[Breathless Horror]

"Well for starters tell him to stop fucking cracking his back using lever force. Second, he needs to treat for inflammation. A topical anti-inflam ointment would probably really help reduce his symptoms. If he gets sharp pain with specific movement he should go to see someone. A good osteopath or chiropractor would be my first choice. Otherwise the standard battery of protect, rest, ice, compress and elevate applies."

Thus spake the physiotherapist in training. Hope it helps dude.