This study is testing two products, *MagnetOs Putty* and *MagnetOs Easypack Putty*, used to help fuse bones in the foot or ankle. Fusing means connecting bones together using special materials. Doctors often use these products instead of taking bone from another part of the body, called an autogenous bone graft.

In this trial, 126 patients will get either MagnetOs or an autograft, along with metal plates or screws to keep bones in place during healing, a process called *arthrodesis*. Patients will be checked at various times up to a year after surgery to see how well the products work. They’ll have X-rays and CT scans, which are special pictures of the inside of the body, to see if the bones are fusing well.

Eligible patients are adults who need specific foot or ankle surgeries. They must be able to understand and agree to the study rules. People with certain health problems or previous surgeries on the same area may not be able to join.

• Study lasts about a year with regular check-ups.
• No compensation mentioned for participants.
• Risks involve surgery and potential follow-up interventions.