In order to fix the patient; fix their life:
Lifestyle management is essential. Diabetic control is key and regular HBA1C monitoring is something that must be chased up. Additionally managing your cardiovascular risk factors and cutting down on smoking is all supportive in the long-term management and prevention of OM.
When it comes to IVDU patients the drug use is a symptom, not a disease in its own right. Psychiatric support from addiction services and early involvement of social workers can be transformational patients with chaotic lifestyles.
Ultimately though you can only treat the patient as much as they want to be treated and as a doctor you can offer treatment not force it on them. A lot of people are not at the appropriate point in the cycle of change for you to push and push, indeed it can alienate them further, and you need to be understanding of that. Yes, it's frustrating and sometimes we all want to go in all guns blazing however for a lot of people that isn't appropriate.