To fix the ligaments, tendons or other transplantation materials by passing through bone channels was commonly used and a relialde method in the reconstruction of joint stability. Usually an additional incision was necessary on the side of the outlet of the bone channel, that the screws, plates or U-shaped staple could be applied. An instrument was designed that the steel miniplate could be fixed to the bone by noninvasive method. This technique was applied in 20 cases in which anterior cruciate ligament in 14, posterior cruciate ligament in 4, and collateral ligaments in 2 with carbon fibers. The result was successful in all patients. It was shown that it gave simple manipulation, reliable fixation and no need to have an additional incision, and it could lessen patients’ suffering and lead to satisfactory clinical result.
ObjectiveTo solve the fixation problem between ligament grafts and host bones in ligament reconstruction surgery by using ligament-bone composite scaffolds to repair the ligaments, to explore the fabrication method for ligament-bone composite scaffolds based on three-dimensional (3-D) printing technique, and to investigate their mechanical and biological properties in animal experiments. MethodsThe model of bone scaffolds was designed using CAD software, and the corresponding negative mould was created by boolean operation. 3-D printing techinique was employed to fabricate resin mold. Ceramic bone scaffolds were obtained by casting the ceramic slurry in the resin mould and sintering the dried ceramics-resin composites. Ligament scaffolds were obtained by weaving degummed silk fibers, and then assembled with bone scaffolds and bone anchors. The resultant ligament-bone composite scaffolds were implanted into 10 porcine left anterior cruciate ligament rupture models at the age of 4 months. Mechanical testing and histological examination were performed at 3 months postoperatively, and natural anterior cruciate ligaments of the right sides served as control. ResultsBiomechanical testing showed that the natural anterior cruciate ligament of control group can withstand maximum tensile force of (1 384±181) N and dynamic creep of (0.74±0.21) mm, while the regenerated ligament-bone scaffolds of experimental group can withstand maximum tensile force of (370±103) N and dynamic creep of (1.48±0.49) mm, showing significant differences (t=11.617,P=0.000; t=-2.991,P=0.020). In experimental group, histological examination showed that new bone formed in bone scaffolds. A hierarchical transition structure regenerated between ligament-bone scaffolds and the host bones, which was similar to the structural organizations of natural ligament-bone interface. ConclusionLigament-bone composite scaffolds based on 3-D printing technique facilitates the regeneration of biomimetic ligament-bone interface. It is expected to achieve physical fixation between ligament grafts and host bone.
The surgical installation accuracy of the components in unicompartmental knee arthroplasty (UKA) is an important factor affecting the joint function and the implant life. Taking the ratio of the medial-lateral position of the femoral component relative to the tibial insert (a/A) as a parameter, and considering nine installation conditions of the femoral component, this study established the musculoskeletal multibody dynamics models of UKA to simulate the patients’ walking gait, and investigated the influences of the medial-lateral installation positions of the femoral component in UKA on the contact force, joint motion and ligament force of the knee joint. The results showed that, with the increase of a/A ratio, the medial contact force of the UKA implant was decreased and the lateral contact force of the cartilage was increased; the varus rotation, external rotation and posterior translation of the knee joint were increased; and the anterior cruciate ligament force, posterior cruciate ligament force and medial collateral ligament force were decreased. The medial-lateral installation positions of the femoral component in UKA had little effect on knee flexion-extension movement and lateral collateral ligament force. When the a/A ratio was less than or equalled to 0.375, the femoral component collided with the tibia. In order to prevent the overload on the medial implant and lateral cartilage, the excessive ligament force, and the collision between the femoral component and the tibia, it is suggested that the a/A ratio should be controlled within the range of 0.427−0.688 when the femoral component is installed in UKA. This study provides a reference for the accurate installation of the femoral component in UKA.
