Proteomic analysis of human osteoarthritis synovial fluid

Abstract Background Osteoarthritis is a chronic musculoskeletal disorder characterized mainly by progressive degradation of the hyaline cartilage. Patients with osteoarthritis often postpone seeking medical help, which results in the diagnosis being made at an advanced stage of cartilage destruction. Sustained efforts are needed to identify specific markers that might help in early diagnosis, monitoring disease progression and in improving therapeutic outcomes. We employed a multipronged proteomic approach, which included multiple fractionation strategies followed by high resolution mass spectrometry analysis to explore the proteome of synovial fluid obtained from osteoarthritis patients. In addition to the total proteome, we also enriched glycoproteins from synovial fluid using lectin affinity chromatography. Results We identified 677 proteins from synovial fluid of patients with osteoarthritis of which 545 proteins have not been previously reported. These novel proteins included ADAM-like decysin 1 (ADAMDEC1), alanyl (membrane) aminopeptidase (ANPEP), CD84, fibulin 1 (FBLN1), matrix remodelling associated 5 (MXRA5), secreted phosphoprotein 2 (SPP2) and spondin 2 (SPON2). We identified 300 proteins using lectin affinity chromatography, including the glycoproteins afamin (AFM), attractin (ATRN), fibrillin 1 (FBN1), transferrin (TF), tissue inhibitor of metalloproteinase 1 (TIMP1) and vasorin (VSN). Gene ontology analysis confirmed that a majority of the identified proteins were extracellular and are mostly involved in cell communication and signaling. We also confirmed the expression of ANPEP, dickkopf WNT signaling pathway inhibitor 3 (DKK3) and osteoglycin (OGN) by multiple reaction monitoring (MRM) analysis of osteoarthritis synovial fluid samples. Conclusions We present an in-depth analysis of the synovial fluid proteome from patients with osteoarthritis. We believe that the catalog of proteins generated in this study will further enhance our knowledge regarding the pathophysiology of osteoarthritis and should assist in identifying better biomarkers for early diagnosis. </jats:sec

Outcomes of total knee arthroplasty following high tibial osteotomy

BACKGROUND: Total knee arthroplasty (TKA) following high tibial osteotomy (HTO) is a technically demanding procedure with varying results. The purpose of our study was to analyze the clinicoradiological results of TKA following HTO and to identify the factors that may influence the final outcome. MATERIALS AND METHODS: 55 patients (58 knees) who had undergone a previous HTO were treated with a TKA from 1991 to 2009. There were 34 female and 21 male patients. The average age was 61.9 years (range 52-82 years) and the average weight was 79.5 kg (range 54-106 kg), with an average body mass index of 29.6 (range 21.8-34.6) at the time of TKA. The knee society scores (KSSs) and knee society functional scores were evaluated for every patient pre and postoperatively and the results evaluated. RESULTS: The mean period of followup was 11.2 years (range 3-18 years) and the patients were followed up every year. The average KSS score at final followup improved from 38.5 (range 0-80 points) preoperatively to 88.5 postoperatively (range 35-95 points) (P < 0.05). The mean femorotibial angle corrected from 6.8 degrees (range 5-12°) varus preoperatively to a valgus of 4.4 (2-8°) degrees postoperatively. The average joint line height improved to an average of 9.6 mm (range 4.4-22 mm) (P < 0.01) at the last followup. The average Insall Salvatti Ratio also improved (average 1.11 preoperative - 1.21 average postoperative) (P < 0.05). The average range of motion improved to 108° (range 85°-125°) from 76° preoperative (range 55°-100°) (P < 0.01). CONCLUSION: Although TKA postHTO is a demanding surgery however, with newer component designs, results are comparable to primary TKA. Technical difficulties in exposure can sometimes lead to component malpositioning, which can affect the final outcome. Inadequate soft tissue balancing and limb malalignment should always be kept in mind. Regular followup to look for evidences of loosening is advised in such patients]

Revision Total Knee Arthroplasty for Septic versus Aseptic Failure

Purpose.To compare the medium-term outcome of revision total knee arthroplasty (TKA) for septic versus aseptic failure.Methods.Records of 142 patients who underwent revision TKA by a single senior surgeon for septic (n=65) or aseptic (n=77) failure were reviewed. In the septic group, 67 knees in 42 women and 23 men were included. In the aseptic group, 88 knees in 51 women and 26 men were included. The Knee Society Score was measured. The Kaplan Meier survival curve at months 36, 60, and 95 was plotted, with revision as the end point. The survival rates at each specific time point between the 2 groups were compared using the Z test.Results.The Knee Society Scores improved 18% from 51 to 69 in the septic group and 18% from 52 to 70 in the aseptic group (p=0.72). The range of motion improved 30% from 72° to 102° in the septic group and 39% from 62° to 100° in the aseptic group (p&lt;0.001).Conclusion.Results of the 2 groups were similar in terms of the Knee Society Score, range of motion, and the Kaplan-Meier survivorship.</jats:sec