<s>[INST] hai doctor.i just got my MRI result. Could you please interpret for me? L5-S1: central annulus tears with focal central protrusion of disc. The central herniated disc compressed the Cauda Equina. Bulging disc also causing narrow neural foramina bilaterally resulting L5 existing nerve root impingement. what the different between posterior central protrusion and focal central protrusion disc? [/INST] Hi, There is a soft Kelly like tissue present between two vertebral body which is the disc disc protrusion is a type of disc herniation characterized by protrusion of disc content beyond the normal confines of the intervertebral discuss protrusions are further divided into:broad based : base involves between 90 and 180 degrees of the circumference focal : base involves less than 90 degrees of the disc circumference In case of focal central protrusion, focal and central part of disc is protruded In case of posterior central protrusion, the central part of disc is protruded posteriorly (back that is towards spine)Hope you could understand Chat Doctor.  </s>