The surgery temporarily took the pain away, but it doesn’t sound like anything was addressed with the cause of “blowing your back out”. Sounds like it had something to do with your running technique and your running technique on hills where the treadmill was on an incline.
I would recommend having someone video tape you running so you can see exactly what is going on.
It sounds like you have an active landing from landing on your toes vs landing on the ball of your foot.
When this occurs that calf is always active
Your posture/how you stand may be an impacting factor.
Something occurred for the “recurrent herniation of the same disc”.
Do you sleep on your back?
Adaptation Error: Don’t Sleep on Your Stomach & The Right Bed
Episode 42: Creative Pain, Low Back Decompression, Hammies
Episode 39: Sleep, Pillows, and What Your Low Back Says About Your KB Swing
Jill Miller has a couple great quick fixes to back pain here https://www.yogatuneup.com/online-quickfix-videos
There is a link to a free quick fix here https://www.yogatuneup.com/
It is important to take a systems approach.
Have you addressed your sitting position?
Why Sitting Wrecks Your Mad Hip Action
Episode 351: The One Joint Rule
Episode 276: MobilityWod Google Talk: Desk Bound
Episode 251: High Skilled Sitting/Abdominal Bracing
Episode 187: Death by Chair. How Much Do Actually Sit?
Episode 91: Mobilize In the Position of Death by Chair
Episode 88: Desk Athlete Hip Rescue
Episode 15: You Must Defeat The Evil Chair Part 1
Episode 15: You Must Defeat The Evil Chair Part 2
Pro Episode # 36 – Voodoo Floss Series # 3: The High Hamstring
High Hamstring Gnar, Trigger Points, and Up Stream/Down Stream
Athlete’s ROM: Full Posterior Chain- Are You Dysnormal?
Episode 354: Make Your Own Super Floss/High Hamstring & Hip Gnar Gnar
Episode 272: TJ Murphy Edition and Hamstring Stiffness
Episode 137: Best Hip Extensor (High Hammy) Mob and Better Jerk Shoulders
Episode 104: Hammer Your High Hammy
Episode 82: Protect your scrotch or: Medial hamstring fun
Episode 58: Weird Hamstring Problems and Simple Neurodynmaics
Introducing the Bone Saw: Calf Smash Redux
Episode 303: It’s Not Rocket Science, It is the NASA Calf Game
Episode 237: Heel Cord Love
Episode 194: Why Do You Hate Your Calfs?
Episode 84: Calf Blaster Does Sound Cooler Than Dorsiflexion Blaster