This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Congenital Dislocation of Hip (C.D.H.), Subject name: Orthopaedics
Triple deformity of knee joint seen in : 
Select and explain. 
A. Tuberculosis, B. Trauma, C. Malignant tumor, D. Sarcoidosis
A: Tuberculosis
Answer: A: Tuberculosis 
Explanation: Ans. is 'a' i.e. Tuberculosis In early stages of TB knee, there is mild flexion deformity of the knee because of effusion in the knee and the muscle spasm. Later triple displacement occurs due to ligament laxity .This includesFlexionPost subluxation of tibiaExternal rotation of tibia.