The application of artificial ligament products in anterior cruciate ligament (ACL) surgeries has gone through a long twisty way. In the 1970s, early artificial ligament products were initially used for ACL surgeries, which showed poor clinical efficacy and eventually ended up in failure. Over the last 20 years, there has been a growing number of ACL reconstruction with new artificial ligament products, including the Leeds-KeioTM, the LARSTM (Ligament Advanced Reinfocement System), and the Trevira HochfestTM. Among these new products, the LARSTM has been more commonly applied for ACL surgeries. Although these new artificial ligament products have good mechanical properties and show significant improvement of cumulative failure and complication rate, they still have limitations.
The shoulder joint is the most prone to dislocation in the whole body, and more than 95% of them are anterior dislocation. Improper treatment after the initial dislocation is easy to lead to recurrent anterior dislocation or anterior shoulder instability, and the outcomes following conservative treatment is poor. Anterior shoulder instability can damage the soft tissue structure and bone structure that maintain the stability of shoulder joint, among which bone structure is the most important factor affecting the stability of shoulder joint. Diagnosis should be combined with medical history, physical examination, and auxiliary examination. Currently, three-dimensional CT is the most commonly used auxiliary examination means. However, various bone defect measurement and preoperative evaluation methods based on three-dimensional CT and the glenoid track theory have their own advantages and disadvantages, and there is still a lack of gold standard. Currently, the mainstream treatment methods mainly include Bankart procedure, coracoid process transposition, glenoid reconstruction with free bone graft, Bankart combined with Remplissage procedure, and subscapular tendon binding tamponade, etc. Each of these procedures has its own advantages and disadvantages. For the diagnosis and treatment of anterior shoulder instability, there are still too many unknown, further research and exploration need to be studied.
ObjectiveTo explore the effect of silk fibroin/poly(L-lactic acid-co-e-caprolactone) [SF/P(LLA-CL)] nanofibrous scaffold on tendon-bone healing of rabbits.MethodsSF/P(LLA-CL) nanofibrous scaffold was fabricated by electrospinning methods. The morphology of the scaffold was observed by scanning electron microscope (SEM). Pre-osteoblasts MC3T3-E1 cells were seeded on the scaffold and cultured for 1, 3, and 5 days. Cell adhesion and proliferation were also observed by SEM. Meanwhile, twenty-four New Zealand white rabbits were randomly divided into the autogenous tendon group (control group) and the autogenous tendon wrapped with SF/P(LLA-CL) scaffold group (experimental group), with twelve rabbits in each group. An extra-articular model was established, the effect was evaluated by histological examination and mechanical testing.ResultsThe morphology of SF/P(LLA-CL) nanofibrous scaffold was random, with a diameter of (219.4±66.5) nm. SEM showed that the MC3T3-E1 cells seeded on the scaffold were in the normal shape, growing well, and proliferating with time course. The results of histological examination showed that inflammatory cells infltrated into the graft-host bone interface at 6 weeks after operation in both groups. Besides, the width of interface showed no significant difference between groups. At 12 weeks after operation, protruding new bone tissue could be observed at the interface in the experimental group, while scar tissue but no new bone tissue could be seen at the interface in the control group. Mechanical testing showed that there was no significant difference in the failure load and the stiffness between groups at 6 weeks after operation (P>0.05). The failure load and the stiffness in the experimental group were significantly higher than those in the control group at 12 weeks after operation (P<0.05).ConclusionThe SF/P(LLA-CL) nanofibrous scaffold has good cell biocompatibility and can effectively promote tendon-bone healing, thus providing new method for modifying graft for ACL reconstruction in the clinical practice.
