Objective:To evaluate the clinical outcomes of total knee arthroplasty (TKA) assisted by 3D printing in the treatment of traumatic osteoarthritis secondary to severe knee deformity after old tibial plateau fracture.Methods:A retrospective study was conducted to analyze the clinical data of the 18 patients who had been treated for traumatic osteoarthritis secondary to severe knee deformity after old tibial plateau fracture at Department of Orthopaedics, The People's Hospital of Guizhou Province from March 2015 to June 2017. The cohort included 7 males and 11 females, with a mean age of (64.0±7.7) years. The left knee was affected in 12 cases and the right in 6 ones. The injury was caused by a traffic accident in 12 cases, by a fall from heights in 4 cases, and by a heavy object in 2 cases. The time from fracture to TKA was (5.9±2.8) years. All patients underwent TKA assisted by 3D printing after admission. Knee range of motion (ROM), Hospital for Special Surgery (HSS) knee score, and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were compared between preoperation and postoperative 6 months. Complications during the follow-up period were also recorded.Results:All the 18 patients completed a 6-month follow-up. At 6 months after operation, the knee ROM increased significantly from preoperative 85.1°±2.9° to 125.3°±1.3°, the HSS knee score increased significantly from preoperative (39.6±1.4) points to (75.8±1.8) points, and the WOMAC score decreased significantly from preoperative (49.3±1.0) points to (8.3±0.7) points in the 18 patients ( P<0.05). One patient experienced poor wound healing 1 week after operation, and 3 patients developed low-lying patella postoperatively. No such complications as prosthesis loosening, infection, or joint stiffness were reported during the follow-up period. Conclusion:For patients with traumatic osteoarthritis secondary to severe deformity following old tibial plateau fracture, TKA assisted by 3D printing can significantly improve their knee ROM and restore their limb function, but lead to no serious complications.

Objective:To evaluate the clinical outcomes of total knee arthroplasty (TKA) assisted by 3D printing in the treatment of traumatic osteoarthritis secondary to severe knee deformity after old tibial plateau fracture.Methods:A retrospective study was conducted to analyze the clinical data of the 18 patients who had been treated for traumatic osteoarthritis secondary to severe knee deformity after old tibial plateau fracture at Department of Orthopaedics, The People's Hospital of Guizhou Province from March 2015 to June 2017. The cohort included 7 males and 11 females, with a mean age of (64.0±7.7) years. The left knee was affected in 12 cases and the right in 6 ones. The injury was caused by a traffic accident in 12 cases, by a fall from heights in 4 cases, and by a heavy object in 2 cases. The time from fracture to TKA was (5.9±2.8) years. All patients underwent TKA assisted by 3D printing after admission. Knee range of motion (ROM), Hospital for Special Surgery (HSS) knee score, and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were compared between preoperation and postoperative 6 months. Complications during the follow-up period were also recorded.Results:All the 18 patients completed a 6-month follow-up. At 6 months after operation, the knee ROM increased significantly from preoperative 85.1°±2.9° to 125.3°±1.3°, the HSS knee score increased significantly from preoperative (39.6±1.4) points to (75.8±1.8) points, and the WOMAC score decreased significantly from preoperative (49.3±1.0) points to (8.3±0.7) points in the 18 patients ( P<0.05). One patient experienced poor wound healing 1 week after operation, and 3 patients developed low-lying patella postoperatively. No such complications as prosthesis loosening, infection, or joint stiffness were reported during the follow-up period. Conclusion:For patients with traumatic osteoarthritis secondary to severe deformity following old tibial plateau fracture, TKA assisted by 3D printing can significantly improve their knee ROM and restore their limb function, but lead to no serious complications.

Osteoarthritis is one of the most common chronic diseases in orthopedics.With increasing populations of aging and obese people,its incidence has risen year by year and become a major public health problem.The hallmark of osteoarthritis is cartilage destruction,the main cause of which is degradation of extracellular matrix by catabolic enzymes and death of chondrocytes caused by apoptosis or autophagy.Articular cartilage is a hypoxic environment because it lacks blood supply and the joint cavity is relatively closed.A hypoxic environment induces chondrocytes to produce a series of hypoxia-related molecules which can regulate the expression of catabolic enzymes,autophagy and apoptosis of chondrocytes for osteoarthritis.This paper aims to review recent reports on the relationship between hypoxic-related molecules and pathogenesis of osteoarthritis and discuss the role of hypoxia-related molecules in the pathogenesis of osteoarthritis.

