This study investigates the risk of bone fractures in patients with chronic kidney disease (CKD). People with kidney failure often have a higher chance of hip fractures, but usual bone scans don't predict these well. New MRI methods have been developed to study the water in bones, which is important for understanding bone health. Bone contains two types of water: one that is part of the bone and another that fills small holes in the bone. In CKD patients, these holes may be larger and filled with more water. The study uses a measure called the porosity index to estimate the water in these holes compared to the water attached to the bone.

Participants will undergo MRI scans to measure the porosity index. This involves using MRI technology to see how much water is in the bone and how much is in the holes of the bone. By comparing these measurements, researchers hope to better understand the risk of fractures in people with CKD.

• Who can participate: Men and women aged 21-50 years with severe chronic kidney disease (stage 4 CKD) or healthy controls matched by age, ethnicity, diabetes status, and BMI can participate.
• Study details: Participants will undergo MRI scans to measure bone water content. Healthy participants will assist in developing the MRI protocol.