Results: Out of the 4911 patients in the TReasure database, sacroiliac joint MRI and/or cervical and lumbar lateral radiographs were available for 1381 patients. One hundred and ten patients were selected as a matched control group based on the disease duration of patients with a bamboo spine.

The demographic and clinical features of these patients were recorded. Group-1 consists of patients with a bamboo spine, Group-2 consists of patients with bridging (advanced radiographic involvement) bridging of two vertebrae in a row, Group-3 consists of patients with syndesmophytes in at least one vertebra, and Group-4 consists of patients with no syndesmophytes. Patients with complete cervical and lumbar x-rays were divided into three groups. axSpA patients fulfilling the ASAS classification criteria (Sacroiliitis defined either according to the mNY- or ASAS positive MRI criteria) were analyzed. This database contains 4911 SpA patients using bDMARD therapy. Methods: TReasure is a multicentre database, started in December 2017, in which clinical and demographic data of inflammatory arthritis patients using biological and synthetic DMARDs are recorded (1). This study aims to investigate the possible risk factors associated with the bamboo spine in axial Spondyloarthritis (axSpA) patients treated with biological DMARDs. Sadi Konuk Training and Research Hospital, Bolu, Turkey, 7Hacettepe University, Faculty of Medicine, Department of Internal Medicine, Division of Rheumatology, Ankara, Ankara, Turkey, 8Eskisehir Osmangazi University, Faculty of Medicine, Department of Internal Medicine, Division of Rheumatology, EskiЕџehir, Turkey, 9Trakya University, Faculty of Medicine, Department of Internal Medicine, Division of Rheumatology, Edirne, Turkey, 10University of Health Sciences, Gulhane Faculty of Medicine, Department of Internal Medicine, Division of Rheumatology, Ankara, Turkey, 11Hatay Mustafa Kemal University, Faculty of Medicine, Department of Internal Medicine, Division of Rheumatology, Hatay, Turkey, 12Akdeniz University, Faculty of Medicine, Department of Internal Medicine, Division of Rheumatology, Antalya, Turkey, 13Ankara University, Ankara, Turkey, 14Ministry of Health Adana City Hospital, Adana, Turkey, 15Sakarya University, Department of Internal Medicine, Division of Rheumatology, Sakarya, Turkey, 16Tekirdag Namik Kemal University, Faculty of Medicine, Department of Internal Medicine, Division of Rheumatology, TekirdaДџ, TurkeyД«ackground/Purpose: Complete ankylosis of the entire spinal column is a severe condition seen in spondyloarthritis. Pamir AtagГјndГјz 1, Sedat Kiraz 2, Servet Akar 3, Orhan KГјГ§ГјkЕџahin 4, Abdulsamet Erden 4, Nihan CoЕџkun 5, Burcu YaДџД±z 5, Cemal Bes 6, Levent KД±lД±Г§ 7, Г–mer KaradaДџ 7, TimuГ§in KaЕџifoДџlu 8, Hakan Emmungil 9, Muhammet Г‡Д±nar 10, GezmiЕџ Kimyon 11, Veli YazД±sД±z 12, Askin Ates 13, Emine Duygu Ersozlu 14, Emel GГ¶nГјllГј 15, RД±dvan Mercan 16, Д°hsan Ertenli 2 and Umut Kalyoncu 2, 1Marmara University, Faculty of Medicine, Department of Internal Medicine, Division of Rheumatology, Д°stanbul, Turkey, 2Hacettepe University, Faculty of Medicine, Department of Internal Medicine, Division of Rheumatology, Ankara, Turkey, 3Izmir Katip Celebi University, Izmir, Turkey, 4YД±ldД±rД±m BeyazД±t University, Faculty of Medicine, Department of Internal Medicine, Division of Rheumatology, Ankara, Turkey, 5Uludag University, Faculty of Medicine, Department of Internal Medicine, Division of Rheumatology, Bursa, Turkey, 6Bakirkoy Dr.

Bamboo spine