Prolapsed disc L3/4

A problem at this level of the spine is most likely to result in pain and possibly neurological symptoms that are felt in the front of the thigh, and possibly the front of the knee, shin, and foot. These symptoms are different from symptoms caused by pathology at the L4-L5 or L5-S1 levels, as involvement at those lower levels of the spine are more likely to cause pain, tingling, or weakness on the outside or sole of the foot.

See Causes of Leg Pain and Foot Pain

The lower the position of a vertebra in the lumbar spine, the more weight it will hold. The more weight a vertebra supports, the more potential for injury. While the L3-L4 segment is less likely to be damaged than L4-L5 below it, it can still sustain damage easily from either impact injury or natural degeneration.

Pain in the L3-L4 segment can commonly arise from:

The disc can become herniated, resulting in unwanted contact between the disc and the nerve and frequently causing pain.

See Lumbar Herniated Disc: What You Should Know

The facet joints of the segment can become enlarged, narrowing the open spaces of the spine and compressing spinal nerve roots.

See Lumbar Spinal Stenosis: A Definitive Guide

The disc can degenerate naturally over time, which changes the motion of the disc and usually results in stiffness and—much less commonly—tingling in the leg or pain.

You will always have to be careful I'm afraid. It sucks! I used to be able to do kettlebell training, running, plyometrics training you name it but now I can only walk for about 20 mins & struggle walking up the stairs. I'm 29 and feel 79. :-( The human body is a delicate thing but we just aren't educated enough about it in school xx