Biomimetic Biphasic Electrospun Scaffold for Anterior Cruciate Ligament Tissue Engineering

Background@#Replacing damaged anterior cruciate ligaments (ACLs) with tissue-engineered artificial ligaments is challenging because ligament scaffolds must have a multiregional structure that can guide stem cell differentiation. Here, we designed a biphasic scaffold and evaluated its effect on human marrow mesenchymal stem cells (MSCs) under dynamic culture conditions as well as rat ACL reconstruction model in vivo. @*Methods@#We designed a novel dual-phase electrospinning strategy wherein the scaffolds comprised randomly arranged phases at the two ends and an aligned phase in the middle. The morphological, mechanical properties and scaffold degradation were investigated. MSCs proliferation, adhesion, morphology and fibroblast markers were evaluated under dynamic culturing. This scaffold were tested if they could induce ligament formation using a rodent model in vivo. @*Results@#Compared with other materials, poly(D,L-lactide-co-glycolide)/poly(ε-caprolactone) (PLGA/PCL) with mass ratio of 1:5 showed appropriate mechanical properties and biodegradability that matched ACLs. After 28 days of dynamic culturing, MSCs were fusiform oriented in the aligned phase and randomly arranged in a paving-stone-like morphology in the random phase. The increased expression of fibroblastic markers demonstrated that only the alignment of nanofibers worked with mechanical stimulation to promote effective fibroblast differentiation. This scaffold was a dense collagenous structure, and there was minimal difference in collagen direction in the orientation phase. @*Conclusion@#Dual-phase electrospun scaffolds had mechanical properties and degradability similar to those of ACLs. They promoted differences in the morphology of MSCs and induced fibroblast differentiation under dynamic culture conditions. Animal experiments showed that ligamentous tissue regenerated well and supported joint stability.

Biomimetic Biphasic Electrospun Scaffold for Anterior Cruciate Ligament Tissue Engineering

Background@#Replacing damaged anterior cruciate ligaments (ACLs) with tissue-engineered artificial ligaments is challenging because ligament scaffolds must have a multiregional structure that can guide stem cell differentiation. Here, we designed a biphasic scaffold and evaluated its effect on human marrow mesenchymal stem cells (MSCs) under dynamic culture conditions as well as rat ACL reconstruction model in vivo. @*Methods@#We designed a novel dual-phase electrospinning strategy wherein the scaffolds comprised randomly arranged phases at the two ends and an aligned phase in the middle. The morphological, mechanical properties and scaffold degradation were investigated. MSCs proliferation, adhesion, morphology and fibroblast markers were evaluated under dynamic culturing. This scaffold were tested if they could induce ligament formation using a rodent model in vivo. @*Results@#Compared with other materials, poly(D,L-lactide-co-glycolide)/poly(ε-caprolactone) (PLGA/PCL) with mass ratio of 1:5 showed appropriate mechanical properties and biodegradability that matched ACLs. After 28 days of dynamic culturing, MSCs were fusiform oriented in the aligned phase and randomly arranged in a paving-stone-like morphology in the random phase. The increased expression of fibroblastic markers demonstrated that only the alignment of nanofibers worked with mechanical stimulation to promote effective fibroblast differentiation. This scaffold was a dense collagenous structure, and there was minimal difference in collagen direction in the orientation phase. @*Conclusion@#Dual-phase electrospun scaffolds had mechanical properties and degradability similar to those of ACLs. They promoted differences in the morphology of MSCs and induced fibroblast differentiation under dynamic culture conditions. Animal experiments showed that ligamentous tissue regenerated well and supported joint stability.