ObjectiveTo investigate the effect of transforming growth factorβ1 (TGF-β1) and basic fibroblast growth factor 1 (bFGF-1) on the cellular activities, prol iferation, and expressions of ligament-specific mRNA and proteins in bone marrow mesenchymal stem cells (BMSCs) and ligament fibroblasts (LFs) after directly co-cultured. MethodsBMSCs from 3-month-old Sprague Dawley rats were isolated and cultured using intensity gradient centrifugation. LFs were isolated using collagenase. The cells at passage 3 were divided into 6 groups: non-induced BMSCs group (group A), non-induced LFs group (group B), non-induced co-cultured BMSCs and LFs group (group C), induced BMSCs group (group D), induced LFs group (group E), and induced co-cultured BMSCs and LFs group (group F). The cellular activities and prol iferation were examined by inverted contrast microscope and MTT; the concentrations of collagen type Ⅰ and type Ⅲ were determined by ELISA; and mRNA expressions of collagen types I andⅢ, fibronectin, tenascin C, and matrix metalloproteinase 2 (MMP-2) were measured by real-time fluorescent quantitative PCR. ResultsA single cell layer formed in the co-cultured cells under inverted contrast microscope. Group F had fastest cell fusion ( > 90%). The MTT result indicated that group F showed the highest absorbance (A) value, followed by group D, and group B showed the lowest A value at 9 days after culture, showing significant difference (P < 0.05). Moreover, the result of ELISA showed that group F had the highest concentration of collagen type Ⅰ and type Ⅲ (P < 0.05); the concentration of collagen type Ⅲ in group E was significantly higher than that in group D (P < 0.05), but no significant difference was found in the concentration of collagen type Ⅰ between 2 groups (P > 0.05). The ratios of collagen type Ⅰ to type Ⅲ were 1.17, 1.19, 1.10, 1.25, 1.17, and 1.18 in groups A-F; group D was higher than the other groups. The real-time fluorescent quantitative PCR results revealed that the mRNA expressions of collagen type Ⅰ and type Ⅲ and fibronectin were highest in group F; the expression of tenascin C was highest in group D; the expression of MMP-2 was highest in group E; and all differencs were significant (P < 0.05). ConclusionDirectly co-cultured BMSCs and LFs induced by TGF-β1 and bFGF-1 have higher cellular activities, proliferation, and expressions of ligament-specific mRNA and protein, which can be used as a potential source for ligament tissue engineering.
Objective To introduce the research advance of the ligament injury and ligament healing.Methods Recent original articlesrelated to such aspects of ligament were reviewed extensively.Results The ligament properties would be influenced when the situations of the biochemistry and biomechanics had changed. Injuries to ligaments induce a healing response that is characterized by scar formation. Graft could not recovery the ultrastructure, anatomy and biomechanics of the normal ligament.Conclusion The healing ligament is weaker than normal one, and the graft could not reconstruct normal ligament at present.
OBJECTIVE: To observe the effects of hyaluronic acid (HA) and basic fibroblast growth factor (bFGF) on the proliferation of the cells from medial collateral ligament (MCL) and anterior cruciate ligament (ACL) cells. METHODS: The MCL cells and ACL cells of mature New Zealand white rabbit were cultured, while HA, bFGF or HA and bFGF were added to the cell culture media, the cellular proliferation was assayed by MTT method. RESULTS: HA only had no effect on the preoliferation of ACL cells, but had a small stimulatory effect on the proliferation of MCL cells. The addition of 1 ng/ml bFGF enhanced the proliferation of both MCL and ACL cells significantly, and this enhancement was maximal in the concentration of 50 ng/ml. However, the enhancement of proliferation of MCL and ACL cells could be achieved when the combination of HA in concentration of 100 micrograms/ml and bFGF in concentration of 100 ng/ml. CONCLUSION: It is evident that bFGF can enhance the proliferation of the ligament cells. HA can maintain the normal growth of ACL cells with no effect on the proliferation of the cells, while HA has a small stimulatory effect on the proliferation of MCL cells. However, when bFGF is coordinated with HA, more improvement of cellular proliferation can be achieved. HA can be used as a potential carrier for bFGF to enhance the healing of ligamentous tissue injuries.
