Its from years of heavy lifting, I have had disc replacement and nerve damage. My discs were reduced in height due to firstly compression injuries from Rugby, then years of heavy lifting. Before teh surgery I lost my right side from the nerve being clamp from vertebrae, where the disc height had been worn down, this effected my whole right side much in the way Ronnie left side has gone, four years on, its still not corrected, it did improve, but I would never be able to grow evenly again, real issue with my back as uneven lat mass can cause spinal issue due to the lack off evenness. I notice the symptoms in so many bodybuilders Jays going that way as well, first thing to go is the triceps, its a bitch and theres no coming back from it.