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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
A most common cause of bony ankylosis-
assistant
The correct answer is  Ankylosis

Ankylosis is the fusion of bones in a joint leading to stiffness of the joint.
Ankylosis may be : -

1) Fibrous ankylosis: - Two articular surfaces are fused by fibrous tissue.
The feature are : -

Some movement of joint is possible (though just a jog of movement).


Movements may be painless or painful.
Most common cause is tubercular arthritis.


2) Bony ankylosis: - There is a bony union between two articular surfaces. The features are : -

No movements possible.
a Joint is painless
A most common cause is acute suppurative arthritis (septic arthritis).
Sometimes, stiffness may also occur due to extra-articular etiology such as in Bum contracture, myositis ossificans etc. It is called False ankylosis.