L4 L5 is the Lumbar Vertebra. We have total 33 vertebra.
Cervical: 7 vertebrae (C1–C7)
Thoracic: 12 vertebrae (T1–T12)
Lumbar: 5 vertebrae (L1–L5)
Sacral: 5 (fused) vertebrae (S1–S5)
Coccygeal: 4 (3–5) (fused) vertebrae (Tailbone)
We have 31 left-right pairs of spinal nerves, each roughly corresponding to a segment of the vertebral
8 cervical spinal nerve pairs (C1-C8),
12 thoracic pairs (T1-T12),
5 lumbar pairs (L1-L5),
5 sacral pairs (S1-S5),
1 coccygeal pair.
So these nerves come out through the gap(foramen) in our vertebrae.
Now between two vertebrae there is a barrier(disc made of cartilage
Your report is showing that one of those disc between L4/L5 is bulging and narrowing the space for nerveroot. Still it is in the initial stage and not compressing the nerve significantly.
If left untreated it may progress and compress the nerve which will result severe pain
and function loss.
Thus consult a ORTHOPAEDIC SURGEON
& PHYSIOTHERAPIST as early as possible.
Have a good health.