Can mild thecal sac compression caused by an L4-L5-S1 disc bulge be resolved by time?

The answer to this question depends on a few different factors, so it is difficult to give an exact answer without knowing all of the details. Generally speaking, most forms of mild thecal sac compression caused by an L4-L5-S1 disc bulge can be resolved over time with conservative treatment such as physical therapy and rest.

If the symptoms associated with your disc bulge are mild or moderate in nature and involve localized pain, stiffness or numbness then they will likely improve over time given proper treatment and management. Generally speaking, physical therapy can help reduce pressure in the area by strengthening muscles surrounding the spine and improving flexibility which helps take stress off of nerve roots. During this process you may also benefit from exercises that promote good posture as well as techniques for proper body mechanics when lifting heavy objects. Additionally, it's important to remain active during your recovery period which should include regular walking and swimming when possible. Lastly, it's important to get enough rest each night in order for your body to repair itself effectively from day-to-day activities.

However if after a period of several weeks you do not feel much improvement or if there has been continuous progression of symptoms then additional steps should be taken such as getting a 3D imaging scan (CT/MRI) done of your back or seeking additional medical advice from a specialist like an orthopaedic surgeon who specializes in spinal disorders/injuries.
In conclusion, mild cases of thecal sac compressions due to disc bulging at L4-L5-S1 usually respond well over time with proper management while more severe cases may require further intervention such as advanced imaging scans or specialized surgeries in order for full recovery to occur most efficiently without further complications down the road .