<prompt> Most common part of spine affected by Rheumatoid arthritis is?Lumbar spineThoracic spineCervical spineSacrum  <response>: Ans. c Cervical spineRef..MR Imaging of the Spine and Spinal Cord by DetlevUhlenbrock p-375, Orthopedic surgery essentials- Spine by Christopher M. Bono, Steven R. Garfin p-188 