"Waiting times in orthopaedics shocking"

I was seen in clinic on 14th October 2014 by a doctor who put me on the list for knee surgery. I was called on 17th Feb to be given a date of March 5th at Methley Park. On the 25th Feb I got a call saying this has been cancelled, and to wait for another date as March was full. I called waiting list team on March 26th to be told April is full, and they said it could be May. This means I will have been waiting for over 31 weeks for a operation date. My situation is leaving me in more pain and I'm feeling let down by Pinderfields.