Wear debris from articulating joint implants is inevitable. Small debris particles are phagocytosed by macrophages. Larger particles initiate the fusion of many macrophages into multi-nucleated giant cells for particle encasement. Macrophages are recruited into inflamed tissues from the circulating monocyte population. Approximately 10% of white blood cells are monocytes which after release from the bone marrow circulate for 2–3 days, before being recruited into tissues as inflammatory macrophages or undergoing apoptosis. Circulating MRP8/14 (S100A8/A9) is a measure of monocyte recruitment, part of the monocyte-endothelial docking complex, and shed during monocyte transmigration across the endothelium. The higher the S100A8/A9 the more monocytes being recruited giving an indirect measure of debris production. 2114 blood samples were collected from arthroplasty patients with hip or knee osteoarthritis (primary, post-traumatic and secondary), 589 before their primary arthroplasty, 1187 patients > 1 year post-arthroplasty, 101 patients before revision for aseptic loosening and 237 patients >1 year post-revision. Plasma S100A8/A9 was measured using BMA Biomedicals Elisa kit, normal levels in health adults are 0.5–3 mg/ml. Joint specific scores, WOMAC knee or Oxford Hip adjusted to percent of maximum, together with SF-12 were completed.Introduction:
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The risk factors for degenerative joint disease are well established: increasing age, obesity, joint abnormalities, trauma and overuse, together with female gender, ethnic and genetic factors. That obesity is a significant risk factor for developing osteoarthritis in non-weight-bearing as well as weight-bearing and joints was one of the first indications that the risk was nor purely that of aberrant biomechanical loading. Low grade chronic systemic inflammation is a component of each of ageing and obesity, atherosclerosis and diabetes, culminating in Metabolic Syndrome. In our study of 1684 patients with joint degeneration 85% were overweight or obese and 65% older than 65 years with 62% being both, 73% of patients were taking medications for serious, ‘non-orthopaedic’ health problems such as cardiovascular or respiratory disease, obesity or NIDDM. Monocytes are a major component of chronic inflammation, approximately 10% of white blood cells are monocytes which circulate for 2–3 days, before being recruited into tissues as inflammatory macrophages or undergoing apoptosis. Circulating S100A8/A9 (MRP8/14) is a measure of monocyte recruitment being shed during monocyte transmigration across the endothelium. The higher the S100A8/A9 the more monocytes being recruited giving an indirect measure of chronic inflammatory status. 2154 blood samples were collected from arthroplasty patients (first or second joint replacement), 1135 Female and 1019 Male, age 29–93 years, body mass index (BMI) 18–56, with hip or knee osteoarthritis (primary, post-traumatic and secondary), 589 before a primary arthroplasty, 1187 patients >1 year post-arthroplasty, 101 patients before revision for aseptic loosening and 237 patients >1 year post-revision. All study patients received metal on UHMWPE implants. Plasma S100A8/A9 was measured using BMA Biomedicals Elisa kit, normal levels in healthy adults are 0.5–3 mg/ml. The data were analysed using SPSS, p values were calculated using Spearman's test.Introduction:
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Shoulder motion results from a complex interaction between the interconnected segments of the shoulder girdle. Coordination is necessary for normal shoulder function and is achieved by synchronous and coordinated muscle activity. During rotational movements, the humeral head translates on the glenoid fossa in the anterior-posterior plane. Tension developed by the rotator cuff muscles compresses the humeral head into the glenoid fossa. This acts to limit the degree of humeral head translation and establishes a stable GH fulcrum about which the arm can be moved. Previous studies have been limited by the use of contrived movement protocols and muscular coordination has not been previously considered with regard to shoulder rotation movements. This study reports the activation profile and coordination of 13 muscles and 4 muscle groups during a dynamic rotational movement task based on activities of daily living. Eleven healthy male volunteers were included in the study. Electromyography (EMG) was recorded from 13 muscles (10 surface and 3 fine-wire intramuscular electrodes) using a wireless EMG system. EMG was recorded during a movement task in which the shoulder was consecutively rotated internally (phase 1) and externally (phase 2) with a weight in the hand. Muscle group data was calculated by ensemble averaging the activity of the individual component muscles. Mean signal amplitude and Pearson correlation coefficient (PCC) analysed muscle activation and coordination, respectively.Introduction
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