Meta analysis of efficacy and safety of non-steroidal anti-inflammatory drugs in preventing heterotopic ossification after hip arthroscopy / 中华创伤杂志

Objective To evaluate the efficacy and safety of non-steroidal anti-inflammatory drugs (NSAIDs) in preventing heterotopic ossification after hip arthroscopy.Methods Literature search was conducted in PubMed,Embase,Cochrane Library,CNKI and Wanfang data with time range from January 1973 to November 2017.Clinical case control articles on NSAIDs in preventing heterotopic ossification after hip arthroscopy were screened based on the inclusion and exclusion criteria.Meta analysis was done using RevMan 5.3 software to investigate the incidence of complications such as heterotopic ossification and gastrointestinal bleeding after hip arthroscopy in patients taking NSAIDs orally.Results Six articles were included in the study,with a total of 754 cases and 536 controls.NSAIDs reduced the incidence of heterotopic ossification after hip arthroscopy (RR =0.09,95％ CI 0.03-0.27,P ＜ 0.05).Selective COX-2 inhibitor celecoxib (RR =0.17,95％ CI 0.03-0.91,P ＜ 0.05) and PG synthase inhibitor of naproxen (RR =0.17,95％ CI 0.09-0.32,P ＜ 0.05) were also effective in preventing heterotopic ossification.There was no significant difference in the incidence of gastrointestinal complications between the cases and controls after NSAIDs prophylaxis (RR =2.17,95％ CI 0.92-5.12,P ＞ 0.05).Conclusion NSAIDs can effectively reduce the incidence of heterotopic ossification after hip arthroscopy and does not increase the incidence of postoperative gastrointestinal complications.Therefore,it is effective and safe to use NSAIDs to prevent the occurrence of heterotopic ossification after hip arthroscopy.

Research progress in complications of hip arthroscopy / 中华创伤杂志

Hip arthroscopy has become a routine treatment for the localized hip lesions.With the rapid development of arthroscopy,the number of surgeries has increased greatly.Though hip arthroscopy is considered as low risk operation,its complications have been constantly reported and noted.There are two major types in hip arthroscopy surgeries:conventional operative complications and special complications.Conventional operative complications include venous thromboembolism,hemorrhage,and pain.Special complications are associated with arthroscopic techniques and local anatomical structures of the hip,such as the perineal nerve,the lateral femoral cutaneous nerve,the acetabular labium or the iatrogenic injury of the cartilage surface of the femoral head.Hip arthroscopy has obvious advantages such as small surgical wound and rapid recovery,but its complications can not be ignored.Joint surgeons must fully recognize it and keep vigilant so as to avoid complications as much as possible.This review will systematically elaborate the complications of hip arthroscopic surgery from general and special aspects so as to provide ideas for reducing the occurrence of complications in hip arthroscopic surgery.

Research progress in risk factors for venous thrombosis after knee arthroscopy / 中华创伤杂志

Venous thromboembolism (VTE) is a common complication of hip and knee arthroplasty and of many major orthopedic surgeries.VTE mainly includes two aspects,ie,deep vein thrombosis (DVT) and pulmonary embolism (PE).Symptomatic PE is likely to endanger patients' life,resulting in irreversible severe consequences.With the return of venous blood,DVT may also fall off at any time,forming a new PE.Therefore,the prevention of VTE in large orthopedic surgeries has been highly valued by scholars worldwide.However,the problem of VTE after arthroscopic surgery has not drawn much attention from clinicians.Researchers have not reached a consensus on whether routine anticoagulation therapy is required after surgery because of VTE's low incidence and discrepancy among various studies (0.42％-17.9％).With a large number of knee arthroscopy being performed per year,the postoperative VTE incidence can not be ignored.For these reasons,some scholars have suggested that patients after knee arthroscopy should be stratified and that patients with a higher risk of postoperative VTE need to be given anticoagulant therapy.Risk factors for VTE after knee arthroscopy may have effects on the clinical treatment of patients.Therefore,a review of the literature to explore the possible risk factors for postoperative VTE was conducted.

