Arthritis

Introduction
Cause and Pathogenesis
Symptoms and Signs
Investigations and Diagnosis
Treatment and Prognosis
Prevention

Arthritis is a chronic degenerative disease that affects the joints of the body. There are two main types:

• Osteoarthritis, which is a chronic degenerative disease process occurring mainly in the hips and knees and is characterized by a deterioration of the joint cartilage, formation of a new bone in the joints and joint hypertrophy (increase in size of the joint).
• Rheumatoid Arthritis, which is a chronic systemic degenerative disease characterized by inflammation of the connective tissues and manifests mainly in and around peripheral joints of the body.

The cause of osteoarthritis is not known, but is believed to be related in some way to ageing and genetic factors. The water content of the hyaline cartilage in the joint increases, and the protein-carbohydrate molecules present in the cartilage decreases. The cartilage becomes softer and weaker, loses resilience and elasticity and sheds flakes into the joint. The shedding erodes away the cartilage and increases the friction in the joint, setting up an erosive cycle. As the cartilage erodes, the underlying bone is consequently exposed. Fibrous tissue then forms in the joint capsule, causing inelasticity and the limitation of joint movements. New bone, which is formed in the affected area and at the joint margins, is stiff and subject to microfractures. Deterioration of the weight-bearing surface of the joints together with the bony overgrowth then leads to joint hypertrophy (overgrowth) and deformity.

During the early stages of Osteoarthritis, the symptoms consist of a deep aching pain in the joint that is aggravated by exercise and that worsens during the day. Inactivity results in stiffness of the joints. The intermediate stages are characterized by reduced joint movements, tenderness, crepitus, (crackling noises on movement), grating sensation of the bones, joint swelling and enlargement. In the later stages of the disease, the symptoms are mainly tenderness on palpation of the joints, pain with passive range of motion, increase in severity and duration of the pain, deformities of the joint and subluxation ( partial dislocations of the joint).

The early stages of rheumatoid arthritis consists of nonspecific symptoms like fatigue, malaise, mild fever, weakness, weight loss. The symptoms of the intermediate stages include tenderness and pain, stiffness in the affected joints (most often the fingers that occurs in a bilateral, symmetric pattern and spreads to the wrists, elbows, knees, and ankles), reduced joint function, numbness, and joint deformities. Later stage symptoms include nodules that form below the skin (subcutaneous rheumatoid nodules), ulcers on the lower limbs, enlargement of lymph nodes (Lymphadenopathy), inflammation and dryness of mucous membranes, cardiac disorders, enlargement of the spleen (Splenomegaly), etc.

Clinical diagnosis of osteoarthritis is made on the presence of any of the above mentioned symptoms or the presence of nodules (Heberden's or Bouchard's nodules) on the finger joints. Analysis of gait shows altered or abnormal motion patterns. Radiological examination (X-Ray) shows a narrowed joint space, increased density of subchondral bone, the presence of pseudocysts in the subchondral marrow, and osteophytes at joint periphery, etc. The Erythrocyte Sedimentation Rate (ESR) is normal or shows a moderate increase. Synovial analysis shows a high viscosity, yellow transparent colored fluid, WBC count is elevated with the presence of Polymorphonuclear Leukocytes (a type of white blood cell).

Clinical diagnosis of rheumatoid arthritis is made on the presence of five or more of the following symptoms - morning stiffness of joints, pain or tenderness in at least one joint, swelling in at least one joint, symmetric joint swelling, fatigue, weakness, weight loss, paresthesia, Raynaud's Syndrome, and subcutaneous nodules. Major organ involvement may lead to Pericarditis, Valvular Lesions, Vasculitis, Pneumonitis etc. Fibrosis, Tenosynovitis, Ankylosis, Felty's Syndrome (Splenomegaly And Leukopaenia), joint deformities etc. may also be seen. The Rheumatoid factor is positive in a number of cases. Synovial analysis shows an opaque color of the fluid, increased volume and turbidity, decreased viscosity and complement, elevated WBC count with a predominance of polymorphonuclear cells. Erythrocyte Sedimentation Rate (ESR) is elevated in a majority of cases. Complete blood count shows Hypochromic Anaemia and elevated WBC count. Radiology shows soft tissue swelling, narrowed joint space and marginal erosions. Additional tests to check for other autoimmune diseases are also done.

Treatment for Osteoarthritis includes exercises like strengthening, stretching, balancing and other motion exercises, rest, massage and moist heat for pain, elastic bandages for support, prosthesis walkers to aid mobility, use of a firm bed and hard chairs, and use of sturdy, low-heeled shoes. Drugs like Aspirin, Nonsteroidal Anti-Inflammatory drugs, and muscle relaxants are effective. Surgical intervention like Osteotomy, laminectomy, fusion, total joint replacement can be done if conservative therapy is not effective. Complications of osteoarthritis include involvement of the spine which can cause compression of the spinal cord leading to weakness in the extremities, incontinence of bowel and bladder, and impotence.

Treatment for Rheumatoid Arthritis includes moist compresses to reduce pain and oedema, therapy and exercise to increase range of motion, strength, and endurance, balance of activity and rest, prosthesis and walkers to aid mobility, and counseling to adapt to disability. Drug therapy includes Aspirin, Nonsteroidal Anti-inflammatory drugs, Gold Compounds or Penicillamine to reduce pain and inflammation, oral or intra-articular injections of Corticosteroids to reduce inflammation, and Immunosuppressive or Antineoplastic agents. Surgical intervention includes Synovectomy for pain relief, repair of ruptured tendon sheaths to prevent deformity and dislocations, Osteotomy to change weight-bearing surfaces, and joint replacement to increase the joint mobility. Complications of Acute Rheumatoid Arthritis (ARA) include a sudden onset, and a progressive deterioration of the joint and the involvement of other major systems with poor response to medical treatment.

The prevention of arthritis is difficult as there are very few known, preventable causative factors. Adequate exercise and proper diet may help to mitigate the effects of the disease to some extent. Prompt diagnosis and treatment is most essential to prevent complications. Counseling and physiotherapy for the affected patients is also essential.