Heredity

Hormonal and sex factors. 

Severe or recurrent joint injury from heavy physical activity

Excessive mobility/joint instability. 

Skeletal postural defects

Age-related changes in collagen matrix repair mechanisms. 

Excess overweight-excessive body weight and high body mass index are significant predictors of osteoarthritis of the knee.

Fractures and mechanical damage.

Exercise- activities such as long-distance running, basketball, etc. performed over many years will result in the development of arthritis.

Cold climate and atmospheric pressure changes

Inflammation.

Food allergy - common causes are nightshades (potatoes, tomatoes, peppers, and eggplants), wheat, and dairy

A diet high in animal products

Altered biochemistry.

Nutrient deficiency: calcium, magnesium, manganese, protein, essential fatty acids

Inflammatory joint disease.

Low-grade infections (e.g., dental infections) and autoimmune disease

Dehydration

Excessive acid in the body causing increased amounts of calcium, minerals, and acid toxins to be deposited in the joint, resulting in inflammation and pain

Other systemic disorders often associated with arthritis include nutritional deficiencies, digestive disorders, constipation, fatigue, emotional stress, and endocrine disorders