Objective To explore a practical and feasible method for isolation,culture and identification of mouse bone marrow endothelial progenitor cells(EPCs).Methods Bone marrow-derived mononuclear cells isolated by density gradient centrifugation were cultured in endothelial cell growth medium-2 MV medium.Growth and morphological changes of the cells were observed under inverted microscopy.Cell proliferation was observed by cell counting kit-8 assay.Surface markers of the EPCs were detected by flow cytometry.Angiogenic tube formation was determined by Matrigel tube formation assay.Fluores cein isothiocyanat e-ulex europaeus agglutinin-1 (FITC-UEA-1) binding and Dil-Ac-LDL uptake capabilities were observed by fluorescent microscopy.Results In the early stage,the cells were round and spindle-shaped after induced culture for 4 days.After 7 days,the cells grew in colony arrangement and gradually increased in number.After 14 days,the cells were differently shaped,such as short shuttle and triangle.After 21 days,the typical "paving stone" appearance of the cells was observed.The cells were positive for endothelial markers in flow cytometry:CD34 + (84.3％),vascular endothelial growth factor receptor 2 + (74.1％),but CD45 + (4.04％).The cells were capable of forming capillary-like tubes,up-taking Dil-Ac-LDL and binding FITC-UEA-1 in Matrigels.Conclusions A reliable method for isolation,culture and identification of mouse bone marrow EPCs may be improved on the basis of previous experiences.Since the EPCs obtained by this method may be capable of good proliferation,large in number,and stable in biological characteristics,they can serve as ideal seed cells for related subsequent studies.

Objective To compare percutaneous suturing with sponge forceps and open suturing for repair of acute closed Achilles ruptures.Methods From March 2011 to June 2014,40 patients with acute closed Achilles rupture were enrolled in this study and randomized into 2 equal groups (n =20) which were subjected to percutaneous suturing with sponge forceps or open suturing.The operative time,incisive length,blood loss,wound healing,hospitalization time and complications were compared between the 2 groups.Their ankle functions were evaluated at postoperative 3,6,and 12 months according to American Orthopedic Foot and Ankle Society (AOFAS) ankle-hindfoot scores.Results The operative time (median,60.0 min),hospitalization time (median,8.5 d) and incisive length (median,8.0 cm) in the open suturing group were significantly greater than those in the sponge forceps group (32.5 min,7.0 d and 1.5 cm) (P ＜ 0.05).The blood loss (15.1 ± 13.7 mL) in the sponge forceps group was significantly less than in the open suturing group (54.2 ± 33.9 mL) (P ＜ 0.05).The open suturing group received an average follow-up of 16.8 months (from 12 to 23 months),witnessed superficial skin infection in 3 cases,and obtained AOFAS scores of 91.2 ± 5.1,95.2 ± 2.8 and 97.8 ± 1.6 at 3,6,and 12 months postoperatively.The sponge forceps group received an average follow-up of 15.6 months (from 12 to 24 months),witnessed wound healing in all cases,and obtained AOFAS scores of 90.6 ±5.3,94.I ±2.6 and 97.0 ±2.6 at 3,6,and 12 months postoperatively.The sponge forceps group obtained insignificantly lower AOFAS scores than the open suturing group (P ＞ 0.05).No injury to the sural nerve or tendon rerupture happened in either group.Conclusions In treatment of acute closed Achilles ruptures,compared with open suturing,percutaneous suturing with sponge forceps may be relatively easier without using special equipment,and additionally,may lead to lower incidence of incision complications and better short-term efficacy.

Objective To observe the effect of vancomycin-loaded calcium sulfate for one-stage treatment of chronic osteomyelitis.Methods A retrospective case series study was made on 26 patients with chronic osteomyelitis treated from January 2014 to April 2016.There were 23 males and 3 females,with a mean age of 35.8 years (range,16-90 years).After focus debridement of osteomyelitis,the cavities were filled with vancomycin-loaded calcium sulfate and systemic antibiotics were used.Meanwhile,gentamicin was added to patients showing unclear pathogens.Three patients underwent flap transfer surgery simultaneously due to the inadequate soft tissue coverage.Wound healing,local redness and swelling,sinus recurrence,recovery of osteomyelitis and repair of bone defect were detected after operation.Results All patients were followed up for 6-30 months (mean,19.5 months).Primary healing was achieved in all patients.One patient experienced wound exudate and was effectively managed by dressing change,one patient experienced inadequate local soft tissue coverage and was effectively managed by a second flap transfer surgery,and one patient remained wound unhealing after two surgeries and was cured by infected bone resection using the Masquelet induced membrane technique.Follow-up showed local bone defect was repaired in all patients without bone infection recurrence.Conclusions For patients with chronic osteomyelitis,one-stage surgery with vancomycin-loaded calcium sulfate can control infection with simultaneous repair of bone defect.Therefore,the procedure is a simple and effective method and worthy of clinical practice.