Objective To make further exploration of the structure characteristics of anterolateral ligament (ALL) and provide clinical reference for diagnosis and treatment of ALL injury, especially for ALL reconstruction through anatomical study of ALL in a Chinese population. Methods Sixteen cadaveric knees, including 8 left knees and 8 right knees with sex ratio of 1∶1 and a mean age of 73.5 years (range, 57-84 years), were dissected to reveal the ALL through a standard approach. A qualitative and a quantitative characterizations of the ALL were performed. Results ALL was seen in 75.0% of the specimens, originating on the lateral femoral epicondyle, proximal and posterior to the lateral collateral ligament (LCL). It coursed on LCL or was parallel to LCL, anterodistally to its anterolateral tibial attachment approximately midway between the center of the Gerdy’s tubercle and the lateral margin of the fibular head. A strong connection was observed between the middle part of the ALL and the periphery of the meniscal body of the lateral meniscus. The distance between the center of the insertion and Gerdy’s tubercle was (23.9±3.3) mm; and the distance between the center of the insertion and the lateral margin of the fibular head was (23.8±4.0) mm. The ALL length at 0° and 60° flexion and neutral knee rotation were (44.8±5.1) mm and (47.8±5.5) mm respectively (t=14.071, P=0.000), and the ligament had its great extend at 60° of knee flexion and internal rotation. Furthermore, the ALL length at 0° and 60° flexion of males were both significantly higher than those of females (t=2.920, P=0.015; t=2.806, P=0.019), while other measurements differences were significant between males and females (P>0.05). Conclusion ALL is an independent and a non-isometric ligament located in the anterolateral area to the knee, of which the length is different between males and females. ALL plays a role in rotational stability of the knee, and should be put much emphasis in clinical practice.
Objective To review the basical research progress of porous tantalum in bone tissue engineering. Methods The related basical research in fabrication, cytobiology, and surface modification of porous tantalum was reviewed and analyzed. Results The outstanding physiochemical properties of porous tantalum granted its excellent performance in biocompatibility and osteointegration, as well as promoting cartilage and tendon tissue restoration. However, the clinical utilization of porous tantalum is somehow greatly limited by the complex and rigid commercial fabrication methods and extraordinary high cost. Along with the publication of novel fabrication and surface modification technology, the application of porous tantalum will be more extensive, the promotion in bone tissue regeneration will be more prominent. Conclusion Porous tantalum has advantage in bone defect restoration, and significant breakthrough technology is needed in fabrication methods and surface modification.
ObjectiveTo introduce the reduction concept of anteromedial cortical support in the treatment of intertrochanteric fracture, summarize the history, characteristics, biomechanics, and clinical applications, discuss the unsolved problems and prospect the future directions.MethodsRelevant domestic and foreign studies on cortical support reduction of intertrochanteric fracture in recent years were reviewed. Conclusions were drawn combined with clinical experience.ResultsThe positive cortical supportive reduction of intertrochanteric fracture, as a stable non-anatomical fracture reduction technique, has dual effects on mechanical buttress and biological bone healing. It does not increase the difficulty of doctors’ surgical procedure. For patients, it decreases the loss of femoral neck length, the loss of neck-shaft angle, the incidence rate of coxa vara, and maintains stable mechanical structure of the pelvis. It also shows a lower rate of instrument-related complications, and higher limb function scores. The mechanical stability of medial cortex apposition is more important than that of anterior cortex. For the best stability of the fracture, both sides should get positive support reduction pattern.ConclusionAnteromedial cortical support reduction can improve the postoperative stability of intertrochanteric fracture, enable better imaging and functional prognosis. As a kind of non-anatomic form of functional reduction, it can be used as a suboptimal choice secondary to anatomic reduction.
ObjectiveTo summarize the relationship between shoulder instability and superior labrum anterior posterior (SLAP) lesion. MethodsThe characteristics of shoulder instability and SLAP lesion were analyzed, and the relationship between them in pathogenesis, clinical symptoms, and biomechanics was discussed by referring to relevant domestic and foreign literature. ResultsShoulder instability and SLAP lesion can occur both spontaneously and respectively. SLAP lesion destroys the superior labrum integrity and the long head of biceps tendon (LHBT) insertion, causing excessive humeral head displacement against glenoid, and leading to shoulder instability. While chronic repetitive or acute high-energy traumatic shoulder instability can in turn aggravate SLAP lesion, resulting in expansion and increased degree of the original lesion. Conclusion SLAP lesion destroys mechanisms of shoulder stability, while shoulder instability causes tears of the upper labrum and the LHBT, showing a connection between shoulder instability and SLAP lesion. However, the existing evidence can only demonstrate that shoulder instability and SLAP lesion induce and promote the development of each other, instead of a necessary and sufficient condition. Therefore, the specific causal relationship between the two remains unknown and needs to be further studied.
