Young man with lower back pain and awaiting MRI results

Dear Ask The Doctor: I am impatient for my MRI results, and trying to get answers pertaining to back injury. I am in a special operations training program, and cannot reveal all symptoms to doctor. If there is permanent damage - I'm out, but if it's a strain that I can just gut out...then I will push through until completion. We have excellent benefits, but due to the army's downsizing...I worry if my career is on the line. My back has hurt for the last 18 months. I run about 20 miles a week, and ruck-run (which is terrible for joints, i am aware. not given a choice in the matter) with 55 lbs for 6 - 12 miles. The lower the distance, the faster the pace. The 6 miler is harder, because an 11 minute mile pace is kept. I can run and ruck, there is only minor pain. A 3 out of 10. Throughout the day, and that evening is usually absolute misery. My feet were going numb a few months ago, but that subsided. I had a very bad parachute landing 3 months ago. Had a sprained ankle, but needed to complete the jump. Landed on my back to save the ankle increased damage. I kept pushing through. Some days are better than others. Feel as though I have a high pain tolerance. Being an amateur MMA fighter, and former college lacrosse player has definitely added some mileage to my body. The PA that has seen me isnt sure. Degenerative disc disease is suspected, because radicular symptoms are no longer present. It hurts to sit in one position for longer than 60 seconds. It hurts to stand in one place, and my spine cracks at will when i merely straighten my back. I can bend forward to about where my back is perpendicular to the ground, and there is a dull pinch in my whole lumbar area. Twisting is painful. Laying down on my back is too painful to sleep. I sleep on my left side with a pillow between my knees, and still wake up throughout the night to adjust. While I've been dealing with this, I've read a fair amount of information. My symptoms don't seem to really lead me to any specific problem. It was easy to ignore for so long, because it hurts much much worse when I'm NOT doing an activity. I'd rather run than sit on the couch, because the pain is worse sitting down. I'm hoping it's just a strain. Had to ask my own question, because the majority of info and answered questions are for the sedentary middle aged office worked. I am a 26 year old combat veteran. If the injury is serious, I understand my health is not worth career progression. If it is not too bad though, pain is temporary. ANY insight would be appreciated.

Dear Jeremy: I suggest that do not jump into conclusions before to know the findings, meaning the results of the MRI. There are other possibilities that may produce lower back pain and with physical therapy, weight control and posture hygiene they evolve very good. Besides the degenerative disc disease , the Lumbar facet arthropathy is one of the causes of chronic low back pain, but is usually not considered until conservative measures for treating low back pain (LBP) have been tried without success or an MRI confirm the diagnosis. The facet joints in the spine suffer degenerative changes or “arthritis”. This may be due to: wear and tear (that produces narrowing of the space between vertebrae and the facet joints start to rub together); previous back injury; torn spine ligaments; disc problems. With time, bone spurs may develop and the cartilage may also suffer deterioration. But, as I told you before wait the results and do not jump into conclusions.