This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Skeletal infections, Subject name: Orthopaedics
Triple deformity of knee joint is seen in 
Select and explain. 
A. Tuberculosis, B. Trauma, C. Malignant tumour, D. Sarcoidosis
A: Tuberculosis
Answer: A: Tuberculosis 
Explanation: TB KNEE has two stages. In late stage it shows TRIPLE DEFORMITY- Posterior Subluxation External Rotation Flexion Other condition showing triple deformity of knee-Rheumatoid Ahritis REF : MAHESWARI 9TH ED