This problem is due to a possible infection in the bone with decreased blood supply leading to non union.
If possible, kindly share the x ray and clinical images of the limb for better understanding of the problem.
Next Steps
Primary management in this situation will be to control the infection.. If there is any dead bone, it should be removed.
Health Tips
Take high protein diet, antibiotics for infection control, analgesic,
calcium and
vitamin d supplement..