Objective To compare the effectiveness of anatomical single-bundle (ASB) and over-the-top singlebundle (OSB) reconstruction of the anterior cruciate l igament (ACL). Methods Between January 2008 and June 2008, 64 patients with ACL injury underwent arthroscopic ACL reconstruction. ASB ACL reconstruction was performed in 28 cases (ASB group) and OSB ACL reconstruction in 36 cases (OSB group). There was no significant difference in gender, age, diseaseduration, International Knee Documentation Committee (IKDC) score, Lysholm score, and side-to-side difference between 2 groups (P gt; 0.05). Results All incisions healed by first intention; no infection or other compl ications occurred. All cases were followed up 20-24 months (mean, 21.5 months). There were significant differences in the IKDC score, Lysholm score, and the side-to-side difference between last follow-up and preoperation in 2 groups (P lt; 0.05), but there was no significant difference between 2 groups at last follow-up (P gt; 0.05). Significant differences were found in negative rate of the pivot shift test between last follow-up and preoperation in ASB group and between 2 groups at last follow-up (P lt; 0.05), but there was no significant difference between last follow-up and preoperation in OSB group (P gt; 0.05). Conclusion The effectiveness of arthroscopic ASB ACL reconstruction is better than that of arthroscopic OSB ACL reconstruction, especially in controll ing rotational stabil ity.
ObjectiveTo review the advances in utilizing paracrine effect of stem cells in knee osteoarthritis (OA) treatment.MethodsThe researches in applying stem cells derived conditioned medium, extracellular matrix, exosomes, and microvesicles in knee OA treatment and cartilage repair were reviewed and analyzed.ResultsThe satisfying outcomes of using different products of stem cells paracrine effect in knee OA condition as well as cartilage defect is revealed in studies in vitro and in vivo. The mechanism including suppressing the intraarticular inflammation, the apoptosis of chondrocytes, and the degradation of cartilage matrix, while enhancing the synthesis of cartilage matrix, the differentiation of in-situ stem cells into chondrocytes and the migration to the affected area. The effectiveness can be further improved supplemented with the tissue engineering methods or gene modification.ConclusionCompared with the traditional stem cell therapy, applying the products from paracrine effect of stem cells in knee OA treatment is more economical and safer, presenting great potential in clinical practice.
ObjectiveTo investigate the position of the anterior fracture line in AO/Orthopaedic Trauma Association (AO/OTA) type A2 unstable intertrochanteric fractures and its impact on the incidence of anterior cortical reduction loss after cephalomedullary nail fixation. MethodsA clinical data of 95 patients with intertrochanteric fractures who met the selection criteria between April 2020 and February 2023 was retrospectively analyzed. All patients were treated with cephalomedullary nail fixation, and the intra- and post-operative imaging data were complete. Among them, there were 37 males and 58 females. The age ranged from 61 to 97 years, with an average of 79.6 years. The time from injury to operation ranged from 7 hours to 11 days, with an average of 2.8 days. According to the 2018-AO/OTA classification standard, there were 39 cases of type 31-A2.2 and 56 cases of type 31-A2.3. Intraoperative fluoroscopy was used to record the number of patients with satisfactory fracture alignment. The preoperative CT data were imported into Mimics17.0 software to simulate the fracture reduction and measure the distance between the anterior fracture line and the intertrochanteric line bony ridge. The fractures were classified as transcapsular fractures, extra-capsular fractures, and intra-capsular fractures according to the distance. CT three-dimensional reconstruction was performed within 2 weeks after operation to observe the number of patients with anterior cortical reduction loss. The postoperative anterior cortical reduction loss incidence in patients with satisfactory fracture alignment, and the relationship between postoperative anterior cortical reduction loss and the position of the anterior fracture line were observed. Results There were 52 cases (54.7%) of transcapsular fractures, 24 cases (25.3%) of extra-capsular fractures, and 19 cases (20.0%) of intra-capsular fractures. Among them, 41 of the 52 transcapsular fractures had satisfactory fracture alignment, and 4 (9.8%) of them experienced anterior cortical reduction loss after operation; 19 of the 24 extra-capsular fractures had satisfactory fracture alignment, and no anterior cortical reduction loss occurred; 16 of the 19 intra-capsular fractures had satisfactory fracture alignment, and 7 (43.8%) of them experienced anterior cortical reduction loss after operation. There was a significant difference in the incidence of anterior cortical reduction loss between groups (χ2=8.538, P=0.003). All patients were followed up 3-26 months (mean, 9 months). Among them, 91 cases had fracture healing, and 4 cases had nonunion.Conclusion In AO/OTA type A2 unstable intertrochanteric fractures, where the anterior fracture line is located within the joint capsule, there is a high risk of anterior cortical reduction loss after operation.