OSTEOARTHRITIS

OSTEOARTHRITIS: A leading cause of disability

0steoarthritis is a common ,slowly progressive disorder affecting the synovial joints and the weight bearing joints[eg. Knee & hip joints]of the peripheral and axial skeleton. Inflammation may not be present in the affected joints,though it is mostly seen in the age group of above 65 years; where as 80% have radiographic features ;and 25-30% have symptoms. Most common in womens after at the age of 55,however osteoarthritis occurs equally in men and women, which is mostly related to natural aging.

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ETIOLOGY:

As osteoarthritis includes bone, joint and inflammation which is a disease involving the inflammation of bone and joint cartilage.The main cause of the osteoarthritis include excess body weight, muscle with lack of strictness, joint deteoriation or the previous joint injuries. As with aging the water content of the cartilage increases and the protein of cartilage degenerates due to which the bones rub together and causes pain, swelling, and stiffness and the extra bone forms around the joint and the ligaments around the joint becomes weaker and stiffer.

RISK FACTORS:

■ Osteonecrosis 

■ Advancing age

■ Being over weight increases the risk in the hip, knee, ankle, and foot joints 

■ Fractures or other joint injuries can lead to osteoarthritis which includes injuries to the cartilage and ligaments in joint.

■ Jobs that involves kneeling, squatting for moe than an hour in a day put you in high risk and also including lifting, climbing stairs, or walking .

Medical conditions that can lead to osteoarthritis include:

■ Bleeding disorders that causes bleeding in the joint, such as haemophilis

■ Disorders that block blood supply near a joint and lead to avascular necrosis[osteonecrosis]

■ Other types of arthritis, such as cronic gout, pseudogout.

PATHOPHYSIOLOGY;

        A primary idiopathic osteoarthritis ,not resulting from injury or disease, is a result of natural aging of the joint,with aging and also cartilage increases with water content,which is common type that has no known cause subclass of primary osteoarthritis are termed as localized osteoarthritis which involves one or two sites and generalized osteoarthritis which going to affect three or more sites.The term erosive osteoarthritis is a progressive disease affecting the interphalangeal joints of the hand,also known as inflammatory form of osteoarthritis which includes pain, swelling, redness, warmth which are proliferated in proximal and distal interphalangeal hand joints.

where as the secondary osteoarthritis is associated with the known cause as rheumatoid arthritis, trauma, metabolic endocrine disorders and birth defects[congenital factors].

Osteoarthritis damage the articular cartilage through injuries loading from obesity or joint instability injuries that causes abnormal loading, and damage to cartilage increases the metabolic activity of the cells found in the healthy cartilage leading to maintain the cartilaginous matrix.

Initial event in osteoarthritis; mitosis of chondrocyte with increased synthesis of the proteoglycans[core protein ]and type ii collagen takes place with decrease in concentration of proteoglycans in the chondrocyte.

Second event; Increase in the synthesis of bone by osteoblasts in the subchondral bone by intercommunication between chondrocyte and osteoblasts in the subchondrial bone cells, with increased bone formation in the subchondral area, physical change and the bone become stiffer and microfractures occurs, these microfactures produces callus which is a connecting bridge across a bone fracture during repair,hence it is stiff.

Third event; The change in the cell type in the peripheral synovial cells results in formation of combination bone, connective tissue, fibrocartilage and hyaline cartilage on the surface.

Fourth event; Formation of bony cysts takes place mostly pseudocysts below the subchondral bone,where the mechanism involves the extrusion of joint fluid through the hyaline cartilage into osteoblstic cellular reaction around the synovial fluid

MACROSCOPIC MANIFESTION OF OSTEOARTHRITIS include loss of surface of hyaline cartilage, pitting, and diffuse area of loss of cartilage surface , proliferation of new bone, cartilage.

 

 DIAGNOSIS;

■ Joint movement may cause cracking sound 

■ Joint swelling

■ Tenderness when the joint is pressed

■ Normal movement is often painful

An x-ray of affected joints will show a loss of joint space.

TREATMENT;

■ Educate the patient about the disease and maximum weight-loss program are recommended for overweight osteoarthritis patients.

■ Physical measures: exercise ,supportive devices such as canes, walkers, heel cups can be used during exercise or daily activities.

■ Surgical procedures such as osteotomy , joint fusion are indicated for patients with functional disability and or during severe pain

PHARMACOLOGICAL THERAPY

■ For mild or moderate pain topical anaesthetics or acetaminophen is used and if any fail or inflammation NSAIDs are used.

■ Topical agents such as capsacicin , toipical NSADs are used.

 

                                          

                                                                                                                           D. Yamini Sai Nikitha

                                                                                                                                     B.pharmacy