This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: All India exam, Subject name: Orthopaedics
Which of the following is a feature of triple deformity of the knee joint? 
Select and explain. 
A. Posterior subluxation of tibia, B. internal rotation of tibia, C. Medial angulation of tibia, D. Recurvatum
A: Posterior subluxation of tibia
Answer: A: Posterior subluxation of tibia 
Explanation: Triple deformity of knee refers to:-Flexion of kneeExternal rotation of the tibiaPosterior subluxation of the tibiaThe triple deformity is seen in RA, TB of knee and Polio(Refer: Mohindra's Fundamentals of Ohopedics, 2nd edition, pg no. 528)