Patients diagnosed with inflammatory bowel disease (IBD) often develop one or more extraintestinal manifestations (EIM). We performed a prospective study that included 517 patients with IBD (Crohn's disease - CD, ulcerative colitis - UC or undifferentiated colitis - CN) diagnosed between 1975 and 2016 in the Northeastern region of Romania. The patients were extracted from the national database (IBD Prospect). UC cases predominated compared to CD cases (n=368 vs. n=135). Only 10 patients were diagnosed with CN. In the study group, 51 cases with IBD and EIM were identified, having a prevalence of 9.9%. Musculoskeletal manifestations were the most common EIM. Peripheral involvement - arthritis (n=26, 68.42%) predominated, followed by axial damage - sacroiliitis/ankylosing spondylitis (SI∕AS) (n=12, 31.58%) (p=0.001). Patients with CD had a 3.48-fold greater risk of developing joint manifestations [p<0.001, odds ratio (OR)=3.478, 95% confidence interval (CI) 1.779-6.801]. In both CD and UC patients, arthritis cases were the most frequent observed (68.42% vs. 31.58%). Patients with CD had a 5-fold higher risk of developing arthritis (p<0.001, OR=5.009, 95% CI 2.21-11.34). Neither CD, nor UC patients, had a confirmed risk of developing SI∕AS (p=0.468, OR=1.565, 95% CI 0.463-5.293 for CD) (p=0.586, OR=0.714, 95% CI 0.211-2.413 for UC). Cases of arthritis and CD (n=16) mainly correlated with the colonic localization of inflammation (n=7, p=0.723) followed by ileo-colonic form of CD (n=7, p=0.321). Patients with arthritis and UC (n=10) initially correlated with pancolitis (n=5, p=0.072, OR=3.023, 95% CI 0.855-10.69) then with proctitis (n=3, p=0.392) and left-sided colitis (n=2, p=0.024, OR=0.196, 95% CI 0.041-0.938).