Advances in the role of the infrapatellar fat pad in the initiation and progression of knee osteoarthritis / 中华骨科杂志

Osteoarthritis (OA) is a common chronic debilitating disease among middle-aged and old people,which can occur in the hip,knee,ankle,spine and other joints,but it is most commonly seen in the knee.The clinical manifestations of the knee osteoarthritis (KOA) include pain,swelling,stiffness,joint deformity,seriously affectting the quality of life.Mechanical and metabolic factors have been shown to play roles in the initiation and progression of this disease,resulting in a slow,progressive pathological process,and the normal balance of anabolic and catabolic activities of the chondrocytes has been disrupted.The mechanical factors are the joint imbalance caused by cartilage degeneration and ligament damage,and biochemical factors are mainly the changes of the joint microenvironment caused by the dysregulation of chondrocytes and synovitis.Infrapatellar fat pad (IPFP)is situated in the lower part of patella and femoral condyle,between tibia condyle and the patellar ligament,and it is an intracapsular but extrasynovial elastic fiber adipose tissue.Researches have shown that besides the synovial membrane,ligament,cartilage and bone,IPFP may play an important role in the onset and progression of KOA and knee pain.IPFP has long been regarded as a structural fatty tissue without metabolic reactions,thus often been neglected,what's more,to get a clear vision in knee surgery,IPFP is often partially or totally resected,but recently owning to its potential biological mechanics,endocrine function,which can produce a variety of inflammatory cytokines,chemokines,rich in nerve fiber structure and IPFP-adipose derived stem cells,more and more scholars pay attention to the IPFP.IPFP may play a protective role in the early stage of KOA by cushioning shock,stabilizing lubrication,but this article emphatically explain how IPFP play a desctructive role in the initiation and progressionof KOA through leptin,adiponectin,and many other adipocytokines,or inflammatory mediators,so as to get further understanding of KOA,and discuss whether IPFP should be resected or not in knee surgery,providing a new method to the prevention and treatment of KOA.

Human beta defense 3/poly(lactic-co-glycolic acid) controlled-release microspheres preparation and in vitro release profile / 中国组织工程研究

BACKGROUND: A simple use of antibiotic drugs as anti-infection therapy after joint replacement is not enough for subsequent debridement and secondary revision surgeries. Therefore, our team intended to confirm the feasible use of controlled-release microspheres in the local anti-infection treatment.OBJECTIVE: To prepare the Human beta defense 3 (HBD-3)/poly(lactic-co-glycolic acid) (PLGA) micro-spheres and to investigate the microsphere physicochemical properties and drug release profile in vitro.METHODS: With PLGA as a carrier,HBD-3/PLGA controlled-release microspheres were prepared by using double emulsion-solvent evaporation method. Scanning electron microscopy was used to observe its surface morphology.The size of each microsphere was accurately determined using scaleplate. Drug loading capacity and encapsulation efficiency of HBD-3/PLGA controlled-release microspheres were calculated using spectrophotometer. HBD-3/PLGA microsphere controlled-release time was determined in order to analyze the drug release profile of the microsphere. RESULTS AND CONCLUSION: The HBD-3/PLGA controlled-release microsphere possessed smooth surface, uniform distribution and good liquidity.The average particle size was 219.49 nm, the drug loading capacity of HBD-3 was (20.67±0.17)% and the encapsulation efficiency was (54.52±1.31)%. The cumulative release percentage of HBD-3 was(74.12±0.43)%. The HBD-3/PLGA controlled-release microsphere has well controlled-release performance in vitro. In theory, the purpose of antibacterial controlled-release can be achieved,laying a foundation for subsequent animal antibacterial experiments.

Two-Stage Primary Total Knee Arthroplasty with Well-Designed Antibiotic-Laden Cement Spacer Block for Infected Osteoarthritic Knees: The First Case Series from China.

