First, and underlying case of mild to moderate degenerative disc disease. DDD is common in many people, who are usually asymptomatic, until a trauma like yours aggravates the condition.
Second, you have a disc protrusion at the bottom of the spine which is placing pressure on the nerve roots forming the sciatic nerve -- a large nerve that travels through the buttocks down the leg.
Pain from the buttocks through the knee from this kind of low back condition is known as sciatica.
Surgery is an option but can aggravate pain. It is best to leave surgery as a last resort until more conservative means have been exhausted.
I suggest that you consult with an interventional spine and pain physician. This is an MD or DO with the credential DABPM, which means they are board certified in pain management. This practice, and advanced practice of anesthesia, can often deal effectively with spine pain with medication and specific injections.
You can find these docs through referral, or at a local university hospital with a pain clinic.
Thank you for the help trying to understand my MRI. Is it the protruding disc or the degenerative disc disease that would cause inability to bend forward and not be able to straighten back up, along with the hunched-over stiffness I experience after sitting for more than 15 minutes? I have been doing physical therapy for the past 6 months and still have these symptoms.
These kinds of disease cause inflammation that is not usually seen on MRI.
Also, the facet arthropathy (osteo-arthritis) is a painful condition and is probably contributing to your difficulty in flexing and extending the spine.
Again, find a DABPM who can evaluate your facet joint disease and probably treat to reduce pain.
What cause facet afthropathy?
DDD causes facet arthropathy, probably by stretching the joint out of shape, and perhaps because of the same genetic reasons your discs degenerate.
You usually find facet syndrome in moderate - severe cases of DDD, and it causes a great deal of pain discectomy and fusion does not fix.