Crohn's disease & metabolic bone disease. is there a relation?

Yes: People who have long standing history of crohn's may develop metabolic bone disease . This is in part due to malabsorption of important vitamins and minerals like vitamin d and calcium but could also be secondary to the prolonged use of steroids which can also results in metabolic bone disease manifested as osteoporosis.

Yes it is: Crohn's and ulcerative colitis are associated with metabolic bone problems, such as osteoporosis. This is worsened by frequently using steroids.

Yes: with failure to absorb vitamin D and/or calcium!

Yes: Yes, potentially by three mechanisms: first, a percentage of patients with Crohn's disease will have an inflammatory arthritic component to it that can affect the bones; second, patients with Crohn's can have malabsorption of some of the key nutrients that make bone string; and third, some of the medications used to treat Crohn's can impact bone health. Discuss with your doctor.