The efficacy and safety of tranexamic acid in rheumatoid arthritis patients undergoing simultaneous bilateral total knee arthroplasty: a multicenter retrospective study.

BACKGROUND: The efficacy and safety of tranexamic acid (TXA) in reducing blood loss following total knee arthroplasty (TKA) in patients with osteoarthritis have been widely confirmed. However, there is still a paucity of the evidences regarding the effectiveness of TXA in patients with rheumatoid arthritis (RA). The purpose of the study is to explore the efficacy and safety of intravenous TXA on blood loss and transfusion risk following simultaneous bilateral TKA (SBTKA) in patients with RA. METHODS: As a multicenter retrospective study, a total of 74 patients diagnosed with RA who underwent SBTKA were assigned into TXA group (15 mg/kg intravenous TXA before skin incision, n = 50) and control group (no TXA use, n = 24). The primary outcomes were total blood loss (TBL) and intraoperative blood loss (IBL). The secondary outcomes were hemoglobin (Hb) and hematocrit (Hct) drop on postoperative day 3, transfusion rate and volume, ambulation time, length of stay, hospitalization expenses and the incidence of complications. RESULTS: The mean TBL, IBL and transfusion volume in TXA group were significantly lower than those in control group. The Hb and Hct drop on postoperative day 3 in control group were higher than those in TXA group (p<0.05). The similar trend was detected on transfusion rate, ambulation time and length of stay. The incidence of complications and hospitalization expenses did not differ significantly between the two groups (p>0.05). CONCLUSIONS: TXA could effectively reduce blood loss, decrease transfusion risk, shorten ambulation time and length of stay following SBTKA in patients with RA, without increasing the risk of complications.

Risk factors of opioid use associated with an enhanced-recovery programme after total knee arthroplasty.

BACKGROUND: Characterizing the impacts of postoperative opioid use on total knee arthroplasty (TKA) patients may help optimize the pain management after TKA. The aim of the study is to examine the prevalence and risk factors for opioid use with an enhanced-recovery programme after primary TKA. METHODS: We identified 361 patients undergoing TKA, and separated those on the basis of whether to receive opioid use after surgery. Themultivariate logistic regression model was used to identify independent risk factors for opioid use after primary TKA. Length of stay (LOS) and postoperative complications were also recorded and compared. RESULTS: The prevalence of opioid use after primary TKA was 23.0%. The significant risk factor was the longer operative time (OR [odds ratio] = 1.017, 95% CI [confidence interval] = 1.001 to 1.032, p = 0.034) and the protective factor was the utilization of tranexamic acid(OR= 0.355, 95% CI = 0.161 to 0.780, p = 0.010). In addition, the LOS was longer in opioid group (p < 0.05). CONCLUSION: Considering the adverse health effects of opioid use, strategies need to be developed to prevent persistent opioid use after TKA. Reducing operative time and the application of tranexamic acid could lower the risk of opioid use with an enhanced-recovery programme after primary TKA.

Local intra-articular injection of resveratrol delays cartilage degeneration in C57BL/6 mice by inducing autophagy via AMPK/mTOR pathway.

Autophagy is an essential cellular homeostasis mechanism that was found to be compromised in aging and osteoarthritis (OA) cartilage. Previous studies showed that resveratrol can effectively regulate autophagy in other cells. The purpose of this study was to determine whether the chondroprotective effect of resveratrol was related to chondrocyte autophagy and to elucidate underlying mechanisms. OA model was induced by destabilization of the medial meniscus (DMM) in 10-week-old male mice. OA mice were treated with resveratrol with/without 3-MA for 8 weeks beginning 4 weeks after surgery. The local intra-articular injection of resveratrol delayed articular cartilage degradation in DMM-induced OA by OARSI scoring systems and Safranin O-fast green. Resveratrol treatment increased Unc-51-like kinase1, Beclin1, microtubule-associated protein light chain 3, hypoxia inducible factor-1α, phosphorylated AMPK, collagen-2A1, Aggrecan expressions, but decreased hypoxia inducible factor-2α, phosphorylated mTOR, matrix metalloproteinases13 and a disintegrin and metalloproteinase with thrombospondin motifs 5 expressions. The effects of resveratrol were obviously blunted by 3-MA except HIF and AMPK. These findings indicate that resveratrol intra-articular injection delayed articular cartilage degeneration and promoted chondrocyte autophagy in an experimental model of surgical DMM-induced OA, in part via balancing HIF-1α and HIF-2α expressions and thereby regulating AMPK/mTOR signaling pathway.

[Posterior popliteal fossa S-shaped incision with double-window approach in treating posterior column of tibial plateau fractures].