OBJECTIVE: We aimed to assess the efficacy of applying a two-stage primary total knee arthroplasty (TKA) with an antibiotic-laden cement spacer block to treat infected osteoarthritic knees. METHODS: This retrospective study included 17 cases of severely infected osteoarthritic knees treated with two-stage primary TKA. Open debridement and irrigation with insertion of a well-designed antibiotic cement spacer was performed as the first stage. Systemic antibiotics were used in the interval period. Two-stage TKAs were performed after elimination of infection. The pre- and post-operative Hospital for Special Surgery Knee (HSS) score as well as range of motion (ROM) were assessed. RESULTS: Elimination of infection was achieved in 16 patients. C-reactive protein returned to normal levels in an average of 3.4 wks (range, 1-7 wks), whereas erythrocyte sedimentation rate (ESR) recovered in an average of 11.4 wks (range, 6-19 wks). The average interval between the two-stage operations was 16.8 wks (range, 10-27 wks). Compared with the pre-operative level, the mean HSS score had a substantial increase after the first-stage and second-stage surgery (p<0.05). The post-operative maximum extension degree was smaller and the maximum flexion and ROM degree were larger than the pre-operative degree (all p<0.05). There were no recurrent infections and no patients lost to follow-up. One patient chose to receive arthrodesis because of uncontrolled infection after numerous operations and treatments. CONCLUSIONS: Two-stage TKA with open debridement, irrigation, and insertion of a well-designed antibiotic-laden cement spacer at the first stage could provide effective pain relief and function restoration as well as infection control in the interval. This treatment protocol provided an encouraging final clinical outcome, which could be a reliable alternative for patients with infected osteoarthritic knees.

Changes of hemoglobin and hematocrit in elderly patients receiving lower joint arthroplasty without allogeneic blood transfusion / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>It has rarely been reported about the changes of hemoglobin (Hb) and hematocrit (Hct) in elderly patients receiving total knee arthroplasty (TKA) or total hip arthroplasty (THA). This study aimed to evaluate the changes of Hb and Hct after TKA or THA in elderly patients, and analyze its relationship with sex and type of arthroplasty.</p><p><b>METHODS</b>This is a prospective cohort study, including 107 patients receiving TKA or THA without allogeneic blood transfusion. There were 54 males and 53 females, with a mean age of 69.42 years. Levels of Hb and Hct were examined preoperatively and during the 6 months follow-up after operation.</p><p><b>RESULTS</b>Levels of Hb and Hct decreased postoperatively and reached their minimum points on postoperative day 4. Thereafter, Hb and Hct recovered to their preoperative levels within 6-12 weeks. No significant differences in the levels of Hb and Hct were noticed between different sexes. THA patients showed significantly greater drop in Hb and Hct than TKA patients in the first 4 days postoperatively (P < 0.05).</p><p><b>CONCLUSIONS</b>Levels of Hb and Hct decreased during the first 4 days after arthroplasty and gradually returned to their normal levels within 6-12 weeks postoperatively. THA may be associated with higher postoperative blood loss than TKA.</p>

Early postoperative pain between the first and second staged bilateral total knee arthroplasty:a retrospective comparative analysis / 中国组织工程研究

BACKGROUND:Total knee arthroplasty solves a great pain for patients with severe knee joint disease, and its clinical curative effects have been general y accepted. In the clinic, the formulation of clinical analgesic program of the two surgeries in patients undergoing double knee prosthesis lacks of the support of evidence-based medicine. OBJECTIVE:To compare the differences in pain during early stage of primary and secondary surgeries in bilateral total knee arthroplasty, and to provide evidence for clinical analgesic programs. METHODS:A total of 87 patients receiving staged bilateral total knee arthroplasty from January 2009 to January 2013 were retrospectively analyzed. Visual analogue scale was compared at 24, 48 and 72 hours after first and second staged total knee arthroplasty, including seating and maximum flexion position. In addition, the difference in early pain score was compared between second and first total knee arthroplasty in different intervals (less than 6 months, 6-12 months, more than 12 months). RESULTS AND CONCLUSION:The visual analogue scale scores at seating and maximum flexion position at 24 and 48 hours after second total knee arthroplasty were significantly higher than the first surgery. No significant difference in visual analogue scale scores was detected between 72-hour seating and maximum flexion position. Visual analogue scale scores were significantly higher in the interval of less than 6 months than in the 6-12 month group and more than 12 month group in the 24-hour seating and maximum flexion position after second total knee arthroplasty. No significant difference in visual analogue scale scores was detected between the 6-12 month group and more than 12 month group at seating and maximum flexion position. Results suggested that the pain of second surgery was obviously higher than the first surgery within 48 hours after staged bilateral total knee arthroplasty, and this can provide a clinical evidence to enhance the analgesic strategy in the second staged bilateral total knee arthroplasty. The interval between two surgeries also affected the early pain after second surgery. Considered the aspect of postoperative pain, it is better to suggest the interval between first and second surgeries in staged total knee arthroplasty should be more than 6 months. This can reduce pain after second surgery, elevate patient’s satisfaction and accelerate the speed of recovery.