Compare And Contrast The Changes Described In

All The Tissue Types Of The Neuro-Muculoskeletal System Associated With Rheumatoid Arthritis And Degenerative Disease Accompanying Advancing Age. Essay, Research Paper

Compare and Contrast the Changes Described in all the Tissue Types of the Neuro-Musculoskeletal System Associated With Rheumatoid Arthritis and Degenerative Disease Accompanying Advancing Age.By Daniel Gibb (3rd Year)Introduction:Arthritis is a chronic illness frequently managed in the primary care setting. It is estimated that by the year 2020, 59.4 million, or 18% of Americans, will be afflicted with the disease.1 Arthritis in the United States is estimated to cost $54.6 billion, including medical treatment, work loss, and disability. It ranks among the top five causes of long-term disability2,There are more than 100 recognized types of arthritis, with osteoarthritis (OA) and rheumatoid arthritis (RA) being two of the most common.3 However, whilst rheumatoid arthritis is considered to be auto immunological in origin, osteoarthritis is associated with wear and tear or the aging process4. As such for the most part, the discussion of degenerative changes shall primarily focus upon osteoarthritis.Both osteoarthritis and rheumatoid arthritis affect various parts of the neuro musculoskeletal system. In order to clarify their comparison, it is necessary to investigate all parts of the neuro musculoskeletal system.Normal Joint Structure:The basis for both rheumatoid arthritis and age related changes or osteoarthritis is a breakdown in the normal structure and thus function of a joint or joints. A typified joint is shown in figure 1.Any disruption to one or more elements in the joint will lead to dysfunction in the joint. Thus the changes seen in patients with rheumatoid arthritis and osteoarthritis with respect to function occur.Figure 1: A Typified Joint. Synovial Fluid:In osteoarthritis, little, if any change occurs in the Synovial fluid filling the joint space. If however the osteoarthritic changes have intertwined with them, inflammatory action, white blood cell (WBC) proliferation may be present5. Also, the viscosity of the fluid may be raised above normal levels5.With rheumatoid arthritis, the changes in Synovial fluid constitution are far more abundant. The immunological nature of rheumatoid arthritis has the result of filling the Synovial space with an inflammatory infiltrate of lymphoid follicles (mainly CD4+ and helper T cells), plasma cells and macrophages5, 6. Again, as in degenerative forms of arthritis, the viscosity of the Synovial fluid may be increased. In rheumatoid arthritis and osteoarthritis, loose bodies are sometimes able to break away from the chondral or osseous surfaces of a joint. The fibrinocytes on the outer surface of the body derive nutrition from the Synovial fluid, thus proliferating. The center however becomes necrotic. In addition to Osseo-chondral bodies, excessive fibrous exudation into the joint may cause rice bodies in the joint (especially the knee), though this is more common in rheumatoid arthritis5.Synovium:The most blatant changes in the Synovium occur in rheumatoid arthritis. In this condition the membrane undergoes a polypoid fibrovascular thickening. This is to say that it the synoviocytes undergo hypertrophy and hyperplasia, occasionally with giant cell proliferation6. Vascular growth also abounds to meet the demands of the new, highly inflamed tissue. This will give rise to hyperaemia4, 5,6. Collectively this causes the Synovium to grow into a series of papillary folds, which may be traumatized in movement of the joint5.In osteoarthritic degeneration, the Synovium is not a primary site of degeneration6. Limited inflammatory changes may possibly be seen8. As such Synovial thickening is less common and a villous pattern may apply itself to the Synovium. This is generally due to absorption of abraded fragments of cartilage and bone9. However the fact that the fronds are more delicate is a sign of the lack of any great cellular infiltrate in the subsynovium5. The increase in vascularity seen in rheumatoid arthritis is not seen in osteoarthritis. If any change occurs in the vascularity of the Synovium of an aging joint, it is most likely to be a decrease due to the various age associated pathological mechanisms7.Capsule:In early osteoarthritis the joint capsule is largely spared due to its physical distance from the bony joint4. However, in later stages of osteoarthritis, osteophyte formation and joint effusion can have the effect of tightening the capsule8 (see figures 2 and 3).Figure 2: Joint changes in mild osteoarthritis. Tightening of the capsule will have the effect of restricting joint mobility and decreasing the blood supply and lymphatic drainage8.In rheumatoid arthritis the converse is true. Synovial infiltration may lead to destruction of the capsule5. This leads to instability and the inherent possibility of subluxation or dislocation and subsequent gross deformity5, 9. Cartilage:In early osteoarthritis, the primary changes are seen in the chondral surfaces of the joint. This is similar to those signs seen in the normal aging process10. The mechanism behind this is chiefly due to the avascularity of cartilaginous tissue and its low cell to matrix ratio and thus an inability to adequately repair damaged tissue11. Cartilage removal in osteoarthritis occurs mainly in the center or at the weight/ load-bearing portion of a joint12. Flaking and fibrillation of the cartilage a