【Abstract】 Objective To investigate the effect of the volar capsular l igament complex on stabil ity of the wrist jointand to provide basic biomechanical theoretical criteria for cl inic appl ication of the external fixator. Methods Nine upperl imbs specimens (left 6, right 3) were taken from fresh adult cadavers to make wrist joint-bone capsular l igament complex specimens. Firstly, soft tissues of forearms and hands were resected and capsular membranes and l igaments were reserved to make the bone-articular l igament complex (normal specimen). Secondly, the volar capsular l igament complex was cut off from radial malleolus to ulnar malleolus (impaired specimen). Thirdly, the impaired volar capsular l igament complex was interruptedly sutured by the use of 4# suture silk (repaired specimen). To simulate cl inical operation with external fixator, the biomechanical test was done according to the sequence (normal, impaired, repaired, repaired and fixed, impaired and fixed). Statistical significance was analyzed through selected loads at the three different shifts (1.5, 2.0, 2.5 cm). Results According to the sequence (normal, impaired, repaired, repaired and fixed, impaired and fixed), when the shift was 1.5 cm, the different respective loads were (60.74 ± 20.60), (35.23 ± 13.88), (44.36 ± 20.78), (168.40 ± 29.21) and (139.00 ± 33.18) N, respectively. When the shift was 2.0 cm, the different loads were (138.46 ± 12.93), (87.17 ± 24.22), (97.52 ± 23.29), (289.00 ± 54.29) and (257.98 ± 55.74) N, respectively. When the shift was 2.5 cm, the different loads were (312.87 ± 37.15), (198.16 ± 37.14), (225.66 ± 30.96), (543.15 ± 74.33) and (450.35 ± 29.38) N, respectively. There was no statistically significant difference between the impaired and repaired specimens (P gt; 0.05). Similarly, there was statistically significant difference among the rest specimens (P lt; 0.05). The same statistical results were obtained when the two different shifts were compared. There was statistically significant difference at the three different shifts for the same specimen (P lt; 0.05). Conclusion Volar capsular l igament complex is an important anatomic structure to keep stabil ity of the wrist joint. The carpal instabil ity arises out of the injured complex. Repairing the injured complex only can not immediately restore stabil ity of the wrist joint. The external fixator can effectively help to diminish the relative shift of the impaired capsular l igament complex, to reduce the load of the repaired complex and to protect the complex accordingly. The device plays an important role in maintaining stabil ity of the wrist joint.
Objective To review the research and del ivery methods of growth factors in tendon injuries, and to point out the problems at present as well as to predict the trend of development in this field. Methods Domestic and international l iterature concerning growth factors to enhance tendon and l igament heal ing in recent years was extensively reviewed and thoroughly analyzed. Results Cell growth factor could promote tendon heal ing, improve the mechanical properties as well as reduce the adhesion postoperatively. The use of transgenic technology mediating cell factors to promote tendon repair shows its advantages in many ways. Conclusion The growth factors play a vital role in tendon heal ing. Reasonable treatment of growth factors through direct appl ication or gene transfer techniques is of great value for the heal ing process.
Objective To investigate the method and curative effect of malposed-suture hanging and fastening method of double-lariat lock catch knot in repairing origin of medial collateral l igament (MCL) rupture. Methods From February 2008 to February 2009, 36 patients with acute MCL rupture were treated with malposed-suture hanging and fastening method of double-lariat lock catch knot. There were 21 males and 15 females with an average age of 40 years (range, 17-58 years),including 19 left knees and 17 right knees. Repture was caused by traffic accident in 5 cases, by fall ing in 11 cases, by kicking in 3 cases, by crush in 4 cases, and by sprain in 13 cases. The X-ray films of double knees at stress state showed the medial joint space of affected knee joint increased 6.5-13.5 mm (11.2 mm on average) when compared with that of normal knee joint. The time from injury to operation was 36 hours to 8 days (3.5 days on average). Results All wounds healed by first intention. Thirty-one cases were followed up 12-20 months (15 months on average). No compl ication of wound infection, deep venous thrombosis, and l igament rerupture occurred. The medial joint space of affected knee joint increased 1.5-5.6 mm (3.5 mm on average) when compared with that of normal knee joint. According to Lysholm assessment standard, the results were excellent in 20 cases and good in 11 cases, the excellent and good rate was 100%. Conclusion Repair of origin of MCL with malposedsuture hanging and fastening method of double-lariat lock catch knot has advantages of less injury, rel iable fixation, and rapid recovery of knee stabil ity.
ObjectiveTo summarize the current status and progress of the treatment of chronic lateral ankle instability (CLAI). MethodsThe literature about the anatomical repair of CLAI at home and abroad was reviewed and summarized. ResultsBroström and its modified operations are the most common surgical treatment of CLAI. The operations showed satisfactory clinical outcomes in the short-, medium-, and long-term follow-up and low complication rate. Suture anchor technique and arthroscopic techniques are gradually used in Broström and its modified operations with satisfactory short-term effectiveness, but long-term effectiveness needs further observation because of the limitation of the short clinical application time. ConclusionBroström and its modified operations are effective, convenient, and safe to treat CLAI. Based on the researches of biomechanics and dynamic anatomy, the more personalized design of the rehabilitation program is the further research direction.