ABSTRACT
PURPOSE: Methylphenidate (MPH) derivative drugs are used because of psychostimulants effects on attention-deficit hyperactivity disorder in children and adults. As far as we know, toxic or anti-proliferative effects of MPH against cartilage tissue were not studied in the literature. The present study was carried out to investigate the possible effects of MPH on the proliferation, viability and differentiation of primary human chondrocytes, in vitro. METHODS: Monolayer primary chondrocyte cultures were prepared using osteochondral tissue obtained from patients who underwent a total knee prosthesis operation. Stock solution of MPH was prepared and aliquots having 1-1000 µM concentrations of the drug was composed. These solutions were applied to the wells containing cultured chondrocyte samples within the well plates. Control groups were composed of pure chondrocyte culture and no solution was added into them. All groups were evaluated at 24, 48 and 72 h in order to determine the possible negative effects of the drug on the chondrocytes. The data were evaluated by Tukey's honestly significantly different test following analysis of variance. RESULTS: In the group where MPH was applied, it was found that viability, proliferation and stage-specific embryonic antigen-1 protein expression were decreased in comparison to the control group. CONCLUSIONS: It was emphasized that clinicians should not disregard the fact that this drug might suppress chondrocyte cell proliferation and chondrogenic differentiation.
Subject(s)
Chondrocytes/drug effects , Methylphenidate/adverse effects , Attention Deficit Disorder with Hyperactivity/drug therapy , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Cells, Cultured , Humans , Methylphenidate/therapeutic useABSTRACT
PURPOSE OF THE STUDY Total knee arthroplasty is commonly used procedure with advanced stage arthritis which causes extensive blood loss intraoperatively and postoperatively. Purpose of this study is to show the effectiveness of sealing of femoral tunnel with bone grafting in preventing blood loss. MATERIAL AND METHODS 288 patients with primary bicompartmental knee arthroplasty who were operated in between April 2012 and June 2015 are retrospectively studied. Two groups are formed according to sealing of femoral tunnel with autologous bone graft or not. Group 1 was the plugged group with 192 patients and group 2 was the unplugged group with 96 patients. Operation time, arthrotomy method, anticoagulant therapy, postoperative care were similar in between two groups.'Independent sample t-test' is used to compare two groups as statistical method. RESULTS Postoperative lowest hemoglobin levels are higher in plugged group (p < 0.001). Drain outputs are much less than unplugged group (p < 0.001). There is no statistically significant difference between amount of given erythrocyte suspensions. DISCUSSION In the literature there are many attempts to reduce blood loss and allogenic blood transfusion. Some systemic or local usage of medical therapies, mechanical interventions such as cold application or intraoperative fibrin sealers are some of them. There are a few studies favoring usage of plugs and a few do not. Our findings showed less blood loss with usage of autologous bone grafting but did not significantly affect the blood transfusion amount. CONCLUSION Autologous bone grafting is a free to use, non-time consuming and an effective method to reduce blood loss. Key words: knee arthroplasty, plug, sealing of femoral tunnel, blood loss.