OBJECTIVE: To evaluate the effectiveness and safty of posterior popliteal fossa S-shaped incision with double-window approach for the treatment of posterior column of tibial plateau fractures. METHODS: A retrospective analysis was made on the clinical data of 13 patients with complex tibial plateau fractures involving both posteromedial and posterolateral columns between May 2015 and July 2017. There were 9 males and 4 females, aged 33-64 years (mean, 46.5 years). The causes of injury included traffic accident in 5 cases, falling from height in 2 cases, falling from electric bicycle in 4 cases, and falling because of skiing in 2 cases. The preoperative range of motion of the affected knees was (35.1±9.2)°. The time from injury to surgery was 7-19 days (mean, 13.3 days). All patients underwent a posterior popliteal fossa S-shaped incision through the window of medial heads of gastrocnemius muscle (medial window) and the window between medial and lateral head of gastrocnemius muscle (popliteal fossa window) approaches. After a good visual control of fracture reduction, both posteromedial and posterolateral columns of tibial plateau fractures were fixed with buttress plate respectively. Bone union, limb alignment, articular surface, and range of motion were estimated after operation. The American Hospital for Special Surgery (HSS) score was used to evaluate functional outcomes of knees. RESULTS: After operation, 1 patient had fat liquefaction and dehiscence of incision, which healed after expanding the wound; the other patients' incisions healed by first intention, and no vascular or nerve injury occurred during operation. All the 13 patients were followed up 12-18 months (mean, 16 months). The X-ray films showed that all patients obtained good fracture unions, the fracture healing time was 14-22 weeks (mean, 18 weeks). At 12 months after operation, the articular surface was smooth without collapse, and the knee range of motion was (109.5±13.6)°, showing significant difference when compared with preoperative value ( t=18.879, P=0.000). No complication of infection, re-displacement of fracture, or secondary varus/valgus deformity was observed during follow-up. The HSS score was 82-96 (mean, 89.6) at 12 months after operation, with the result of excellent in 10 cases and good in 3 cases. CONCLUSION: The posterior column fracture of tibial plateau involving both posteromedial and posterolateral columns treated by double-window approach through posterior popliteal fossa S-shaped incision is safe and effective, with satisfactory results and good recovery of knee joint function.

Dextran-based hydrogel with enhanced mechanical performance via covalent and non-covalent cross-linking units carrying adipose-derived stem cells toward vascularized bone tissue engineering.

Hydrogels for biomedical applications were limited toward bone tissue engineering due to the poor mechanical performance. Tough hydrogels with strong and elastic features have received extensive attention, the application of which, however, was limited by their degradation. The present study introduced an approach to enhance mechanical properties of hydrogel while ensuring its degradation. Carboxyl dextran (Dex) was grafting modified by poly (ε-caprolactone) (PCL), sequentially followed by being cross-linked through polyethyleneglycol 400 (PEG400) to yield a gel with covalent cross-linking units in DMSO. The gel was underwent solvent displacement in H2 O to induce hydrophobic association of PCL to form non-covalent cross-linking units. The tough Dex-g-PCL hydrogel showed maximum strain of Dex-g-PCL hydrogel was 90% ± 6%, with the corresponding stress of 2.7 ± 0.2 MPa, which was significantly enhanced when comparing to dextran hydrogel (maximum strain 65% ± 5%, with the corresponding stress of 0.225 ± 0.06 MPa). Most hydrogel degraded after 12 w in vivo with only a little residues. Adipose-derived stem cells (ASCs) proliferated well after being seeded in hydrogel to form micro-mass at 14 days post-seeding. In vitro and in vivo angiogenesis, as well as in vitro osteogenesis illustrated the potential of the Dex-g-PCL hydrogel carrying ASCs toward vascularized bone tissue engineering. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1120-1131, 2019.

[Suture-bridge fixation under arthroscopy in treatment of tibial eminence avulsion fracture of anterior cruciate ligament in adolescents].

Objective: To explore effectiveness of suture-bridge fixation under arthroscopy in treatment of tibial eminence avulsion fracture of anterior cruciate ligament in adolescents. Methods: Between June 2013 and October 2016, 18 adolescent patients suffered tibial eminence avulsion fracture of anterior cruciate ligament were treated by suture-bridge fixation under arthroscopy. There were 11 males and 7 females with an average age of 12.5 years (range, 5-17 years). The injury caused by bruise in 6 cases, by sprain in 4 cases, and by sport injury in 8 cases. The interval between injury and admission ranged from 2 hours to 10 months (mean, 2 months). The results of preoperative Lachman and anterior drawer tests were positive. There were 10 cases of knee pain, 4 cases of knee extension limitation, and 4 cases of knee extension without strength. According to the Meyer-McKeever classification criteria, 12 cases were type Ⅱ and 6 cases were type Ⅲ. Results: All incisions healed by first intention. All 18 patients were followed up 10-18 months after operation, with an average of 12 months. Postoperative X-ray films showed that all fractures healed after 6-12 weeks (mean, 8 weeks). The results of postoperative Lachman and anterior drawer tests were negative. At last follow-up, the Lysholm knee score was 90.1±5.0 and 93.1±6.2 for affected and unaffected sides, respectively, showing no significant difference between affected and unaffected sides( t=0.669, P=3.184ï¼»?ï¼½). There was no premature closure of skeleton or leg length discrepancy and deformity. Conclusion: For tibial eminence avulsion fracture of anterior cruciate ligament in adolescents, the suture-bridge fixation under arthroscopy is an effective method with many advantages, such as minimal invasion, reliable fixation, good fracture healing, and no need for second operation to remove implants.

