<prompt> Rheumatoid arthritis commonly affects the -Cervical spineThoracolumbar spineLumbar spineSacral spine  <response>: Ans. is a i.e., Cervical spine o In decreasing frequency, the metacarpophalangeal MCP, wrist, proximal interphalangeal PIP, knee, metatarsophalangeal MTP, shoulder, ankle, cervical spine, hip, elbow and temporomandibular joints are most commonly affected. 