Bone grinding and lost range of motion

Dear Sir, I am 37 and have been in the Air Force for 19 years, My Rt knee has been scoped 3 times since age 22, "first time for severe locking" each subsequent procedure was for the locking but not as severe and after every procedure I'm told that they didnt find anything significant, 3 weeks ago I was playing softball, "only batting and pitching; no hard running" my knee feels like bone on bone and the range of motion is greatly reduced. I have been living with some discomfort since age 22, but my knee is not responding to anything that I normally do. Stay off it, wear a elastic brace. I really would like to get my knee fixed before I retire from the service, I would like an Expert opinion from someone other than the "Company Man". It will be up to me to talk them into letting me get help from a professional sports Orthopedic Doctor, and after all that I seen and heard, I truly believe you guys are the only ones that can help. Thank You