My partner also suffered with PN due to his diabetes, he was already taking ACV and CO, this seemed to help his blood sugars , but not the pain.
However literally after the first dose of MSM he got instant relief, he continues to take it but rather on an if and when need basis. Also we read that LECITHIN can help, which he also takes, daily, due to a relative short shelf life. He is so much better.!!! Oh I hope this helps , any one that suffers this puts up with so much.:(.