial-graft was fixed on ACL reconstruction. At present, the graft is mainly fixed at 0°/30° of knee flexion. The study shows that the knee joint is more stable after fixed at 30°, while the incidence of knee extension limitation decrease after fixed at 0°. In terms of graft tension, a good effectiveness can be obtained when the tension level is close to 90 N or the knee flexion is 30° to recover the affected knee over-restrained 2 mm relative to the healthy knee. In terms of the graft device, the interference screw is still the most commonly used method of tibial-graft fixation, with the development of all-inside ACL reconstruction in recent years, the cortical button fixation may become the mainstream. Conclusion Arthroscopic reconstruction is the main treatment of ACL rupture at present. However, there is no optimal fixation method for the tibial-graft, the advantages and disadvantages of each fixation methods need to be further studied.
ObjectiveTo compare the effectiveness of all-arthroscopic technique and modified open Broström technique in repair of anterior talofibular ligament (ATFL) for lateral instability of the ankle (LIA).MethodsA retrospective analysis was made on 65 patients who underwent ATFL repair with anchors for LIA between January 2014 and January 2017. The ATFL was repaired by all-arthroscopic technique in 35 patients (arthroscopic group) and modified open Broström technique in 30 patients (open group). There was no significant difference in age, gender, the side of injured ankle, the time from injury to operation, and preoperative anterior displacement of talus, tilt angle of talus, the Karlsson Ankle Functional (KAF) score, American Orthopaedic Foot and Ankle Society (AOFAS) score, and Japanese Society for Surgery of the foot ankle-hindfoot (JSSF) scale score between the two groups (P>0.05). The operation time, the intraoperative bleeding volume, and the length of time for surgery recovery were recorded. The anterior displacement of talus, the tilt angle of talus, KAF score, AOFAS score, and JSSF scale score were evaluated at 2 weeks, 3 months, and the last follow-up.ResultsAll patients were followed up 24-30 months, with an average of 26 months. The operation time, intraoperative bleeding volume, and the length of time for surgery recovery of arthroscopic group were superior to open group (P<0.05). There were 2 cases of temporary ankle and dorsum numbness and 1 case of thread reaction in arthroscopic group; and there were 2 cases of temporary ankle and dorsum numbness and 2 cases of thread reaction in open group. The AOFAS score, KAF score, and JSSF scale score in arthroscopic group were significantly higher than those in open group (P<0.05) at 2 weeks after operation; there was no significant difference between the two groups at 3 months and the last follow-up (P>0.05). There was no significant difference in the anterior displacement of talus and the tilt angle of talus between the two groups at 2 weeks, 3 months, and last follow-up (P>0.05).ConclusionCompared with the modified open Broström technique, the all-arthroscopic technique, as a minimally invasive technique, can achieve the same effectiveness, and has the advantages of shorter operation time, less intraoperative bleeding, and less pain in the early stage.
Fourteen patients with anterior cruciate ligament (ACL) injuries were treated with carbon fiber—superficial fascia complex and were followed up with an average of 25 months. The overall results in our series were excellent or good. The patients had stable knees and few had some subjective complaints. The influence on the knee function after injury of ACL was discussed.