Application of beach chair position and lateral decubitus position in shoulder arthroscopy / 中华骨科杂志

The clinical application of arthroscopic minimally invasive treatment of shoulder joint disease technology has become a routine,and it has been widely carried out around the world.Compared with the traditional open surgery,it only needs to establish a few channels in the shoulder and then the diagnosis and treatment of the structure under the acromion and glenoid joint internal lesions can be completed through the arthroscopic technique under direct vision,of course,including local collection of pathological specimens.Shoulder arthroscopic surgery has the advantages of simple operation technique,small economic burden of patients,small tissue trauma,quick recovery and high accuracy of disease diagnosis.At present,there are two main options for shoulder arthroscopy:the beach chair position (BCP) and the lateral decubitus position (LDP).The choice of surgical position for surgeons is closely related to the intraoperative operation,the risk of complications,the efficacy of surgery,and the cost of setting the posture.Shoulder arthroscopy of these two positions have their own advantages and disadvantages:in the BCP,the surgeon gets a better anatomical operation experience,if necessary,can be converted into open surgery at any time.Without continuous traction,upper limb nerve and vascular damage caused by traction can be avoid.But the incidence of cerebral ischemic events in patients may increase in the BCP.There is also possibility of the nerve damage of the pillow small nerve,great auricular nerve,lateral femoral cutaneous nerve and other nerves.In theory the risk of air embolism in the patients will increase in the BCP,and the cost of setting the position is also higher than the LDP.While in the LDP due to the patient's forearm continuous traction,the surgeon can get a more extensive operating space,and the occurrence of cerebral ischemic events is very rare.In the treatment of anterior shoulder instability after shoulder arthroscopic surgery,there is a lower recurrence rate in the LDP.The cost of setting the position is also significantly lower than the BCP.Of course,the disadvantages of the LDP is also obvious.In the LDP,the brachial plexus and other nerves or vascular injury may increase due to the continuous traction of the forearm.Meanwhile sustained traction in the LDP is also a risk factor for thrombosis,and so on.Therefore,there is still a debate about the optimal location of the shoulder arthroscopy.Many clinicians choose shoulder arthroscopic position based on their own experience and habits.

Bone cement spacers and Link spacers for treatment of infection due to total hip arthroplasty:a comparative study / 中华创伤杂志

Objective To compare the efficacy of self-made bone cement spacers containing vancomycin(vancomycin spacer)and Link infection-treating spacers(Link type spacer)for chronic infection after total hip arthroplasty(HTA)and investigate the choice of spacers for the two-stage revision of infection.Methods The study included 26 patients with infection combined with HTA,aged 32-82 years(mean 69.5 years).In the first stage,after complete debridement and removal of infected prostheses,the vancomycin spacers were implanted in 14 patients,while the Link type spacers were implanted in the rest 12 patients.Two weeks of intravenous administration of antibiotics and then six weeks of oral administration of antibiotics were done postoperatively.White blood cells(WBCs),erythrocyte sedimentation rate(ESR)and C-reactive protein(CRP)were measured periodically after operation.THA revision was performed in the second stage.Clinical outcomes were evaluated according to the pre-and post-operative Harris hip score.Results All patients obtained primary healing of incision after complete debridement,removal of prostheses and implant of the vancomycin spacers or the Link type spacers.Two-stage revision surgery was performed at 3-11.5 months after the one-stage surgery(mean 5.2 months).The follow-up ranging from 12 to 33 months(mean 20.8 months)manifested no signs of reinfection.The mean Harris hip score was increased from 27.9 points before one-stage operation to 52.9 points before two-stage operation,and 83.6 points at the latest follow-up(P＜0.05)One of 12 vancomycin spacers was broken before the revision surgery,as was free from the Link spacers.Conclusions(Ⅰ)Two-stage revision is an effective method in the treatment of infection after HTA because of high eradication rate of infection,effective pain relief and good postoperative functional result.(2)The vancomycin spacers and the Link type spacers can both effectively control infection and restore part of limb function.(3)The Link type spacers take advantages of simple in operation and the function improvement of the limbs during the intermittent period of treatment,but disadvantages of the catheters being prone to block,limited slow release of antibiotics and high cost of treatment.Thereby,the Link type spacer is suitable for the patients with relatively strong constitution,little serious infection,or high requirement of limb functions at the interval of two operations.