This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Peripheral nerve injuries, Subject name: Orthopaedics
what is the Most common cause of tarsal tunnel syndrome ? 
Select and explain. 
A. Osteoahritis, B. Ankylosing spondylitis, C. Psoriatic ahritis, D. Rheumatoid ahritis
D: Rheumatoid ahritis
Answer: D: Rheumatoid ahritis 
Explanation: Tarsal tunnel syndrome - the syndrome occurs due to compression of tibial nerve within the fibrous osseous tunnel under the flexor retinaculum of ankle joint .This is associated with pain & parasthesia in the sole of the foot often worse at night. ref : maheswari 9th ed