Endogenous:

• Monosodium urate – Gout

  Gout

• Calcium pyrophosphate – Pseudo Gout.

  Pseudo Gout

• Calcium phosphate: erosive arthropathies, Osteoarthritis etc.

• Calcium oxalate: Renal failure.

Exogenous:

• Corticosteroids: Therapy induced.
• Silicone, polyethylene etc. in prosthetic joints cause arthritis