[A modified Laprade technique in treatment of lateral multi-ligament injuries of knee].

Objective: To evaluate the short-term effectiveness of a modified Laprade technique in the treatment of lateral multi-ligament injuries of knee by anatomical reconstruction of posterolateral complex (PLC) and anterior lateral ligament (ALL). Methods: Between June 2013 and July 2015, 13 cases of lateral multi-ligament injuries of knee were treated. There were 9 males and 4 females with an average age of 38 years (range, 23-49 years). The injury was caused by traffic accident in 7 cases, falling from height in 4 cases, and sport injury in 2 cases. The time between injury and operation was 18-92 days (mean, 43 days). The results of anterior and posterior drawer tests and Lachmann test were positive, and all cases complicated by varus and external rotation instability. The Lysholm score of the knee was 38.4±7.7. According to International Knee Documentation Committee (IKDC) scoring, all were rated as grade D. According to Fanelli classification criteria, all were classified as type C. Anterior cruciate ligament, posterior cruciate ligament, PLC, and ALL were reconstructed simultaneously with autogenous tendon. Results: All incisions healed at stage I and no complication occurred. All patients were followed up 12-36 months (mean, 19 months). At last follow-up, the results of anterior and posterior drawer tests and Lachmann test were negative; 2 cases had varus instability, and 1 cases had external rotation instability. There was no anterior external rotation instability. The Lysholm score of the knee was 88.6 ±12.7, showing significant difference when compared with preoperative score ( t=13.852, P=0.000). According to IKDC scoring, 8 cases were rated as grade A, 4 as grade B, and 1 as grade C; significant difference was found when compared with preoperative value ( Z=3.182, P=0.000). Conclusion: In the treatment of lateral multi-ligament injuries knee, anatomical reconstruction of PLC and ALL with a modified Laprade technique can obtain good short-term effectiveness.

Intra-articular resveratrol injection prevents osteoarthritis progression in a mouse model by activating SIRT1 and thereby silencing HIF-2α.

We investigated the feasibility of the intra-articular injection of resveratrol for preventing the progression of existing cartilage degeneration in a mouse model of osteoarthritis (OA). The effects of resveratrol on the expression of silent information regulator 2 type 1 (SIRT1), hypoxia-inducible factor-2α (HIF-2α) and catabolic factors in OA cartilage was explored. OA was induced in the mouse knee via destabilization of the medial meniscus (DMM). Resveratrol was injected weekly into the operated knee beginning 4 weeks after surgery. The OA phenotype was evaluated via histological and immunohistochemical analyses at 8 weeks after DMM. Western blot analysis was performed to identify whether resveratrol modulated the interleukin (IL)-1ß-induced expression of HIF-2α in human chondrocytes. Histologically, resveratrol treatment preserved the structural homeostasis of the articular cartilage and the subchondral bone. Following resveratrol injection, the expression of collagen type II was retained, but the expression of inducible nitric oxide synthase and matrix metalloproteinase-13 was reduced in OA cartilage. Moreover, the administration of resveratrol significantly induced the activation of SIRT1 and the inhibition of HIF-2α expression in mouse OA cartilage and in IL-1ß-treated human chondrocytes. These findings indicate that the intra-articular injection of resveratrol significantly prevents the destruction of OA cartilage by activating SIRT1 and thereby suppressing the expression of HIF-2α and catabolic factors.

Expression and purification of recombinant nattokinase in Spodoptera frugiperda cells.

A recombinant baculovirus, rv-egfp-NK, containing a reporter gene encoding the enhanced green fluorescent protein (EGFP), was used to express nattokinase (NK), a fibrinolytic enzyme, in Spodoptera frugiperda (SF-9) cells. The recombinant protein also included a histidine tag for purification using Ni(2+) resins. The recombinant NK, approximately 30 kDa, retained fibrinolytic activity (60 U/ml). The integration of the EGFP expression cassette in the Bac-to-Bac system is thus an effective method for the expression and purification of recombinant NK protein in Spodoptera frugiperda insect cells.