Osteoarthritis of the Knee
It is defined as a degenerative ,non_ inflammatory joint disease characterized by destruction of articular cartilage and formation of new bone at the joint surfaces joint disease.
Osteoarthritis (or) de generative joint disease.
Osteoarthritis affects the synovial joints, through it can affect any joint, it is more common in the weight bearing joints like the hip, knee , spine etc.
Exact cause is not known, the following factors are suspected to play an important role in the causation of primary O.A __ obesity, genetics and heredity, occupation involving prolonged standing sports, multiple endocrinal disorders and multiple metabolic metabolic disorders .
● This is Idiopathic and forms 50% of the O.A of the hip.
● In this variety, the exact cause is not known and the causative factors suspected are increased anteversion and trabecular microfracture causing stiffening of the subcondral bone.
● Incongruity of the articular surface: ( eg. Trauma, CDH, slipped epiphanies).
● Instability of the hip: (e.g subluxation )
● Concentration of pressure load:( e.g. coxa vara, anteversion).
● Direct injury:( e.g infection, trauma etc.)
● Constitutional causes:( e. g. Obesity , hyperthyroidism etc.)
● Bone diseases like( AVN( avascular necrosis) , Rheumatoid arthritis etc.)
● Older age
● Obesity
● Genetics
● Repetitive stress & mechanical overload
● High impact sports(e.g. foot ball,hand ball, hockey,weight _ lifting,long _ distance running).
● Changes in articular cartilage.
● Synovial is thick and congested .
● The subchondral bone shows sclerosis & cyst formation.
● The capsule is thick and fibrosis.
● New bone growth results in osteophyte formation in areas not under pressure.
Osteoarthritis of Other Regions:
● It is usually seen in the elderly age group and the patient presents with low backache.
● Osteophytes may compress the nerve roots at their exit at the intervertebral formed and may cause neurological disturbances.
● O.A may affect the peripheral joint of the hand & foot.it may cause ankylosis at an increased rate in these joints.
