1. Resnick D: Rheumatoid arthritis and the seronegative spondyloarthropathies: radiographic and pathologic concepts. In In Diagnosis of Bone and Joint Disorders, edn 4. Edited by Resnick D. Philadelphia: W.B. Saunders Company; 2002:837–890. Provides an excellent overview of imaging similarities and differences between RA and spondyloarthropathies.
2. Zeidler H, Mau W, Khan MA: Undifferentiated spondyloarthropathies. Rheum Clin North Am 1992, 18:187–201.
3. Shaibani A, Workman R, Rothschild BM: The significance of enthesopathy as a skeletal phenomenon. Clin Exp Rheumatol 1993, 11:399–403.
4. Braun J, Bollow M, Sieper J: Radiologic diagnosis and pathology of the spondyloarthropathies. Rheum Dis Clin North Am 1998, 24:697–735.
5. Resnick D: Ankylosing spondylitis. In Diagnosis of Bone and Joint Disorders,edn 4. Edited by Resnick D. Philadelphia: W.B. Saunders Company; 2002:1023–1081. An excellent review of ankylosing spondylitis.